This study was conducted to determine physicians’ perspectives on factors influencing ABR in Vietnam. (2) Methods: Focus group discussion (FGD) was conducted through in-depth interviews on ABR perspectives with 5–6 physicians from different geographical locations and hospitals in Vietnam between March and June 2020. The research questions were focused on three main themes of (a) knowledge deficiency on ABR and hospital-acquired infection, (b) antibiotic prescribing practice among clinicians in the healthcare setting, and (c) regulations and hospital policies on antibiotic use. The descriptive analysis was performed using QRS NVivo software. (3) Results: A total of six FGDs were conducted among 34 physicians  aged 26–53 years old from six public and six private hospitals in Vietnam. Most of the participants were attending physicians (85.3%) and had 5–10 years of experience in surgical wards (55.9%). For theme (a), a majority of participants agreed that they had adequate information updates on how ABR develops in their clinical setting; and were well aware of hospital-acquired infections. For theme (b), the participants agreed that WHO guidelines and Vietnam national guidelines were two important reference documents in guiding physicians in antibiotic use. For theme (c), the FGD study revealed awareness of ABR, hospital antibiotic policies, and procedures for administrators on antibiotic use that were updated and complied with. (4) Conclusions: While different levels of control measures against ABR are ongoing in Vietnam, several weaknesses in the current antibiotic prescribing strategies in the hospital and clinical setting management policies have been identified in the healthcare system. The research findings will be helpful for policymakers to have better plans of action against ABR in Vietnam. With the emergence of multidrug resistance in bacterial strains, the development of antibiotic resistance (ABR) has become a globally recognized human health threat ,2,3,4. TVietnam, similar to many emerging economies, faces a considerable amount of challenges in attempting to control ABR ,8. A higTo date, the physician’s perspective on the factors influencing ABR in Vietnamese hospitals has not been investigated. The objectives of the study were to determine a physician’s perspective on factors influencing ABR in Vietnam. The findings of this study will help Vietnamese policymakers plan and establish future interventions to improve antibiotic prescriptions in healthcare facilities. Findings will also provide insights to future educational campaigns to improve communication about antibiotic usage between physicians and patients.A qualitative approach using focus group discussion (FGD) was conducted between March and June 2020 in six private and six government hospitals in the northern, central, and southern of Vietnam. Physicians that participated in the FGD were Vietnamese, age between 25 and 60 years old, and who had been working in both private and public hospitals in Vietnam. Basically, the urologists, the pediatricians, the ear-nose-throat (ENT) specialists, as well as general practitioners from both outpatient care and inpatient care were invited to participate in order to enhance the diversity of the participants. The physicians varied by year of experience, geographic region , and position of authority in their hospitals. The purposive sampling was solely used to recruit 5–6 physicians for each group based on the inclusive data, totaling five to six groups. The transcripts of each FGD were translated from Vietnamese into English by native speakers who are experts in pharmacy practice areas, and reviewed simultaneously to evaluate whether the thematic saturation point has been achieved or more interviews are to be scheduled. The saturation point was defined as different themes that were repeated many times in an interview and no other themes emerged at all . After sThe recruitment process was based on the inclusion criteria using snowball sampling, whereby only eligible physicians were invited to join the FGD. The sampling was chosen according to the following criteria: (a) physicians who volunteered to join in the study (volunteers), and (b) physicians of different geographic locations and hospitals (convenience sampling). Participants in each group were healthcare practitioners from both outpatient and inpatient care. Moreover, both male and female physicians and those with low (less than 5 years of experience) or high experience (5–25 years of experience) were invited to participate in each group of the interview to maintain heterogeneity.An interview guide consists of open-ended questions that were used to collect data for this qualitative study. In the semi-structured interviews, the moderators collected answers and ideas from the respondents using the interview guide as a framework. The interview guide was developed based on our preliminary studies and the literature and consisted of three sections, including questions regarding (1) knowledge deficiencies on ABR and hospital-acquired infection, (2) antibiotic prescribing practice among clinicians in the healthcare setting, and (3) regulations and hospital policies on antibiotic use. The interview guide was pilot tested by one of the FGD participants to assess whether it was adequate and relevant for conducting future FGD interviews. Since there were no further revisions or changes needed, the interview guide was used as the final version and for all (six) FGDs for data collection.Data collection was conducted based on the FGD interview guide described earlier. Six FGD interviews were conducted in the Vietnamese language to get a more in-depth picture of the research matter and to validate the results of the questionnaire, and explore participants’ views in more depth. The objective of the study, as stated in an information sheet, was distributed to all participants in each FGD. The participants signed a consent form before participating in an audio-recorded individual interview. Participants were also required to answer questions regarding their sociodemographic information. Interviewees’ privacy and confidentiality were protected by making their comments anonymous. Honorariums were given to the participants for their time accordingly. Additionally, the original recordings were deleted after the transcriptions were completed.FGD interviews were conducted either in an authorized office room at Dong Nai Technology University or in a hospital conference room for the convenience of all participants. Discussions were moderated/carried out for approximately one hour, audiotaped, and transcribed from Vietnamese into English. Notes were also taken by researchers and supplemented with audio records to glean details from the discussion. The identities of all participants were kept anonymous during the FGDs and reporting process.During the discussion, follow-up questions in the interview guide were used by moderators to probe further as well as elucidate/seek clarification from the interviewees. The moderators terminated the discussion when all interviewees agreed that there was no additional information and that the objectives of the interview had been achieved. The saturation point would be reached after six FGD interviews had been completed.Transcripts were translated from Vietnamese into English and were peer-reviewed. The transcripts were put into QRS NVivo qualitative software  to identify key themes and patterns for initial analysis. Themes identified after a coding framework (such as summarizing the dominant themes or presenting similarities and differences in related codes to generate meaning) were developed.n = 18) and 47.1% females (n = 16). Most participants  had been working as physicians in their respective hospitals for 5–10 years. Most of the participants 85.3% (n = 29) were attending physicians, and five were residents, of whom 70.6% (n = 24) were serving in the surgical wards. More than half of the participants  were specialists in their hospitals.A total of six FGDs were conducted with the voluntary participations of 34 physicians from many hospitals. Three major themes were identified from the 06 FGDs, e.g., (i) knowledge of ABR and hospital-acquired infection among the physicians; (ii) antibiotic prescribing practice of clinicians in healthcare settings; and (iii) regulations and policies on antibiotic use in hospitals .The physician’s knowledge of ABR and hospital-acquired infection was investigated. Various reasons for inadequate (lack of awareness) knowledge on ABR and hospital-acquired infection that possibly affect the emergence of ABR among the public were discussed. There were six subthemes on the physicians’ knowledge on antibiotic resistance and hospital-acquired infection, e.g.,(i)information on how antibiotic resistance develops in current clinical settings;(ii)information on how hospital-acquired infection (HAIs) develops in current clinical settings;(iii)common sources of information on antibiotic use in hospitals;(iv)causes of knowledge deficiency among physicians that can contribute to antibiotic resistance;(v)impacts of antibiotic resistance in current clinical settings and how to keep up to date with new developments in clinical field.Most of the participants (88%) agreed that they and their colleagues had sufficient information on how ABR develops in their hospitals.The attending physicians in our hospital have sufficient information on how antibiotic resistance develops in the current clinical setting, as evidenced by the fact that in the course of their works, under the management and supervision of the hospital’s board of directors, they provide proper prescription.”“FGD 1, participant 4For the prescribing and dispensing of drugs, especially antibiotics, during prevention and treatment purposes, our medical team has proper prescription recorded, one of them has involved in teaching at some medical universities in and outside the region, and has the opportunity to participate in medical research projects/activities.”“FGD 5, participant 1Apart from diagnosis and treatment, physicians and medical staffs, in general, also participate in research projects and publish articles in scientific journals on medical specialties annually.”“FGD 2, participant 3“This is controversial antibiotic resistance is constantly changing, depending on the hospital and each locality. Up to this point, we have not had any hospital focusing on research on this issue, and only used general materials in the world and in Vietnam at central hospitals, but the problem lies in the fact that, not all documents are suitable for each locality.” FGD 6, participant 1. This suggests that each local hospital should develop its own guidelines for promoting appropriate antibiotic use. To accomplish this goal, it is also necessary to have the support of national and local health authorities, as well as coordination and cooperation between hospitals. Throughout the FGDs, there were no discussions about whether the specialists had provided the wrong antibiotic prescription or given the wrong consultation to patients. There was no statement mentioned that the participants had insufficient information on how ABR develops, except for one comment, as All FGDs discussed how hospital-acquired infections (HAIs) develop in their workplace. The participants stated that most of the hospital’s physicians were well aware of this issue. They had proper prevention for themselves and their patients; accurate diagnosis with the symptoms of HAIs, and a proper antibiotic prescription. The design and arrangement of hospital supplies were well managed by hospitals to avoid the growth and spread of bacteria. Airflow in the operating room was regulated using two-way circulations (in and out) for separate areas: one for operating room staff to change clothes before entering the operating room area, and the operating room area itself. Programs for monitoring hospital infections were seriously implemented. Disinfection and sterilization of the hospital were carried out very strictly. In addition, basic hygiene for medical staff is also strictly enforced.There were physician’s awareness of nosocomial infections and compliance, e.g., regular hand hygiene, neat clothing and hair during work and before entering operating room. The design of operating rooms, airflow in and out, and cleaning of hospital utensils were also well done.”“FGD 1, participant 3Currently, our hospital has an infection control department with the role of monitoring and disseminating information periodically through weekly and monthly briefings for all hospital staff. When there is an infection in any department, they will notify other departments.”“FGD 4, participant 2There was no statement that the physician in their clinical setting had insufficient information on how HAIs develop.Most of the FGD participants mentioned that the practice guidelines issued by the Vietnam Ministry of Health (MOH), in 2015 are a common source of information on antibiotic use in their hospitals. Some of them mentioned that they could also acquire relevant information from various internet sources, and by attending conferences, workshops, seminars, and pharmaceutical advertisements , for continuing medical education. A few of the participants mentioned that they could find updates in special journals.Our hospital refers to the “Instructions on Antibiotic Use” published by the Ministry of Health (issued with Decision no. 708/QD-BYT dated 2 March 2015) for antibiotic use. The process of prescribing antibiotics is mainly based on this guideline, however in some special cases, we refer to other documents including guidelines from foreign medical companies such as Stanford, Medscape, combined with documents of Central hospitals and after consultation among different specialists.”“FGD 4, participant 1Depending on each case, before prescribing antibiotics to patients, I follow the guidelines of the Ministry of Health and the guidelines of the central hospital. In addition, for some special cases, there must be consultation with the professional directorate, pharmacy department, internal medicine department, and emergency department.”“FGD 4, participant 2The source of information about new antibiotics is updated based on the recommendations of pharmaceutical companies, but it is also somewhat limited. For myself, as well as my colleagues in the faculty, the source of information is obtained by attending seminars. In addition, the pharmacy department of our hospital is the unit to access and disseminate updated information on antibiotics to other departments.”“FGD 6, participant 5When asked to suggest solutions to help specialists and clinical staff acquire up-to-date information on antibiotic usage and resistance, several ideas were raised and discussed. They expressed their desire to establish research groups on the state of antibiotic use in inpatient and outpatient treatment at the national level. They are aware that the problem of ABR is very complicated, as Antibiotic resistance is complex and continuous; we need to have research on each location and detailed statistics. The establishment of national-level in-depth research groups on the topic of antibiotic resistance is necessary. Because when participating in such research, we will have the opportunity to learn and exchange information with each other, thereby serving the diagnosis and treatment of diseases as well as having effective antibiotic prescription. Besides prescribing based on antibiogram results, empiric antibiotic prescribing is also effective in treatment when the physician has good experience.” FGD 4, participant 6; and “I propose the establishment of national-level research projects on antibiotic use and antibiotic resistance. If we can implement such topics, our hospital’s medical team will have the opportunity to learn and update information in a timelier manner.”“FGD 5, participant 2The FGD participants expressed their opinions on the causes of how limited knowledge might hamper the prevention of antibiotic resistance. The common causes include a lack of self-updates, and a lack of regular and advanced training from hospitals. There were no comments from the physicians on the comprehensive infection control programs available, and/or antibiotic stewardship strategies available. Only a few of the medical staff complained about the lack of opportunities to attend conferences and continued their education until they graduated as medical doctors. In addition, some also expressed their desire to receive online teaching activities and provision of written national guidelines. The lack of knowledge among medical professionals in the use of antibiotics causes antibiotic resistance in the community. The first reason is that they do not update information themselves, and the second one is that the use of antibiotics in treatment is not completely according to patient’s condition but according to other benefits . Usually, a majority of doctors work under the direction of the hospital management board, following the rules and regulations.”“FGD 1, participant 1At our hospital, the connection and transfer of experience between generations of doctors is very good, they share experiences for the younger generation, and learn from each other. Therefore, this should not be the cause of the lack of knowledge about antibiotic use among physicians. I think the main reason is the lack of regular training, advanced training, and more importantly, the sense of self-updating of each doctor so that they don’t become obsolete.”“FGD 4, participant 6In order to prescribe antibiotics to patients according to the results of microbiological tests or antibiograms, we need a certain time of 5–7 days, thus, the answer of whether or not doctors who prescribed antibiotics according to experience is “yes”, in fact.”“FGD2, participant 2Not being able to participate in lectures, and research projects is not the cause of the lack of knowledge about antibiotics and antibiotic resistance.”“FGD 6, participant 1There were suggestions to make physicians more updated and knowledgeable to antibiotic use and resistance to prevent ABR, For instance, by joining a national project on antibiotic use and antibiotic resistance, writing and publishing journals, and/or presenting their research findings in seminars or conferences.Some physicians excessively care about their family’s finances. In Vietnam, the financial resources for doctors are quite limited, so they look for a high-paying job, and of course high salary is equivalent to a lot of work, thus, they do not have adequate time to update their knowledge. Additionally, if a physician work at a low-wage state hospital, he/she will find a part-time job, so he/she does not have time to update their knowledge, hence, in order for them to have enough time to update their knowledge, salary policy should be changed by government.”“FGD 3, participant 3I think in order for the medical team to have up-to-date knowledge on antibiotic use, the hospital’s director board should create more opportunities for them to participate in specialized seminars and conferences as experts or speakers. At the same time, every year the hospital should encourage them to participate in research and publish articles in scientific journals.”“FGD 6, participant 2Most of the FGD participants did not discuss much about the impact of ABR in their current clinical settings. In some FGDs, the participants expressed their concerns about the impacts, including the increase in morbidity and mortality, more difficulty in treating the basic infectious condition, the high cost of treatment, and the need for patients to spend more time in the hospital to cure the disease. For patients whose infections are resistant to antibiotics, it becomes more difficult to use antibiotics to treat the infections. In such situation, we have to be careful in performing microbiological and antibiotic susceptibility tests, in order to choose the most optimal treatment regimen for the patient. It usually takes longer time to treat these resistant infections. The cost of their treatment is also higher than usual compared to other patients who respond well to the initial course of antibiotics.”“FGD 1, participant 2This puts a heavy burden on both the patient and hospital, when the length of treatment is prolonged. For patients infected with multi-drug resistant bacteria, our hospital’s doctors will put them in an isolation room to limit cross-infection with other patients with weak resistance.”“FGD 2, participant 1In Vietnam, each clinical setting has identified several approaches to help physicians and medical staff keep abreast with new developments in the clinical field. It is revealed that some hospitals encourage their staff to attend internal and external conferences, seminars, and workshops, while some others provide resources and reading materials, such as specialized documents, books, and journals.In order for medical staff to stay up-to-date with new developments in their field, I think they should be given more opportunities to participate in conferences and seminars within and outside the region, but in reality, in my hospital such opportunity is rare.”“FGD 5, participant 1Currently, specialized documents are updated but not regularly. I think, update frequency should be weekly or monthly. However, it is difficult to implement in the current context of both the provincial and central hospitals, the currently every year update is good enough.”“FGD 6, participant 3Realizing the importance of medicine prescribing, especially antibiotic prescribing practice among clinicians in a healthcare setting, national guidelines are made available to Vietnamese hospitals to prevent/reduce indiscriminate prescriptions in order to develop outpatient treatment protocols, manage inpatient treatment regimens, and limit drug abuse. Factors influencing antibiotic prescribing practices in outpatient and inpatient care were investigated in this study.Antibiotic prescribing practices in outpatient care can lead to antibiotic resistance in clinical settings. This is one of the most discussed parts of all FGDs. The participants expressed their thoughts about various factors that would influence antibiotic prescribing practices in outpatient care. According to the participants, the process of making decisions on antibiotic prescribing should adhere strictly to hospital guidelines, rules, and regulations. In some cases, empirical treatment was given to patients before the results of antibiotic susceptibility tests were received. Physicians’ experience, patients’ health history, financial status, and patients’ expectations are other factors affecting the prescription of antibiotics in outpatient care. Patient compliance was also one factor that influenced their antibiotic prescribing practice for outpatients. Among the factors that have been identified, physicians’ experiences were identified by almost half of the physicians as the most relevant.Discussing the factors that affect antibiotic prescribing in outpatient care, the first thing I want to say is that based on experience in prescribing antibiotics, a doctor can recognize whether an antibiotic is consistent with the causative agent in the patient or not. Next is the patient’s financial ability, in fact, each antibiotic has a different price, so depending on the patient’s economic condition, the doctor will have a suitable choice.”“FGD 1, participant 3Depending on the patient, if they don’t have money, our doctors will advise and prescribe low-cost antibiotics. That is, when advising on antibiotics, we advise on the effects of the drugs along with their prices, so if the patient is not economically eligible, the doctor will prescribe a cheaper antibiotic.”“FGD 2, participant 4In determining the treatment regimen, for example, when a patient with pneumonia was admitted to the hospital, the doctor will initially prescribe a beta-lactam antibiotic, or a second or third-generation of cephalosporin , plus a common macrolide or an antibiotic used to treat atypical bacteria, and gram-positive bacteria. Currently, as bacteria are completely resistant to the macrolide group of antibiotics, the doctor will not prescribe such regimen anymore, instead; they will prescribe a third-generation cephalosporin in combination with another antibiotic to improve treatment outcome because the rate of bacterial resistance has already become too high.”“FGD 3, participant 5Following the words of a colleague, I also want to share another influencing factor, related to the drug stock. When the hospital’s available drug stock does not meet the requirements, it is difficult to choose the desired antibiotic for patients. Honestly, when a certain pharmaceutical brand enters the hospital to present the drug and introduce it, they need to go through many “backdoors”. The quality of drugs between brands is of course not the same. In terms of pharmacology, we do not discuss, the dosage levels are similar. However, the time of release and the amount entering the blood of patients when using such drugs are different, effectiveness in treatment hence also different. We ourselves, when prescribing antibiotics, might be governed by the drug list available in the pharmacy store of the hospital.”“FGD 6, participant 3The factors listed below are all factors that influence antibiotic prescribing practice: patients’ health history, current clinical conditions, patient demand for antibiotics, physicians’ experience on antibiotic prescribing, cost of treatment, patients’ compliance, physicians’ experience in treating the infectious diseases, antibiogram availability for the physicians to assess antibiotic susceptibility and select empirical antibiotic treatment.”“FGD 2, participant 1Similar to outpatient antibiotic prescribing routine, antibiotic prescriptions for in-hospital patients were also influenced by factors, such as antibiogram availability, experience of physicians with infectious diseases, patients’ health history, and current clinical conditions. Physicians agreed on how antibiotic prescribing practices for inpatient care might lead to the emergence of ABR in their current clinical settings. Hence, some physicians expressed their foreseen weaknesses or limitations in their current antibiotic prescribing strategies in their hospitals and gave suggestions for further improvement. When prescribing antibiotics to outpatients, I have to consider a lot about the patient’s history, their current medical condition, whether the antibiotic is appropriate or not. For example, if the patient’s liver and kidneys have problems, it is not suitable to use that antibiotic, I have to change to another suitable one.”“FGD 1, participant 1The economic status of the patients was one of the factors influencing my choice of antibiotics for their treatment.”“FGD 1, participant 5When I want to prescribe certain antibiotic to a, but the hospital pharmacy department doesn’t have that antibiotic, I have to change it to another one. Therefore, the list of antibiotics available in the hospital pharmacy is also one of the influencing factors.”“FGD 4, participant 3The physician’s prescription has impacts on the antibiotic resistance among people in the community, because like outside the community, there is also abuse (indiscriminate use) of antibiotics inside the hospital. For example, even if the status of the patient is not up to the point of needing antibiotics, he/she is still taking antibiotics because of some influencing factors. That is real and happening in my workplace. In addition, in some cases patients with recurrent infections, the physicians have to use many different antibiotics due to changing treatment regimens. This gives rise to multi-antibiotic resistance.”“FGD 5, participant 1Doctors prescribe antibiotics by experience, of course, for inpatients, we all do a test (sputum culture) before prescribing antibiotics, especially injectable antibiotics. As for oral antibiotics, it is not necessary to culture sputum to make an antibiogram.”“FGD 3, participant 1The use of antibiotics in the community is very indiscriminate, an ordinary citizen can go to any pharmacy to buy antibiotics at any time. When they use antibiotics ineffectively, they will go to the hospital, the application of escalation/de-escalation of antibiotic will no longer be appropriate because it takes time, and the bacteria might have become resistant. In private hospitals, doctors use moderate or high levels of antibiotics, e.g., strong antibiotics, higher than what the patient used before admission, of course but not as high as in the big central hospitals.” “FGD 3, participant 4One of the causes leading to ABR was the widespread, inappropriate use of antibiotics without a medical prescription, making them less effective or ineffective. According to the survey results on the sale of antibiotics at drug retailers in rural and urban areas in the northern provinces, the awareness of antibiotics and ABR among drug sellers and people is particularly low, especially in rural areas. Most antibiotics are sold without a prescription, 88% in urban areas and 91% in rural ones . Two subStrengthening the control of antibiotic prescription and selling prescribed antibiotics are two strategies recommended by the WHO and Vietnam MOH for reducing ABR. Decision 4041/QD-BYT of the MOH on “Approval of the project to strengthen the control of antibiotic prescription and the sale of prescribed antibiotics for the period 2017–2020”, in order to raise public awareness about the proper use of antibiotics, and enhance the responsibility of professional clinicians, especially prescribers and retailers, in implementing the law, thereby contributing to reducing ABR, drug abuse, and inappropriate drug use. Most of the participants thought that the regulations were strict enough for physicians to comply with in order to control ABR. Some expressed their opinions that the surveillance program, the transparency and the feedback on antibiotic consumption, costs, and trends in the hospital setting were essential in preventing ABR. The physicians agreed that regulations of the use of antibiotics contribute to ABR control in their clinical settings. In addition, based on their own prescribing experiences, they foresee gaps and weaknesses that need to be improved in the current regulations regarding the use of antibiotics.Our hospital always adheres to the regulations on the use of antibiotics. This is done strictly. In the case that physicians use antibiotics for prevention and treatment purposes for patients improperly, the incident will be recorded by the management boards and put in the monthly performance evaluation, not just a mere reminder.”“FGD 1, participant 3In this regard, I certify that our hospital is complying with the regulations of the Ministry of Health. I also comply well. However, not all physicians or medical staffs performed well, for many different reasons, maybe due to their knowledge, or personal benefits.”“FGD 4, participant 2In general, our hospital is well managed, the medical staff always strictly follow the regulations of the MOH. However, there are also flaws and inadequacies. Firstly, on the pharmacy side, they mostly know about pharmacology, while we work on the clinical side and when we do something wrong, they don’t even know. The pharmacy department themselves are not correct in some cases of dispensing drugs to patients due to the limitation of the drug store they manage.”“FGD 5, participant 5All the participants in the FGDs mentioned that there were policies and procedures for administrators on the use of antibiotics that their hospital was following. Information management policies on the use of antibiotics were strictly implemented and controlled. Most of the participants were aware of how the policies on the use of antibiotics can help in reducing ABR in their clinical setting, under the effective-controlled antibiotic stewardship programs. Nevertheless, participants from the suburban area expressed their opinion on the fact that physicians in their current clinical setting did not comply with existing policies, some said that the management policies were poor in their hospital. From that, there were suggestions from the physicians for the policymakers or governing bodies regarding the use of antibiotics to prevent ABR. About the policy of using antibiotics, my hospital is very clear. If the doctor does not follow those policies, firstly they will be reminded, then if they still repeat the mistakes, their names will be included in the monthly emulation assessment, or they need to meet the management board directly to resolve the circumstances depending on the level of illegal actions repeatedly.”“FGD 1, participant 2In addition, our hospitals also have software support to report illegal actions and statistics of the use of antibiotics”“FGD 1, participant 3The suggestion from participants in FGDs were recorded as follow: Regarding the penalty in the indiscriminate use of antibiotics, it would be great if the government had stricter control policies, especially in rural areas. Because most pharmacies in urban areas sell prescription drugs, not indiscriminately. However, in rural areas, this is not always strictly followed. If we want to apply penalty or sanctions, we implement in the urban area first, then in the suburbs and rural areas. It is necessary to strictly prohibit private clinics and pharmacies to sell antibiotics without a medical prescription, they will be fined, banned from doing business, depending on the government.”“FGD 3, participant 4The most practicality to improve antibiotic prescription and indiscriminate use of antibiotics, in my opinion is that we have to manage the supply sources of the antibiotics, because it is very complicated and rampant currently. Besides, the cost of antibiotics is also a problem worthy of interest, and need more analysis. We look forward to hospitals to ensure that antibiotics with reasonable prices can reach patients as compared to the original one.”“FGD 4, participant 4The procedure of doctors and staff in the policy of using antibiotics in the hospital is not quite reasonable, but more importantly we should do it to train them, helping them update information. Because we have to recognize that, most doctors have strong personality, sanctions for them as an extra catalyst for non-regulated antibiotics during prescriptions.”“FGD 6, participant 2I think hospital side should have updated new documents to provide the medical team timely updates. Especially, for the case of patients with severe infections, we need consultation and optimal treatment protocols best updates from the central or international hospitals.”“FGD 5, participant 1A qualitative study using the FGD approach has been conducted to assess physicians’ perspectives on factors influencing their antibiotic prescribing practice as well as ABR in both outpatient and inpatient healthcare settings in Berlin, Germany . The resMost of the participants in all FGDs agreed that they and their colleagues had sufficient information on how ABR developed in their hospitals. Some evidence supports their answers, including correct antibiotic prescription to patients and patients’ education, attending teaching sections and medical conferences as an attendee and speaker, participating in medical research projects and works, and publishing articles in scientific journals on medical specialties. In other words, there was no mention that the participants had insufficient information on how ABR develops. Only one comment from FGD 6, participant 1 that the physicians in sub-urban and rural areas might had insufficient knowledge on ABR. In fact, limited knowledge about the use of antibiotics and updates on antibiotic guidelines have been reported to hamper prevention and control of ABR in the community ,11,13. TAccording to the opinions of the FGD participants, the impact of ABR to the current clinical settings is long term and un-surmounted, as it causes an increase in morbidity and mortality, more difficulty in treatment, increased cost and duration of hospital stays. Microbiological investigation and antibiotic susceptibility tests are important to determine the most optimal regimen for the patients, which indirectly minimizing the impact of ABR. In addition, following the antibiotic guidelines and policy, patients infected with multidrug resistant organisms should be placed in an isolation room to limit cross-infection with other patients. The findings obtained in this study suggests high awareness of the physicians on the impact of ABR, which has also been recognized as a public health burden worldwide. The participants in this study were also well aware of hospital-acquired infection and its consequences. This is consistent with the results from the study of . They weThe participants have also identified several common sources of information about the use of antibiotics use in the hospital, which include practice guidelines issued by Vietnam Ministry of Health (MOH), 2015; internet source, medical education, conferences, workshops, seminars, and pharmaceutical advertisements . A few participants mentioned that they could obtain updates on antibiotic use and ABR by referring to certain medical journals. However, in general, they felt that the above sources of information did not meet the need for regular updates on the use of antibiotics and ongoing ABR in Vietnam. There were suggestions made during the discussions to diversify information updates. The participants wish to establish national-level research projects on the use of antibiotics and ABR, so that they would have more chances to learn and exchange information with each other in the diagnosis and treatment of diseases. Lack of knowledge and inappropriate extrapolation of knowledge about medicines were common causes of prescribing error. It is therefore important that prescribers have immediate access to quality up-to-date drug information to ensure safe and effective prescribing. The FGD also discussed methods of keeping physicians up-to-date in medical field. Some approaches mentioned including encouraging staffs to attend internal and external conferences, seminar and workshop; and providing resources such as documents, books, and medical journals. Weekly/monthly updates on the use of antibiotics and ABR are essential. These resources are also reported to be important and are used by doctors for prescribing in Ireland . The FGD participants revealed the implementation of proper antibiotic use based on guidelines from WHO and Vietnam’s national MOH for development of outpatient treatment protocols, inpatient treatment, and limit drug abuse. In fact, all participants agreed/realized that good antibiotics prescribing practice is an important factor for prevention and control of ABR. In different countries, people hold different ideas about health, causes of diseases, coping strategies, and treatment modalities . These iAnother aspect, antibiotic prescribing practice for inpatient, was also deeply discussed in most FGDs. As compared to outpatient care, prescribing processes for inpatient ones have been more strictly controlled by hospital boards. Factors such as antibiogram availability, experience of the physicians with infectious diseases, patient health history and their current status are mentioned in the participant’s discussion. The physicians also expressed weakness or limitation of their current antibiotic prescribing strategies in the hospital and suggested for further improvement. Although the application of escalation/de-escalation of antibiotics were implemented by the physicians for in patients, however, it may not timely for infections due to multidrug-resistant bacteria. Although, de-escalation strategy is recommended to prevent the emergence of resistant bacteria ,27 therePrevious studies have shown that some of the leading causes of ABR include the lack of official government policy on the rational use of antibiotics in both public and private hospitals ,29,30,31Physician prescribing behavior is associated with antibiotic misuse. Therefore, antibiotic prescribing behavior should be changed and updated according to the latest guidelines to reduce ABR, which is an issue of particular concern in many countries around the world ,32. RegaMost of the participants thought that the regulations were strict enough for physicians to be compliant in order to control ABR. These findings are consistent with the study of . Some exIt is necessary to strictly manage the supply sources of the antibiotics, because it is very complicated and rampant currently. The cost of antibiotics is also a problem worthy of interest and needs more analysis by legislators or policymakers. Hospitals should ensure antibiotics with reasonable prices can reach patients. More importantly, the management boards should train physicians and medical staffs to update information in the clinical settings as reported in this and previous studies ,13,24,33There are some limitations to this study. The convenience sampling may be biased towards including groups of young physicians who were selected for FGDs. In the interpretation of the results, it needs to be carefully considered before drawing conclusions from the sample selected in the qualitative research phase, given the qualitative nature of this study. Participants were based on southern areas of Vietnam, which means that physicians and medical staff from other geographical locations (such as middle of Vietnam and northern area) might be under-presented. The low presentation of high-experience physicians must be considered. Socially desirable responses of the participants obtained may also be exist due to self-report-answer in the FGDs. Although measures were taken (random coding by peer) to reduce bias, the transcript-coding step may also be another limitation of study. The subjective analysis in the process of interpreting the collected data can be one of the limitations, although neutrality was attempted. Insights from this study can be used as a basic pattern for FGD research design to access the physician’s perspective on the use of antibiotics and resistance among the public. It is highly recommended that future studies should target more on physician’s recommendations and suggestions on the government’s regulations and policies to improve the ABR situation among the public in Vietnam.This study highlights a physician’s perspective on antibiotic usage and the emergence of antibiotic resistance in Vietnam using the FGD approach. While different levels of control measures against ABR are ongoing in Vietnam, several weaknesses in the current antibiotic prescribing strategies in their hospital and clinical setting management policies were identified in the healthcare system. Based on the research outcomes, practitioners, policymakers, and the community should work together to find effective solutions and measures to abrogate ABR for a better healthcare system and environment. In addition, the findings should also provide insights into future education-based interventions to improve rational prescribing and use of antibiotics.


Aiming to provide a solution for natural resource consumption and agricultural waste pollution, jujube nucleus is utilized as a substitute for coarse aggregate in the preparation of lightweight aggregate concrete. The effect of the jujube nucleus (JN) replacement ratio and the elevated temperature on the uniaxial compressive stress–strain curves of jujube nucleus concrete (JNC) are experimentally studied. The results show that the failure of the JNC prisms became more serious with the increase in the JN replacement ratio. The linear proportion in ascending branch and the descending slope of the stress–strain curves for JNC increased gradually with the increase in the JN replacement ratio and elevated temperature, which is probably owing to the higher porosity and lower stiffness of the jujube nucleus, compared to natural aggregate. Moreover, as the JN replacement ratio and the elevated temperature increase, the peak stress and elastic modulus in the stress–strain curves of JNC decrease gradually, whilst an increase in the peak strain shows up, which is possibly due to the growth of hydrate calcium silicate and calcium hydroxide hampered by sucrose molecules. Based on the test results, a series of theoretical formulas are proposed to predict the compressive performance of JNC. A material constitutive model is developed for describing the stress–strain relationship of JNC by considering the JN replacement ratio and elevated temperature. In addiach year . As a reach year .In China, jujube nucleus, considered as one of the major agricultural by-products, would be discharged by more than 3 billion tons every year . How to The mechanical properties of agricultural waste concrete have been investigated for decades. However, study on the stress–strain relationship of agricultural waste concrete under uniaxial compressive loading is rarely involved. The effect of coconut shell (CS) as an alternative coarse aggregate for concrete materials was studied by Tomas and Ganiron . The resThe fire resistance of concrete materials is one of the indices to evaluate the durability of concrete in engineering structures , which fBased on the above-mentioned review, a lack of data on the stress–strain relationship of agricultural waste concrete under uniaxial compressive behavior is indicated. Therefore, the jujube nucleus is utilized herein as a coarse aggregate in the preparation of agricultural waste concrete, as shown in The concrete mixture was prepared by using natural silica sand and natural limestone gravel sourced from local suppliers, Xi’an, China. Following China’s standard JGJ 52-2006 , the phyThe jujube nucleus used herein as a substitute for natural coarse aggregate was collected from a fruit processing facility located in Shaanxi province, China. The surface of the jujube nucleus was generally enveloped by large amounts of unripped flesh that was abundant in saccharides such as glucose, fructose, sucrose, oligosaccharide, arabinose, and galactose . SaccharFollowing the Chinese standard GB/T 17431.2-2010 , these jThe physical properties of the jujube nucleus were tested, as shown in For the ordinary concrete without jujube nucleus, the mixture proportion was designed according to China’s JGJ55-2011 standard . Under tPrisms of 150 mm × 150 mm × 300 mm were prepared for testing the uniaxial compressive strength, elastic modulus, peak strain, and the whole stress–strain curves of JNC . Specimen identification, as listed in The uniaxial compression test of JNC was performed by a hydraulic compression machine with a maximum test load of 2000 kN. Specifically, a force control method was used to impose compression on the sample at a speed of 1 kN/s. Once the load reached 15 kN, the force-controlled method was used via the displacement-controlled method at a rate of 0.025 mm/s until the specimens failed. Two strain gauges were arranged on each side of the specimen to monitor the longitudinal strain, as shown in The high temperature furnace in which the concrete specimens were preheated is illustrated in Prior to the uniaxial compressive test, the concrete specimens were heated from room temperature to a specific target temperature  at a rate of 10 °C/min. Mohamedhai et al.  pointed The failure phenomena of all the specimens tested under the uniaxial compressive loading for JNC are shown in For ordinary concrete, namely without jujube nucleus, shear failure was observed in all the specimens, and a main diagonal crack occurred as a result of uniaxial compression. As the elevated temperature increased, more vertical cracks appeared in all the specimens besides the diagonal crack. Under heating, the evaporation of free water and the decomposition of hydrate calcium silicate (C-S-H) and calcium hydroxide resulted in the growing number of pores in the concrete. Thus, the crack propagation of the concrete after elevated temperature under the uniaxial compressive loading only needed to dissipate a little energy, compared to that of ordinary concrete without heating . For jujube nucleus concrete (JNC), the number and width of diagonal and vertical cracks increase with the increase in the jujube nucleus replacement ratio and elevated temperature, which is mainly due to the low stiffness and high porosity of jujube nucleus, which may result in the crack propagation pattern being transferred from the damaged interfacial transition zone to aggregate penetrated under the uniaxial compressive loading, reflecting the weaker energy dissipation capacity of JNC . HoweverThe whole stress–strain curves of JNC under the same JN replacement ratio after experiencing various elevated temperatures is presented in 2 crystal, having a larger volume in the concrete, begins dissociation, which causes cement paste dehydration [It can be seen that as the elevated temperature increases, the peak stress and peak strain of JNC decrease gradually. Additionally, the slope of the stress–strain curves, for both the ascending and descending branches, decreases with the rise in the elevated temperature. It is noted that when the elevated temperature exceeds 400 °C, the peak stress and peak strain of ordinary concrete show a larger reduction than those of JNC. This may be because when the elevated temperature exceeds 400 °C, the Ca (OH)ydration , as showThe whole stress–strain curves of JNC under the same elevated temperature with the various JN replacement ratio are presented in It can be seen from After a 28-day curing process, the stress–strain characteristics with various jujube nucleus (JN) replacement ratios after experiencing various elevated temperatures were derived from the stress–strain curves of JNC, including the peak stress, peak strain, and elastic modulus, as tabulated in As shown in It can be seen from ηc is the reduction factor of the relative value –(3). The elastic modulus of JNC is taken as the secant modulus from the origin to 40% of the peak stress. Analogous to the peak stress of JNC, the elastic modulus of JNC decrease gradually with the rise in the JN replacement ratio and the elevated temperature, as shown in ρ is the density of the jujube nucleus.To predict the elastic modulus of concrete materials, Equations (4) and (5) are recommended by GB/T 50010-2010  and Yu   is recommended by Yu   is changed by the addition of jujube nucleus (JN). To tackle the phenomenon, a constitutive model of JNC corresponding to the requirement of structure design is needed, which is important for both practical engineering design and numerical calculations. A, B, and the parameter of descending branch, αc. The peak stress of concrete, A and B, descending branch parameter, α) need modification by considering the effect of replacement ratio and elevated temperature.As shown in A, B, and αc can be determined through a nonlinear curve fitting for the stress–strain curves of jujube nucleus concrete (JNC) under the effect of the jujube nucleus (JN) replacement ratio and elevated temperature. Specific data are tabulated in The values of parameters A is the ratio of elastic modulus to peak secant modulus for concrete. Ding et al. [A is, the longer the linear stage in the ascending branch of stress–strain curve is, and the more the accumulated elastic strain energy of the lightweight aggregate is. A under the effect of the JN replacement ratio and the elevated temperature. It can be seen from A climb to peak when the JN replacement ratio is no more than 25%. It can be concluded that the jujube nucleus has more elastic strain energy under the uniaxial compressive loading than natural aggregate. However, the further rise in the JN replacement ratio and the elevated temperature increases the sucrose molecule content in the JNC, and the values of the parameter A decrease rapidly.The definition of parameter g et al.  shows thA can be expressed by the peak stress. However, the predicted values of parameter A are discrete when using Equation (12), as shown in A. ρ stands for the density of the jujube nucleus.Ding et al.  shows thB reflects the degradation degree of the elastic modulus for concrete [B under the effect of JN replacement and elevated temperature. It can be seen that the values of parameter B slip down gradually to the bottom with the rise in the JN replacement ratio and the elevated temperature. The difference is that the values of parameter B decrease rapidly when the JN replacement ratio exceeds 25%, for the same reason for the decline of the values of parameter A.Parameter concrete . Figure B can be expressed by parameter A. However, the predicted values of parameter B are overestimated by using Equation (13), as shown in B. A is obtained from Equation (15).Ding et al.  shows thαc reflects the slope of descending branch curve for concrete [αc is, the more obvious the brittle characteristic is. αc under the effect of JN replacement ratio and elevated temperature. It can be seen that analogous to parameter A, the rise in the JN replacement ratio and elevated temperature would make the values of parameter αc climb to the peak when the JN replacement ratio is no more than 25%, which may be because the jujube nucleus has lower stiffness than natural aggregate [αc slips down to the bottom rapidly, which is attributed to the same reason for the parameter A deterioration.Parameter concrete . This meggregate . When thA, descending branch parameter αc can also be expressed by the cubic compressive strength [αc are overestimated by using Equation (14), as shown in B. Similar to parameter strength . HoweverAs shown in This paper investigates the feasibility of using jujube nucleus as a substitute for coarse aggregate in green lightweight aggregate concrete, aiming to provide a solution for natural resources consumption and agricultural waste pollution. The uniaxial compressive behavior of jujube nucleus concrete (JNC) was tested and discussed in detail by considering the effect of the jujube nucleus (JN) replacement ratio and the elevated temperature. (1)Different from ordinary concrete, the increase in the JN replacement ratio and the elevated temperature would result in the growing number and width of the vertical and diagonal cracks for JNC whilst the linear proportion in the ascending branch and the descending slope increased gradually for the stress–strain curves of JNC, probably due to the low stiffness and high porosity of the jujube nucleus.(2)The rise in the JN replacement ratio and elevated temperature would decrease the peak stress and elastic modulus but would cause a rapid increase in the peak strain in the stress–strain curves of JNC, which is ascribed possibly to the fact that sucrose molecules can hinder the growth of calcium silicate hydrate and calcium hydroxide to a larger content.(3)When the JN replacement ratio reaches 25%, the reduction in the peak stress and elastic modulus is 26.36% and 11.27%, respectively, whilst the reduction in the peak stress and elastic modulus of JNC under 100% replacement ratio is 96.60% and 59.48%, respectively. The peak strain of JNC under 25% and 100% replacement ratio increases by 15.93% and 67.24%, respectively.(4)When the elevated temperature is up to 100 °C, the peak stress and elastic modulus for JNC under 25% replacement ratio decrease by approximately 8.00% and 4.16%, respectively, whilst the reduction increases to 33.00% and 20.52%, respectively, under 400 °C heating. The peak strain of JNC with 25% replacement ratio increases from 2.53% under 100 °C to 19.70% under 400 °C.(5)A material constitutive model is developed based on the test results for describing the stress–strain relationship of JNC under the effect of the JN replacement ratio and the elevated temperature. The predicted stress–strain curves using the model can match well with the tested stress–strain curves under the different JN replacement ratios and elevated temperatures.It must be mentioned that the mechanical properties of JNC are acceptable with a 25% substitution ratio, indicating the potential utilization of JNC in pervious, sound-proof, and insolation members towards eco-friendly design. However, the mechanical properties of JNC decrease rather too significantly under a substitution ratio larger than 50% to be of practical interest. Thus, it is necessary to continue the experimental research to refine the formulas for the compressive performance and the stress–strain model of JNC, under substitution ratios between 0% and 35% at small intervals to have more data in this range of ratios. Because normally the durability of lightweight aggregate concrete is not as good as ordinary concrete , more st


The main goal and novelty of this study is to show the transferability of practices and experiences with the use of reclaimed sand worldwide in the case in two different regions, the Czech Republic and India, which is necessary for both regions due to the sand availability (Czech Republic) and illegal sand mining including criminal offences (India). Due to the deteriorating environmental impacts associated with sand mining, finding substitution possibilities for natural sand is becoming more important worldwide. It is realized that the reuse of construction demolition waste concrete is inevitable in the pursuit of circular concrete and cleaner production, envisioned by the United Nations (UN) as the attainment of ensuring sustainable consumption and production patterns  with an inclusive approach of partnerships to achieve the goal  for the validation of results. The basic material properties of reclaimed sand were examined, and its impact on the physical, mechanical, and durability properties of concrete with complete replacement of sand was evaluated. Generally, a slight decline in properties of concrete with fine recycled aggregate was found. No significant decrease was found from usage possibility in the point of view of its utilization in specific structures and conditions. The research shows the slight differences of results between the Czech and Indian investigations, which are not essential for the transferability of the results. Excessive extraction of natural sand (fNA) leads to serious ecological and economic problems, for example, changing the water direction, coastal erosion, building dead-end diversions and holes  and, furto 12 kg ,5,6,7,8.As mentioned before, the substitution of natural sand in concrete production has many advantages. However, it is necessary to mention that the wider use of fine recycled aggregate (fRA) also brings challenges. First, there is high variability of the physical and chemical properties of fRA due to the presence of soil, dust, clay, glass, wood, plastics, etc. Assuming that the pure waste material, concrete or masonry, without unwanted impurities is used for preparing fRA as an aggregate for concrete, the decline of concrete properties becomes acceptable. Even so, if the impurities are removed, there is still a wide range of properties, mostly due to the composition of the parent material, which are dependent on local materials, construction, demolition, and recycling processes’ habits. The fRA particle shape, gradation, specific surface area, and chemical composition of the parent material are the important aspects that lead to inconsistencies in the mechanical properties and durability of mortars and concrete prepared using fRA.The fRA (<4 mm) can be divided into three types: (1) fine recycled concrete aggregate (fRCA), which originates from waste concrete; (2) fine recycled masonry aggregate (fRMA), which originates from masonry; and (3) fine mixed recycled aggregate (fMRA), which originates from the construction and demolition waste (CDW).fRCA is produced by crushing waste concrete from CDW ,10,11,12fRMA originates from waste masonry and the main constituents are red clay bricks, ceramic, mortar, plaster, and, very often, also waste concrete with aggregate particles and cement mortar. Similarly, with fRCA, the fRMA is more porous compared to natural sand and has a higher water absorption. Generally, the porosity and water absorption of fRMA are higher compared to those of fRCA ,25,26,27For these mentioned reasons, the applications of various fRAs in the concrete industry, due to the unknown origin and properties of parent material, upscaling, and lack of guidelines for testing essential properties such as water absorption influencing the workability and effective water-to-cement ratio, make the practical application extremely challenging.In contrast to the utilization of coarse fraction for recycled concrete aggregate (RCA) as a substitution of aggregate in concrete, where the investigation has been clearly concluded with the description of all negative effects on the properties of fresh and hardened concrete and durability, such as high porosity and consequently high water absorption and weak interfacial transition zones ,28,29,30The main goal of this study is to evaluate the possibilities of using fRCA as a substitute for natural sand in concrete with an inclusive approach of partnerships between two different regions by following the same research approach. Furthermore, the transferability of practices and experiences is verified. The results, as mentioned in previous studies, of the influence of the recycling technology and properties of the parent concrete on fRA are essential for its future use. For these reasons, the basic material properties of fRA and fine recycled aggregate concrete (fRAC) were examined and compared to find differences in this investigation.The use of fRCA ,39,40,41Nedeljkovic et al.  reviewedEvangelista and de Brito ,37 studiGeng et al.  investigFan et al.  studied Khatib  studied In the case of the Czech Republic, the use of recycled aggregate from construction and demolition waste became increasingly desirable over the last few years. The primary reason is the decreasing amount of available natural resources, which is mostly caused by mining closure and restrictions on the opening of new or expansion of existing quarries, which in turn has escalated the price of natural aggregates. Secondly, owing to the interest in promoting circular practices, demolition and construction companies are increasingly approaching the sorting of individual waste, such as waste concrete and masonry, for on-site use, especially for landscaping. This approach, although not ideal, is satisfactory in many respects, especially if landscaping is necessary on-site. For this reason, the amount of mineral CDW  reported as received in a landfill or at a recycling center is relatively small, approximately 4.6 million tonnes per year (2020), which is approximately 450 kg per person, and year-on-year has a declining trend. This means that the amount of CDW reported in landfills and recycling centers is decreasing. On the contrary, the extraction of primary raw materials for the construction industry is still growing and is around 72 million tonnes. For comparison, the extraction of primary raw materials in 2015 was 6400 million kg per person per year, which rose to 6700 million kg per person per year by 2020. As is evident from the statistics compiled annually by the Czech Statistical Office , even if2 of the built-up area and that from the demolition of constructed structures is around 300–500 kg/m2 of the built-up area. In order to tackle the problem of CDW, recycling plants are set up in a few cities in India. There are four operational recycling plants in India [In India, the management and reuse of CDW is a prime concern. A study conducted by the Building Material and Technology Promotion Council , New Delin India ; the firin India . As per in India . SimilarIn total, 13 concrete mixtures (7 from the Czech part and 6 from the Indian part) were manufactured and examined to verify the possible replacement of natural sand by fRA. Two concrete strength classes were chosen for comparison: the concrete class with compressive strength of 20 MPa for plain concrete and the concrete class with compressive strength of 30 MPa for structural (reinforced) concrete. All concrete mixtures contained coarse natural aggregate and recycled fine aggregate. Natural river sand and crushed stone sand (India) in these mixtures were replaced by fine recycled aggregate (fRA) originating from the CDW from waste concrete (fRCA) by both the India and Czech teams and waste masonry (fRMA) by the Czech team. The basic physical properties , mechanical properties , and durability (freeze–thaw resistance and carbonation resistance) of concrete were verified and compared.3 and water absorption (WA) ranges from 12% to 15% [3 and WA varies between 2.38% and 19.3% [3 and WA for the natural fine aggregate ranged between 0.15 and 4.1%. In conclusion, fRMA and fRCA have lower densities than natural sand [As described above, the measurement method of fRA’s density and water absorption has not yet been established, leading to the high differences between published results. Previous studies have reported that the dry density of fRMA ranges from 2000 to 2500 kg/m% to 15% ,36,61,62nd 19.3% ,65,66,67ral sand . For thiThis study presents the possibility of replacing the whole fine fraction of natural sand (fNA) with fine recycled aggregate (fRA). The Czech team used one type of coarse NA (NA1 fractions 4–8 mm and 8–16 mm) and natural mined sand (fNA1 0–4 mm), two types of fRCA, and one type of fRMA (fractions 0–4 mm), as shown in 3 to 2430 kg/m3, where the decline of density in comparison with NA is up to 20%, corresponding with the results of previous studies [The properties of NA and RA fractions used in this study by both the working teams are given in  studies ,65,66,67 studies  due to d3 for the mixtures labelled I and III, 300 kg/m3 for II, and 320 kg/m3 for IV. The mixture proportions are given in The 13 concrete mixtures were manufactured for laboratory verification of the properties. The cement CEM I 42.5 R content was 260 kg/mThe Bolomey particle size distribution curve was used for optimizing the skeleton of the concrete mixtures. The mixing procedure used by the Czech team was similar to that reported by Evangelista and de Brito . Here, a2) and long-term strength development (at the ages of 90 and 180 days) were tested.The physical, mechanical, and durability properties were examined by both teams. The dimensions of specimens and testing standards used in the experimental work are shown in The water absorption capacity by immersion, which describes the transport behavior of the material, was obtained on 100 × 100 × 100 mm cube specimens. The specimens were immersed in a water chamber until constant weight and thereafter dried in an oven at 105 ± 2 °C until constant weight. The sorptivity of the concrete specimens of size 100 × 100 × 100 mm with time was determined by conditioning the samples at 105 °C in an oven until their weight stabilized. The specimens were placed on a support device by exposing one of the surfaces to water. The change in mass of specimens was noted at intervals of 0, 1, 10, 30, 60, 120, 240, 1440, 2160, and 4320 min. The slope of the line obtained by plotting absorption against the square root of time gives the sorptivity of the concrete as per ASTM C1585-20.Prismatic samples of 100 × 100 × 400 mm and 100 × 100 × 500 mm, respectively, cured in water for 28 days were used for assessing the freeze–thaw resistance. The frost resistance was measured according to ČSN 73 1322 (1969) and ASTM C666/C666M-15 (2015) for the Czech team and Indian teams, respectively. Both the teams followed testing by cyclic freezing and thawing at temperatures ranging from −15 °C to +20 °C, where one cycle takes 4 h of freezing and 2 h of thawing. The Czech specimens were subjected to rapid freezing in air and thawing in water and the Indian specimens were subjected to rapid freezing and thawing in water as per ASTM C666/C666M-15 (2015) procedure A. The freeze–thaw resistance was observed for a total of 100 cycles. The measuring of the dynamic modulus of elasticity was performed by the Czech team according to EN 12504-4 (2005) after each phase and by the Indian team according to BIS 13311-1 (1992) after the completion of a total of 100 cycles. The flexural strength was tested by both teams after 100 cycles according to EN 12390-5 (2009) and BIS 516 (1956), respectively, by the Czech and Indian teams.2 atmosphere CO2CELL (MMM group) with a concentration of CO2 3.0 ± 0.2%. This test has been prepossessed by the standard ČSN EN 12390-12. Nevertheless, the testing process has been slightly modified and does not fully comply with the standard regulation. The pH drop in the concrete due to CO2 was evaluated using the phenolphthalein indication method. In contrast, the accelerated CO2 ageing test by the Indian team was performed on samples of different dimensions and in a slightly different way. The depth of carbonation in the concrete cube of size 100 × 100 × 100 mm was tested as per RILEM CPC-18. The samples were cut into four pieces of size 50 × 50 × 100 mm and air-dried for 14 days. The longitudinal sides were coated with epoxy paint and kept in a carbonation chamber at a condition of 3 ± 0.1% CO2, 25 ± 2 °C, and 60 ± 5% relative humidity for 28 days. The depth of carbonation was determined by spraying the phenolphthalein indicator on the split surface of the sample.Prismatic samples of 100 × 100 × 400 mm were stored in a constant laboratory environment for measuring the carbonation resistance. Half of the samples (100 × 100 × 200 mm) were placed for 28 days in laboratory equipment with COIn this section, the results of physical, mechanical, and durability properties examined by both the research groups are presented and compared.As reported in previous studies ,70, the Although previous studies have reported a significant increase in capillary absorption from 46% to 95% for 100% fRCAC , this waThe results of compressive strength, which is the key mechanical property of concrete, are presented in At 28 days, the strength of concrete fRCAC3 IB was observed to decrease with respect to the two controls, by 11% with respect to NAC IB and 26% with respect to CSSC IB. The strength of fRCAC3 IIB concrete was found to reduce by 29% in comparison with control NAC IIB and 29% with respect to CSSC IIB. The compressive strength of both concrete strength classes with fRMA slightly decreased  compared to the control mix. Furthermore, the development of the compressive strength over time shows a higher rising of fRAC than control concrete.The decrease in strength and differences between each mixture are probably caused by the presence of an undefined amount of adhered mortar and the amount of additional water to compensate for the higher water absorption and the ability of fRA to soak water during mixing. As previously written, the amount of cement mortar is influenced by the parent concrete and the recycling procedure . In thisThe development of compressive strength was measured at 28, 90, and 180 days by the Czech team and 7, 28, and 90 days by the Indian team, respectively. The results show a lower increase for fRA mixtures in comparison with the references. The increase of the control concrete was maximally 25% at 180 days; however, in the case of fRA, the maximal increase was 16% see .Past studies have reported a decrease in the flexural strength of fRCA concrete/mortar with the increase in the fRCA content ,76. The The comparison of the flexural strength of concrete mixtures at 28 days is presented in The static modulus of elasticity is the key characteristic for assessing the behavior of reinforced concrete structural elements. Past results of concrete containing coarse RA have reported that, among all the concrete properties, the modulus of elasticity was degraded the highest. The reductions in the static moduli of concretes where natural sand was replaced by fRA range between 9.5% and 17% ,79. WangThe static and dynamic elastic moduli at 28 days of concrete prepared by the Czech and Indian teams, respectively is shown on The most important factor that affects durability is concrete permeability, which is studied by the oxygen and water permeability test, water absorption by immersion, and capillarity ,86,87,88The frost resistance coefficient is according to the Czech Standard established from the flexural strength and dynamic elastic modulus before and after freezing and thawing cycles, respectively.In the case of freeze–thaw resistance, the positive effect of fRA in the mixture has been found. This phenomenon is caused by the higher porosity of the fRCA, which can provide better hydraulic pressure dissipation. The negative influence of the affecting freezing and thawing could be observed on the fRAC surface, due to the less-resistant mortar, however, without loss of mechanical properties ,78,89. T2 into the concrete, probably caused by the high porosity fRMA. The increase in carbonation depth was 155% for fRMAC IA and 123% for fRMAC IIA. In the case of the Indian concrete mixtures, fRCAC3 IB was observed to have a higher depth of carbonation by 32% and 23% compared with NAC IB and CSSC IB, respectively. A significant increase in carbonation depth was observed in fRCAC3 IIB with respect to NAC IIB and CSSC IIB by 126% and 112%, respectively. The increase in carbonation depth may be attributed to the presence of high mortar content and more pores present in the fRCA concrete. Similar observations were found by [Carbonation depth determines the quality of concrete’s protective cover over steel reinforcement bars. A poor carbonation resistance is bound to affect the service life of reinforced concrete structural elements . In prevfound by ,53,85. Ofound by ,92, the In this study, the possibility of full replacement of natural sand in concrete by fine recycled aggregate was experimentally verified and discussed. This study was designed and implemented in the Czech Republic and India with the same research approach. The properties of fRA were examined by the validation of the physical and mechanical properties and durability of concrete containing fRA with a comparison between two different regions. The following conclusions are drawn.Differences were found in the properties of reclaimed sand originating from construction and demolition waste in two regions, which are probably caused by the parent concrete and differences in the recycling process. Moreover, the properties of concrete containing fRA slightly vary between the compared two regions, however, in both cases, the decline of properties in comparison with ordinary concrete is not limiting for finding satisfactory utilization.The density of fRA and, consequently, of fRAC decreases slightly compared with the natural sand and control mix, respectively. The water absorption of fRA and, consequently, of fRAC increases significantly compared to the natural sand control and control mix, respectively. On the contrary, the capillary water absorption decreases.The compressive strength mostly shows a slight decline; however, considering that the natural sand was fully replaced. For this reason, for future use of this material, the decline of compressive strength may be considered before a mixture design. The effect of the decline of the flexural strength is similar to compressive strength.In the case of modulus of elasticity, the highest decline in properties was found, which corresponds to previous studies, showing that the elastic modulus is the most decreased mechanical property of concrete with substitution by recycled aggregate in general. The static modulus of elasticity is the key characteristic of the material for the behavior of reinforced concrete structural elements because of its lower deflection of beams and slabs. For this reason, it is recommended to verify the strength and other technical requirements prior to using fRA as a full replacement of natural sand in reinforced concrete structures.In contrast, durability properties were not worsened significantly with fRA. The freeze–thaw resistance was completely satisfactory, and, furthermore, the carbonation resistance, although slightly affected, was not essential in terms of structural use since the concrete cover is usually 2 mm or higher. However, due to the significant decline of the modulus of elasticity, the use of fRAC as a complete replacement of natural sand for reinforcement concrete structures may need attention.The novelty of this study was the comparison of the properties of fRA and fRAC in different regions in accord with SDG 17, which encourages partnerships to achieve the goal. The main objective of this study was to verify the transferability of practices and experiences of the substitution of sand in concrete by comparison of the results in two different regions with the same research approach. As mentioned in previous studies, the recycling technology and properties of parent concrete influence the properties of fRA, therefore, the material properties of fRA and fRAC were examined and compared in this investigation. Although minor differences in material properties were found between the two regions, the differences were not essential for future utilization, which will be more suitable for the complete replacement of sand in plain concrete structural elements, such as foundation structures, cement, concrete screed, etc., due to the local standards, the availability of the material, and the results of this investigation. Overall, this work represents the efforts in the direction of attaining a circular economy and thereby addressing the SDG 12.


To evaluate clinicopathological features and survival outcomes of unilocular cystic renal cell carcinoma (ucRCC) compared with purely solid renal cell carcinoma (sRCC), and to evaluate the oncologic aggressiveness of ucRCC. The relevant data of 957 patients with sporadic unilateral renal cell carcinoma (RCC) underwent surgical treatment in 2 institutions from Jan 2014 to Oct 2018 were obtained. We excluded multilocular cystic renal neoplasm of low malignant potential (MCRNLMP), RCC with multilocular cysts and necrotic RCC. 74 ucRCCs were identified by pathology reports. We performed propensity score matching (PSM) and eventually selected 144 sRCCs. The clinicopathological features and survival outcomes were compared properly. After PSM, age, BMI, Charlson Comorbidity Index, and postoperative Chronic Kidney Disease grade were not significantly different. Both overall survival and progression-free survival of ucRCC were significantly better than sRCC by the log-rank test. Twenty-five cases of sRCCs were in the pT3 or pT4 stage, while no pT3 or pT4 tumors were found in ucRCCs. Fuhrman grade and lymphatic metastasis were found to be significant prognostic factors for the overall survival of ucRCC. Unilocular cystic RCC has a lower Fuhrman grade and pathological stage and a better prognosis compared with solid RCC. Patients with ucRCC still probably have lymphatic metastasis at surgery and may have postoperative metastasis, which is different from MCRNLMP. We recommend that the diagnosis of ucRCC should be reflected in pathology report. Different subtype of cystic RCC should be taken into consideration in counseling and management. Some studies have also found that most of MCRNLMP have Von Hippel-Lindau (VHL) mutations and 3p deletions, which suggests that they are related to clear cell renal cell carcinoma at the molecular level6. Compared with solid renal cell carcinoma (sRCC), the MCRNLMP has a very distinctive histology and an excellent prognosis. In terms of tumor morphology, we can classify renal cell carcinoma (RCC) into the following types: MCRNLMP; RCC with a multilocular cystic component (not meeting the diagnosis of MCRNLMP); unilocular cRCC and purely solid RCC.In 2016, the World Health Organization redefined multilocular cystic renal cell carcinoma, a subtype of cRCC, as the multilocular cystic renal neoplasm of low malignant potential (MCRNLMP) based on the excellent prognosis wherein more than 200 patients were followed up for more than 5 years without recurrence or metastasis5. Many previous studies failed to identify it separately, but classified MCRNLMP together with all other types as the cRCC, and investigated their outcomes10.MCRNLMP is a morphology and prognosis distinctive subtype of cRCC and accounts for only about 1% of RCC, while the whole cRCC accounts for 15%10, other types of cRCC actually do not have as good prognosis as MCRNLMP12. In that way, those previous studies have made incorrect judgments on the prognosis of many other types of cRCC besides MCRNLMP, especially unilocular cystic renal cell carcinoma (ucRCC). Few studies have previously classified this type of tumors, which is completely different from MCRNLMP, into a separate category for survival research.Although those studies have discovered that the cystic morphology of RCC is associated with a good prognosisIn this review, we intend to analyze the clinicopathological data of ucRCC and compare it with those of purely solid RCC to improve clinician’s understanding of this subtype of cRCC and provide new perspective for clinical management decisions and follow-up.13, and the number of deaths in RCC with cystic components was relatively small in our study. Therefore, we were not able to select a reliable cut off for unilocular cRCC but included all RCC with obvious single cysts on preoperative CT imaging and confirmed by pathology reports as non-necrotic in group A. Meanwhile, we used Stata ® to perform 1:2 propensity score matching  by age, BMI, Charlson Comorbidity Index (CCI), and postoperative Chronic Kidney Disease (CKD) grade  using the abbreviated Modification of Diet Renal Disease Study Group in 761 cases of pathologic confirmed solid RCC, and randomly identified 148 patients. After excluding 4 patients who had distant metastases at surgery and underwent cytoreductive surgery, 144 cases were included in group B for comparison.The date of 993 patients was obtained from January 2014 to October 2018 at two different institutions with approval from Ethics Committee of Zhengzhou University. We excluded 16 cases of multifocal RCC (including 6 cases of VHL syndrome), 20 cases with incomplete preoperative images, 12 cases of MCRNLMP, 62 cases of RCC with multilocular cystic component (not meeting the diagnosis of MCRNLMP), 48 cases with necrotic cysts confirmed by surgical pathology (including 9 cases misdiagnosed as true cysts by radiologists). Finally, 835 patients were included in this study, among which 74 cases were identified as unilocular non-necrotic cRCC by surgical pathology reports and placed in group A  and imaging data was reviewed by experienced radiologists unaware of the clinical data. The record content included: R.E.N.A.L. score and Bosniak classification of the lesions, the respective volume of the entire tumor and cystic components calculated by computer software multiplying the area of all sections by the thickness of each layer, and tumor diameter that was the average of the diameter on each axis of the tumor. Although our study relied on pathology results to diagnose unilocular cRCC, we also required radiologists to judge the nature of cysts when reviewing CT. The criteria radiologists applied to determine the true cystic component were: 1) The CT-value in the capsule being less than 20 Hu and unmixed density at routine scan. 2) There was no obvious enhancement in the capsule during the cortical phase (≤ 40Hu).p value less than 0.1 in univariate regression analysis were included in multivariate regression analysis, and all other results were considered statistically significant only with p < 0.05.All statistical analyses were conducted with SPSS®, version 26.0. Continuous variables were presented as mean ± SD and compared by the t test. Categorical variables were described by frequencies with proportions and compared by chi-square and Wilcoxon rank sum test as appropriate. The primary end points were overall survival (OS) and progression-free survival (PFS). The median follow-up time is 4.57 years (1.25–6.74). The overall survival (OS) and progression-free (PFS) were estimated by the Kaplan–Meier curves, and differences between curves were assessed with log rank test. Moreover, cox proportional hazards models of univariate and multivariate analyses were applied to identify factors associated with overall survival for ucRCC, expressed using hazard ratio (HR), 95% confidence interval (95% CI). The factors with All methods in this study involving human participants were performed in accordance with the ethical standards of the institutional research committee and were permitted by Ethics Committee of Zhengzhou University, with no living animals involved. This study is a retrospective study, Ethics Committee of Zhengzhou University therefore waived the informed consent.This study is a review of existing data and does not involve any studies with human participants or animals performed by other authors.3 respectively, while those in group B were 4.55 ± 0.96 cm and 105.88 ± 67.20 cm3 respectively, and there with no significant difference . In terms of Fuhrman grade, only 2 cases in group A were G3, and there were no G4 tumors. However, G3 and G4 tumors in group B accounted for 36.2%, and the difference between 2 groups was significant (p < 0.001). The decision to perform lymphadenectomy for all patients was uniformly based on preoperative CT findings of enlarged lymph nodes. In group A, 5 patients underwent lymphadenectomy and 3 of them were pathologically confirmed to have lymphatic metastasis. In group B, 16 patients underwent lymphadenectomy, of which 9 had confirmed lymphatic metastasis. Sixty-six (89.2%) cases of group A were in the pT1 stage and the remaining 8 (10.8%) were in the pT2 stage. While no pT3 or pT4 tumors were found in group A. Meanwhile, 21 (14.6%) cases in group B were in the pT3 or pT4 stage. The difference between the 2 groups is statistically significant (p = 0.006). The most common histology type in the 2 groups was clear cell carcinoma  cases of papillary carcinoma in group A (12.2%) than in group B (2.8%). And a higher proportion of type I papillary RCC in group A compared to matched and total sRCC group was identified, though not statistically significant (p = 0.217). None of the patients in the 2 groups who underwent partial nephrectomy showed positive margins in the pathology reports. We also noticed that 26 (35.1%) unilocular cysts in group A had irregularly thickened inner walls greater than 2 mm and 11 (14.9%) cysts had irregular internal structures  and progression-free survival (p = 0.040) of the unilocular cRCC were significantly better than the purely solid RCC by the log-rank test. Fourteen patients in group B died and 12 patients experienced recurrence or metastasis. A patient of group B was reported to have local recurrence 2 years post-partial nephrectomy and was treated with radical nephrectomy. Lumbar metastasis was found 2 years later and currently VEGFR inhibitors treatment is being administered. In group A, only 1 patient died of lung metastasis after radical nephrectomy. Meanwhile, of the 12 MCRNLMP patients in our original cohort, except one patient lost to follow-up, the remaining 11 patients are alive and have no recurrence or metastasis according to our recommended annual physical examination. Furthermore, we applied the Cox proportional hazards regression model to perform univariate and multivariate regression analysis of survival data  intrinsic multiloculated growth; (2) intrinsic unilocular growth; (3) cystic necrosis; (4) origin from the epithelial lining of a preexisting simple cyst15.However, this classification has not been widely accepted by pathologists. Cystic necrosis, for example, is actually caused by the imbalance of tumor growth and insufficient blood supply. It is not only found in various pathological types of RCC, but also common in other malignant tumors. The existence of malignant transformation of simple cysts is still debatable and there are rare related reports. Therefore, many pathologists believe that the above two subtype should be excluded from the subcategories of cRCC, which means that cRCC should only include the unilocular cystic and the multilocular cystic morphologically16. Although unilocular cRCC has been reflected in some studies, there is no specific study with a large sample size. Meanwhile, many studies did not emphasize the classification of cRCC subtype. As a result, the two concepts of continuously redefined “MCRNLMP” and “cystic renal cell carcinoma” have been implemented without coming into conflict, which has caused a lot of confusion for researchers and clinicians.With the continuous increase of relevant researches, multilocular cRCC has gradually become the focus. Both the 2004 revised and 2016 WHO guidelines only defined multilocular cRCC without mentioning unilocular cRCC17. This is consistent with our findings. Group A had significantly more papillary RCC than group B, which is somewhat inconsistent with the findings of previous studies in that, the main histology of unilocular cRCC in our study is clear cell carcinoma, not papillary RCC. This discrepancy may be due to the small number of samples used in previous studies17. At the same time, Hartman also noticed that a few cysts discovered on CT imaging are actually extensive necrosis and tumor necrosis is one of the negative indicators in many prognostic models of RCC18. In this study, we defined unilocular cRCC, which excludes necrotic cysts through surgical pathology. However, it is worth noting that it is not reliable to determine whether the cystic component is a true cyst or a necrotic cyst only though preoperative CT imaging. For instance, radiologists with more than 3 years of work experience reviewed the imaging data in this study, but among the 83 cases initially judged as true cysts, 9 cases (11%) were still pathologically confirmed as necrotic cysts. Some studies have shown that MRI may be more advantageous than CT in the differential diagnosis of true cysts19 but due to lack of relevant imaging data, we did not investigate that.In some studies, it was found that there were many papillary RCC in unilocular cRCC3. Therefore, its definition is changed from “cancer” to “neoplasm”. However, of the 74 cases of unilocular cRCC in our study, 1 patient died of metastasis of the RCC. Although no distant metastasis was found at the time of diagnosis, 3 cases of lymphatic metastasis were found in surgical pathology of lymphadenectomy. It can be seen that although the unilocular cRCC is less malignant than the purely solid RCC, its prognosis is not as excellent as that of the MCRNLMP defined by the WHO in 2016.Numerous studies on MCRNLMP have shown that the malignancy of this type of tumor is low, and no recurrence or metastasis have been reported so farIn this study, we did not set the cut off of the cystic component for unilocular cRCC like other studies but included all RCC with true cystic components. But we found that the cystic proportion of 1 case who dead of RCC in group A was not low (52%), and the cystic proportion of 1 case who had lymphatic metastasis at surgery in group A also reached 78%. We believe that unilocular cRCC even with a high cystic proportion also probably had lymphatic metastasis at the time of diagnosis and recurrence after surgery. Although the presence of cystic components in RCC might predict lower malignant potential, the correlation between high cystic proportion and the mostly indolent outcome has not been fully proven, studies with larger sample sizes are needed in the future.10. Given that the MCRNLMP is a rare type and was differently defined in previous studies, the true incidence of MCRNLMP was uncertain. According to some recent studies, it can be inferred that it accounts for roughly 1% of RCC5, while cRCC account for 15%21. Defining the MCRNLMP as being similar with all other types of cRCC and making survival comparison with solid RCC certainly will mask the relatively poor prognosis and relatively high malignancy of other types of cRCC such as the unilocular cRCC. As a result, when making clinical decisions, surgeons may underestimate the malignancy of cRCC other than MCRNLMP. It is a bot puzzling that although the pathological stage and Fuhrman grade of 74 unilocular cRCC cases are relatively low, 3 cases (4.1%) still have lymphatic metastasis at surgery and the difference with that of solid RCC (6.2%) is not significant (p = 0.501). We speculated that this may be due to the relatively small sample size. It may also be because that 3 cases of tumors were large in size. The average maximum diameter of the tumors in group A was 4.45 ± 1.10 cm, while that of 3 cases with lymphatic metastasis were 6.57 cm, 6.37 cm, and 6.63 cm, respectively.In previous studies conducted before and after 2016, MCRNLMP was not clearly distinguished from other types of cystic RCC12. Therefore, the clinical treatment and follow-up decisions of them should be made pertinently. Many studies have pointed out that for MCRNLMP, nephron sparing method should be used as much as possible23. In view of the findings of this study, we recommend that unilocular cRCC should also be treated with nephron sparing approaches when feasible. Radical nephrectomy is still needed when the tumor is large, and regional lymph nodes should be removed if the preoperative imaging shows the sign of enlarged lymph nodes. However, our proposal and specific implementation plan need to be confirmed by further prospective studies.The excellent prognosis of MCRNLMP may suggest that the existence of the cystic component of renal carcinoma is somehow related to a favorable prognosis. According to existing researches, it can be seen that the prognosis of MCRNLMP, unilocular cRCC, and solid RCC shows a decreasing trend24.For most cases, the diagnosis of different subtype of cRCC based on imaging data ultimately needs to be confirmed by postoperative pathology, which means that clinical decisions on nephron sparing or radical approaches have always been made. Clarifying that the tumor belongs to a specific subtype of cRCC can only be used as a guide for postoperative follow-up or retrieval reoperation. Therefore, it is particular important to judge different subtype by preoperative imaging, especially to identify MCRNLMP and necrotic cysts. Several relevant studies published may help on this issue, but there is still room for improvement in the accuracy of diagnosis8.There are several limitations to our study. (1). This study is retrospective in nature; the pathological features were summarized based on the surgical pathology reports. We were unable to personally obtain tumor specimens for further analysis, such as cyst fluid properties, more comprehensive immunohistochemistry, etc. (2). As a result of the intention to investigate unilocular cRCCs and the total number and the number of cancer-specific deaths in group A were small, the optimistic cut off of cyst/solid ratio related to prognosis could not be calculated. (3). Twenty patients were excluded due to incomplete imaging data, which may have caused selection bias to the outcomes. (4). In order to eliminate confounders, we performed PSM in 761 solid RCC cases, and eventually enrolled 144 cases in the control group. Therefore, when performing Cox regression, the Goodness of Fit may be not ideal enough. Although the PSM method adopted to select matching objects is random, the solid RCC group still has the possibility of underrepresentation. However, the characteristics of solid RCC in other similar studies with larger sample size can be corroboratedWe reported the first large series of long-term survival of unilocular cRCC. Compared with purely solid RCC, unilocular cRCC have a lower Fuhrman grade and pathological stage and a better prognosis but some patients still probably have lymphatic metastasis at the time of diagnosis and may have postoperative relapse, which is different from that in MCRNLMP. The presence of unilocular cyst should be documented in the pathology report like the multilocular one, and when making clinical decisions and follow-up plans for cRCC, the different subtype of cRCC could be taken into consideration as a factor.