According to recent statistics, there has been a rapid growth of breast cancer in developing countries. Thus, early detection is essential. This study is based on the perception of people in the Northeast of Iran regarding breast cancer screening.In a cross-sectional study, 1469 women were selected randomly in the period from April to November 2016. The study population consisted of women or their companions referring to outpatient clinics or people in public urban areas who filled out a breast cancer screening questionnaire in an interview.The patients’ age was in the range of 14 to 84 years (mean = 38.8). More than 84% of interviewees were not informed of breast cancer and screening tests. The main reasons mentioned by patients for their failure to do screening tests was ‘absence of any symptom or problem’ and ‘they did not think it was necessary’.There was not a significant difference between income level, marital status and knowledge of people about breast cancer screening tests (P > 0.05). However, employment, education level and family history had a positive effect on people’s awareness of breast cancer and its screening tests (P < 0.05).The lack of knowledge in people from low socio-economic classes was the main barrier to breast cancer screening. In this regard, organizing training programs by physicians and the media can help raise screening rates. Breast cancer is the most prevalent type of cancer among women in Iran and other parts of the world . It is sSome studies have shown that raising awareness of women and modifying their behaviour can precipitate the stage of disease detection and therefore change the quality of life and survival rate of patients (which are directly related to the stage of cancer detection).Several studies have revealed that the age of breast cancer diagnosis in Iran, which is nearly 10 years younger than other countries, is between 40 and 50 years . KnowledThis is a cross-sectional study in which 1,469 patients referring to outpatient clinics and people in public urban areas, who were aged above 14, were interviewed and asked to fill out the study questionnaire in the period from April to November 2016.Interviews were performed by four trained questioners. Questionnaires consisted of demographic data, knowledge of symptoms, risk factors and screening tests for breast cancer as well as the reasons for failing to do these tests. The ways in which participants learned about screening tests were also investigated.Risk factors of breast cancer assessed in the questionnaire, which were based on the NCC 2016 guidelines, consisted of 17 items: (1) excessive alcohol consumption; (2) smoking; (3) obesity; (4) family history and genetics; (5) chest radiation before the age of 30; (6) sedentary life; (7) number of pregnancies; (8) pregnancy age; (9) number of breastfeeding; (10) breastfeeding age; (11) high-fat diet; (12) dense breast; (13) menstrual age; (14) contraceptive use (15) family history; (16) patient age and (17) hormone therapy [Symptoms of breast cancer included six items: (1) painless mass; (2) premenstrual breast nodules; (3) sharp pain in the nipple; (4) breast asymmetry; (5) galactorrhea after breastfeeding and (6) blood discharge from the nipple .In our study, women’s knowledge of breast cancer screening tests was also evaluated: (1) self-assessment; (2) ultrasonic; (3) mammography and (4) MRI.Since the purpose of the study was to evaluate women’s knowledge of breast cancer screening tests, patients with a history of breast cancer or related diseases were excluded. After interviews, free training about the use of screening tests was offered to participants.The reliability of the questionnaire was evaluated by Cronbach’s alpha (a = 86.4%). The validity of the questionnaire was assessed using constructs of health belief model as a guide.Descriptive and analytical statistical analyses were performed by SPSS Statistics V21. The level of awareness was compared across the level of education, marital status, income and employment using Chi-square and ANOVA for quantitative data such as age and knowledge. The scoring of different sections of the questionnaire was conducted as shown in About 1,469 questionnaires were completed by women in the age range of 14–82 years . Demographic information of patients is given in In most patients with a family history, breast cancer had already appeared in a relative such as an aunt (2.9%) or the mother (2.6%). Overall, more than 84% were not well informed about breast cancer and its screening tests. Among these, as shown in p = 0.029), working status of women (p = 0.0001), educational level (p = 0.0001) and women’s awareness of breast cancer risk factors. The results showed that employment and level of education had a positive effect on knowledge and awareness of women about breast cancer and its screening tests. Moreover, the results indicated a significant disparity between income status (p = 0.972), marital status (p = 0.808) and women’s knowledge of breast cancer and screening tests.More than 26% of participants stated that their failure to do screening tests was mainly rooted in ‘the absence of any symptom or problem’ and 17.6% said that ‘they did not think it was necessary’. A large number of participants (29.1%) believed that doctors could be especially helpful in informing the community about screening tests for breast cancer and 24.1% stated that the Internet and social networks were a good means of raising public awareness. 19.3% of women also contended that mass media could play a significant role in this regard. Data analysis showed a significant relationship between variables such as family history of breast cancer (p = 0.165) and symptoms of breast cancer (p = 0.248) were not significantly correlated with age, but older women were more aware of the type of screening tests for breast cancer. Thus, this difference was significant at different ages (p = 0.009).The results showed that women’s knowledge of risk factors (The study found that more than 84% of the participants were not well aware of risk factors, symptoms or screening tests for breast cancer, and more than 59% had never taken any screening tests before. This figure is even lower than the one reported in the United States, according to which about 72.6% of women aged 50–74 years have breast cancer mammography screening tests done every two years, though it is still below the target rate .et al [et al [et al [This study revealed that one of the main challenges facing the use of screening tests was a lack of knowledge about the necessity and importance of doing these tests, with few people pointing to the costs of tests as an impeding factor. However, Pourfarzi et al  reportedl [et al  and Shaml [et al .A study in Saudi Arabia suggested that despite subsidies allocated to screening tests, so that women could access these tests free of charge, they were not well received by women . These cIn the same line of research, Crawford stated that social and cultural demographic factors should also be considered in planning relevant interventions . It has As such, greater attention should be paid to breast cancer prevention and screening. In this regard, widespread propagation and raising public awareness about screening tests should be high on the agenda of healthcare systems. The results of this study, consistent with the literature, suggest that informing people through the media and physicians, as the most reliable sources of information, can be very helpful .One limitation of the present study was that subjects filling out the questionnaire were chosen from both the hospital environment and public places, and those in the hospital were often more aware of breast cancer than were the other subjects, which can cause heterogeneity in the study population. On the other hand, since questionnaires were completed by questioners and they provided a varied extent of explanation to participants, it may have caused bias. It is suggested that other studies be carried out in light of the above factors.Lack of knowledge, especially in the low socio-economic stratas of society, is one of the most important barriers to screening tests. Therefore, organising training programs with the cooperation of doctors and the media is crucial to improve the uptake of screening tests.In a relatively developed country like Iran with a solid health care system, the training offered by family doctors could be a helpful strategy for promoting breast cancer screening based on national and international guidelines for ultrasound, and if necessary, mammography tests.


Decision analysis study that incorporates patient preferences and probability estimates to investigate the impact of women’s preferences for referral or an alternative strategy of watchful waiting if faced with symptoms that could be due to breast cancer.Community-based study.Asymptomatic women aged 30–60 years.Participants were presented with 11 health scenarios that represent the possible consequences of symptomatic breast problems. Participants were asked the risk of death that they were willing to take in order to avoid the health scenario using the standard gamble utility method. This process was repeated for all 11 health scenarios. Formal decision analysis for the preferred individual decision was then estimated for each participant.The preferred diagnostic strategy was either watchful waiting or referral to a breast clinic. Sensitivity analysis was used to examine how each varied according to changes in the probabilities of the health scenarios.A total of 35 participants completed the interviews, with a median age 41 years (IQR 35–47 years). The majority of the study sample was employed , with a third-level (university) education  and with knowledge of someone with breast cancer . When individual preferences were accounted for, 25 (71.4%) patients preferred watchful waiting to referral for triple assessment as their preferred initial diagnostic strategy. Sensitivity analysis shows that referral for triple assessment becomes the dominant strategy at the upper probability estimate (18%) of breast cancer in the community.Watchful waiting is an acceptable strategy for most women who present to their general practitioner (GP) with breast symptoms. These findings suggest that current referral guidelines should take more explicit account of women’s preferences in relation to their GPs initial management strategy. Strength of this study is that it accounts for women’s preferences in relation to a watchful waiting or immediate referral strategy when faced with symptoms that could be due to breast cancer.Weakness is that the preferences were elicited in asymptomatic women. Women with symptoms may express different preferences.The impact of eliciting preferences should be done in the context of a randomised trial of a decision aid that uses decision analysis as a form of shared decision-making for women with symptoms that could be due to breast cancer.Taking account of women’s preferences might mean that significantly fewer women would be referred to symptomatic breast clinics with a consequent saving in investigations and costs, and reducing the burden of ‘medicalisation’ in women with benign breast disease.Between 2009 and 2011, it was reported that 31% of cancers in Irish women were due to breast cancer, making it the most prevalent cancer in Irish women.Clinical prediction rules (CPRs) are clinical tools that quantify the independent impact of factors from a patient’s history, physical examination and diagnostic tests, and stratify patients according to the probability of having a target disorder.Decision analysis is a technique to aid decision-making when uncertainty exists over the balance between benefits and risks of treatment.This study used decision analysis in the form of utility assessment and folding back a decision tree. The Strengthening the Reporting of Observational Studies in Epidemiology standardised reporting guidelines were followed to ensure the standardised conduct and reporting of the research.Literature searches were conducted in medical databases such as PubMed, the Cochrane library and Web of Science to assist with the development of the decision tree and health scenarios. A specialist registrar with clinical experience in a symptomatic breast clinic was also consulted during this development phase. Following these consultations, the decision tree was constructed to portray the temporal course of the two diagnostic options . The decA total of 11 health scenarios were constructed; one for each outcome node. For this study, the standard gamble (SG) method of utility assessment was used.10.1136/bmjopen-2017-017286.supp1Supplementary file 1Probability estimates for each chance node were obtained from the medical literature.Interviews were conducted over a 6-month period in Dublin from October 2014 to April 2015. Asymptomatic women aged 30–60 years were invited to participate in the study. Participants were recruited using university staff notice boards, social media and snowball sampling. The majority of interviews were carried out in a meeting room in the research building. Some interviews were conducted in peoples’ place of work as this was more convenient for them. Written informed consent was obtained from all participants prior to participation. The interviews were conducted with a researcher present who was available to answer any questions and to obtain feedback about the interview. Prior to the interview, participants were given a baseline demographics questionnaire and a multiple-choice questionnaire to assess their knowledge of breast cancer. As this is a feasibility study for a proposed randomised controlled trial, no formal sample size was calculated. We excluded women with a current or previous history of breast cancer.A computer-based assessment programme which presented and recorded participant responses was designed. This programme incorporated an introduction, an explanation of the interview process and presentation of each clinical scenario in random order using the SG method of utility assessment. An example of the SG was included for orientation, and definitions were provided for any medical terminology used. The purpose of using a computer programme was to allow the interviewer to limit his/her interaction with each participant, standardise utility assessment and minimise interviewer bias. A pilot study was carried out and modifications made to the computer programme and utility assessment process. See online The data from the computer programme was stored with a participant ID only and saved to an encrypted password-protected desktop computer. To protect patient identity, a Microsoft Excel spreadsheet was created; containing just patient names and identification numbers, and this was stored in a secured, password-protected folder on the server and kept separate to the data from the interview.The utility for each outcome, ‘a number assigned to the quality of life a patient would attach to a particular outcome on a defined scale’,Sensitivity analysis was used to determine the robustness of the conclusion drawn from the decision tree.Standard descriptive statistics were used to summarise the sample. Results were held to be significant if they referred to statistical significance on a two-sided test evaluated at the 5% level. All analyses were performed using STATA V.13 .A total of 36 women participated, with 35 interviews completed in full. The median age of participants was 41 years (IQR 35–47 years). The demographic details of participants are described in When patient preferences were taken into account, 25 patients  preferred watchful waiting to referral as the initial diagnostic strategy. Sensitivity analysis showed that the overall preferred diagnostic strategy changed to referral when the probability of breast cancer following a period of watchful waiting increased; only 10 women favoured watchful waiting when the probability of breast cancer following a period of watchful waiting had increased to 18% . Swings In terms of two-way sensitivity analysis, more than half the participating women still preferred watchful waiting when the probability of a diagnosis of breast cancer following a period of watchful waiting was 2.25 times as high as the probability of diagnosis following RTA . This paThis study shows that a strategy of watchful waiting in women with breast symptoms in primary care could be considered as an acceptable alternative to immediate referral to a symptomatic breast clinic, but this strategy of shared decision-making using decision analysis should be tested in a randomised controlled trial. Our observational findings suggest that women’s own preferences should form an important element of the decision to refer to a symptomatic breast clinic and that these preferences should be accounted as part of a shared decision-making process. Sensitivity analysis shows that as the probability of breast cancer increases, the diagnostic strategy of referral for triple assessment dominates. Two-way sensitivity analysis shows that, across the likely probability range of breast cancer under a watchful-waiting strategy, referral for triple assessment becomes the dominant strategy once the probability of breast cancer is two and a half times more likely than under a watchful-waiting strategy.Although utility assessment has been used to evaluate the acceptability of various clinical states and treatment regimens in the breast cancer literature,Watchful waiting has also been described as a key technique for more effective management of other cancers such as prostate cancer.A qualitative study examining women’s views on overdiagnosis in breast cancer screening showed that 50% of the study population felt that they needed to make more careful personal decisions about screening and would consider watchful waiting as an alternative route if they were found to have a low-risk cancer.This study has several strengths. We used an evidence-based approach, quantifying probabilities from the literature and developing health states that incorporate the common features of breast cancer. We tested and modified the wording of the health states and the computer programme in a pilot group of participants and refined our protocol based on feedback from these participants. We tried to limit any bias caused by the interviewer by using a computer programme and providing the participant with written definitions and information. Examples of the SG were given to the participants prior to the interview, so participants had the opportunity to familiarise themselves with the method. Although the sample was relatively small, it included participants with a range of ages and knowledge of breast cancer. We acknowledge that the sample of participants is not representative of the population at large, that women were asymptomatic and that preferences may change or be different when faced with possible symptoms of breast cancer—a breast lump or nipple change. However, our results suggest that when preferences about a watchful-waiting strategy is elicited, many women are happy to adopt this approach. Based on these provisional results, we hope to develop a decision aid for women with symptomatic breast problems and test its value in a randomised controlled trial.The current referral process leads to many patients who are at low risk of breast cancer being referred to busy symptomatic breast clinics, with a risk of iatrogenic harm, increased patient anxiety and overmedicalising of a self-limiting condition. With more emphasis on the development of CPRs, it will be possible to identify and quantify each individual woman’s risk of breast cancer. A recent study derived a CPR for predicting the risk of breast cancer for women presenting to their GP with breast symptoms.This study suggests that watchful waiting may be an acceptable diagnostic strategy for women who present to their GP with breast symptoms. These findings should be validated in a larger and more comprehensive study of patient preferences in women with breast symptoms in a randomised controlled trial. Clinical practice guidelines should reflect the importance of eliciting women’s preferences for watchful waiting as an alternative to referral to a symptomatic breast clinic, particularly in women with low-risk clinical features.


Obesity is a public health epidemic and an important breast cancer risk factor. The relationship between interrelated body measurements is complex and most studies fail to account for this complexity. We identified key aspects of body size which jointly, over the life-course (since adolescence), are associated with estrogen-receptor-positive (ER+) breast cancer risk.a priori body-size phenotypes. Multivariable Cox proportional hazards models provided estimates of hazard rate ratios (HR) and 95% confidence intervals (CI).Among 109,862 women participating in the California Teachers Study cohort, 3844 were diagnosed with invasive ER+ breast cancer between 1997–1998 and December 2011. Based on validated self-reported height and weight at age 18, baseline, and 10-year follow up and waist circumference at 2-year and 10-year follow up, we identified 16 2) ≥25 vs <20 at age 18). Among postmenopausal women currently using hormone therapy, only those with the greatest body size had increased breast cancer risk . Among postmenopausal women not currently using hormone therapy, the relationship between body size and risk was complex, with the largest effects of adiposity among short women. Among short women, those with gluteal adiposity  and those who continued to gain weight throughout adulthood  were at greatest risk, whereas those who had been overweight/obese since adolescence were not at increased risk . Height was associated with a small increased risk, with borderline statistical significance.Premenopausal breast cancer was influenced by adolescent, but not adult, body size (HR = 0.51, 95% CI 0.31–0.86 for body mass index (BMI; kg/mConsidering absolute body mass in adolescence and at two points in adulthood, dynamic changes in adiposity over time, and body fat distribution, we identified obesity phenotypes associated with ER+ breast cancer risk. Our approach more clearly identifies specific risk groups than do analyses that evaluate similar measures separately. These findings may aid in improving risk prediction models and developing targeted interventions, and may clarify inconsistent findings across studies. One of the most serious public health crises of the last 30 years worldwide has been the rapidly increasing prevalence of overweight and obese individuals and the impact of this epidemic on the risk of many cancers and other chronic diseases. It is well-established that body size impacts breast cancer risk and that these associations vary by menopausal status and the use of hormone therapy (HT) –3. The rMost epidemiologic studies have examined body size measures as single independent variables or as the joint effects of two variables. However, the interrelationships between various body measurements are complex - individual measures are often correlated with each other  and over time within an individual. In addition, the associations between body size and disease risk reflect confounding and interactions and can vary over the life-course. For example, obesity early in life may not only reduce the risk of premenopausal breast cancer, but continued obesity throughout life may delay or ameliorate the risk of postmenopausal breast cancer normally associated with obesity in later life , 9, 10. The California Teachers Study (CTS) recruited 133,479 active and retired female public school teachers, administrators, and other professionals in 1995–1996 . At the 2), weight change, and waist-to-height ratio (WHtR). Self-reported height (in inches) at baseline and at age 18 years were highly correlated (r = 0.97). Thus, adult height was defined as height at baseline and if missing, as height at age 18. BMI was calculated based on self-reported weight (reported in pounds and converted to kilograms) at age 18 and baseline and adult height as described above (converted to meters). At the 2-year follow up, women were provided a standard heavy-weight flexible paper tape measure  and asked participants to measure their waist and hip circumferences following written, illustrated instructions. We chose to use WHtR, instead of waist-to-hip ratio, as a measure of abdominal adiposity as the former has been found to be a better predictor of visceral fat, while the latter is more strongly correlated with subcutaneous fat [Body size measures included in the present analysis were height, body mass index  under the assumption that among overweight/obese women the BMI attained was more important than the amount of weight gain. Similarly, body fat distribution (WHtR) was evaluated only among overweight/obese women under the assumption that in the absence of significant adipose tissue among women of normal weight, the site of that tissue had minimal effect. These assumptions also kept the total number of phenotypes evaluated at a reasonable number and were further justified by the very small number of women in most of the subgroups when additional stratification as described was examined post hoc. In a second set of analyses we also incorporated BMI at the 10-year follow up and weight change from baseline to the 10-year follow up, the latter among women of normal weight at the 10-year follow up.We used the following measures to identify lifetime body size phenotypes: adult height; adolescent BMI (at age 18 years); BMI at baseline; weight change from age 18 to baseline among women of normal weight  at baseline; and WHtR among women who were overweight  or obese (BMI ≥30) at baseline. Based on The CTS cohort is followed annually for cancer diagnoses, changes of address, and deaths. Cancer diagnoses are determined by linkage with the California Cancer Registry (CCR), a population-based cancer registry, which contributes data to the National Cancer Institute Surveillance, Epidemiology, and End Results program, and covers the entire state of California. As more than 99% of all cancer diagnoses among California residents are reported to the CCR , cohort in-situ breast cancer during that time period . Also excluded were 530 women with breast cancer whose ER status was unknown and 2586 women with unknown menopausal status or HT data at all three assessments . Thus, the analysis cohort included 109,862 women among whom 3844 were diagnosed with incident invasive ER+ breast cancer between completing the 2-year follow up in 1997–1998 and 31 December 2011.For the present analysis, we sequentially excluded women, who at baseline were judged to have invalid data overall (n = 2); did not live in California (n = 8867); had a prior history of breast cancer  or whose prior history of cancer was unknown (n = 139); had a bilateral mastectomy prior to joining the cohort (n = 11); or were aged 85 years or older (n = 1980). We began follow up for the present analysis at the time that the 2-year follow-up questionnaire was completed . Thus, we also excluded women who had moved out of California (n = 1711), died (n = 674), or had been diagnosed with an invasive or in-situ breast cancer , a move outside of California lasting more than 4 months (n = 9903), death , a bilateral mastectomy (n = 15), or the end of follow up (31 December 2011).Multivariable Cox proportional hazards regression was used to estimate hazard rate ratios (HR) and 95% confidence intervals (CI) relating breast cancer to measures of body size over time as a function of menopausal status and current HT use. Follow-up time was calculated as the number of days between completion of the 2-year follow-up questionnaire  and the first of the following six events: diagnosis of invasive ER+ breast cancer (n = 3844), diagnosis of ER-negative (ER-) or Menopausal status and HT use were collected at baseline and updated based on data collected at the 5-year and 10-year follow up. For each woman, these characteristics were modeled as time-varying covariates with four levels: premenopausal; postmenopausal, currently using HT; postmenopausal, not using HT; and unknown. Perimenopausal women (those with a last menses within the past six months) were included with the postmenopausal groups based on HT use. The data were represented as a counting process, with transitions at the dates of the two follow-up questionnaires (or the median completion date for non-responders) for each subject whose status changed. Three subsets of the resulting counting process data were created for subsequent analyses  and separate regression analyses were performed on each subset. There were 46,847 women who contributed time to the premenopausal subset, 49,581 to the postmenopausal/current HT use subset, and 60,278 women to the postmenopausal/no HT subset.Age (in days) was used as the time metric in all regression models, with stratification by age (in years) at baseline to adjust for calendar effects. Potential confounders were identified based on prior knowledge and their independent associations with breast cancer risk within each menopausal/HT subset in our cohort. All potential confounders were evaluated in each subset separately. For premenopausal breast cancer, covariates included in the final analyses were a history of benign breast disease  and family history of breast cancer in a first-degree relative . For postmenopausal breast cancer among women currently using HT, the covariates were nulliparity and among parous women, age at first full-term pregnancy (in years); history of benign breast disease; family history of breast cancer in a first-degree relative; average alcohol consumption in the year prior to baseline ; and neighborhood socioeconomic status (in deciles). For postmenopausal breast cancer among women not using HT covariates were age at menarche (in years from ≤9 to ≥17); nulliparity and among parous women, age at first full-term pregnancy; history of benign breast disease; family history of breast cancer in a first-degree relative; and consumption of a plant-based diet (factor score ). NeitheFor each menopausal/HT subset, our approach for identifying the lifetime body size phenotypes of importance proceeded in three steps. First, we examined the effects of each body size variable separately across a range of levels, collapsing each variable, when possible, into two or three categories based on the observed HRs and CIs, with the goal of maintaining prediction while achieving the most parsimonious model. Second, we used the categories identified from step one to create and evaluate a full model obtained by partitioning the dataset into a set of disjoint phenotype categories based on the joint consideration of height, adolescent BMI, BMI at baseline, weight change among those with normal BMI at baseline, and type of adiposity  among those who were overweight or obese, as described above. Finally, we repeatedly collapsed categories created in step two to achieve a final parsimonious model that maximized prediction. Collapsing of categories was based on sample size (precision) within each phenotype and comparisons of between-phenotype differences using the Wald test.Women with missing data on the covariates included in a given subset were omitted from the analyses reported in Tables At the start of follow up, 46,822 women were premenopausal, 36,977 were postmenopausal and currently using HT, and 21,788 were postmenopausal and not using HT (Table p trend = 0.006). Adult height was positively associated with risk of postmenopausal breast cancer . Breast cancer among postmenopausal women not using HT was also significantly associated with BMI at baseline and at the 10-year follow up and weight change in both early (age 18 years to baseline) and later (baseline to 10-year follow up) adulthood. The association between risk of breast cancer and abdominal (WHtR ≥0.50), as opposed to gluteal (WHtR <0.50), adiposity approached statistical significance.The most parsimonious version of each of the variables of interest which, when considered separately, predicted ER+ breast cancer risk in each of the menopausal/HT groups is shown in Table For each menopausal/HT group, we evaluated the association between ER+ breast cancer risk and the full spectrum of body size phenotypes (n = 16), defined by height, adolescent BMI, baseline BMI, weight change between age 18 years and age on joining the cohort, and abdominal adiposity Table . Among pp = 0.32). Among postmenopausal women not using HT, weight gain since adolescence, among women maintaining a normal BMI, increased risk among both short  and tall  women. Short women with gluteal adiposity at baseline  were at greater risk than those with abdominal adiposity  (p = 0.003); the location of body fat among tall women did not impact risk, although being overweight/obese did . Among short women who were overweight/obese in adolescence, those with normal BMI at baseline were at increased risk , whereas those who continued to be overweight/obese with greater abdominal girth were not  (p = 0.03).Among postmenopausal HT users, taller women who had become overweight or obese during adulthood were at increased risk of breast cancer. The difference in the magnitude of risk for those women with abdominal  vs gluteal  fat distribution was not statistically significant (p = 0.003).To obtain the most parsimonious predictive models, rare phenotypic combinations  were collapsed into single groups, as were groups with similar risk estimates, using an iterative process. In premenopausal women, only adolescent (age 18 years) BMI remained predictive of risk  modified any of the risk estimates in Table Our analysis suggests that the relationships between body size phenotypes, based on measures from adolescence through adulthood, and ER+ breast cancer are complex. We observed that the risk of premenopausal breast cancer was influenced by adolescent, but not adult, body size, with greater body mass associated with a reduction in risk. In addition, while becoming overweight/obese in adulthood impacted the risk of postmenopausal breast cancer, having been overweight/obese over life since adolescence did not. The use of HT substantially increases breast cancer risk , 17; thiAmong postmenopausal women not using HT, the relationship between body size and risk was complex, with the largest effects of adiposity observed among short women. Among short women, while weight gain during adulthood resulting in abdominal adiposity increased risk, gluteal adiposity was significantly more detrimental; however, among tall women, body fat distribution did not modify the risk associated with being overweight or obese in adulthood. Among short women, continued weight gain throughout adulthood was also associated with a significant increase in risk. Height was associated with increased risk, with borderline statistical significance.Our findings on the associations between single body-size measures and breast cancer risk Table  were conApart from single measures assessed at different ages and reported separately, there is little literature on the lifetime effects of body size on breast cancer risk. Studies in France and Mexico have looked at body shape trajectories from the prepubertal period to age 35 or 40 years based on Sørensen’s pictograms , 20. In In a similar analysis, conducted in the USA, assessing trajectories from age 5 to 60 years, moderate or marked increases in body size increased the risk of postmenopausal breast cancer, but there was no increased risk among those whose body size was relatively stable throughout life, regardless of their absolute body size . While tUnlike adult-acquired body mass, several previous studies have found that being overweight/obese over lifetime  may not impact the risk of postmenopausal breast cancer , 10, 20 Mechanisms related to sex steroid hormones, inflammation, and glucose/insulin are suggested as the pathways most likely to be involved in anthropometric-related carcinogenesis , 2, 7. AWeight gain is an indicator of sustained positive energy balance and, along with adult obesity, affects circulating hormones, growth factors, insulin, and inflammatory cytokines which together can increase carcinogenesis, decrease apoptosis, and stimulate low-grade chronic inflammatory responses , 7, 19. a priori, our approach to and interpretation of the analysis is somewhat agnostic, has a certain degree of subjectivity, involves multiple comparisons, and for some subgroups is based on small numbers of cases. However, we used quantitative methods, i.e., the Wald test, to determine whether specific subgroups differed. While collapsing subgroups based on small numbers of cases may have masked some associations, this may also have reduced over-interpretation of erroneous patterns.Several limitations of the present analysis should be noted. First, while determined Second, we included only 16 body-size phenotypes in our analysis. Examining additional phenotypes, such as absolute weight gain among women with who were overweight or obese in adulthood, being overweight or obese over life, or body fat distribution among women of normal BMI, may be possible in larger consortial datasets.Third, our focus was on body size over the life-course but the available data limited us to evaluation at several specific points in time only, i.e., age 18 years, baseline , and 10 years after baseline, and the changes between these points.Fourth, while data on menopausal status and HT use were updated, this was only done at 5-year and 10-year follow up, rather than more often, and thus, has some built-in imprecision. The largest change in HT use over the follow-up period, however, was the substantial population cessation of HT use following the publicity surrounding the findings of the Women’s Health Initiative in 2002–2003 , 17. ThiFifth, the anthropometric data used in the present analysis were self-reported, which can result in measurement error due to lack of knowledge, most notably for weight at age 18 years, or desire to report a socially more normative value. However, our validation study suggested excellent reproducibility and validity, minimizing such concerns . Last, wNotable strengths of this analysis include the unique conceptual approach taken to assessing the effects of body size over the life-course and the conduct of these analyses in a large cohort of women who had detailed data on anthropometry and breast cancer outcomes over the course of more than 15 years. We included both dynamic  and static measures  of body size, of which the former may better reflect age-related metabolic changes, while the latter reflects the effects of absolute size . In addiTaking into account absolute body mass, changes in adiposity over time, and body fat distribution, we identified lifetime (since adolescence) obesity phenotypes which were associated with breast cancer risk in our large cohort. These findings may aid in improving risk prediction models and developing targeted interventions, and may clarify inconsistent findings across studies to the extent that the composition of the study populations differ in regards to important anthropometric indicators. To the extent that equally detailed anthropometry is available in other studies, similar analyses conducted in large consortial datasets, such as the Cohort Consortium or the Harvard Diet Pooling Project, are needed to confirm our findings and improve statistical power for evaluating effect modification across rare phenotypes.


Mammographic density decreases and involution of breast tissue increases with age; both are thought to be risk factors for breast cancer. The current study investigated the relationship between involution or hormone treatment (HT) and breast density among multiethnic patients with breast cancer in Hawaii.Patients with breast cancer cases were recruited from a nested case-control study within the Multiethnic Cohort. HT use was self-reported at cohort entry and at the time of the density study. Mammographic density and involution in adjacent non-tumor breast tissue were assessed using established methods. Linear regression was applied to evaluate the correlation between involution and four density measures and to compute adjusted means by involution status while adjusting for confounders.p = 0.15). In contrast, the size of the dense area was significantly associated with involution (p = 0.001); the values ranged from 29.7 cm2 for no involution to 48.0 cm2 for complete involution. The size of the total breast area but not of the non-dense areas was also larger with progressive involution. Percent density and dense area were significantly higher in women with combined HT use.In the 173 patients with breast cancer, mean percent breast density was 41.2% in mammograms taken approximately 1 year before diagnosis. The respective proportions of women with no, partial, and complete involution were 18.5, 51.4, and 30.1%, respectively and the adjusted density values for these categories were 32.5, 39.2, and 40.2% (Contrary to previous reports, greater lobular involution was not related to lower mammographic density but to higher dense area. Possibly, percent density during the involution process depends on the timing of mammographic density assessment, as epithelial tissue is first replaced with radiographically dense stromal tissue and only later with fat. The human breast has 15–20 lobes, each with many lobules containing acini, the secretory structures of the breast . DelayedInvolution of the glandular structures of the breast may be reflected in mammographic density, an independent predictor of breast cancer. Women with extensive breast density >75%) have fourfold to six-fold higher risk than women with low (<5%) density , 7. Tiss5% have fIn women attending the Mayo clinic with benign breast disease, the mean percent density values by none, partial, and complete involution status were 22, 22, and 17%, respectively, after adjustment for known risk factors , the comThe current pathologic investigation  is basedThe MEC is linked annually to the statewide Hawaii Tumor Registry (HTR) to identify incident cancer cases. Invitations for the pathology study were mailed to 430 of the 607 women in the NCC study, for whom tumor blocks were available through the HTR. Of the 279 women with breast tumor tissue represented on microarrays , blocks Mammographic images of study participants from clinics throughout the State of Hawaii were retrieved and digitized using a Kodak LS 85 Film Digitizer  with a pixel size of 260 μm . For thePathologic blocks were retrieved through the tissue repository of the HTR. H&E slides (mean = 2.6 per woman) of normal (non-tumor) tissue adjacent to but not immediately bordering the tumor were prepared. The extent of breast tissue lobular involution Fig.  in breas2), ethnicity , parity , menopausal status, and HT use .The statistical analysis was performed using the SAS statistical software . We computed frequencies and means for variables of interest by involution status. Multiple linear regression was applied to evaluate the relationship between involution and mammographic measures  and to compute adjusted means by the category of involution and HT. Separate models for premenopausal and postmenopausal women were analyzed. Trend tests were performed using the indicator variables for involution status as a continuous variable. All models were adjusted for covariates known to be associated with breast density: age at mammogram, body mass index (BMI)  and advanced (12.1%). Involution status differed significantly by age at diagnosis (p = 0.01) with low involution among women under 50 years of age and higher proportions in women 60 years and older (Table p = 0.58).The mean age at breast cancer diagnosis in the 173 women in the involution study  was 59.7 ± 8.0 years as compared to 61.4 ± 8.7 years in the 279 participants in the original study (Table p = 0.96). The difference across categories increased after adjustment for confounders  but was not significant (p = 0.15). In contrast, the size of the dense area differed significantly in the unadjusted (p = 0.03) and adjusted models (p = 0.001) with the highest value for women with complete involution (48.0 cm2) and the lowest (29.7 cm2) for those with no involution. The non-dense area varied little , whereas the total breast area was significantly higher with more advanced involution before (p = 0.009) and after adjustment . Interaction terms and stratified analyses did not indicate any differences by menopausal status. Involution was not associated with percent density in premenopausal or postmenopausal women , whereas the dense area remained higher with progressive involution .The mean breast density in all women was 41.2%; the unadjusted values  and dense area  were higher in women with combined HT use, but the non-dense and the total area was not associated with HT use.HT was significantly associated with several mammographic measures Fig. . PercentAs in previous reports, age was a strong predictor of involution among MEC participants in Hawaii; complete involution is uncommon before the age of 50 years and increases to as much as 50% in women aged 60 years and older , 9. In tOur finding of larger dense areas on mammograms of more involuted breasts suggests that women with a larger degree of involution may not have more fatty tissue but rather a higher proportion of stromal tissue. Thus, the mammographic images appear radiographically dense despite being poor in epithelial cells. In the two previous reports , 12 of iOur findings confirm the strong association between mammographic density and HT, especially estrogen and progesterone combined , but theStrengths of the current study include the ethnic diversity with a wide range of mammographic density values , the avaContrary to previous reports , 12, gre


The racial difference remained after adjustment for clinical factors and family history . The association between contralateral prophylactic mastectomy and a reduction in the perceived risk of second breast cancers was significantly smaller for blacks than whites. Blacks were less likely than whites to undergo contralateral prophylactic mastectomy even after adjustment for clinical factors. This racial difference in use may relate to the smaller impact of contralateral prophylactic mastectomy on the perceived risk of second breast cancers among blacks than among whites. Future research is needed to understand the overall impact of perceived risk on decisions about contralateral prophylactic mastectomy and how that may explain racial differences in use.Contralateral prophylactic mastectomy use has increased over the past decades among women with early-stage breast cancer. Racial differences in contralateral prophylactic mastectomy use are well described, but with unclear causes. This study examined contralateral prophylactic mastectomy use among black and white women and the contribution of differences in perceived risk to differences in use. We surveyed women diagnosed with early-stage unilateral breast cancer between ages 41–64 in Pennsylvania and Florida between 2007–2009 to collect data on breast cancer treatment, family history, education, income, insurance, and perceived risk. Clinical factors—age,stage at diagnosis, receptor status—were obtained from cancer registries. The relationships between patient factors and contralateral prophylactic mastectomy were assessed using logistic regression. The interaction between race and contralateral prophylactic mastectomy on the perceived risk of second breast cancers was tested using linear regression. Of 2182 study participants, 18% of whites underwent contralateral prophylactic mastectomy compared with 10% of blacks ( Racial disparities exist in the desire of American women with early-stage breast cancer to surgically remove their healthy breast tissue. Younji Kim and colleagues from the Massachusetts General Hospital in Boston, USA, surveyed more than 2100 middle-aged women from Pennsylvania and Florida who were newly diagnosed with early-stage cancer in one breast. They asked about the women’s medical and family histories, perceived risk of further disease, and assorted demographic variables. After adjusting for clinical factors and family history, white women were more than twice as likely to undergo contralateral prophylactic mastectomy, in which both breasts are surgically removed, than were black women. The authors surmise that the racial discrepancy may result from perceptual differences among populations about the benefits of bilateral mastectomies on future cancer risk, although more research is needed into the decision-making process. One factor that may contribute to racial differences in CPM use is differences in perceived breast cancer risk between black and white women. Several studies have found that black women tend to have a lower perceived risk of breast cancer than white women.20 Furthermore, one study also found that black women had a lower perception of the benefit of screening mammography on breast cancer mortality than white women,21 raising the possibility of differences in the perceived effectiveness of other preventive interventions such as CPM. However, to our knowledge, there are no published studies investigating the potential contribution of differences in risk perception to racial differences in use of CPM.Uptake of CPM has been demonstrated to be substantially higher among white than black women,Given this background, this current study examined CPM use among a large, population-based sample of black and white women diagnosed with early-stage breast cancer. In addition to testing the contribution of clinical and socioeconomic characteristics to racial differences in CPM use, we investigated whether the association between CPM use and perceived risk of a second breast cancer differed between black and white women and may have contributed to differences in cancer treatment use.p = 0.001). Black women were less likely to have any family history of breast or ovarian cancer compared to white women , but a greater proportion of black women had three or more first or second-degree relatives with breast or ovarian cancer compared to white women . Black women were more likely to have negative estrogen receptor (ER)/ progesterone receptor (PR) status, income lower than $30,000 per year, government supported insurance—Medicaid or Medicare—and lower educational attainment than white women. There were also small but statistically significant differences in BRCA1/2 mutation risk between black and white women, with more white women being at high risk, whereas more black women being at low risk (p = 0.04).Of the 2182 study participants, 1333 (61%) were white and 849 (39%) were black (Table p < 0.001). When adjusted for age and stage at diagnosis, ER/PR status, and family history of breast or ovarian cancer, white women had more than twice the odds of undergoing CPM compared to black women (Table p < 0.001). In addition, women who were diagnosed with breast cancer at younger ages or at stage II (vs. stage I) or had more family members with breast or ovarian cancer were more likely to undergo CPM , whereas among women who had not undergone CPM, 16% of whites and 41% of black women reported 0% perceived risks of a second breast cancer (p < 0.001). However, in an adjusted model, the difference in perceived risk of a second breast cancer between women who had and had not undergone CPM was smaller among black women than among white women (Table p = 0.03 for interaction). Similarly, in stratified linear regression, use of CPM was associated with a five point difference in risk perception among black women  but a 15 point difference among white women .As expected, women who had undergone CPM had a substantially lower perceived risk of a second cancer than women who had not undergone CPM Table . Among w6 with higher rates among white women than black women.17 Prior studies have been unable to explain the difference in CPM use by racial differences in clinical or sociodemographic factors. Our findings support this racial difference in utilization and suggest one possible explanation for the difference.The use of CPM among women with early-stage breast cancer has increased substantially in the U.S. over the last decade,26 In addition, several studies have found that the degree of cancer worry of recurrence and perceived risk for contralateral breast cancer can influence decisions about cancer treatments.30 A previous study of breast cancer patients diagnosed at age 40 or younger found that those who had undergone CPM had lower degree of worry about recurrence following surgery than women who had not undergone CPM,23 which is similar to the pattern of perceived risk observed among white women in our study. In this retrospective study by Rosenberg et al.,23 however, 86% of the study population was non-Hispanic white and racial differences in patients’ worry about cancer recurrence were not assessed. Parker et al.27 surveyed newly diagnosed early-stage breast cancer patients prior to surgery, and found that women with greater cancer worry were more likely to undergo CPM, though the study did not evaluate differences by race due to a relatively small sample size (<200) and few non-white participants. Among women diagnosed with breast cancer, one study found that black women were more likely than white women to think that the chances of breast cancer recurrence are the same for mastectomy as for other less aggressive treatments.31 A second study found that black breast cancer patients reported less worry about cancer returning to the same breast, to the other breast, or spreading to other parts of the body compared with white breast cancer patients.32 In addition, a population-based survey of breast cancer patients that included nearly 450 black women found that patients who reported that concerns about breast cancer recurrence were very important in their surgical decision making were more likely to have had mastectomy.33 Furthermore, as noted previously, black women without breast cancer have been demonstrated to have a lower perceived risk of developing breast cancer than white women,20 even among women with higher than average risk due to family history18 or other risk factors.19 While these findings suggest a mechanism linking differences in perceived risk to racial differences in CPM, we were not able to measure risk perception prior to CPM use and additional prospective longitudinal studies of risk perception pre and post CPM are needed.Among the over 2000 women with early stage breast cancer in this current study, black women who did not undergo CPM had a lower perceived risk of a second breast cancer and the apparent impact of CPM on the perceived risk of a second breast cancer was smaller among black than white women, suggesting that black women may have a lower perceived risk of a second breast cancer than white women and that they may see CPM as less effective at lowering that risk. First, the racial differences in perceived risk are supported by findings from other retrospective studies which suggest that, in general, white women are more likely to overestimate risk of developing breast cancer, and perceived risk is lower among black women.BRCA1/2 mutations,34 there is no optimal rate of uptake and racial differences may represent overuse among white women as much as underuse among black women. Risk of a contralateral breast cancer is associated with genetic susceptibility, such as germline BRCA1/2 mutation, or a strong family history of breast cancer and the decision to undergo CPM was associated with family history and cancer stage in our study, suggesting that uptake is partly related to risk factors. However, given that black women are actually at an elevated risk of contralateral and second breast cancers compared to white women,35 the lower rates of CPM use among black women are surprising if the decision is driven by the risk of recurrence. Although racial differences in preference sensitive decisions can be more complex to unravel, they are an increasingly important source of differences in outcomes in the era of precision medicine. Ensuring that these decisions are informed choices without constraints created by inadequate access or information will be critical for the benefits of precision medicine to reach all populations.Given that CPM is not currently recommended by current advisory groups for women not known to have 37 Such differences may mean that black women are less likely to receive adequate information about their cancer management options including the risk of a second cancer and the potential impact of CPM on that risk, which may in turn lead to racial differences in treatment use.39 Furthermore, it is not clear from these results whether white women are more likely to have an exaggerated perception of their second breast cancer risk and overuse CPM or whether black women underestimate their risk and underuse CPM.The reasons for these racial differences in risk perception are not clear but this study indicated that the lower risk perception is unlikely to be driven by actual differences in risk. At the same time, minority patients have been found to experience different, and often inferior, communication with their physician and decision-making processes in several areas including cancer treatment.This study has several strengths. To our knowledge, it is one of few studies to examine the likelihood of undergoing CPM by race and by patients’ risk perception of second breast cancers in a large, population-based sample of racially diverse breast cancer patients. Also by including both patient survey and cancer registry data, it included a wide range of potential explanations for the disparity in treatment use including age and stage at diagnosis and family history information, which is a critical factor, as well as patients’ attitudes and perceptions of cancer treatments. However, this study has a few limitations. Our patient survey had insufficient evidence to determine whether the racial disparities in CPM use are driven by overuse of the procedure by white women or underuse by black women. Also, we did not adjust for income or insurance status, which might partially underlie racial differences. Additionally, since the patient survey was conducted following breast cancer treatment, we do not know whether risk perception was similar or changed before and after CPM. Risk perception measured prior to the procedure could have enhanced the analysis and allowed assessment of whether differences in risk perception before CPM explained racial differences in CPM use.Racial disparities in CPM among white and black women are large and may be related to differences in perceived risk of a second cancer and the impact of CPM on that risk. Future studies are needed to determine the underlying causes of differences in perceived risk between black and white women, how perceived risk changes before and after a surgical procedure, and how it impacts their decision-making process for cancer treatments.40 The survey consisted of a total of 63 questions asking study participants about characteristics of breast cancer, any surgical treatment done for their breast cancer, perceived risk of a second breast cancer, other personal health history and family histories of ovarian or breast cancer. For treatment, women were instructed to report only treatments given for the breast cancer at the time it was first diagnosed, and not include treatments for any cancer that came back after the original treatment. Perceived risk of developing a second breast cancer was measured using the following survey item: “What do you think your chance is of developing a second breast cancer in your lifetime? Please choose a number between 0% (no chance of breast cancer) and 100% (definitely will get breast cancer).” The study was approved by the University of Pennsylvania and Partners Healthcare Institutional Review Boards.This study included women who were diagnosed with early-stage unilateral breast cancer at ages 41–64 between January 1, 2007 and December 31, 2009 identified through Pennsylvania and Florida cancer registries. These states were included because of the size and diversity of their populations and the ability to directly contact patients from cancer registry files. Based upon the cancer registry data, the majority of the study participants were residents living in Pennsylvania and Florida with a small portion from neighboring states. We included all black women and an equal random sample of white womento facilitate comparisons by race. Women were sampled based upon race recorded in the cancer registry. Thirty women were excluded because they reported a different race when surveyed. Women were surveyed by mail 2–3 years after cancer diagnosis with additional telephone recruitment of black non-responders up to 4 years from diagnosis. Details of the survey methods have been published.41 Breast cancer treatment use was measured with survey questions asking whether a study participant received following treatments: lumpectomy, mastectomy, bilateral mastectomy, and adjuvant treatments such as radiation therapy, chemotherapy or hormonal therapy. Family history—both first and second degree—of breast or ovarian cancer, education, income, and insurance status were also ascertained through the survey. Age and stage at diagnosis, and ER/PR status were obtained from cancer registry data. At the end of the recruitment, we excluded seven women, who were diagnosed with bilateral breast cancer, based on cancer registry data.The overall response rate was 61% with the response rate being slightly higher among white women (62%) in comparison to black women (58%) when calculated using the Response Rate Definition #4 defined by the American Association for Public Opinion Research.BRCA1/2 mutation risk 40 were compared for black and white participants using Chi-Square tests. The effect of patient factors and race on CPM was assessed with logistic regression models adjusted for the factors described above. Perceived risk of a second breast cancer and risk perception stratified by use of CPM were compared between black and white participants using Chi-square tests. Linear regression was used to test the interaction of CPM and race on perceived risk of a second breast cancer, adjusting for age, stage at diagnosis, ER/PR status, and family history of breast and ovarian cancer, and linear regression of the association between CPM and risk perception was stratified by race. All statistical tests were two-sided with a significance level of p < 0.05. Statistical software STATA/IC version 14 was used for all analyses .Patient characteristics, including age at diagnosis (5-year categories), stage at diagnosis (AJCC Stages I or II) and ER/PR status , family history of breast or ovarian cancer in both first and second degree relatives , and Study subjects did not provide informed consent for public sharing of the study data.


N-acetylation and carcinogen activation through local O-acetylation. NAT2 slow acetylation status is significantly associated with increased bladder cancer risk among European populations, but its association in Asian populations is inconclusive.N-acetyltransferase 2 (NAT2) is involved in both carcinogen detoxification through hepatic NAT2 acetylation status was determined by both single nucleotide polymorphisms (SNPs) and caffeine metabolic ratio (CMR), in a population-based study of 494 bladder cancer patients and 507 control subjects in Shanghai, China.N-acetylation, was significantly reduced in a dose-dependent manner among both cases and controls possessing the SNP-inferred NAT2 slow acetylation status . The CMR-determined slow N-acetylation status (CMR<0.34) was significantly associated with a 50% increased risk of bladder cancer  whereas the SNP-inferred slow acetylation statuses were significantly associated with an approximately 50% decreased risk of bladder cancer. The genotype-disease association was strengthened after the adjustment for CMR and was primarily observed among never smokers.The CMR, a functional measure of hepatic N- and O-acetylation in bladder carcinogenesis, particularly in populations exposed to different types of bladder carcinogens.The apparent differential associations for phenotypic and genetic measures of acetylation statuses with bladder cancer risk may reflect dual functions of NAT2 in bladder carcinogenesis because the former only measures the capacity of carcinogen detoxification pathway while the latter represents both carcinogen activation and detoxification pathways. Future studies are warranted to ascertain the specific role of  Urinary bladder cancer is the fourth most common cancer in men of the United States . Known rN-acetyltransferase 2 (NAT2). The enzyme detoxifies carcinogens such as arylamines in the liver by transferring an acetyl group to an exocyclic amine (N-acetylation). Alternatively, NAT2 may activate carcinogens by transferring an acetyl group to the oxygen group of N-hydroxy-aromatic or heterocyclic amines (O-acetylation) [N-acetylation capacity can be determined phenotypically by quantifying the urinary caffeine metabolite ratio (CMR) [NAT2 gene [N-acetylation status in the liver and O-acetylation activity in the urinary tract. Currently, there is no method available for direct measure of local O-acetylation activity in vivo.Many environmental and occupational carcinogens undergo catalysis by ylation)   . More reio (CMR)  or a tagAT2 gene . The genN-acetylation activities [NAT2 gene and different levels of exposure to tobacco and other environmental bladder carcinogens.Epidemiological studies in Europe and United States, especially those among smokers, have reported associations between SNP-inferred NAT2 slow acetylation status and increased risk of bladder cancer. It is consistent with the hypothesis that NAT2 plays an important role in detoxifying arylamines present in tobacco smoke through hepatic tivities –12. Howetivities , SNP-inftivities , 15. It tivities . Furthertivities , 18. On tivities , 19–21. NAT2 SNP panel and the novel tag SNP of NAT2 gene in a Chinese population, (2) the causal relationship between the SNP-inferred acetylation status and CMR, a functional measure of hepatic N-acetylation, and (3) the association between SNP- and CMR-determined NAT2 acetylation status separately or in combination and the risk of bladder cancer in a relatively large population-based case-control study in Shanghai, China.There are few reports that examined the association between NAT2 acetylation status and bladder cancer risk among Asian populations. Their results were inconclusive , 22–27. Participant characteristics are shown in Table NAT2 gene. Among control subjects, minor allele frequencies (MAF) ranged from 0.03 to 0.45 (Table r2 ≥0.94), whereas a moderate correlation was observed between 282 C>T (rs1041983) and 590 G>A (rs1799930) (r2=0.44). No correlation was observed between other pairs of the candidate SNPs among controls. The tag SNP rs1495741 was only correlated with 282 C>T (rs1041983) (r2=0.77) (After excluding a monomorphic SNP rs1801279) in the study population, we analyzed 6 candidate SNPs and a tag SNP of the 79 in ther2=0.77) . Allele r2=0.77) .NAT2 genotypes partially reflected hepatic N-acetylation function measured by CMR. Among control subjects, minor alleles of all individual SNPs were associated with lower level of CMR compared to major alleles (Table P-trends ≤ 0.05). Similar genotype-phenotype associations were found in bladder cancer patients except for the three SNPs with extremely low MAF. NAT2 acetylation status inferred genotypically by the tag SNP and the 6-SNP panel were highly correlated in both controls (2r=0.87) and cases (2r=0.96) (P < 1.4×10−30)  (Table 4×10−30) , indicat0) Table .NAT2 genotype . Among subjects with the SNP-inferred NAT2 rapid acetylation status, however, cases had a 4% higher in CMR than controls, but the difference was not statistically significant (P = 0.28).Patients with bladder cancer overall had statistically significant 8.7% lower CMR than controls (P = 0.03) Table . CompareP-trend < 0.03) than by the 6-SNP panel approach (P-trend = 0.06). On the other hand, low level of CMR  was associated with an increased risk of bladder cancer compared to high level of CMR  significantly strengthened the association between SNP-inferred acetylation status and bladder cancer risk; the slow acetylation status was associated with approximately 50% reduced risk of bladder cancer compared with the rapid acetylation status (P-trends ≤ 0.003). Conversely, the adjustment for SNP-determined acetylation status also strengthened the CMR-bladder cancer risk association (Table NAT2 genotype and CMR in the same model (tolerance > 0.86). The association between the SNP-inferred acetylation status and bladder cancer risk was much stronger in never smokers than that in ever smokers. Furthermore, the association between SNP-inferred acetylation status and bladder cancer became even stronger in lifelong never smokers who were not exposed to environmental tobacco smoke (ETS), determined by non-detectable total cotinine in urine (data not shown).Overall SNP-inferred slow acetylation status was significantly associated with reduced risk of bladder cancer compared with rapid acetylation status Table . This riP-trends ≤ 6.0×10−5). The associations were not strengthened by further stratification by smoking status, possibly due to limited number of subjects in each category (data not shown). In contrast, among subjects with CMR < 0.34, the SNP-inferred slow acetylation status was associated with statistically non-significant increase in risk of bladder cancer. The difference in the genotype-disease relationship between the high and low CMR groups was statistically significant (P-interactions ≤ 0.01).We further examined the associations between the SNP-inferred acetylation status and bladder cancer risk stratified by CMR levels Table . Among sNAT2 gene in Chinese people; 2) Both the single tag SNP and multiple candidate SNPs reflect variation in CMR, a measure of hepatic N-acetylation capacity; 3) The SNP-inferred slow acetylation status is significantly associated with a reduced risk of bladder cancer whereas the CMR-determined slow acetylation status is significantly associated with increased risk of bladder cancer as reported previously in this study population [O-acetylation rather than N-acetylation plays an important role in the observed SNP-bladder cancer risk association. Conversely, the effect of CMR-determined slow acetylation status on bladder cancer risk was greatly increased after controlling for genetic variation in the NAT2, further suggesting hepatic N-acetylation measured by CMR is a detoxification pathway of bladder carcinogen arylamines. 4) The SNP-inferred slow acetylation and reduced risk of bladder cancer was mainly confined to never smokers, further suggesting the potential role of NAT2 in the activation of non-tobacco bladder carcinogens. These novel and intriguing findings demonstrate a more complex function of the NAT2 gene in bladder carcinogenesis than previously appreciated.The present study with a relatively large sample size in an Asian population demonstrates several novel findings. 1) The acetylation status inferred by a single tag SNP captures almost all genetic variations in the exon 2 region of the pulation  as well pulation . The assN-acetylation activity of NAT2 whereas NAT2 genotypes potentially reflect both N- and O-acetylation activities [N-acetylation) and activation (O-acetylation) have been long described in the liver [N-acetyltransferase activities have been reported in human bladder [N-acetyltransferase activity (selective for NAT1) and N-hydroxy-ABP O-acetyltransferase activities (not selective for NAT1 or NAT2) in human bladder cytosols do not correlate [O-acetylation function in the local urothelium.Urinary CMR primarily measures hepatic tivities , 28, 29.he liver , 31. It he liver –34. The  bladder , 36. Mororrelate . These fN-acetylation in the detoxification of bladder carcinogens [NAT2 variant alleles share one or more common missense SNPs that decrease gene expression, enzyme activity or enzyme stability that affect both N- or O-acetylation functions [NAT2 SNP-inferred slow acetylation status potentially measured variations in both N- and O-acetylation catalytic capacities [O-acetylation in the activation of bladder carcinogens, leading to elevated risk of bladder cancer for individuals who carried high functional alleles of the NAT2 gene. This was further supported by a stronger association between the SNP-inferred slow acetylation status and decreased bladder cancer risk among individuals with higher CMR.The increased risk of bladder cancer associated with low CMR observed in the present study as well as by others supported an important role of hepatic cinogens , 20, 37.unctions , 38. Thepacities , and wasN- and O-acetylation pathways [N-acetylation pathway. Epidemiological studies and genome-wide association (GWA) studies in Europe consistently reported higher risk of bladder cancer associated with the SNP-inferred NAT2 slow acetylation status among ever smokers [O-acetylation pathway.Different carcinogens are targeted by the pathways . Therefo smokers , 40, 41.O-acetylation of NAT2 but not detoxification through hepatic N-acetylation due to the steric hindrance of the exocyclic amine [O-acetylation of N-hydroxy-heterocyclic amines accounted for the association between NAT2 rapid acetylation status and increased risk of colorectal cancer among people who frequently consumed well-done meat [O-acetylation pathway in the urinary bladder [Metabolism of heterocyclic amines (HCAs) involves primarily activation through local ic amine . Althougone meat –45. A po bladder . Indeed, bladder . Future NAT2 gene was confirmed by CMR, a functional measure of hepatic N-acetylation. The simultaneous measurements of both CMR and the NAT2 SNPs (reflecting both N- and O-acetylation) allowed for the assessment of the putative association between the O-acetylation status and bladder cancer, which provides insight on the potential biological mechanism of NAT2 genetic variants on bladder carcinogenesis.Notable strengths of the study included population based design, relatively large sample size and homogenous study population (only Han Chinese). We collected detailed information on various aspects of participants' characteristics and controlled potential confounding effects such as smoking. Furthermore, urinary total cotinine was quantified and active and passive smoking status was confirmed. More importantly, the function of the SNPs in the N-acetylation function. There was a high proportion of patients with bladder cancer quit smoking after their cancer diagnosis  eligible patients between July 1996 and June 1999. The diagnosis of bladder cancer of 531 (91%) patients was based on histopathological evidence and diagnosis of the remaining 50 (9%) patients was based on positive computerized tomography scan and/or ultrasonography with consistent clinical history.The Shanghai Bladder Cancer Study has been described in detail elsewhere . BrieflyControl subjects were randomly selected from urban residents of Shanghai through the City Residents Registry. Controls were chosen to match the frequency distribution by sex and 5-year age groups of patients with bladder cancer. Among the 750 randomly selected control subjects, 74 were untraceable and 72 refused to participate in the study. The remaining 604 (80%) subjects were interviewed between July 1996 and June 1999. The study has been approved by institutional review boards at the Shanghai Cancer Institute, the University of Minnesota and the University of Pittsburgh. Consent forms have been signed by all study participants.In-depth in-person interviews using a structured questionnaire were conducted to collect information from each eligible subject on a variety of factors known or suspected to be related to bladder cancer. The questionnaire included background information, demographics, history of tobacco smoke, history of passive smoking (for non-smokers only), history of alcohol, coffee, tea, soft drinks and plain water drinking, use of hormone replacement therapy (for women only), medical history, usual adult diet and occupational history, from birth to up to 2 years before the diagnosis of bladder cancer for cases and 2 years before the date of interview for controls .All study participants were asked to donate blood and urine samples at the end of the interview. One 10-ml blood sample was collected from each study participant in a heparin coated tube and fractioned into plasma, buffy coat and erythrocytes on the day of the sample collection. All components of the blood samples were stored at −80°C. For the collection of overnight urine sample, each subject was given two packets of Nestle instant coffee or two cans of Coca-Cola classic drink (about 70 mg of caffeine) to be drunk between 3 pm and 6 pm. An overnight urine sample was collected by the subject, picked up by the interviewer in the following morning, processed, acidified (400 mg of ascorbic acid per 20 ml of urine) and stored at −80°C until analysis. A total of 535 (92%) of the 581 interviewed cases and 543 (90%) of the 604 interviewed control subjects donated blood and urine samples. After excluding subjects with missing information on any of the SNPs genotyped (3 cases and 2 controls) or urinary CMR (13 cases and 32 controls), 478 bladder cancer cases and 473 control subjects were included in the present study.N-acetylation function was determined phenotypically by ratio of urinary caffeine metabolites (CMR) using the following formula: AAMU/(AAMU+ MX+MU). The ratios enabled differentiation at a cut-off of 0.34 and study participants were classified as slow (ratio < 0.34) or rapid (ratio ≥ 0.34) acetylators [The measurement of urinary caffeine metabolites, i.e. 5-acetylamino-6-amino-3-methyluracil (AAMU), 1-methylxanthin (MX), 1-methyluric acid (MU) and 1,7-dimethylxanthin (17X) has been described in detail elsewhere . Brieflytylators .Urinary total cotinine was measured by the standard gas chromatographic-mass spectrometric method as described previously . For theGenomic DNA was extracted in batches from peripheral blood buffy coats using QIAmp DNA mini kit according to manufacturer's protocol . Quality and quantity of purified DNA were evaluated using Nanodrop UV-spectrometer . DNA samples were stored at −80°C until analysis and plated and genotyped at the Genomics Core Facility at University of Minnesota using MassARRAY technology and iPLEX Gold Assay . Five percent duplicates and two sets of in-house trio samples were included for quality control purposes. The concordance among blind duplicate pairs was >99.95%. The average successful genotyping rate for each sample and SNP was 100%.NAT2 gene was used to determine NAT2 haplotypes and infer acetylation status [NAT2 191G>A (rs1801279), was not polymorphic in our study population and hence was excluded from further analysis. The genotype frequencies for the other six SNPs were all in Hardy-Weinberg equilibrium among the control population. Individuals carrying two of the NAT2 alleles associated with rapid acetylation status, i.e. NAT2*4 (wild type), NAT2*12A (803 A>G) or NAT2*13A (282 C>T), were classified as rapid acetylators. Individuals carrying two of the NAT2 alleles associated with slow acetylation status, i.e. NAT2*5A (341T>C and 481 C>T), NAT2*5B , NAT2*5C (341T>C and 803 A>G), NAT2*6A (282 C>T and 590 G>A), NAT2*7B (282 C>T and 857 G>A) were classified as slow acetylators. Individuals carrying one rapid acetylation allele and one slow acetylation allele were classified as intermediate acetylators [A conventional panel of seven SNPs in exon 2 of the n status . The pan91G>A rs101279, waNAT2 gene was also genotyped [In addition to the 6-SNP panel, a tag SNP rs1495741) recently identified among European populations at the 3′ end of the enotyped . This SN41 recentt-test for continuous variables between cases and controls. Pearson's correlation coefficient, 2r and corresponding P values were calculated for measuring pairwise correlation between two SNPs. Linkage disequilibrium map for the tag SNP rs1495741 in relation to 6 candidate SNPs were generated using Haploview [Chi-square test was used to examine the difference in distributions of categorical or nominal variables and Student aploview . AnalysiP values to measure the strength of associations between the SNP-inferred or CMR-determined acetylation status and bladder cancer risk with adjustment for age, sex, smoking status, number of cigarettes per day, and number of years of smoking [O-acetylation on bladder cancer risk. We assumed additive genetic effects and homozygous wild-type, heterozygous, and homozygous variant genotypes were coded as 0, 1, and 2, respectively, in the trend test. To test collinearility between NAT2 genotype and CMR, the tolerance of each variable in the model was requested, with a value less than 0.20 indicating the presence of collinearity.Unconditional logistic regression was used to calculate odds ratios (ORs), their corresponding 95% confidence intervals (CIs) and associated  smoking . SimilarP values were 2-sided. Values of P less than 0.05 were considered statistically significant.All analyses were conducted using SAS 9.4 . All


To investigate risk of premenopausal and postmenopausal breast cancer among Multiple Sclerosis (MS) patients, considering tumor stage.The Swedish Patient Register identified 19,330 women with MS between 1968 and 2012, matched individually with a cohort of 193,458 without MS. Matching variables were year of birth, sex, region of residence and vital status at the time of diagnosis. The cancer register identified 471 and 5,753 breast cancer cases among the MS and non-MS cohorts, respectively. Cox proportional hazard models estimated hazard ratios (HR) and 95% confidence intervals (CI) for premenopausal and postmenopausal breast cancer.Overall risk of postmenopausal breast cancer was 13% higher among MS patients compared with women without MS . Stratified analyses showed that the risk was statistically significantly increased in women diagnosed between 1968 and 1980 and those who were diagnosed at age 65 or older age. We observed a non-statistically significant risk only for stage 0–1 postmenopausal breast cancer . MS was not associated with premenopausal breast cancer.The modest increased risk of postmenopausal breast cancer in women with MS may be due to surveillance bias, where contact with health services for one disease increases the risk of a second diagnosis being recorded. Multiple Sclerosis is a chronic inflammatory disease of the central nervous system which is more common among the women, 2. AlthUsing Swedish population registers, we conducted a general population-based cohort study covering the period 1968 to 2012. Our aim was to assess the risk of breast cancer in MS patients, including categorization of breast cancer by menopausal status and tumor stage.All women who received a diagnosis of MS (primary or underlying diagnosis) in Sweden between 1968 and 2012 were identified, using data from the National Patient Register . The National Patient Register (NPR) has recorded hospital discharge diagnoses since 1964 with national coverage since 1987 and the current completeness of the register is more than 99%. Since 2Subjects with MS were individually matched with ten persons without the disease among the general Swedish population by Statistics Sweden (four cases had only 9 controls). The matching criteria were year of birth, sex, region of residence: residential province at the MS diagnosis and vital status at the time of the MS diagnosis . Subjects were excluded from the study if breast cancer was diagnosed before MS (n = 275) or the equivalent time in the comparison cohort (n = 2514). As there may be etiological differences for benign and malignant tumors, we investigated only malignant tumors: all benign tumors (50 MS patients and 601 non-MS comparators) and breast cancers that were diagnosed by autopsy (3 MS patients and 3 non-MS comparators) were excluded. The final number of study participants were 19,330 MS patients and 193,458 non-MS women.Age at cancer diagnosis, using 50 years as the cutoff , 18}, waThe study was approved by the research ethics committee of Karolinska Institutet.st Dec, 2012 whichever occurred first. We used time from the first diagnosis of MS registered in the Swedish Patient Register to the death, first migration, premenopausal breast cancer, postmenopausal breast cancer or end of study in Dec 31st, 2012, whichever occurred first, as the follow up time for postmenopausal breast cancer. Follow up time for the controls started from index date (the date of MS diagnosis in matched cases). Although persons are in fact not at risk for postmenopausal breast cancer before they are 50 years of age, the follow-up was started at the date of MS diagnosis to consider censoring due to other factors e.g. premenopausal breast cancer, emigration or death before age 50 years. We also performed a sensitivity analysis starting the follow-up at age 50 years and observed similar results. Person-years was calculated as the sum of the time difference between the entry dates and censoring events. We also reported incidence rates for categories of age at MS diagnosis and year of MS diagnosis. The 95% CIs for the IRs were calculated assuming that the observed events followed a Poisson distribution [We reported event count, person-years, and incidence rates with 95% confidence intervals for the occurrence of all breast cancer diagnoses, as well as divided into premenopausal and postmenopausal breast cancer. For premenopausal women follow up time started from the date of first MS diagnosis registered in the Swedish Patient Register to the death, first migration, premenopausal breast cancer, age 50 or end of study at 31Cox regression using follow-up years as the underlying time scale was used to estimate HR with 95% CI for premenopausal and postmenopausal breast cancer in women who were diagnosed with MS compared with the non-MS cohort. We adjusted the models for age, sex and region to take into account the matching criteria. The adjusted model provides greater statistical power and similar results to the stratified analysis. We used Cox proportional hazard models, which is a type of survival analysis that takes differences in follow-up time into account. Use of Cox regression gave us the opportunity to model several variables simultaneously and assess the risk through the study period, effectively taking age and other temporal effects into account. The multivariate models included educational level in addition to the matching factors. We categorized the age at MS diagnosis  and year of MS diagnosis  and estimated the risk for each subcategory separately. In analyses, stratified by tumor stage  the risk of premenopausal and postmenopausal breast cancer for MS patients was estimated. Since information on tumor stage was available from 2000, the data were restricted to events after this time for this sub-analysis using the date of MS diagnosis/index date as the start of follow up time. We investigated possible multiplicative interactions between MS and tumor stage separately in premenopausal- and postmenopausal diagnoses.We performed additional analyses restricting data to the periods before and after national coverage (from 1987), and the periods of national coverage for hospital discharge data; and with or without outpatient data (from 2001). We have built four different cohorts: MS patients who were diagnosed between 1968 and 1986; MS patients who were diagnosed between 1987 and 2000; the patients who were diagnosed after 2000; and MS patients who were diagnosed between 1987 and 2012. We reanalyzed the data based on these four cohorts. We also performed a sensitivity analysis starting the follow-up time five years before the date of MS diagnosis to account for the potential lag time between age of MS onset and diagnosis , 22. We,The proportionality assumption was verified for all models, by including a time-by covariate interaction in the model and testing the statistical significance.All analyses were preformed using SAS software version 9.4 Characteristics of the study population are described in This general population-based cohort study found an apparent risk increase for postmenopausal breast cancer, mainly stage 0–1, associated with MS but only among women with an MS diagnosis recorded at an older age. There was no association between MS and premenopausal breast cancers. We observed that the incidence rate of breast cancer in women without MS is 206 per 100,000 person-years which is consistent results from previous reports.Increased risk of breast cancer among MS patients was shown by some studies –7 but noThe results from our study show that the risk of breast cancer among MS patients is higher among patients who were diagnosed with MS at age 65 or older. Some previous studies , 31 haveStrengths of this study are the large sample size and the general population-based cohort design. Using Swedish national registers gave us an opportunity to have adequate information and enough statistical power to investigate the risk of premenopausal—and postmenopausal breast cancer among MS patients, taking stage of tumor into account. This study has also some potential limitations. Restricting the data to the date between 2000 and 2012 limited our statistical power. For this reason, we categorized tumor stage in three groups instead of using the standard classification. AnotherIn conclusion, patients with MS may have a moderately increased risk of postmenopausal breast cancer, but this might be due to surveillance bias rather than reflecting a true risk. MS does not appear to be associated with premenopausal breast cancer.S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.S4 Table(DOCX)Click here for additional data file.S5 Table(DOCX)Click here for additional data file.S6 Table(DOCX)Click here for additional data file.S7 Table(DOCX)Click here for additional data file.S8 Table(DOCX)Click here for additional data file.S9 Table(DOCX)Click here for additional data file.S10 Table(DOCX)Click here for additional data file.S11 Table(DOCX)Click here for additional data file.