Mature cystic teratoma (common in the ovary of the adult female). Mass with a large cyst occupying most of it; in its cavity there is sebaceous material and hairs. The wall, generally a few millimeters thick, has the structure of skin, with its epidermal surface towards the cavity. Because of this preponderant development of cutaneous structures it is usually called dermoid cyst. The tissues that compose the tumor are well differentiated (mature or adult type); apart from skin structures many other tissues can be observed, particularly in a thickening or spur that eminences into the cavity, in which there are often teeth, cartilage and bone.

20-year-old woman with ovarian tumor of 15 cm, solid-cystic, detected by ultrasound after presenting with unspecific abdominal symptoms. In the histopathological study of the corresponding specimen, teeth, hairs, areas of intestinal epithelium, areas of squamous epithelium (15%) and bronchial epithelium, as well as neuroectodermal and embryonic elements are found in several of the histological preparations. In reference to this case, point out the correct diagnosis:

Malignant transformation of ovarian mature cystic teratoma with a predominant pulmonary type small cell carcinoma component.

A 68-year-old woman was diagnosed with mature cystic teratoma of the left ovary when she was 44 years old. The tumor recently enlarged rapidly, and abdominal magnetic resonance imaging revealed an intrapelvic cystic lesion, which measured 123 × 120 × 107 mm and contained a mural nodule. Under a clinical diagnosis of malignant transformation of mature cystic teratoma, bilateral salpingo-oophorectomy with total hysterectomy and omentectomy were performed. The resected specimen showed a unilocular cystic lesion containing a well-demarcated mural nodule measuring 35 × 30 × 25 mm in the left ovary. A microscopic examination revealed various types of carcinoma in the mural nodule: pulmonary type small cell carcinoma (65%), adenocarcinoma (25%), squamous cell carcinoma (5%), and transitional cell carcinoma (5%). Small cell carcinoma was positive for CD56, synaptophysin, and chromogranin A. The adenocarcinoma component showed intestinal phenotypes; i.e. cytokeratin (CK) 7(-), CK20(+), CDX2(+), estrogen receptor(-), and progesterone receptor (-). Interestingly, CDX2 positivity was retained in all of the carcinomas. It was assumed that the adenocarcinoma had arisen from an intestinal epithelium in the mature cystic teratoma and then differentiated into the diverse histological types mentioned above.

A case of concomitant occurrence of struma ovarii and malignant transformation of cystic teratoma.

A 77-year-old woman received a total abdominal hysterectomy and bilateral salpingo-oophorectomy because of a tumor in the left ovary. The surgical specimen measured 8.5x4.5x4.0 cm, and the solid lesion measured 4.0x3.5x3.5 cm. The solid lesion was diagnosed as struma ovarii. The cyst wall partially comprised squamous epithelium-like and ciliated columnar epithelium-like cells. The tumorous lesion of the cyst wall revealed a poorly differentiated adenocarcinoma. Immunohistochemically, the tumor cells were positive for cytokeratin7, and were negative for cytokeratin20 and thyroid transcription factor-1. The authors diagnosed that struma ovarii and other parats coexisted as a poorly differentiated adenocarcinoma that had arisen from a mature ovarian cystic teratoma. As for the identification of the origin of adenocarcinomas arising from mature ovarian cystic teratomas, more cases need to be identified and investigated.

Adenocarcinoma arising from the respiratory ciliated epithelium in a benign cystic teratoma of the ovary.

Benign cystic teratoma of the ovary (BCTO) is the most common benign ovarian tumor, accounting for 15-20% of all ovarian tumors. It is usually diagnosed in the third and fourth decades of life. Malignant transformation is rare, occurring in approximately 1-2% of reported cases, with squamous cell carcinoma being the most common form. Adenocarcinoma arising from mature cystic teratoma is extremely rare. We present the patient with a BCTO, where a malignant transformation of respiratory ciliated epithelium resulted in well differentiated adenocarcinoma. Although respiratory epithelium is often found in BCTOs, adenocarcinoma arising from this cell type is uncommon. To our knowledge, this is the fourth reported case of adenocarcinoma arising from the respiratory epithelium of a BCTO.

A case of ovarian mature cystic teratoma presenting as a pedunculated ileal tumor.

We report on a 34-year-old Japanese woman who presented with a pedunculated ileal tumor and who was finally diagnosed as having a right ovarian mature cystic teratoma penetrating and protruding into the ileum. She had undergone laparoscopic left ovarian cystectomy, whose specimen was diagnosed as dermoid cyst when she was 27 years old. The colon fiberscope revealed an ileal polyp, diagnosed as mature teratoma. Because of adhesion to the necrotic nodule between the tumor and the right ovary, ileocecal resection and right ovarian cystectomy were performed. The ileal tumor contained tissues of skin, neuroglia, ganglion, choroid, retina, smooth muscle, as well as fibrous and adipose tissues, cartilage, bone, mucous epithelium, and bronchial structures with bronchial glands. The necrotic nodule showed abscess, granulation tissue, foreign body reaction, hairs, normal ileal epithelium, and the ovary with ovums.

Ovarian Teratoma in Routine Biopsy Material During a Five-Year Period.

Teratomas are tumors derived from germ cells, most frequently arising in the gonads. The aim of this study was to determine the number of ovarian teratomas diagnosed in the routine biopsy material at Ljudevit Jurak Clinical Department of Pathology, Sestre milosrdnice University Hospital Center during a 5-year period, as well as their clinical, gross and microscopic characteristics. Teratomas accounted for 48.6% (n=166) of primary ovarian tumors. The patient mean age was 34.74±12.37 years. Difference in the incidence of teratoma between the left and right ovary was not significant; bilateral teratoma was found in 13 patients. Teratomas were detected by ultrasonography in 115 (69.27%) cases and the rest were found during surgery performed for other indications. Most teratomas (n=161; 96.9%) were mature and cystic (dermoid cysts). Mature and solid teratomas were diagnosed in 5 (3.01%), ovarian struma in 2 (1.8%) cases and strumal carcinoid in 1 (1.2%) case. Mature cystic teratomas contained sebaceous material in 123 (76.8%) cases, and a total of 16 teeth were found; 157 (94.5%) teratomas measured <10 cm in largest diameter. Microscopically, mature cystic teratomas most frequently contained ectodermal (skin with appendages, mature glia and nerve ganglia) and mesodermal (fi brous, fat tissue, cartilage and bone) tissues. Frequently found tissues of endodermal origin were respiratory and intestinal epithelia. Small foci of thyroid tissue were found in 20 (12%) teratomas. Chronic granulomatous foreign body reaction in the wall of mature cystic teratomas was found in 11 (6.8%) tumors.

[Malignant transformation of thyroid tissue in an ovarian dermoid cyst: case report].

Mature cystic teratoma is the most common type of ovarian teratomas and also the most frequent tumor originating from germ cells. Usually unilateral, it is, by definition, composed of well-differentiated derivates which originate from all three layers. It is most frequently diagnosed in the female reproductive period; in its pure form, it is generally benign, but occasionally it may undergo malignant transformation in one of its elements. The authors report a case of a 43-year-old woman who underwent a thyroid regulation substitutive therapy 12 years after thyroidectomy which had been performed because of Basedow's disease. On the occasion of her fourth delivery by cesarean section, bilateral cystical formations in both ovaries were found. Upon ending the delivery, the right ovary with the cyst was surgically removed, as well as part of the cystically changed left ovary. The pathohistological analysis of the samples taken from the left ovary cyst pointed to the following diagnosis: dermoid cyst of the ovary a mature cystic teratoma, whereas the samples from the cystic tumor of the right ovary were diagnosed as: ovarian teratoma malignant a papillary carcinoma of the thyroid tissue and cystadenoma papillare serosum ovarii. The histological type of the malignant thyroid tissue neoplasm in the teratoma was a papillary carcinoma consisting of papillary proliferations lined by cuboidal, cylindrical and pseudostratified epithelium with charasteristic "ground glass" nuclei, but without invasion into the blood vessels. Malignant transformation of the ectopic thyroid tissue, which is one of the elements of the ovarian cystic teratoma, is extremely rare: it is diagnosed on basis of the histological picture and criteria which are the same as for the tumor of the thyroid gland. One should not exclude a pssibility that the identical or different pathological alterations characteristic of the thyroid gland may also be detected in the ectopic thyroid tissue of a dermoid cyst. The reported case was chosen due to its complex and rich clinical and pathohistological picture characterized by the occurrence of a bilateral dermoid cyst with the malignant transformation of the thyroid tissue. The malignant neoplasm in the mature ovarian cystic teratoma was papillary carcinoma of the thyroid tissue with all histological properties typical for the thyroid gland carcinoma. The possibility of the malignant transformation of the endodermal thyroid tissue in the mature ovarian cystic teratoma and changes in the thyroid gland of the Basedow's disease type diagnosed before are without clear causation.

Adenocarcinoma arising from respiratory ciliated epithelium in benign cystic teratoma of the ovary: a case report with analyzes of the CT, MRI, and pathological findings.

The malignant transformation of mature cystic teratoma is rare, thus occurring in only 1-2% of all cases. The most common malignancy arising in mature cystic teratoma is squamous cell carcinoma. Adenocarcinoma occurs with less frequency. We herein present a patient with an ovarian mature cystic teratoma who demonstrated a malignant transformation to well-differentiated adenocarcinoma. Malignant transformation was diagnosed preoperatively by contrast enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Microscopically and immunohistochemically, the adenocarcinoma was considered to have arisen from the ciliated respiratory epithelium. After a 28-month of follow-up period, she remains free of the disease. This is the third reported case of adenocarcinoma arising in the respiratory epithelium of an ovarian mature cystic teratoma. Contrast enhanced CT and MRI are useful for making a preoperative diagnosis and an immunohistochemical study is helpful for defining its origin.

Teratoma

Malignant transformation A "benign" grade 0 (mature) teratoma nonetheless has a risk of malignancy. Recurrence with malignant endodermal sinus tumor has been reported in cases of formerly benign mature teratoma, even in fetiform teratoma and fetus in fetu. Squamous cell carcinoma has been found in a mature cystic teratoma at the time of initial surgery. A grade 1 immature teratoma that appears to be benign (e.g., because AFP is not elevated) has a much higher risk of malignancy, and requires adequate follow-up. This grade of teratoma also may be difficult to diagnose correctly. It can be confused with other small round cell neoplasms such as neuroblastoma, small cell carcinoma of hypercalcemic type, primitive neuroectodermal tumor, Wilm's tumor, desmoplastic small round cell tumor, and non-Hodgkin lymphoma.

Ovarian cancer

Immature, or solid, teratomas are the most common type of ovarian germ cell tumor, making up 40–50% of cases. Teratomas are characterized by the presence of disorganized tissues arising from all three embryonic germ layers: ectoderm, mesoderm, and endoderm; immature teratomas also have undifferentiated stem cells that make them more malignant than mature teratomas (dermoid cysts). The different tissues are visible on gross pathology and often include bone, cartilage, hair, mucus, or sebum, but these tissues are not visible from the outside, which appears to be a solid mass with lobes and cysts. Histologically, they have large amounts of neuroectoderm organized into sheets and tubules along with glia; the amount of neural tissue determines the histologic grade. Immature teratomas usually only affect one ovary (10% co-occur with dermoid cysts) and usually metastasize throughout the peritoneum. They can also cause mature teratoma implants to grow throughout the abdomen in a disease

Well-differentiated cerebellum in an ovarian mature cystic teratoma: a case report and review of the literature.

Mature teratoma is the most common germ cell tumor as it represents 95% of germ cell tumors. Although common in children and young adults, ovarian teratoma can occur at any age. Mature teratomas are composed of mature tissues representing elements derived from more than one embryonic germ layer (ectoderm, mesoderm, and endoderm), with ectodermal derivatives being the usual predominant component; however, the finding of a well-differentiated cerebellum is extremely rare. A 20-year-old Saudi female presented to the emergency department with severe abdominal pain of 1-day duration. Pelvic ultrasound showed a large ovoid- to bilobed-shaped cystic pelvic structure extending to the lower abdomen. The patient underwent left ovarian cystectomy. Microscopic examination showed a cyst wall with skin tissue, including adnexal structures (sebaceous glands), a well-differentiated cerebellum, and mature glial tissue. After extensive sampling, no immature component was identified. Thus, the final diagnosis of a mature cystic teratoma with well-differentiated cerebellum was established. The patient was well postoperatively and was discharged in a stable condition. We report this case of well-differentiated cerebellum within ovarian teratoma to expand the pool of cases reported in literature of this extremely rare entity, as only 22 cases with such findings have been reported in literature to the best of our knowledge. This finding poses a diagnostic challenge to the pathologist due to its rarity and its similarity to immature teratoma. We thus emphasize that thorough sampling of ovarian teratoma is of paramount importance and to keep the aforementioned diagnosis in mind and not confuse it with immature elements, especially in intraoperative consultation and frozen sections.

Immature teratoma

An immature teratoma is a teratoma that contains anaplastic immature elements, and is often synonymous with malignant teratoma. A teratoma is a tumor of germ cell origin, containing tissues from more than one germ cell line, It can be ovarian or testicular in its origin. and are almost always benign. An immature teratoma is thus a very rare tumor, representing 1% of all teratomas, 1% of all ovarian cancers, and 35.6% of malignant ovarian germ cell tumors. It displays a specific age of incidence, occurring most frequently in the first two decades of life and almost never after menopause. Unlike a mature cystic teratoma, an immature teratoma contains immature or embryonic structures. It can coexist with mature cystic teratomas and can constitute of a combination of both adult and embryonic tissue. The most common symptoms noted are abdominal distension and masses. Prognosis and treatment options vary and largely depend on grade, stage and karyotype of the tumor itself.

Ovarian germ cell tumors

Teratomas Teratoma are most common germ cell tumor of ovary. Teratomas can be divided into two types: mature teratoma (benign) and immature teratoma (malignant). Immature teratomas contain immature or embryonic tissue which significantly differentiates them from mature teratomas as they carry dermoid cysts. It is commonly observed in 15 to 19-year-old women and rarely in women after menopause. Immature teratomas are characterized with a diameter of 14–25 cm, encapsulated mass, cystic areas, and occasional appearance of hemorrhagic areas. The stage of immature teratomas is determined depending on the amount of immature neuroepithelium tissue detected. Yolk sac tumor

[Pelvic retroperitoneal teratoma. A case report].

Teratomas are congenital tumors comprising of tissues arising from pluripotent embryonic cells. Their common sites of occurrences are ovary, testis, mediastinum and retroperitoneum. Retroperitoneal teratomas are extremely rare in adults but occur in 3% of children. The presence of a cystic or complex adnexal mass during pregnancy is common with mature teratoma reported in approximately 30-50% of pregnancies. The ultrasound is the number one method of detection. The use of tumor markers is limited because it alters its value during pregnancy. We report a case of a 18 year old female patient who came to the General Hospital Dr. Miguel Silva in Morelia, Michoacán with a gestation age of 10.2 weeks and a recent diagnosis of an asymptomatic adnexal mass. Using the transvaginal approach, the ultrasound reported an irregular gestational sac with the absence of cardiac activity in the embryo. A diffusely echogenic adnexal mass with oval appearance, wall regularity and homogeneous internal echos of 12.96 x 8.99 cm. Exploratory laparotomy was performed finding normal uterus and ovaries, with the posterior retroperitoneal resection of the 15 cm multi-lobed tumor. The surgical specimen measured 13 x 12 x 8 cm, had a brownish color, wall irregularity, soft consistency, multi-lobed, and a yellowish interior greasy material. Microscopically the tumor is delimited with a firm capsule composed of a hyaline-fibrous tissue, lined by squamous keratinized epithelium, with multiple layers of keratin. This anato-pathologic finding is diagnostic of retroperitoneum mature teratoma.

Adenocarcinoma arising from respiratory ciliated epithelium in mature ovarian cystic teratoma.

Malignant transformation of a mature cystic teratoma of the ovary is rare, that of an adenocarcinoma is extremely rare. A 32-year-old woman was suspected as having a malignant transformation of her mature cystic teratoma of the ovary because the preoperative level of carcinoembryonic antigen (CEA) was extremely high. Resections of her ovarian cysts were performed, and this particular tumor was histopathologically diagnosed as an adenocarcinoma arising from a mature cystic teratoma of the left ovary. Because adenocarcinomas arising from mature cystic teratomas of the ovary are extremely rare, we report this case with a review of some of the literature.

Ovarian cancer

Histologically, embryonal carcinoma appears similar to the embryonic disc, made up of epithelial, anaplastic cells in disorganized sheets, with gland-like spaces and papillary structures. Polyembryoma Polyembryomas, the most immature form of teratoma and very rare ovarian tumors, are histologically characterized by having several embryo-like bodies with structures resembling a germ disk, yolk sac, and amniotic sac. Syncytiotrophoblast giant cells also occur in polyembryomas. Squamous cell carcinoma Primary ovarian squamous cell carcinomas are rare and have a poor prognosis when advanced. More typically, ovarian squamous cell carcinomas are cervical metastases, areas of differentiation in an endometrioid tumor, or derived from a mature teratoma.

[Benign mature teratomas of the mediastinum].

Mature teratomas of the mediastinum are rare. However, they represent the most common mediastinal germ cell tumours. The aim of this study is to describe their clinical and pathological characteristics. Fourteen cases of mediastinal mature teratoma, diagnosed between January 1992 and December 2006, were reviewed retrospectively, noting the clinical, radiological, surgical, and pathological findings. The patient population consisted of 10 females and 4 males with mean age of 29 years (5-56 years). Chest pain was the main symptom. Imaging features comprised a heterogeneous anterior mediastinal mass containing soft-tissue, fluid, fat, or calcium attenuation, or any combination of the four. Macroscopically all the tumours were cystic, or predominantly cystic, containing mostly grumous material. The mean size was 9 cm (5-12 cm). Histological examination constantly revealed skin with or without appendages. Other components identified were bronchial mucosa (12 cases), fat (12 cases), muscle (10 cases), cartilage (8 cases), bone (7 cases), gastrointestinal mucosa (7 cases), pancreas (5 cases), urothelial epithelium (3 cases), nervous and prostatic tissues (one case each). All the teratomas were mature, and 7 of them were intrathymic. Every form of teratoma occurs in the mediastinum (mature, immature and with malignant transformation) but, in our study, they were exclusively mature. The histology is essentially similar to that of teratomas of gonads. However, pancreatic tissue occurs frequently in mediastinum (54% in literature, 25% in our study) but not in the gonads. On the other hand, thyroid follicles have not yet been seen in mediastinal teratomas.

Dermoid cyst

A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature, solid tissues. It frequently consists of skin, hair follicles, and sweat glands, while other commonly found components include clumps of long hair, pockets of sebum, blood, fat, bone, nail, teeth, eyes, cartilage, and thyroid tissue. As dermoid cysts grow slowly and contain mature tissue, this type of cystic teratoma is nearly always benign. In those rare cases wherein the dermoid cyst is malignant, a squamous cell carcinoma usually develops in adults, while infants and children usually present with an endodermal sinus tumor. Location Due to its classification, a dermoid cyst can occur wherever a teratoma can occur. Vaginal and ovarian dermoid cysts

Immature teratoma

Ovarian cancer is staged using the FIGO staging system and uses information obtained after surgery, which can include a total abdominal hysterectomy via midline laparotomy, unilateral (or bilateral) salpingo-oophorectomy, pelvic (peritoneal) washings, assessment of retroperitoneal lymph nodes and/or appendectomy. The AJCC staging system, identical to the FIGO staging system, describes the extent of tumor (T), the presence of absences of metastases to lymph nodes (N), the presence or absence of distant metastases (M). Pathology An immature teratoma contains varying compositions of adult and embryonic tissue. The most common embryonic component identified in immature teratomas is the neuroectoderm. Occasionally, tumors may present neuroepithelium that resemble neuroblasts. Tumors may also present embryonic components such as immature cartilage and skeletal muscle of mesodermal origin. Immature teratomas composed of embryonic endodermal derivatives are rare.

Morphological characteristics of different types of cystic teratoma of the ovary. A study of surface ultrastructure in relation to tumor classification and development.

In this study the surface ultrastructure of 28 cystic ovarian teratomas was examined to determine their morphological appearance and the relation to biological behavior. The squamous epithelium of cystic tumors showed abnormal maturation and keratinization of surface cells with keratinous flakes occasionally in polypoid configurations. The respiratory epithelium showed an abundance of microvillous and ciliated cells, areas with disorganized surface structures were also seen. Piling up of squamous cells in heaps, piles, cauliflower- or onion-like arrangements were seen in lesions histologically regular. This study showed a distinct difference in surface ultrastructure as compared to ovarian cystadenomas emphasizing the difference in development. Surface ultrastructural studies also were useful in deciding the nature of histologically indeterminable lesions as well as in revealing areas of malignant potential.

Teratoma

Types Mature teratoma A mature teratoma is a grade 0 teratoma. They are highly variable in form and histology, and may be solid, cystic, or a combination of the two. A mature teratoma often contains several different types of tissue such as skin, muscle, and bone. Skin may surround a cyst and grow abundant hair (see dermoid cyst). Mature teratomas generally are benign, with 0.17-2% of mature cystic teratomas becoming malignant. Immature teratoma Immature teratoma is the malignant counterpart of the mature teratoma and contains immature tissues which typically show primitive or embryonal neuroectodermal histopathology. Immature teratoma has one of the lowest rates of somatic mutation of any tumor type and results from one of five mechanisms of meiotic failure.

[Laparoscopic extirpation of retroperitoneal bronchogenic cyst].

The retroperitoneal bronchogenic cyst is an extremely rare anomaly. During the examination of an 18-year-old female patient due to her extreme thinness, the abdominal ultrasound and later the CT indicated as an accidental finding--a left side adrenal/suprarenal adenoma, which turned out to be hormonally inactive. But while we were doing a laparoscopic surgical intervention we found a 6-8-cm cyst in the retroperitoneum, between the greater curvature and the spleen. It contained light grey, mucinous liquid. The left suprarenal gland had normal size and appearance. During the microscopic examination the removed terime showed cystic structures, which were covered inside with multilayer ciliated columnar epithelium, mucous excretory glands, a whole layer of connective/interstitial and smooth muscle tissue. Neither cartilage, nor gastrointestinal epithelium was found. Only a few publications have reported about retroperitoneal bronchogenic cyst so far. These lesions occur very rarely at the greater curvature. Although this alteration is really unusual, bronchogenic cysts have to be expected in the differential diagnostics of the retroperitoneal tumors.

[Mature cystic teratoma of the ovary with a small ganglioneuroma].

A case of ganglioneuroma arising within a cystic mature teratoma of the ovary in a 34-year-old woman is reported. Patient underwent right adnexectomy. The ovary was completely replaced by a bilocular cystic lesion, measuring 8 cm in diameter and filled with adipose tissue and pilosebaceous material. Microscopically the cyst was composed by a mature cystic teratoma containing skin with dermal appendages, fatty tissue and bronchial epithelium. Furthermore a nodule (0.5 cm in size) composed of mature ganglion cells, axons and Schwann cells, was identified. Ganglion cells were positive for NSE and synaptophysin, while Schwann cells stained positively with S100 protein and GFAP. To the best of our knowledgment this is the first reported cases of ganglioneuroma arisen within a cystic mature teratoma of the ovary.

Primary Mature Teratoma of the Rectum: A Case Report.

BACKGROUND Teratomas are embryonal neoplasms that contain tissues derived from 1 or more of the 3 germ layers. They commonly are found in the sacrococcygeal-gonadal location, sometimes in midline locations such as the mediastinum, retroperitoneum, and head and neck region. Primary rectal teratomas are extremely rare. Extragonadal teratomas can originate from pluripotent germ cells present in abnormal embryonic rests. CASE REPORT Here, we report a rare case of a primary mature, solid teratoma of the rectum. A 68-year-old woman presented with hematochezia and denied any history of abdominal pain or a change in bowel habits. Colonoscopy revealed a 4-cm pedunculated polyp in the rectum. No hair was present on its surface. The polyp was completely removed by polypectomy. Histologically, the tumor consisted of mature components from all 3 germ layers. Its surface was covered by squamous epithelium with hair follicles and sweat glands. Adipose tissue, blood vessels, bone, and glandular epithelium were present inside the mass. No evidence was found of immature elements or malignant features. CONCLUSIONS When polypoid lesions are found in the rectum, teratoma should be considered in the differential diagnosis. Histopathological confirmation is necessary to diagnose teratoma. Primary rectal teratomas should be distinguished from other neoplastic polyps as well as from local spread of teratomas arising in adjacent organs. These neoplasms are usually mature (benign) but may undergo malignant transformation. Therefore, complete resection is recommended to alleviate symptoms and avoid the risk of malignancy.

[Mature benign teratomas with malignant tumors and malignant monodermal ovarian teratomas. Anatomo-clinical presentation of 10 cases].

The clinicopathologic features are presented of 8 malignant neoplasms occurring in adult teratomas, and of 2 malignant monodermal teratomas found in a continuous series of 1029 cases of ovarian adult teratomas. The age of the patients was 44--76 years. The first 8 observations included 6 epidermoid carcinomas, 1 undifferentiated carcinoma and 1 strumal carcinoid. In the epidermoid carcinomas malignancy was recognized peroperatively only in three instances. One tumor had infiltrated the broad ligament on one side and another the urinary bladder. The neoplasm appeared as a mass which thickened the wall of a typical dermoid cyst. Four patients died of the tumor from 3 months to 1 year after operation; one is alive more than 19 years later and one is lost to follow-up. The crucial factor in prognosis is the integrity of the ovarian capsule. The undifferentiated carcinoma, which had infiltrated the pelvic walls, could only be incompletely resected and caused death within 3 1/2 months. The strumal carcinoid was discovered by chance during laparotomy for a far-advanced adenocarcinoma of the pancreas which led to death within 2 months. The two cases of malignant monodermal teratoma comprised 1 thyroid papillary carcinoma and 1 carcinoid. Both patients are alive more than 8 and 5 years after operation. The carcinoid manifested itself by persistant diarrhea which ceased soon after operation and did not recur subsequently.

International Classification of Diseases for Oncology

M9064/3 Germinoma Germ cell tumor, NOS M9065/3 Germ cell tumor, nonseminomatous M9070/3 Embryonal carcinoma, NOS Embryonal adenocarcinoma M9071/3 Yolk sac tumor Endodermal sinus tumor Polyvesicular vitelline tumor Orchioblastoma Embryonal carcinoma, infantile Hepatoid yolk sac tumor M9072/3 Polyembryoma Embryonal carcinoma, polyembryonal type M9073/1 Gonadoblastoma Gonocytoma M9080/0 Teratoma, benign Adult cystic teratoma Adult/cystic teratoma, NOS Teratoma, differentiated Mature teratoma M9080/1 Teratoma, NOS Solid teratoma M9080/3 Teratoma, malignant, NOS Embryonal teratoma Teratoblastoma, malignant Immature teratoma, malignant or NOS M9081/3 Teratocarcinoma Mixed embryonal carcinoma and teratoma M9082/3 malignant teratoma, undifferentiated Malignant teratoma, anaplastic M9083/3 Malignant teratoma, intermediate M9084/0 Dermoid cyst, NOS Dermoid, NOS

Clinicopathological observation of mature teratoma with malignant transformation, a single center retrospective study.

To investigate the clinicopathological features of mature teratoma with malignant transformation. Retrospectively analysis of 1179 cases mature teratoma was done from August 1999 to December 2019 in Institution. 14 cases of mature teratoma with malignant transformation were discussed mainly for the pathological characteristics and clinical manifestations. 4 of them were less than 40 years old. All but one occurred in the ovaries, and the one was in the left anterior mediastinum which was the only male. The clinical manifestations of the patients were atypical. Imaging showed cystic solid mass. Surgery was performed. Polypoid mass, solid nodule and thickened area of cyst wall can be seen on the section of tumor. Pathological results show that there were 5 cases of squamous cell carcinoma, 3 cases of carcinoid, 2 cases of serous carcinoma and 2 cases of thyroid papillary carcinoma, 1 case of carcinosarcoma and 1 case of strumal carcinoid. Two cases of squamous cell carcinoma had pelvic and abdominal metastasis. Immunohistochemistry of case 14 showed that AE1/AE3, CD56, SYN, NSE, PSAP, CDX2 were positive in carcinoid. EMA and CK20 were positive in mucinous glands around carcinoid. Calretinin and inhibin were positive in the mesenchyme adjacent to intestinal mucinous gland. Teratoma with malignant transformation is a rare malignancy, although teratoma is a common germ cell tumor. And it's more common in patients over 40 years, especially those patients who were in menopause. Squamous cell carcinoma is the most common type and prone to metastasis. Strumal carcinoid was well-defined, but as an endocrine tumor, it may cause a series of digestive, respiratory or hormonal disorders. Therefore, the mature teratomas should be removed in time after detection.

Pulmonary blastoma. Comparison between its epithelial components and fetal bronchial epithelium.

Three cases of pulmonary blastoma exhibiting biphasic epithelial and stromal patterns, and a case of fetal lung-type adenocarcinoma, were examined by immunohistochemistry and electron microscopy (EM) and compared with fetal bronchial epithelium in order to explore the multidirectional differentiation of their epithelial components. The glandular cells of all four tumors resembled fetal bronchial epithelial cells in the pseudoglandular stage. Neuroendocrine (NE) cells were also present; they were argyrophilic and expressed pan-NE markers, neurosecretory granules and peptide hormones. The neural cell adhesion molecule (NCAM) was strongly expressed on the cell membranes of glandular cells, as in the case of proximal bronchial epithelial cells at the pseudoglandular stage in fetal lung. Sialosylated Lewis X was also expressed, indicating that the epithelial cells were possibly of endodermal origin. Two of the four cases showed considerable immunoreactivity for alpha-fetoprotein (AFP). The epithelial cells of pulmonary blastomas may occasionally de-differentiate into cells functionally resembling fetal hepatic, foregut and yolk sac cells expressing AFP. Tumor examination by immunohistochemistry and EM suggested that the glandular cells of the tumors may differentiate to some extent like those of fetal large bronchi at the pseudoglandular stage, but there was concordance and discordance in the expression of neuroendocrine and oncofetal markers between blastomatous tumors and fetal bronchial epithelium.

An intrapulmonary teratoma associated with bronchiectasia containing various kinds of primordium: a case report and review of the literature.

An intrapulmonary teratoma (IPT), multiloculated and bronchiectatic, with two polyps inside a 23-year-old man is reported. The IPT, a very rare benign cystic lesion, was communicating with segmental bronchus and was removed by a segmental resection from the upper lobe of the left lung. The teratoma contained various kinds of primordial derivatives, such as mesoderm, ectoderm, and endoderm. Though 65 cases of IPT have been reported in the literature (1839-1996), in the present case there were over 15 germ derivatives, the largest number reported to date. The tumor contained thymic tissue, apart from mediastinum, which may be significant in relation to the pathogenesis of IPT. Clinical manifestations, age, and gender distributions and the kind of germ cell derivatives are discussed.

Benign cystic teratoma of the parotid gland: a case report.

Mature cystic teratomas of the major salivary glands are rare. This report describes a case of a mature cystic teratoma of the left parotid gland, including the cytologic and histopathologic findings. A 17-year-old young woman presented with a slow-growing left parotid mass that had been present for 4 years. Preoperative fine needle aspiration cytology showed the presence of acinar and ductal cells, foamy cells and multinucleated giant cells. Imprint cytology of the surgical material showed the presence of some squamous cells and sebaceous gland-like cells with hair shafts. Cellular atypia was inconspicuous. Grossly, the 3-cm lesion was unicystic and embedded within the parotid gland parenchyma. Microscopically, the inner surface of the cyst was lined with keratinized squamous epithelium. The cyst wall contained skin adnexa such as sebaceous, eccrine and apocrine glands, as well as hair follicles. Some mature cartilage tissue was also detected. Foreign body granulomatous change was seen focally. No immature tissue or malignant transformation was found. There is no previous report describing the cytologic findings of a mature cystic teratoma of the parotid gland. Mature cystic teratomas should therefore be considered in the differential diagnosis of a cystic lesion of the parotid

[Primary malignant teratoma of the thyroid. Two cases involving immunohistochemical and ultrastructural studies].

Two cases of primary malignant teratoma of the thyroid are reported. The first case, which occurred in a 21-year-old female, was mostly composed of tumoral neural tissue and foci of foetal cartilage. The patient died with lung metastases within 5 months after the first symptoms. The second case, which occurred is a 8-year-old infant female, had epithelial and mesenchymal components without neural tissue. This case had a better prognosis with survival of four years after initial diagnosis. The different tumoral components were identified by a thorough histopathological examination of the thyroidectomy with immunological and ultrastructural studies. As for other teratomas, presence of immature neural tissue bore a poor prognosis. The clinical, histopathological features and the histogenesis of this rare tumour are described and literature is reviewed.

Ovarian Small Cell Carcinoma of Pulmonary Type Arising in Mature Cystic Teratomas With Metastases to the Contralateral Ovary.

A bilateral small cell ovarian carcinoma pulmonary-type (SCCOPT), arising in bilateral mature cystic teratomas (MCTs) presented as stage IIIB in a 37-year-old woman. Microscopically, tumor nests were related to the dermoid protuberance and expressed pancytokeratin, EMA, CD56, chromogranin A, NSE, synaptophysin, and SOX2. SALL4 was also focally positive. CDX2, TTF1, PAX8, CK7, CK20, and several neuroendocrine gut hormones were negative. Serum NSE was elevated. This case represents a SCCOPT arising in an MCT in the right ovary with metastasis to the left one also containing a synchronous MCT. Surface implants and lymphovascular invasion suggested metastasis from the right ovarian SCCOPT and excluded a metastatic origin from usual locations of small cell carcinoma (SCC). SCCOPT is morphologically identical to SCC elsewhere, even sharing NSE serum elevation. Although the tumor was closely related to teratomatous mature tissues, a complex immunohistochemical panel failed to provide a tissue of origin.

Testicular Teratoma -- Histopathology

Microscopy : Any epithelial, mesenchymal, or neural-derived tissue can be seen. Less common are tissues derived from the respiratory, gastrointestinal, or genitourinary tract. Skin-derived structures such as epithelial-derived (epidermoid cyst) or appendages is a quite common finding, especially in prepubertal-type teratomas, while postpubertal-type teratomas tend to appear as multiloculated cysts lined by other tissue types such as glandular epithelium and contain solid areas formed by parenchymal structure or mesenchymal tissues. A certain element of immature tissues can also be encountered, consisting of ectodermal, endodermal, or mesenchymal structures. Neuroectodermal tissue is the most common immature type and often has several differentiation stages of embryonic/fetal nervous system tissue. Historically teratoma has been differentiated into mature and immature, but this distinction is not recommended any more due to the lack of a prognostic significance. Teratoma can occur paired with other histotypes of germ cell neoplasia, such as yolk sac tumor or embryonal carcinoma.