Primordial germ cells as a potential shared cell of origin for mucinous cystic neoplasms of the pancreas and mucinous ovarian tumors.

Mucinous ovarian tumors (MOTs) morphologically and epidemiologically resemble mucinous cystic neoplasms (MCNs) of the pancreas, sharing a similar stroma and both occurring disproportionately among young females. Additionally, MOTs and MCNs share similar clinical characteristics and immunohistochemical phenotypes. Exome sequencing has revealed frequent recurrent mutations in KRAS and RNF43 in both MOTs and MCNs. The cell of origin for these tumors remains unclear, but MOTs sometimes arise in the context of mature cystic teratomas and other primordial germ cell (PGC) tumors. We undertook the present study to investigate whether non-teratoma-associated MOTs and MCNs share a common cell of origin. Comparisons of the gene expression profiles of MOTs [including both the mucinous borderline ovarian tumors (MBOTs) and invasive mucinous ovarian carcinomas (MOCs)], high-grade serous ovarian carcinomas, ovarian surface epithelium, Fallopian tube epithelium, normal pancreatic tissue, pancreatic duct adenocarcinomas, MCNs, and single-cell RNA-sequencing of PGCs revealed that both MOTs and MCNs are more closely related to PGCs than to either eutopic epithelial tumors or normal epithelia. We hypothesize that MCNs may arise from PGCs that stopped in the dorsal pancreas during their descent to the gonads during early human embryogenesis, while MOTs arise from PGCs in the ovary. Together, these data suggest a common pathway for the development of MCNs and MOTs, and suggest that these tumors may be more properly classified as germ cell tumor variants. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Fetiform Teratoma in the Ovary of a 7-Year-Old Girl: A Case Report.

BACKGROUND: Fetiform teratoma, a highly differentiated mature cystic teratoma resembling a fetus, is rare and typically found in the ovaries of women of reproductive age. In this report we describe, to our knowledge, the youngest case of ovarian fetiform teratoma. CASE: A 7-year-old girl presented with acute abdominal pain. Radiological examinations revealed a 5.2-cm ovarian complex cystic mass with fetal-like components in favor of fetus in fetu and teratoma. After surgical removal, the mass resembled a fetus consisting of a head, two eye slits, two small upper limb projections, and hair. Pathology indicated mature cystic teratoma supporting the diagnosis of fetiform teratoma. SUMMARY AND CONCLUSION: Although not commonly found in children, fetiform teratoma must be considered in the diagnosis of a child who presents with an adnexal mass resembling a fetus.

The role of reproductive hormones in epithelial ovarian carcinogenesis.

Epithelial ovarian cancer comprises ∼85% of all ovarian cancer cases. Despite acceptance regarding the influence of reproductive hormones on ovarian cancer risk and considerable advances in the understanding of epithelial ovarian carcinogenesis on a molecular level, complete understanding of the biologic processes underlying malignant transformation of ovarian surface epithelium is lacking. Various hypotheses have been proposed over the past several decades to explain the etiology of the disease. The role of reproductive hormones in epithelial ovarian carcinogenesis remains a key topic of research. Primary questions in the field of ovarian cancer biology center on its developmental cell of origin, the positive and negative effects of each class of hormones on ovarian cancer initiation and progression, and the role of the immune system in the ovarian cancer microenvironment. The development of the female reproductive tract is dictated by the hormonal milieu during embryogenesis. Intensive research efforts have revealed that ovarian cancer is a heterogenous disease that may develop from multiple extra-ovarian tissues, including both Müllerian (fallopian tubes, endometrium) and non-Müllerian structures (gastrointestinal tissue), contributing to its heterogeneity and distinct histologic subtypes. The mechanism underlying ovarian localization, however, remains unclear. Here, we discuss the role of reproductive hormones in influencing the immune system and tipping the balance against or in favor of developing ovarian cancer. We comment on animal models that are critical for experimentally validating existing hypotheses in key areas of endocrine research and useful for preclinical drug development. Finally, we address emerging therapeutic trends directed against ovarian cancer.

Dietary fat intake and risk of epithelial ovarian cancer by tumour histology.

BACKGROUND: Studies of fat intake and epithelial ovarian cancer (EOC) risk have reported inconsistent findings, hence we hypothesised that associations may vary by histologic subtype. METHODS: We evaluated fat intake in a New England case-control study including 1872 cases and 1978 population-based controls (1992-2008). Epithelial ovarian cancer risk factors and diet were assessed using a food frequency questionnaire at enrolment. Logistic regression was used to estimate associations between fat intake and EOC risk and polytomous logistic regression was used to test whether associations varied by histologic subtype. RESULTS: We observed a decreased risk of EOC when comparing the highest vs lowest quartiles of intake of omega-3 (odds ratio (OR)=0.79, 95% confidence interval (CI) 0.66-0.96, P-trend=0.01) and omega-6 (OR=0.77, 95% CI 0.64-0.94, P-trend=0.02) and an increased risk with high consumption of trans fat (OR=1.30, 95% CI 1.08-1.57, P-trend=0.002). There was no significant heterogeneity by tumour histologic subtype; however, we observed a strong decreased risk for endometrioid invasive tumours with high intake of omega-3 (quartile (Q) 4 vs Q1, OR=0.58, 95% CI 0.41-0.82, P-trend=0.003). CONCLUSIONS: These findings suggest that higher intake of omega-3 may be protective for EOC overall and endometrioid tumours in particular, whereas greater consumption of trans fat may increase risk of EOC overall.

Low-grade serous carcinoma: new concepts and emerging therapies.

For the past several years, all women with epithelial ovarian cancer have been treated identically, whether in a clinical trial or off protocol. Over the past decade, we have come to appreciate the magnitude of the heterogeneity of ovarian cancer. The development of the binary grading system for serous carcinoma was a major advance leading to separate clinical trials for patients with this subtype originating from the Gynecologic Oncology Group's Rare Tumor Committee. The mitogen-activated protein kinase (MAPK) pathway appears to play a prominent role in the pathogenesis of this subtype. Approximately 20-40% of low-grade serous carcinomas have a KRAS mutation, while BRAF mutations are rare - about 5%. Primary treatment of low-grade serous carcinoma includes surgery+platinum-based chemotherapy (either adjuvant or neoadjuvant). Clinical behavior is characterized by young age at diagnosis, relative chemoresistance, and prolonged overall survival. Current options for treatment of relapsed disease include secondary cytoreduction in selected patients, salvage chemotherapy, or hormonal therapy. A recently completed trial of a MEK inhibitor for women with recurrent disease demonstrated promising activity. Future directions will include further investigations of the molecular biology and biomarker-driven clinical trials with targeted agent monotherapy and combinations.

Clinical characteristics of ovarian teratoma: age-focused retrospective analysis of 580 cases.

OBJECTIVE: The objective of the study was to evaluate the clinical characteristics of ovarian teratoma by age. STUDY DESIGN: This was a retrospective study. Five hundred eighty medical records were reviewed from patients who underwent operative removal of ovarian teratomas at Samsung Medical Center between January 1996 and February 2010. RESULTS: The proportion of asymptomatic patients increased significantly after 20 years of age (P = .0006). Ovarian torsion was noted in 26 patients (4.9%), without an age-specific difference (P = .5019; range, 0.0-8.2%). Tumor size was different according to age group (P < .0001), with larger tumor size in younger patients (<20 years old) relative to older patients. Immature teratoma revealed a higher incidence of symptomatic tumors on the first visit and significantly larger tumor size (P = .0004) compared with mature teratoma. CONCLUSION: Patients with ovarian teratoma have different clinical manifestations by age. It could help us understand clinical characteristics of the disease.

BAX-mediated cell death affects early germ cell loss and incidence of testicular teratomas in Dnd1(Ter/Ter) mice.

A homozygous nonsense mutation (Ter) in murine Dnd1 (Dnd1(Ter/Ter)) results in a significant early loss of primordial germ cells (PGCs) prior to colonization of the gonad in both sexes and all genetic backgrounds tested. The same mutation also leads to testicular teratomas only on the 129Sv/J background. Male mutants on other genetic backgrounds ultimately lose all PGCs with no incidence of teratoma formation. It is not clear how these PGCs are lost or what factors directly control the strain-specific phenotype variation. To determine the mechanism underlying early PGC loss we crossed Dnd1(Ter/Ter) embryos to a Bax-null background and found that germ cells were partially rescued. Surprisingly, on a mixed genetic background, rescued male germ cells also generated fully developed teratomas at a high rate. Double-mutant females on a mixed background did not develop teratomas, but were fertile and produced viable off-spring. However, when Dnd1(Ter/Ter) XX germ cells developed in a testicular environment they gave rise to the same neoplastic clusters as mutant XY germ cells in a testis. We conclude that BAX-mediated apoptosis plays a role in early germ cell loss and protects from testicular teratoma formation on a mixed genetic background.

[Ovarian adenosarcoma with elevated CA125 antigen. Case report and literature review]. / Adenosarcoma de ovario asociado con elevación del antígeno sérico Ca-125. Informe de caso y revisión de literatura.

BACKGROUND: Adenosarcomas are rare tumors usually derived from the endometrium. About 50 cases of adenosarcomas of the ovary have been reported. The relationship between adenosarcoma and CA125 has not been described. The authors present a case of adenosarcoma with elevated CA125 because of the unusual presentation of this pathology and also because elevation of the CA125 antigen has not been reported in the literature. CLINICAL CASE: A 42-year-old woman presented for consultation for incidental right ovarian tumor and CA125 of 1100 U/mL. Histology revealed a homologous Müllerian adenosarcoma of the right ovary with sarcomatous overgrowth. CA125 decreased to 16 U/mL after surgery. Sixteen months post-surgery, the patient is disease free and with normal CA125. DISCUSSION: Ovarian adenosarcomas are more aggressive than adenosarcomas of the uterus. Because of the embryological origin, ovarian adenosarcomas are able to produce CA125 antigen, especially in the presence of sarcomatous overgrowth. With these facts, CA125 antigen may be useful as a prognostic factor because it may represent an indirect marker of sarcomatous overgrowth. CONCLUSIONS: CA125 may be useful for follow-up of ovarian adenosarcomas. Elevated CA125 antigen in adenosarcomas of the ovary may be indicative of sarcomatous overgrowth and poor prognosis.

Adenosarcoma de ovario asociado con elevación del antígeno sérico Ca-125: informe de caso y revisión de literatura / Ovarian adenosarcoma with elevated CA125 antigen: case report and literature review

BACKGROUND: Adenosarcomas are rare tumors usually derived from the endometrium. About 50 cases of adenosarcomas of the ovary have been reported. The relationship between adenosarcoma and CA125 has not been described. The authors present a case of adenosarcoma with elevated CA125 because of the unusual presentation of this pathology and also because elevation of the CA125 antigen has not been reported in the literature. CLINICAL CASE: A 42-year-old woman presented for consultation for incidental right ovarian tumor and CA125 of 1100 U/mL. Histology revealed a homologous Müllerian adenosarcoma of the right ovary with sarcomatous overgrowth. CA125 decreased to 16 U/mL after surgery. Sixteen months post-surgery, the patient is disease free and with normal CA125. DISCUSSION: Ovarian adenosarcomas are more aggressive than adenosarcomas of the uterus. Because of the embryological origin, ovarian adenosarcomas are able to produce CA125 antigen, especially in the presence of sarcomatous overgrowth. With these facts, CA125 antigen may be useful as a prognostic factor because it may represent an indirect marker of sarcomatous overgrowth. CONCLUSIONS: CA125 may be useful for follow-up of ovarian adenosarcomas. Elevated CA125 antigen in adenosarcomas of the ovary may be indicative of sarcomatous overgrowth and poor prognosis.

Diagnostic challenge of fetal ontogeny and its application on the ovarian teratomas.

Although neuroepithelial tubules (NET) often are a component of immature teratoma (IT), they are not always required for diagnosis. Other somatic elements are sufficient and often verified with immunohistochemical stain. This study was designed to determine the definition of immaturity versus fetal ontogeny, using several molecular markers in IT. It is our contention that IT is equivalent to an embryonic stage less than a fertilization age (FA) of 8 weeks, and a mature teratoma (MT) to a fetal stage later than a FA of 8 weeks, whereas an embryonal carcinoma (Eca) matches a pre-embryonic stage earlier than a FA of 2 weeks. The teratomatous components used as a roadmap to evaluate maturity included: a lobular structure of primitive endodermal tubules (FA 4 to 6 weeks), a ventricle-lined cortical plate (FA 9 weeks), a complex papillary choroid plexus (FA 10 weeks), melanin deposition in hair follicles (FA 15 weeks), and the bell stage of odontogenesis (FA 19 weeks). The teratomatous components of 25 resected ovarian solid teratoma samples were compared with fetal ontogeny. For an immunohistochemical analysis, the CD30, CD34, CD99, bcl-2, alpha-fetoprotein (AFP), and placenta-like alkaline phosphatase (PLAP) were assessed. The AFP and Ki-1 were positive in the embryoid body, which was identified at a FA less than 4 weeks in Eca. The AFP was positive in the primitive endodermal components and some of the squamous epithelium in IT. The CD99 and bcl-2 were selectively stained in the primitive NET, which was detected no later than a FA of 6 weeks. The CD34 and bcl-2 were positive in the immature-looking precartilage blastomatous components, which proved useful for detecting immature cartilage, corresponding to a FA of 5 to 6 weeks. The ontogeny of IT was found to correspond to the embryonic stage at a FA of 2 to 8 weeks, and CD99, CD34, bcl-2, AFP, CD30, and PLAP could be used as supportive tools to define IT. This new grading system could be more scientific and more reproducible in any spectra of teratoma.

[Fetal ovarian cyst. A report of a case]. / Quiste de ovario fetal. Presentación de un caso.

Fetal ovarian cyst is uncommon; it represents the second place of fetal abdominal tumors, after urinary tract tumors. The cause of fetal ovarian cysts still remains unclear, although it is likely to be promoted by hormones. Its prognosis is usually good. Differential diagnosis should rule out urinary tract malformations. A case of a female newborn with giant fetal ovarian cyst, diagnosed on week 37 of the pregnancy period, treated with exploratory laparotomy and cyst exeresis, with serum cystadenoma histopathology diagnosis is presented.

[Cystadenomas with ovarian stroma in liver and pancreas: indications of embryonic migration of the gonadal epithelium]. / Cystadenomen met ovarieel stroma in lever en pancreas: aanwijzingen voor embryonale migratie van gonadaal epitheel.

OBJECTIVE: To provide an embryological explanation for the presence of ovarian stroma in cystadenomas of the liver and pancreas. DESIGN: Investigation of patients and embryos. METHOD: From 1997 to 2001 in the Academic Medical Centre, Amsterdam, the Netherlands, nine women were treated for a cystadenoma with ovarian stroma, six of which were situated in the liver and three in the tail of pancreas. In one patient with a cystadenoma in the liver, malignant changes had taken place. In embryos at 5-8 weeks development, the regional differences in the morphology of the epithelium of the peritoneal cavity and the position of the gonads in relation to the embryonic liver, pancreas and spleen were examined. RESULTS: In the foetal period before the gonads begin to descend, they are situated directly dorsal to the liver, tail of pancreas and spleen, but are separated from these by the peritoneal cavity. The cells that cover the urogenital folds distinguish themselves from those elsewhere in the peritoneal cavity as they are bulging in shape as opposed to flattened. This activated morphology suggests that on physical contact with a neighbouring organ the cells covering the gonads may become detached and lodge in that organ. CONCLUSION: It is likely that cystadenomas of the liver and pancreas have their origin in the cells that cover the embryonic gonads. The anomalous morphology of these covering cells in fact suggests that they are relatively easily mobilized. They are probably comparable with inoculation metastasis in the coelomic cavity. Taking the chance of malignant transformation of a cystadenoma into account, the treatment of choice is radical resection of the abnormality.

Spectrum of germ cell tumors: from head to toe.

Germ cell tumors (GCTs) occur most frequently in the gonads and are relatively rare in other sites, such as the pineal gland, neurohypophysis, mediastinum, and retroperitoneum. GCTs are thought to originate from primordial germ cells, which migrate to the primitive gonadal glands in the urogenital ridge. Extragonadal GCTs might also originate from these cells when the cells are sequestered during their migration. Pathologic subtypes of GCTs vary, and the prevalence of mixed tumors is high. These factors produce a diversity of radiologic findings and make prospective radiologic diagnosis difficult in many cases. However, similar radiologic findings have been observed in pathologically equivalent tumors in varying sites. Seminomas appear as uniformly solid, lobulated masses with fibrovascular septa that enhance intensely. Nonseminomatous GCTs appear as heterogeneous masses with areas of necrosis, hemorrhage, or cystic degeneration. Fat and calcifications are hallmarks of teratomas, most of which are benign. In immature teratomas, scattered fat and calcification within larger solid components are occasionally seen. These imaging characteristics reflect the pathologic features of each tumor, and histologically similar GCTs at varying sites have similar radiologic features. Knowledge of the pathologic appearances of GCTs and their corresponding radiologic appearances will allow radiologists to diagnose these tumors correctly.

Ovarian teratomas associated with the insertion of an imprinted transgene.

Ovarian teratomas are tumors that arise from female germ cells and are often a mixture of immature embryonal carcinoma cells and mature embryonic cells. Tissues derived from all three primary embryonic lineages (ectoderm, mesoderm, and endoderm) are typically found in the mature elements of a teratoma. In the case of the transgenic mouse line TG.KD, created with an imprinted transgene construct, malignant ovarian teratomas of a mixed germ cell tumor morphology occur in 15-20% of hemizygous female carriers of the transgene. The tumors frequently metastasize and can result in death of the mouse. Genetic analysis indicates that the tumors are associated with the transgenes integration site. Inbred FVB/N and female mice of other transgenic lines, also created in the inbred FVB/N strain with the same DNA construct as TG.KD, do not develop teratomas. In addition to teratomas, the integration of the transgene on Chromosome (Chr) 8 is associated with a perinatal lethality in homozygous transgenic carriers. The hemizygous genotypes of the teratomas suggest that they arise from early germ cells, prior to the completion of meiosis I.

Two cases of twisted fetal ovarian cysts.

Two twisted fetal ovarian cysts were detected antenatally by routine ultrasonographic examination. Serial changes of twisted ovarian cysts can be monitored by ultrasonic observation. If signs of torsion appear, obstetricians should consider prompt delivery in order to preserve the patient's fertility.

[Classification of ovarian tumors based on embryogenesis]. / Classification des tumeurs de l'ovaire basée sur l'embryogenèse.

This paper studies gonadal differentiation into the ovary from the earliest interaction between germ cells and somatic cells in the developing urogenital ridge up to the formation of primordial follicles. Granulosa cells appear to be derived from the breaking down of the cordlike arrangement of epithelial cells resulting from proliferation of surface coelomic mesothelium. Thecal cells arise from mesenchymal progenitors cells in the ovarian stroma. Based on the findings of embryology and biology, the authors then propose a classification of ovarian tumors by rearranging the WHO classification.

Immature endodermal teratoma of the ovary: embryologic correlations and immunohistochemistry.

Two grade 2 ovarian immature, predominantly endodermal teratomas are reported. The teratomas were in stage I and occurred in two girls, 9 and 10 years of age, who were treated with triple chemotherapy. These neoplasms differed from the usual immature ovarian teratoma as they contained no neuroectodermal components and had high alpha-fetoprotein and low human chorionic gonadotropin levels as their serum markers despite the absence of other concomitant germ cell tumors. The epithelia of the teratomas demonstrated exclusively the embryologic development of endoderm, ranging from early endoderm to tissues similar to esophagus, liver, and intestinal structures. All epithelial derivatives were positive for alpha-fetoprotein and alpha 1-antitrypsin. Liver and esophagus expressed fibrinogen, while intestine and esophagus were positive not only for carcinoembryonic antigen and chromogranins but also for thyroglobulin, thus reflecting yet another type of endodermal differentiation into thyroid. Focal human chorionic gonadotropin positivity associated with primitive intestinal and esophageal epithelia may reflect the early embryologic relationships between endoderm and trophoblast. These cases demonstrate that simultaneous alpha-fetoprotein and human chorionic gonadotropin secretion may occur in immature teratoma. The mesenchymal component also showed a wide range of differentiation, from primitive mesoblastic cells to differentiated cells, such as hemopoietic foci, smooth muscle, bone, and cartilage. Both the primitive endoderm and the mesenchyme co-expressed vimentin and keratin, reflecting their intimate developmental relationships and possibly supporting the hypothesis of mesenchyme originating from endoderm, as suggested by previous embryologic studies. Since endodermal and mesenchymal areas similar to those described here are found in association with yolk sac tumors and embryonal carcinoma, it is possible that the present cases may represent an endodermal differentiation accomplished by either of these developmentally related germ cell tumors.

Three-dimensional growth and differentiation of ovarian tumor cell line in high aspect rotating-wall vessel: morphologic and embryologic considerations.

Cancer of the ovary is the leading cause of death from gynecologic malignancy. To understand better these aggressive tumors, the development of in vitro models to study human ovarian cancer is critical. However, the establishment of long-term cell lines has been difficult, due to the generalized poor survival of patient tumor cells grown in primary culture. Satisfactory culture systems for ovarian tumor cells have therefore been limited. To study cellular interactions involved in the growth and differentiation of these tumors, a cell line was established from a mixed müllerian tumor of the ovary. This cell line, designated LN1, was cultured on microcarrier beads in the high aspect rotating-wall vessel. The tumor cells grown in this vessel readily proliferated without a requirement for cocultivation with a supportive cell layer. Evaluation of cellular morphology by phase contrast light microscopy and scanning electron microscopy revealed the presence of three-dimensional multicellular aggregates consisting of multiple cell-coated beads bridged together, as well as scattered aggregates of LN1 cells proliferating as spheroids free in suspension. In contrast to conventional culture systems, culture in the high aspect rotating-wall vessel facilitated the generation of multiple cell types that could be recovered. These results illustrate the ability of this culture system to provide the biological conditions necessary for pluripotent cell growth.