Fallopian tube precursors of ovarian low‐ and high‐grade serous neoplasms

Traditionally, it was thought that ovarian high‐grade serous carcinoma arises from the ovarian surface epithelium and epithelial inclusion glands and that the pathogenesis is de novo; nonetheless, a convincing precursor in the ovary or peritoneum has not been identified to date. During the last few years, however, there has been a dramatic shift in thinking, and a candidate precursor is now recognized in the fallopian tube, especially within the fimbriated end – serous tubal intra‐epithelial carcinoma (STIC). Accordingly, STIC is probably the earliest histologically recognizable lesion in the pathogenesis of high‐grade serous carcinoma, but steps in this pathway which precede STIC have also been proposed. With subsequent progression, STIC implants onto the ovary and then develops into an invasive high‐grade serous carcinoma with rapid tumour growth. For invasive low‐grade serous carcinoma, it is well‐established that its pathogenesis begins with serous cystadenoma/adenofibroma, which develops sequentially into atypical proliferative serous tumour (typical serous borderline tumour), non‐invasive micropapillary (low‐grade) serous carcinoma (micropapillary serous borderline tumour) and then invasive low‐grade serous carcinoma in a relatively slow stepwise process. It is presumed that cystadenoma/adenofibroma arises from epithelial inclusion glands in the ovary, but recent evidence suggests that epithelial inclusion glands originate in the fallopian tube. Alternatively, it has been proposed that the other early precursors in the low‐grade pathway, including serous borderline tumours, non‐invasive implants and endosalpingiosis, may also arise directly from tubal mucosa. Therefore, the precursor of most ovarian high‐grade serous carcinomas originates in the fallopian tube, and that for low‐grade serous tumours may also be derived from the tube. This review paper provides an overview of the fallopian tube's potential role in the pathogenesis of both types of serous neoplasms of the ovary.     

Recommendations for the reporting of fallopian tube neoplasms

Primary malignancies of the fallopian tube are extremely uncommon, in part due to (admittedly arbitrary) definitional criteria. By convention, epithelial tumors that involve the ovary or peritoneal surfaces are considered to have arisen either in the ovary or endometrium or, in absence of significant ovarian or endometrial involvement, in the peritoneum, irrespective of whether or not the fallopian tube mucosa is also involved. Evidence from the World Health Organization and more recently, from case-control studies of BRCA mutation carriers suggests the fallopian tube may have a more direct role in the development of at least some of these carcinomas. An alternative hypothesis for the origin of ovarian and peritoneal carcinoma has even been proposed, based on the concept of transport and implantation of malignant cells from the tube to the ovary and peritoneum. Malignancies in the fallopian tube can therefore be classified as (1) arising primarily in the fallopian tube, either from preexisting endometriosis (or more rarely, a mature teratoma) or directly from tubal mucosa with metastasis to adjacent tissues; (2) arising in the ovary, endometrium, or peritoneum with metastasis to the tubal serosa or mucosa; or (3) arising primarily in the fallopian tube as well as in the ovary, endometrium, or peritoneum (simultaneous primary tumors). Since there are currently no evidence based criteria for distinguishing primary tubal carcinoma from primary ovarian or primary endometrial carcinoma in patients with high stage disease, the Association of Directors of Anatomic and Surgical Pathology recommended strategies for assignment of site of origin are based on current standard practices.     

Mucosal carcinoma of the fallopian tube coexists with ovarian cancer of serous subtype only: a study of Japanese cases

Previous studies in Western countries have revealed that mucosal carcinoma of the fallopian tube frequently coexists with pelvic (ovarian, tubal, and peritoneal) serous carcinomas, and early tubal carcinoma is now regarded as a possible origin of these tumors. However, the relationship between early tubal carcinoma and non-serous ovarian cancer, such as clear cell adenocarcinoma, has not been studied in detail. In this study, we sought to examine the coexistence of mucosal carcinoma of the fallopian tube in Japanese ovarian cancer cases. We submitted the fallopian tubes in toto for histological examination in 52 ovarian carcinoma cases and three peritoneal serous carcinoma cases. The ovarian tumors included 12 serous adenocarcinomas, 23 clear cell adenocarcinomas, nine endometrioid adenocarcinomas, three mucinous adenocarcinomas, and four mixed epithelial carcinomas. Mucosal carcinoma of the fallopian tube did not coexist with non-serous adenocarcinoma (n = 40). In contrast, mucosal carcinoma of the fallopian tube was observed in six cases of ovarian serous adenocarcinoma and one case of peritoneal serous adenocarcinoma. In these cases, the p53 immunophenotypes were similar in tubal lesions and invasive ovarian or peritoneal carcinomas. Tumors were negative for p53 in four of seven cases, and one of the p53-negative serous adenocarcinomas showed low-grade morphology. We believe that some ovarian and peritoneal serous adenocarcinomas develop from early tubal carcinomas. However, it should be noted that early tubal carcinomas are not always p53-positive immunohistochemically. Finally, it is unlikely that early tubal lesions are involved in the carcinogenesis of clear cell adenocarcinoma and other non-serous adenocarcinomas.     

Cutaneous ciliated cyst: a case report and immunohistochemical comparison with fallopian tube

An example of a cutaneous ciliated cyst in the buttock of a 42 year old woman is reported. The histological and immunohistochemical features of the cyst are presented: comparisons with fallopian tube are made and this rare lesion is discussed.     

DNA profiling of primary serous ovarian and fallopian tube carcinomas with array comparative genomic hybridization and multiplex ligation-dependent probe amplification

Primary serous ovarian carcinoma (OVCA) and serous Fallopian tube carcinoma (FTC), both belonging to the BRCA-linked tumour spectrum, share many properties and are treated similarly. However, a detailed molecular comparison has been lacking. We hypothesized that comparative genomic studies of serous OVCAs and FTCs should point to gene regions critically involved in their tumorigenesis. Array comparative genomic hybridization (array CGH) analysis indicated that serous OVCAs and serous FTCs displayed common but also more distinctive patterns of recurrent changes. Targeted gene identification using a dedicated multiplex ligation-dependent probe amplification (MLPA) probe set directly identified EIF2C2 on 8q as a potentially important driver gene. Other previously unappreciated gained/amplified genes included PSMB4 on 1q, MTSS1 on 8q, TEAD4 and TSPAN9 on 12p, and BCAS4 on 20q. SPINT2 and ACTN4 on 19q were predominantly found in FTCs. Gains/amplifications of CCNE1 and MYC, often in conjunction with changes in genes of the AKT pathway, EVI1 and PTK2, seemed to be involved at earlier stages, whereas changes of ERBB2 were associated with advanced stages. The only BRCA1-mutated FTC shared common denominators with the sporadic tumours. In conclusion, the data suggest that serous OVCAs and FTCs, although related, exhibit differences in genomic profiles. In addition to known pathways, new genes/pathways are likely to be involved, with changes in an miRNA-associated gene, EIF2C2, as one important new feature. Dedicated MLPA sets constitute potentially important tools for differential diagnosis and may provide footholds for tailored therapy.     

An orthotopic model of platinum-sensitive high grade serous fallopian tube carcinoma

Fallopian tube carcinoma (FTCA) is a very rare cancer type, but may be a useful platform for investigating high grade serous tumors of the pelvis that originate from a serous tubal intraepithelial carcinoma (STIC) precursor. Metastatic tumors from a patient diagnosed with Stage IIIC high grade serous FTCA (P0) were transplanted via intraperitoneal (IP) injection into a small cohort of mice (passage, P1). Patient information was obtained from the medical record. Tumors were grown, harvested and re-implanted or archived through P3. The P3 cohort was treated with saline (n=8) or cisplatin, 5 mg/kg (n=8), weekly for 4 weeks. After sacrifice, tumors from each passage and treatment group were passaged further, frozen or paraffin embedded. The patient underwent optimal cytoreductive surgery for Stage IIIC high grade serous FTCA in the presence of a STIC. The FTCA, areas of STIC and normal appearing FT stained positive for p53, PAX8, pH2AX and mib-1. The patient remained in remission 9 months after platinum-based chemotherapy. IP tumor propagation was readily achieved up to P3 in the mice. Similar to the patient, orthotopic tumors were identified along peritoneal and mesenteric surfaces. Tumor histopathological and molecular features were confirmed and maintained through P3. The P3 cisplatin-treated mice had fewer tumor implants, higher levels of pH2AX and lower levels of mib-1 expression compared to controls. This orthotopic model of platinum sensitive high grade serous FTCA is a viable platform to study the biology and treatment of FTCA and other STIC-related pelvic serous carcinomas.     

Action and localization of neuropeptide Y in the human fallopian tube

Using indirect immunohistochemistry, neuropeptide Y-like immunoreactivity was found in nerve fibers around blood vessels and in the muscle layers of the human fallopian tube. Apart from a network of immunoreactive nerve fibers in connection with the luminary epithelium of the isthmus, the distribution resembled that of adrenergic, tyroxine hydroxylase immunoreactive, nerve fibers. Neuropeptide Y was found to have a dose-dependent inhibitory action on the adrenergic contractile response to field stimulation in the external longitudinal muscle layer of the isthmus. Furthermore, neuropeptide Y inhibited [3H]noradrenaline release from isthmic preparations during field stimulation, suggesting a prejunctional inhibitory action on adrenergic neurotransmission.     

A candidate precursor to serous carcinoma that originates in the distal fallopian tube

The tubal fimbria is a common site of origin for early (tubal intraepithelial carcinoma or TIC) serous carcinomas in women with familial BRCA1 or 2 mutations (BRCA+). Somatic p53 tumour suppressor gene mutations in these tumours suggest a pathogenesis involving DNA damage, p53 mutation, and progressive loss of cell cycle control. We recently identified foci of strong p53 immunostaining-termed 'p53 signatures'-in benign tubal mucosa from BRCA+ women. To examine the relationship between p53 signatures and TIC, we compared location (fimbria vs ampulla), cell type (ciliated vs secretory), evidence of DNA damage, and p53 mutation status between the two entities. p53 signatures were equally common in non-neoplastic tubes from BRCA+ women and controls, but more frequently present (53%) and multifocal (67%) in fallopian tubes also containing TIC. Like prior studies of TIC, p53 signatures predominated in the fimbriae (80-100%) and targeted secretory cells (HMFG2 + /p73-), with evidence of DNA damage by co-localization of gamma-H2AX. Laser-capture microdissected and polymerase chain reaction-amplified DNA revealed reproducible p53 mutations in eight of 14 fully-analysed p53 signatures and all of the 12 TICs; TICs and their associated ovarian carcinomas shared identical mutations. In one case, a contiguous p53 signature and TIC shared the same mutation. Morphological intermediates between the two, with p53 mutations and moderate proliferative activity, were also seen. This is the first report of an early and distinct alteration in non-neoplastic upper genital tract mucosa that fulfils many requirements for a precursor to pelvic serous cancer. The p53 signature and its malignant counterpart (TIC) underline the significance of the fimbria, both as a candidate site for serous carcinogenesis and as a target for future research on the early detection and prevention of this disease.     

Distribution of alpha glutathione S-transferase in ovarian neoplasms: an immunohistochemical study

AIMS: Alpha glutathione S-transferase (alpha-GST) has been shown to be an immunohistochemical marker for delta(4-5) isomerase, an enzyme active in steroidogenesis. The purpose of this study was to document the distribution of alpha-GST in ovarian neoplasms in order to evaluate its usefulness as a diagnostic tool. METHODS AND RESULTS: A total of 92 tumours (25 sex cord/stromal, 53 epithelial and 14 germ cell) were subjected to immunohistochemistry using a commercially available polyclonal antibody to alpha-GST. The avidin-biotin complex was used as a detection system. Positive staining was found in luteinized stromal cells of all tumour types (58/92). This included the Leydig cells of Sertoli-Leydig cell tumours (7/7) and was particularly prominent in the stromal cells of both benign and malignant mucinous tumours (24/25). Granulosa and Sertoli cells showed weak or no intracytoplasmic staining, which is expected because they do not normally produce androstenedione. They did show some intranuclear staining. Malignant mucinous (12/25) and occasional other epithelial tumours showed focal intracytoplasmic positive staining. Yolk sac tumours showed focal positivity (7/8). CONCLUSIONS: Intracytoplasmic staining of stromal cells is considered to indicate steroidogenesis and intranuclear staining the intracytoplasmic transport function of alpha-GST. The intracytoplasmic staining of mucinous carcinomas might represent an up-regulation of some detoxification function. The findings suggest that antibody to alpha-GST has some value in the investigation of ovarian pathology and could readily be included in any panel of antibodies used to investigate ovarian neoplasms of uncertain histogenesis.     

Fallopian tube origin of supposed ovarian high-grade serous carcinomas

INTRODUCTION:

Serous carcinomas are the most frequent histologic type of ovarian and peritoneal cancers, and can also be detected in the endometrium and fallopian tubes. Serous carcinomas are usually high‐grade neoplasms when diagnosed, yet the identification of an associated precursor lesion remains challenging. Pathological examination of specimens obtained from prophylactic bilateral salpingo‐oophorectomies that were performed for patients harboring BRCA1/2 mutations suggests that high‐grade serous carcinomas may arise in the fallopian tubes rather than in the ovaries.

OBJECTIVE:

To investigate the presence and extent of fallopian tube involvement in cases of serous pelvic carcinomas.

METHODS:

Thirty‐four cases of serous pelvic carcinoma with clinical presentations suggesting an ovarian origin were analyzed retrospectively. Histologic samples of fallopian tube tissues were available for these cases and were analyzed. Probable primary site, type of tubal involvement, tissues involved in the neoplasia and vascular involvement were evaluated.

RESULTS:

Fallopian tube involvement was observed in 24/34 (70.6%) cases. In 4 (11.8%) of these cases, an intraepithelial neoplasia was present, and therefore these cases were hypothesized to be primary from fallopian tubes. For an additional 7/34 (20.6%) cases, a fallopian tube origin was considered a possible primary.

CONCLUSIONS:

Fallopian tubes can be the primary site for a subset of pelvic high‐grade serous carcinomas.     

A genetically engineered ovarian cancer mouse model based on fallopian tube transformation mimics human high‐grade serous carcinoma development

Recent evidence suggests that ovarian high‐grade serous carcinoma (HGSC) originates from the epithelium of the fallopian tube. However, most mouse models are based on the previous prevailing view that ovarian cancer develops from the transformation of the ovarian surface epithelium. Here, we report the extensive histological and molecular characterization of the mogp–TAg transgenic mouse, which expresses the SV40 large T‐antigen (TAg) under the control of the mouse müllerian‐specific Ovgp‐1 promoter. Histological analysis of the fallopian tubes of mogp–TAg mice identified a variety of neoplastic lesions analogous to those described as precursors to ovarian HGSC. We identified areas of normal‐appearing p53‐positive epithelium that are similar to ‘p53 signatures’ in the human fallopian tube. More advanced proliferative lesions with nuclear atypia and epithelial stratification were also identified that were morphologically and immunohistochemically reminiscent of human serous tubal intraepithelial carcinoma (STIC), a potential precursor of ovarian HGSC. Beside these non‐invasive precursor lesions, we also identified invasive adenocarcinoma in the ovaries of 56% of the mice. Microarray analysis revealed several genes differentially expressed between the fallopian tube of mogp–TAg and wild‐type (WT) C57BL/6. One of these genes, Top2a, which encodes topoisomerase IIα, was shown by immunohistochemistry to be concurrently expressed with elevated p53 and was specifically elevated in mouse STICs but not in the surrounding tissues. TOP2A protein was also found elevated in human STICs, low‐grade and high‐grade serous carcinoma. The mouse model reported here displays a progression from normal tubal epithelium to invasive HGSC in the ovary, and therefore closely simulates the current emerging model of human ovarian HGSC pathogenesis. This mouse therefore has the potential to be a very useful new model for elucidating the mechanisms of serous ovarian tumourigenesis, as well as for developing novel approaches for the prevention, diagnosis and therapy of this disease. Published 2014. This article has been contributed to by US Government employees and their work is in the public domain in the USA.     

Immunohistochemical study of the expression of adhesion molecules in ovarian serous neoplasms

To clarify possible roles of adhesion molecules including E-cadherin, beta- and gamma-catenin, CD44s, CD44v6, CD56, and CD99 in ovarian serous neoplasms, an immunohistochemical study was undertaken for 23 benign, 40 borderline, and 95 malignant ovarian serous neoplasms using tissue microarray (TMA). Significantly reduced expression of E-cadherin, and overexpression of CD44s, CD56, and CD99 were more frequently observed in adenocarcinomas than in benign and borderline tumors. Expression of CD44v6 and nuclear beta- and gamma-catenin were detected only in borderline tumors and adenocarcinomas. Reduced expression of E-cadherin was also correlated with high tumor grade (P=0.03), presence of peritoneal seeding (P=0.03), and low overall survival rate (P=0.02). Overexpression of CD44s was significantly associated with high tumor grade (P=0.04), advanced stage (P=0.03), and low overall survival rate (P=0.02). CD56 was increasingly expressed in the case of advanced stage (P=0.005) and peritoneal seeding (P=0.001). Nuclear staining for gamma-catenin was correlated with tumor progression (P=0.004) and advanced International Federation of Gynecology and Obstetrics (FIGO) stage (P=0.02). Only CD44s expression and stage were correlated with overall survival in multivariate study. These results suggest that although E-cadherin, CD44s, CD56, and nuclear gamma-catenin immuno-expression seem to be useful prognostic markers for serous neoplasm of the ovary, CD44s expression and FIGO stage are independent prognostic factors.     

Morphometrical and immunohistochemical criteria of prognosis in patients with serous and mucinous ovarian carcinoma

The aim of the study was to investigate the prognostic value of morphometrical features and expression of receptors to progesterone in malignant epithelial ovarian tumours. Surgical biopsy materials of 92 patients with serous and mucinous ovarian cancer were investigated. Tissues stained by hematoxilin and eosin were studied. Morphometry was performed with computer program Axio Vision 3.0. Immunohistochemical characteristics were evaluated with monoclonal progesterone antibodies. It was found that cytomorphometrical features vary in ovarian cancer with different histological structures and the level of differentiation of tumour, and can be used as prognostic factors. We revealed correlation between cytomorphometric factors (carcinoma cell area, total nuclear area, roundness of cell) and risk of recurrences and metastatic spread. In serous cancers presence of progesterone receptors is a favorable factor of prognosis and, as a rule, associates with a high degree of tumour differentiation. In this group of patients 3-year survival reached almost 100% indicating the efficiency of hormonotherapy and chemotherapy.     

Key features of extrauterine pelvic serous tumours (fallopian tube, ovary, and peritoneum)

Key features of extrauterine pelvic serous tumours (fallopian tube, ovary, and peritoneum) Ovarian serous carcinoma (OSC) is the most common of the ovarian epithelial malignancies, and accounts for most of the mortality. Traditionally, ovarian cancer has been considered to be one disease; however, it is now apparent that it actually consists of many different entities. OSC can be further segregated into two processes: high-grade serous carcinoma (HGSC) and low-grade serous carcinoma. This classification is supported by molecular changes, morphological appearance, clinical behaviour, and distinct precursor lesions. This review will describe in detail these features of OSC, differential diagnosis, prognosis, and recent challenges to the existing hypotheses regarding the origin of these tumours. Special attention will be paid to HGSC and its relationship with BRCA abnormalities, especially those seen in hereditary breast and ovarian cancer syndrome. Finally, treatment options based on specific molecular targets will be discussed.