Serous carcinogenesis in the fallopian tube: a descriptive classification

The challenge of managing isolated STIC lesions: A single-center experience

Objectives

High-grade serous carcinoma (HGSC) arise from serous tubal intraepithelial carcinoma (STIC) lesions, a precursor that develops from the fallopian tube epithelium. Patients with incidental isolated STIC lesions found on salpingectomy specimen have up to 25% risk of developing HGSC or peritoneal carcinomatosis in the future, yet there is no established consensus to guide management.

Methods

This retrospective case series includes patients diagnosed with isolated STIC lesions between April 2017 and January 2024. Patient data was extracted from clinical and pathological databases.

Results

During the study period, 10 patients were diagnosed with an isolated STIC lesion. The fallopian tubes were removed either as part of a hysterectomy for endometrial cancer (n = 3); a prophylactic risk-reducing surgery for BRCA1 or BRCA2 mutation (n = 3); or a benign gynecologic condition (n = 4). The median age of the patients was 64 years (range: 53-80). Among patients who underwent genetic testing (n = 9), only three were found to have a deleterious germline mutation in BRCA1 or BRCA2. The patients either received adjuvant chemotherapy (n = 5) or underwent active surveillance (n = 5). One surveillance patient was managed with completion bilateral oophorectomy and omentectomy. Median number of chemotherapy cycles was four (range 4-6 cycles). The median follow-up was 27 months (range: 5-83 months). One patient under active surveillance was diagnosed with peritoneal carcinomatosis 5 years after initial diagnosis of STIC whereas none recurred in the chemotherapy group.

Conclusion

The wide variety of treatment approaches we observed highlights a need for more data on this entity to support management guidelines.

Controversies in the management of serous tubal intra-epithelial carcinoma lesions of the fallopian tube

High-grade serous carcinoma is the most lethal gynecological malignancy. Although serous tubal intra-epithelial carcinoma is increasingly recognized as a precursor to high-grade serous carcinoma, its optimal management remains controversial. This review examines the controversies in serous tubal intra-epithelial carcinoma pathogenesis, diagnosis, management, and follow-up, highlighting the need for collaboration, standardized guidelines, and further research to improve patient outcomes.

Primarian fallopian tube carcinoma: Clinical and radiological keys for diagnosis

Primary fallopian tube carcinoma (PFTC) is seldom diagnosed preoperatively and is often mistaken for epithelial ovarian carcinoma (EOC). This report details a case of primary high-grade serous carcinoma (HGSC) of the fallopian tube, highlighting radiological and clinical indicators to aid in accurate diagnosis and avoid misdiagnosis. A 46-year-old premenopausal woman presented with symptoms and a transvaginal ultrasound (TVUS) indicating a malignant ovarian tumor. Further imaging with CT and MRI revealed a solid-cystic mass suggestive of a fallopian tube tumor rather than an ovarian origin. Oncological surgery confirmed the presence of a high-grade serous carcinoma in the fallopian tube. This case underscores the diagnostic challenges of PFTC and the superior sensitivity and specificity of MRI over CT and US in distinguishing adnexal lesions. Key MRI features such as the sausage-shaped mass and associated hematosalpinx were crucial in differentiating PFTC from EOC. The report emphasizes the importance of considering PFTC in differential diagnoses of adnexal masses to ensure accurate preoperative identification.

Biology-driven therapy advances in high-grade serous ovarian cancer

Following a period of slow progress, the completion of genome sequencing and the paradigm shift relative to the cell of origin for high grade serous ovarian cancer (HGSOC) led to a new perspective on the biology and therapeutic solutions for this deadly cancer. Experimental models were revisited to address old questions, and improved tools were generated. Additional pathways emerging as drivers of ovarian tumorigenesis and key dependencies for therapeutic targeting, in particular, VEGF-driven angiogenesis and homologous recombination deficiency, were discovered. Molecular profiling of histological subtypes of ovarian cancer defined distinct genetic events for each entity, enabling the first attempts toward personalized treatment. Armed with this knowledge, HGSOC treatment was revised to include new agents. Among them, PARP inhibitors (PARPis) were shown to induce unprecedented improvement in clinical benefit for selected subsets of patients. Research on mechanisms of resistance to PARPis is beginning to discover vulnerabilities and point to new treatment possibilities. This Review highlights these advances, the remaining challenges, and unsolved problems in the field.

Ovarian Cancer: From Precursor Lesion Identification to Population-Based Prevention Programs

Epithelial ovarian cancer (EOC) is a heterogeneous group of malignancies, including high-grade serous ovarian cancer (HGSC). HGSC is often diagnosed at advanced stages and is linked to TP53 variants. While BRCA variants elevate risk, most HGSC cases occur in individuals without known genetic variants, necessitating prevention strategies for people without known high-risk genetic variants. Effective prevention programs are also needed due to the lack of traditional screening options. An emerging primary prevention strategy is opportunistic salpingectomy, which involves removing fallopian tubes during another planned pelvic surgery. Opportunistic salpingectomy offers a safe and cost-effective preventative option that is gaining global adoption. With the publication of the first cohort study of patients who underwent salpingectomy, specifically for cancer prevention, attention has turned to broadening opportunities for salpingectomy in addition to more targeted approaches. Prevention opportunities are promising with increasing adoption of salpingectomy and the increased understanding of the etiology of the distinct histotypes of ovarian cancer. Yet, further research on targeted risk-reducing salpingectomy with thoughtful consideration of equity is necessary to reduce death and suffering from ovarian cancer.

Reevaluating the Role of Progesterone in Ovarian Cancer: Is Progesterone Always Protective?

Ovarian cancer (OC) represents a collection of rare but lethal gynecologic cancers where the difficulty of early detection due to an often-subtle range of abdominal symptoms contributes to high fatality rates. With the exception of BRCA1/2 mutation carriers, OC most often manifests as a post-menopausal disease, a time in which the ovaries regress and circulating reproductive hormones diminish. Progesterone is thought to be a "protective" hormone that counters the proliferative actions of estrogen, as can be observed in the uterus or breast. Like other steroid hormone receptor family members, the transcriptional activity of the nuclear progesterone receptor (nPR) may be ligand dependent or independent and is fully integrated with other ubiquitous cell signaling pathways often altered in cancers. Emerging evidence in OC models challenges the singular protective role of progesterone/nPR. Herein, we integrate the historical perspective of progesterone on OC development and progression with exciting new research findings and critical interpretations to help paint a broader picture of the role of progesterone and nPR signaling in OC. We hope to alleviate some of the controversy around the role of progesterone and give insight into the importance of nPR actions in disease progression. A new perspective on the role of progesterone and nPR signaling integration will raise awareness to the complexity of nPRs and nPR-driven gene regulation in OC, help to reveal novel biomarkers, and lend critical knowledge for the development of better therapeutic strategies.

A Clinical and Immunopathological Analysis of Carcinoma of the Ovary with an Emphasis on Post-chemotherapy Histopathologic Changes

Ovarian cancers are a heterogeneous group of malignant tumors that differ with respect to pathogenesis, morphology, molecular features, and behavior. Pathologists and clinicians need to be aware of the advances in diagnosis and the changes which occur after chemotherapy to offer the optimal treatment to each patient. The present work aims to study the morphologic and immunohistochemical (IHC) profile of primary ovarian cancers with an assessment of post-chemotherapy changes. A total of 51 cases were included in the study from June 2017 to June 2019 (prospective and retrospective). The demographic and clinical details of the patients were collected. The gross and microscopic features of the tumors were studied, and the post-chemotherapy changes were evaluated. A chi-square test was used to determine the association of tumor morphology, the chemotherapy response score (CRS), and stage of the tumor with survival (PFS and OS). The mean patient age was 47.5 years, and high-grade serous carcinoma (66.6%) (HGSC) was the most common subtype followed by mucinous carcinoma and endometrioid carcinoma. Immunohistochemical analysis with WT1 and p53 helped in the diagnosis of HGSC. The CRS was 1 and 2 in most of the cases. The follow-up for patients of HGSC was available for a period of 1-27 months with a mean survival for primary resection of 24 months and for post-NACT resection was 17 months. This difference was not statistically significant (p = 0.38). High-grade serous carcinoma was the most common ovarian cancer in our series, and immunohistochemistry played an important role in the diagnosis. We could not demonstrate any survival benefit of preoperative chemotherapy in our series.

Expression and T cell regulatory action of the PD-1 immune checkpoint in the ovary and fallopian tube

PROBLEM

Immune cell trafficking and surveillance within the ovary and fallopian tube are thought to impact fertility and also tumorigenesis in those organs. However, little is known of how native cells of the ovary and fallopian tube interact with resident immune cells. Interaction of the Programmed Cell Death Protein-1 (PD-1/PDCD-1/CD279) checkpoint with PD-L1 is associated with downregulated immune response. We have begun to address the question of whether PD-1 ligand or its receptors (PD-L1/-L2) can regulate immune cell function in these tissues of the female reproductive tract.

METHOD OF STUDY

PD-1 and ligand protein expression was evaluated in human ovary and fallopian tube specimens, the latter of which included stages of tubal cell transformation and early tumorigenesis. Ovarian expression analysis included the determination of the proteins in human follicular fluid (HFF) specimens collected during in vitro fertilization procedures. Finally, checkpoint bioactivity of HFF was determined by treatment of separately-isolated human T cells and the measurement of interferon gamma (IFNγ).

RESULTS

We show that membrane bound and soluble variants of PD-1 and ligands are expressed by permanent constituent cell types of the human ovary and fallopian tube, including granulosa cells and oocytes. PD-1 and soluble ligands were present in HFF at bioactive levels that control T cell PD-1 activation and IFNγ production; full-length checkpoint proteins were found to be highly enriched in HFF exosome fractions.

CONCLUSION

The detection of PD-1 checkpoint proteins in the human ovary and fallopian tube suggests that the pathway is involved in immunomodulation during folliculogenesis, the window of ovulation, and subsequent egg and embryo immune-privilege. Immunomodulatory action of receptor and ligands in HFF exosomes is suggestive of an acute checkpoint role during ovulation. This is the first study in the role of PD-1 checkpoint proteins in human tubo-ovarian specimens and the first examination of its potential regulatory action in the contexts of normal and assisted reproduction.

[Morphological precursors of high-grade serous ovarian cancer]

At the beginning of this century, there was a paradigm shift in understanding the histogenesis of high-grade serous carcinomas. The theory of the origin of these tumors from the ovarian surface epithelium was replaced by the concept of their origin from the secretory epithelium of the fallopian tubes. In recent years, researchers have put forward the hypothesis of the "escape" of the precursor of high-grade serous carcinomas. It allows looking at the carcinogenesis of these neoplasms as a natural history of tumor transformation of the serous epithelium without reference to a specific localization.

Serous Tubal Intraepithelial Carcinoma in a Risk-reducing Salpingo-oophorectomy Specimen From a RAD51D Mutation Carrier: A Case Report

The RAD51D gene codes a protein-paralog of the RAD51 DNA recombinase, which catalyzes DNA strand exchange during homologous recombination. Similar to BRCA1 / BRCA2 , mutations in RAD51D both predispose to ovarian carcinoma and impart sensitivity to poly (ADP-ribose) polymerase inhibitors in preclinical studies. Based on cancer risk prediction models, RAD51D mutations pose a moderate-to-high risk for ovarian cancer warranting consideration for risk-reducing surgery. We report a case of serous tubal intraepithelial carcinoma in a patient undergoing risk-reducing total hysterectomy with bilateral salpingo-oophorectomy for a RAD51D pathogenic variant. The histopathologic and p53-immunophenotypic features of this lesion are similar to those reported previously in BRCA1 / BRCA2 mutation carriers and those of serous tubal intraepithelial carcinoma associated with sporadic high-grade serous carcinomas. These features include marked increase in nuclear-to-cytoplasmic ratio, loss of cell polarity, absence of ciliation, prominent nucleoli, mitotic activity, epithelial stratification, surface exfoliative changes, and complete loss of p53 staining. Although familial ovarian cancers with mutations in RAD51D -or other genes in the Fanconi anemia pathway-are much less common those with BRCA1 / BRCA2 mutations, our findings support a common phenotype for early serous cancers in this pathway.

Pathologic Findings at Risk Reducing Surgery in BRCA and Non-BRCA Mutation Carriers: A Single-Center Experience

Risk-reducing surgery (RRS) is recommended in BRCA-mutated carriers because of their increased risk of developing ovarian cancer, while its role is still discussed for women harboring mutations in non-BRCA homologous repair genes. The aim of this study was to retrospectively evaluate the occurrence of pathological findings in a high-risk population undergoing RRS in San Matteo Hospital, Pavia between 2012 and 2022, and correlate their genetic and clinical outcomes, comparing them with a control group. The final cohort of 190 patients included 85 BRCA1, 63 BRCA2, 11 CHEK2, 7 PALB2, 4 ATM, 1 ERCC5, 1 RAD51C, 1 CDH1, 1 MEN1, 1 MLH1 gene mutation carriers and 15 patients with no known mutation but with strong familial risk. Occult invasive serous carcinoma (HGSC) and serous tubal intraepithelial carcinoma (STIC) were diagnosed in 12 (6.3%) women, all of them BRCA carriers. No neoplastic lesion was diagnosed in the non-BRCA group, in women with familial risk, or in the control group. Oral contraceptive use and age ≤45 at surgery were both found to be favorable factors. While p53 signature and serous tubal intraepithelial lesion (STIL) were also seen in the control group and in non-BRCA carriers, STIC and HGSC were only found in BRCA1/2 mutation carriers.

Molecular Management of High-Grade Serous Ovarian Carcinoma

High-grade serous ovarian carcinoma (HGSOC) represents the most common form of epithelial ovarian carcinoma. The absence of specific symptoms leads to late-stage diagnosis, making HGSOC one of the gynecological cancers with the worst prognosis. The cellular origin of HGSOC and the role of reproductive hormones, genetic traits (such as alterations in P53 and DNA-repair mechanisms), chromosomal instability, or dysregulation of crucial signaling pathways have been considered when evaluating prognosis and response to therapy in HGSOC patients. However, the detection of HGSOC is still based on traditional methods such as carbohydrate antigen 125 (CA125) detection and ultrasound, and the combined use of these methods has yet to support significant reductions in overall mortality rates. The current paradigm for HGSOC management has moved towards early diagnosis via the non-invasive detection of molecular markers through liquid biopsies. This review presents an integrated view of the relevant cellular and molecular aspects involved in the etiopathogenesis of HGSOC and brings together studies that consider new horizons for the possible early detection of this gynecological cancer.

Serous tubal intraepithelial carcinoma: What Do We Really Know at this Point?

Serous tubal intraepithelial carcinoma (STIC) is the earliest morphologically recognizable step in the development of invasive high-grade serous carcinoma of the fallopian tube. Lesions occurring prior to STIC within the carcinogenic sequence for the pathogenesis of invasive high-grade serous carcinoma include the p53 signature and secretory cell outgrowth (SCOUT). Variable histologic criteria have been used for diagnosing STIC, but a combination of morphology and immunohistochemistry for p53/Ki-67 improves interobserver agreement. Half of all carcinomas identified in risk-reducing salpingo-oophorectomy specimens are in the form of STIC; however, STIC also may be incidentally found on occasion in specimens from women at low or average risk of ovarian/tubal/peritoneal carcinoma. TP53 mutation is the earliest known DNA sequence alteration in STIC and almost all invasive high-grade serous carcinomas of the ovary and peritoneum. Data on the clinical behavior of STIC are limited. While the short-term follow-up in the prior literature suggests a low risk of malignant progression, a more recent meta-analysis indicates a 10-year risk of 28%. STIC probably should be best regarded as a lesion with uncertain malignant potential at present, and future molecular analysis will help classify those with higher risk of dissemination. This review article provides an update on the current knowledge of STIC and related issues.

Phosphate dysregulation via the XPR1-KIDINS220 protein complex is a therapeutic vulnerability in ovarian cancer

Despite advances in precision medicine, the clinical prospects for patients with ovarian and uterine cancers have not substantially improved. Here, we analyzed genome-scale CRISPR/Cas9 loss-of-function screens across 851 human cancer cell lines and found that frequent overexpression of SLC34A2 – encoding a phosphate importer – is correlated to sensitivity to loss of the phosphate exporter XPR1 in vitro and in vivo. In patient-derived tumor samples, we observed frequent PAX8-dependent overexpression of SLC34A2, XPR1 copy number amplifications, and XPR1 mRNA overexpression. Mechanistically, in SLC34A2-high cancer cell lines, genetic or pharmacologic inhibition of XPR1-dependent phosphate efflux leads to the toxic accumulation of intracellular phosphate. Finally, we show that XPR1 requires the novel partner protein KIDINS220 for proper cellular localization and activity, and that disruption of this protein complex results in acidic vacuolar structures preceding cell death. These data point to the XPR1:KIDINS220 complex and phosphate dysregulation as a therapeutic vulnerability in ovarian cancer.

Golub and colleagues identify the phosphate exporter XPR1 as a therapeutic vulnerability in ovarian and uterine cancers, and show that phosphate efflux inhibition reduces tumor cell viability through accumulation of intracellular phosphate.

The Many Faces of Serous Neoplasms and Related Lesions of the Female Pelvis: A Review

Ovarian serous tumors and related lesions are one of the most common conditions of the female genital tract. While ovarian high-grade serous carcinoma carries high mortality and adverse prognosis, most other serous lesions have better clinical behavior. In recent years, significant progress has been made in understanding the nature and histogenesis of these lesions that has contributed to better and more precise clinical management. Most of the high-grade serous carcinomas involve the ovaries and/or peritoneum, although in most cases, their origin seems to be in the fallopian tube. This view is supported by the recognition of precursor lesions in the fallopian tube, such as p53 signature and serous tubular in situ carcinoma. This paper presents salient morphologic, immunohistochemical, and molecular data related to serous tumors and related lesions of the female pelvis and discusses the histogenetic interrelationship among these lesions in light of current knowledge.

Racial and ethnic differences in the adoption of opportunistic salpingectomy for ovarian cancer prevention in the United States

BACKGROUND

Clinicians in the United States have rapidly adopted opportunistic salpingectomy for ovarian cancer prevention. However, little is known about racial and ethnic differences in opportunistic salpingectomy adoption. Surgical innovations in gynecology may be adopted differentially across racial and ethnic groups, exacerbating current disparities in quality of care.

OBJECTIVE

This study aimed to evaluate racial and ethnic differences in opportunistic salpingectomy adoption across inpatient and outpatient settings and assess the effect of national guidelines supporting opportunistic salpingectomy use on these differences.

STUDY DESIGN

A sample of 650,905 women aged 18 to 50 years undergoing hysterectomy with ovarian conservation or surgical sterilization from 2011 to 2018 was identified using the Premier Healthcare Database, an all-payer hospital administrative database, including more than 700 hospitals across the United States. The association between race and ethnicity and opportunistic salpingectomy use was examined using multivariable-adjusted mixed-effects log-binomial regression models accounting for hospital-level clustering. Models included race and ethnicity by year of surgery (2011-2013 [before guideline] and 2014-2018 [after guideline]) interaction term to test whether racial and ethnic differences in opportunistic salpingectomy adoption changed with the release of national guidelines supporting opportunistic salpingectomy use.

RESULTS

From 2011 to 2018, 82,792 women underwent hysterectomy and opportunistic salpingectomy (non-Hispanic White, 60.3%; non-Hispanic Black, 18.8%; Hispanic, 12.2%; non-Hispanic other race, 8.7%) and 23,398 women underwent opportunistic salpingectomy for sterilization (non-Hispanic White, 64.7%; non-Hispanic Black, 10.8%; Hispanic, 16.7%; non-Hispanic other race, 7.8%). The proportion of hysterectomy procedures involving an opportunistic salpingectomy increased from 6.3% in 2011 to 59.7% in 2018 (9.5-fold increase), and the proportion of sterilization procedures involving an opportunistic salpingectomy increased from 0.7% in 2011 to 19.4% in 2018 (27.7-fold increase). In multivariable-adjusted models, non-Hispanic Black (risk ratio, 0.94; 95% confidence interval, 0.92-0.97), Hispanic (risk ratio, 0.98; 95% confidence interval, 0.95-1.00), and non-Hispanic other race women (risk ratio, 0.93; 95% confidence interval, 0.90-0.96) were less likely to undergo hysterectomy and opportunistic salpingectomy than non-Hispanic White women. A significant interaction between race and ethnicity and year of surgery was noted in non-Hispanic Black compared with non-Hispanic White women (P<.001), with a reduction in differences in hysterectomy and opportunistic salpingectomy use after national guideline release (risk ratio_2011-2013, 0.80 [95% confidence interval, 0.73-0.88]; risk ratio_2014-2018, 0.98 [95% confidence interval, 0.95-1.01]). Moreover, non-Hispanic Black women were less likely to undergo an opportunistic salpingectomy for sterilization than non-Hispanic White women (risk ratio, 0.91; 95% confidence interval, 0.88-0.95), with no difference by year of surgery (P=.62). Stratified analyses by hysterectomy route and age at surgery revealed similar results.

CONCLUSION

Although opportunistic salpingectomy for ovarian cancer prevention has been rapidly adopted in the United States, our findings suggested that its adoption has not been equitable across racial and ethnic groups. Non-Hispanic Black, Hispanic, and non-Hispanic other race women were less likely to undergo opportunistic salpingectomy than non-Hispanic White women even after adjusting for sociodemographic, clinical, procedural, hospital, and provider characteristics. These differences persisted after the release of national guidelines supporting opportunistic salpingectomy use. Future research should focus on understanding the reasons for these differences to inform interventions that promote equity in opportunistic salpingectomy use.

The Transcoelomic Ecosystem and Epithelial Ovarian Cancer Dissemination

Epithelial ovarian cancer (EOC) is considered the deadliest gynecological disease and is normally diagnosed at late stages, at which point metastasis has already occurred. Throughout disease progression, EOC will encounter various ecosystems and the communication between cancer cells and these microenvironments will promote the survival and dissemination of EOC. The primary tumor is thought to develop within the ovaries or the fallopian tubes, both of which provide a microenvironment with high risk of causing DNA damage and enhanced proliferation. EOC disseminates by direct extension from the primary tumors, as single cells or multicellular aggregates. Under the influence of cellular and non-cellular factors, EOC spheroids use the natural flow of peritoneal fluid to reach distant organs within the peritoneal cavity. These cells can then implant and seed distant organs or tissues, which develop rapidly into secondary tumor nodules. The peritoneal tissue and the omentum are two common sites of EOC metastasis, providing a microenvironment that supports EOC invasion and survival. Current treatment for EOC involves debulking surgery followed by platinum-taxane combination chemotherapy; however, most patients will relapse with a chemoresistant disease with tumors developed within the peritoneum. Therefore, understanding the role of the unique microenvironments that promote EOC transcoelomic dissemination is important in improving patient outcomes from this disease. In this review article, we address the process of ovarian cancer cellular fate at the site of its origin in the secretory cells of the fallopian tube or in the ovarian surface epithelial cells, their detachment process, how the cells survive in the peritoneal fluid avoiding cell death triggers, and how cancer- associated cells help them in the process. Finally, we report the mechanisms used by the ovarian cancer cells to adhere and migrate through the mesothelial monolayer lining the peritoneum. We also discuss the involvement of the transcoelomic ecosystem on the development of chemoresistance of EOC.

Models for measuring metabolic chemical changes in the metastasis of high grade serous ovarian cancer: fallopian tube, ovary, and omentum

Ovarian cancer (OC) is the most lethal gynecologic malignancy and high grade serous ovarian cancer (HGSOC) is the most common and deadly subtype, accounting for 70-80% of OC deaths. HGSOC has a distinct pattern of metastasis as many believe it originates in the fallopian tube and then it metastasizes first to the ovary, and later to the adipose-rich omentum. Metabolomics has been heavily utilized to investigate metabolite changes in HGSOC tumors and metastasis. Generally, metabolomics studies have traditionally been applied to biospecimens from patients or animal models; a number of recent studies have combined metabolomics with innovative cell-culture techniques to model the HGSOC metastatic microenvironment for the investigation of cell-to-cell communication. The purpose of this review is to serve as a tool for researchers aiming to model the metastasis of HGSOC for metabolomics analyses. It will provide a comprehensive overview of current knowledge on the origin and pattern of metastasis of HGSOC and discuss the advantages and limitations of different model systems to help investigators choose the best model for their research goals, with a special emphasis on compatibility with different metabolomics modalities. It will also examine what is presently known about the role of small molecules in the origin and metastasis of HGSOC.

Uptake and Predictors of Opportunistic Salpingectomy for Ovarian Cancer Risk Reduction in the United States

Evidence suggesting that high-grade serous ovarian cancers originate in the fallopian tubes has led to the emergence of opportunistic salpingectomy (OS) as an approach to reduce ovarian-cancer risk. In the U.S., some national societies now recommend OS in place of tubal ligation for sterilization or during a benign hysterectomy in average-risk women. However, limited data exist on the dissemination of OS in clinical practice. We examined the uptake and predictors of OS in a nationwide sample of inpatient and outpatient claims (N = 48,231,235) from 2010 to 2017. Incidence rates of OS were calculated, and an interrupted time-series analysis was used to quantify changes in rates before (2010-2013) and after (2015-2017) national guideline release. Predictors of OS use were examined using Poisson regression. From 2010 to 2017, the age-adjusted incidence rate of OS for sterilization and OS during hysterectomy increased 17.8-fold [95% confidence interval (CI), 16.2-19.5] and 7.6-fold (95% CI, 5.5-10.4), respectively. The rapid increase (age-adjusted increase in quarterly rates of between 109% and 250%) coincided with the time of national guideline release. In multivariable-adjusted analyses, OS use was more common in young women and varied significantly by geographic region, rurality, family history/genetic susceptibility, surgical indication, inpatient/outpatient setting, and underlying comorbidities. Similar differences in OS uptake were noted in analyses limited to women with a family history/genetic susceptibility to breast/ovarian cancer. Our results highlight significant differences in OS uptake in both high- and average-risk women. Defining subsets of women who would benefit most from OS and identifying barriers to equitable OS uptake is needed. PREVENTION RELEVANCE: Opportunistic salpingectomy for ovarian-cancer risk reduction has been rapidly adopted in the U.S., with significant variation in uptake by demographic and clinical factors. Studies examining barriers to opportunistic salpingectomy access and the long-term effectiveness and potential adverse effects of opportunistic salpingectomy are needed.

What Is New on Ovarian Carcinoma: Integrated Morphologic and Molecular Analysis Following the New 2020 World Health Organization Classification of Female Genital Tumors

Ovarian carcinomas represent a heterogeneous group of neoplasms consisting of separate entities with distinct risk factors, precursor lesions, pathogenesis, patterns of spread, molecular profiles, clinical course, response to chemotherapy, and outcomes. The histologic subtype and the related molecular features are essential for individualized clinical decision-making. The fifth edition of the World Health Organization classification of tumors of the female genital tract divides ovarian carcinomas into at least five main and distinct types of ovarian carcinomas: high-grade serous carcinoma, low-grade serous carcinoma, endometrioid carcinoma, clear cell carcinoma, and mucinous carcinoma. Molecular pathology has improved the knowledge of genomic landscape of ovarian carcinomas identifying peculiar alterations for every histologic subtype. It is well-known that high-grade and low-grade serous carcinomas are separate entities with entirely different morphologic and molecular characteristics. TP53 and BRCA mutations are typical of high-grade serous carcinoma, whereas BRAF and KRAS mutations frequently occur in low-grade serous carcinoma. Endometrioid and clear cell carcinomas are frequently associated with endometriosis. Endometrioid tumors are characterized by β-catenin alterations, microsatellite instability, and PTEN and POLE mutations, while ARID1A mutations occur in both endometrioid and clear cell carcinomas. Mucinous carcinomas are uncommon tumors associated with copy-number loss of CDKN2A and KRAS alterations and metastasis from other sites should always be considered in the differential diagnosis.

Value of adjuvant chemotherapy and informed microscopic examination for occult gynecologic cancer detected upon risk-reducing salpingo-oophorectomy after chemotherapy for BRCA1/2-associated breast cancer: a case report

BRCA1/2 mutation carriers are at high risk for type II ovarian, fallopian tube or peritoneal cancer. Although risk-reducing salpingo-oophorectomy plays an important role in the prevention of these BRCA1/2-associated gynecological cancers, occult ovarian, fallopian tube, or peritoneal cancer is discovered upon risk-reducing salpingo-oophorectomy in 1-4% of BRCA1/2 mutation carriers. Notably, around 30% of BRCA1/2 mutation carriers who undergo risk-reducing salpingo-oophorectomy have undergone adjuvant chemotherapy for breast cancer. We describe the discovery and treatment of occult cancer at the edge of the left fimbria in a BRCA1 mutation carrier who had, just a short time previously, undergone neoadjuvant paclitaxel plus carboplatin (TC) chemotherapy for triple-negative breast cancer. During subsequent risk-reducing salpingo-oophorectomy, a 5.5-mm nodule was observed at the edge of the left fimbria. Microscopic examination of the tumour tissue revealed high-grade serous carcinoma with degenerate tumour cells and fibrosis. Peritoneal fluid was negative for cancer cells. Two months later, hysterectomy, omentectomy and retroperitoneal lymphadenectomy were performed. The final diagnosis was stage FIGO IA fallopian tube cancer. Adjuvant chemotherapy (TC administered every 3 weeks) was applied, and there has been no evidence of recurrence for 5 years. In applying gynecologic surgery and adjuvant chemotherapy, we followed the general recommendation for stage IA fallopian tube cancer. There is no standard strategy for the treatment of occult fallopian tube cancer detected after chemotherapy for BRCA1-associated triple-negative breast cancer. According to our experience in this case, we believe the clinical value of staging laparotomy in cases of a small occult BRCA1/2-associated gynecological cancer should be further investigated.

Recent Advances in Integrative Multi-Omics Research in Breast and Ovarian Cancer

The underlying molecular heterogeneity of cancer is responsible for the dynamic clinical landscape of this disease. The combination of genomic and proteomic alterations, including both inherited and acquired mutations, promotes tumor diversity and accounts for variable disease progression, therapeutic response, and clinical outcome. Recent advances in high-throughput proteogenomic profiling of tumor samples have resulted in the identification of novel oncogenic drivers, tumor suppressors, and signaling networks; biomarkers for the prediction of drug sensitivity and disease progression; and have contributed to the development of novel and more effective treatment strategies. In this review, we will focus on the impact of historical and recent advances in single platform and integrative proteogenomic studies in breast and ovarian cancer, which constitute two of the most lethal forms of cancer for women, and discuss the molecular similarities of these diseases, the impact of these findings on our understanding of tumor biology as well as the clinical applicability of these discoveries.

Ovulatory Follicular Fluid Facilitates the Full Transformation Process for the Development of High-Grade Serous Carcinoma

Background: High-grade serous carcinoma (HGSC) is mainly derived from the stepwise accumulation of driver mutations in the fallopian tube epithelium (FTE), and it subsequently metastasizes to the ovary and peritoneum that develops into a clinically evident ovarian carcinoma. The developmental process involves cell proliferation/clonal expansion, cell migration, anoikis resistance, anchorage-independent growth (AIG), peritoneum attachment, and cell invasion. Previously, we discovered FTE could be transformed by follicular fluid (FF) released from ovulation, the most crucial risk factor of ovarian cancer, and IGF axis proteins in FF confers stemness activation and clonal expansion via IGF-1R/AKT pathway. However, whether other phenotypes in advanced cancer development are involved is unknown. Methods: A panel of FTE and ovarian HGSC cell lines with different severity of transformation were treated with FF with or without IGF-1R and AKT inhibitors and analyzed for the transformation phenotypes in vitro, ex vivo, and in vivo. Results: FF largely promotes (by order of magnitude) cell migration, AIG, cell invasion, peritoneum attachment, anoikis resistance, and cell proliferation. Most of these activities worked in the full panel of cell lines. The AIG activity largely depends on IGF-1R/AKT phosphorylation, and the proliferation activity depends on an AKT phosphorylation not mediated by IGF-1R. In contrast, both AKT- and non-AKT-mediated signals are responsible for the other transformation activities. Conclusions: Our data demonstrate an extensive transformation activity of FF in the full journey of carcinogenesis, and endorsed ovulation-inhibition for the prevention and AKT-inhibition for the treatment of ovarian HGSC.

PAX8, an Emerging Player in Ovarian Cancer

Ovarian Cancer is one of the most lethal and widespread gynecological malignancies. It is the seventh leading cause of all cancer deaths worldwide. High-Grade Serous Cancer (HGSC), the most commonly occurring subtype, alone contributes to 70% of all ovarian cancer deaths. This is mainly attributed to the complete lack of symptoms during the early stages of the disease and absence of an early diagnostic marker.PAX8 is emerging as an important histological marker for most of the epithelial ovarian cancers, as it is expressed in about 90% of malignant ovarian cancers, specifically in HGSC. PAX8 is a member of the Paired-Box gene family (PAX1-9) of transcription factors whose expression is tightly controlled temporally and spatially. The PAX genes are well known for their role in embryonic development and their expression continues to persist in some adult tissues. PAX8 is required for the normal development of Müllerian duct that includes Fallopian tube, uterus, cervix, and upper part of vagina. In adults, it is expressed in the Fallopian tube and uterine epithelium and not in the ovarian epithelium. Considering the recent studies that predict the events preceding the tumorigenesis of HGSC from the Fallopian tube, PAX8 appears to have an important role in the development of ovarian cancer.In this chapter, we review some of the published findings to highlight the significance of PAX8 as an important marker and an emerging player in the pathogenesis of ovarian cancer. We also discuss regarding the future perspectives of PAX8 wherein it could contribute to the betterment of ovarian cancer diagnosis and treatment.

Multimodality Imaging Approach to Ovarian Neoplasms with Pathologic Correlation

Ovarian neoplasms can be categorized on the basis of histopathologic features into epithelial surface cell tumors, germ cell tumors, sex cord-stromal tumors, and metastases. While their imaging appearance is often nonspecific, it closely parallels the gross pathologic appearance, and radiologic-pathologic correlation is helpful to aid in a deeper understanding of the subtypes. Epithelial cell neoplasms are the most common category, and they can be benign, borderline, or malignant. Specific subtypes include serous (most common), mucinous, seromucinous, endometrioid, clear cell, Brenner, and undifferentiated. High-grade serous cystadenocarcinoma accounts for the majority of malignant ovarian tumors and the most ovarian cancer deaths. While serous neoplasms are often unilocular and bilateral, mucinous neoplasms are larger, unilateral, and multilocular. Solid components, thickened septa, and papillary projections, particularly with vascularity, indicate borderline or malignant varieties. Endometrioid and clear cell carcinomas can arise within endometriomas. Fibrous tumors (cystadenofibroma, adenofibroma, fibroma or fibrothecoma, and Brenner tumors) demonstrate low T2-weighted signal intensity of their solid components, while teratomas contain lipid. The nonspecific imaging appearance of additional malignant ovarian germ cell tumors can be narrowed with tumor marker profiles. Sex cord-stromal tumors are often solid, and secondary signs from their hormonal secretion can be a clue to their diagnosis. The authors review the anatomy of the ovary and distal fallopian tube, the proposed origins of the histologic subtypes of tumors, the clinical features and epidemiology of ovarian neoplasms, and the applications of US, CT, and MRI in imaging ovarian neoplasms. The main focus is on the radiologic and pathologic features of the multiple ovarian neoplasm subtypes. An algorithmic approach to the diagnosis of ovarian neoplasms is presented. Online supplemental material is available for this article. ^©RSNA, 2020.

Specialist oncological surgery for removal of the ovaries and fallopian tubes in BRCA1 and BRCA2 pathogenic variant carriers may reduce primary peritoneal cancer risk to very low levels

Risk‐reducing bilateral salpingo‐oophorectomy (RRBSO) is highly effective for the prevention of high‐grade serous ovarian cancer (HGSOC) in BRCA1/2 pathogenic variant carriers (PVCs), but does not completely eliminate future risk of primary peritoneal cancer (PPC). The requirement to completely remove fallopian tubes at RRBSO and carefully exclude occult cancer/serous tubal intraepithelial carcinoma (STIC) lesions may not have been appreciated historically. We calculated rates of HGSOC and PPC in confirmed BRCA1/2 PVCs registered on the regional database in those who did (cases) and did not (controls) undergo RRBSO after genetic testing. Expected annual rates of ovarian/peritoneal cancer were 1% for BRCA1 ≥ 35 years and 0.5% for BRCA2 ≥ 45 years. Follow‐up before 35/45 years was “risk free” and lead time excluded RRBSO <35 years and <45 years for BRCA1 and BRCA2, respectively. Women were followed from personal mutation report (controls) or RRBSO (cases) to death, ovarian/peritoneal cancer or last follow‐up, whichever was sooner. In total, 891 cases (BRCA1 = 468, BRCA2 = 423) and 1302 controls had follow‐up ≥35 years (BRCA1 = 736) and ≥45 years (BRCA2 = 566), respectively, over a total of 7261.1 risk eligible years (mean = 8.15 years). Twenty‐one occult ovarian cancers were found at RRBSO (2.4%), 16 at stage 1. Post RRBSO, 56.97 ovarian/peritoneal cancers were expected but only 3 were observed (HR = 0.053; 95% CI = 0.013‐0.14), with combined Kaplan‐Meier analysis HR = 0.029 (95% CI = 0.009‐0.100, P < .001). Risk reduction was greater in specialist (HR = 0.03; 95% CI = 0.001‐0.13) compared to non‐specialist centres (HR = 0.11; 95% CI = 0.02‐0.37) (P = .07). In controls, 23.35 ovarian/peritoneal cancers were expected with 32 observed (HR = 1.37; 95% CI = 0.95‐1.91). RRBSO <35/<45 years reduces the risk of ovarian/peritoneal cancer by 95% in BRCA1/2 PVCs and may be greater in specialist centres.

What's new?

Women who carry genetic variants in BRCA1/2 that are linked to high‐grade serous ovarian cancer are advised to undergo risk‐reducing prophylactic bilateral salpingo‐oophorectomy (RRBSO). RRBSO, however, is associated with a significant residual risk of primary peritoneal cancer (PPC). Here, the rate of PPC following prophylactic surgery for high‐grade serous ovarian cancer was investigated among 2,193 BRCA1/2 mutation carriers who had undergone RRBSO. Estimates indicate that prophylactic surgery reduced the overall risk of PPC by 95 percent, a far greater reduction than previously described. Residual risk was lowest when RRBSO was carried out at specialist centers compared to non‐specialist centers.

Clinicopathological and molecular analyses of linearly expanded epithelial cells with β-catenin alterations, "β-catenin signature", in the normal fallopian tube

AIMS

Recent advances in next-generation sequencing have made it clear that clonal expansion of cells harbouring driver gene mutations occurs in physiologically normal epithelium. Molecular analysis of tubal epithelium has been almost exclusively confined to the TP53 pathway, which is involved in serous carcinogenesis. Other oncogenic events have not been explored in detail. Here, we report the linear expansion of fallopian tubal epithelial cells exhibiting an altered β-catenin profile (β-catenin signature). Through molecular analyses, we determined the incidence and clinicopathological significance of β-catenin signatures.

METHODS AND RESULTS

We evaluated 64 specimens of surgically removed bilateral fallopian tubes. Thirty-three β-catenin signatures were identified in 13 cases (20.3%); these patients were significantly younger than those without β-catenin signatures (median ages of 44 and 57 years, respectively, P = 0.0317). No correlation between β-catenin signature and any clinical factor was observed. CTNNB1 mutations were detected in three of eight β-catenin signatures when tissues were microdissected and subjected to Sanger sequencing in two representative cases.

CONCLUSIONS

This is the first report of the CTNNB1 mutation in clusters of morphologically bland tubal epithelial cells. The results of this study indicate that β-catenin signatures are common, and they may be a part of diverse molecular alterations occurring in normal tubal epithelium.

Pathology of Hereditary Breast and Ovarian Cancer

Hereditary breast and ovarian cancer (HBOC) syndrome is most commonly characterized by deleterious germline mutations in BRCA1 and BRCA2. HBOC patients are prone to the development of malignant neoplasms in multiple organs including the breast, ovary, and fallopian tube. From a pathological perspective, a number of morphological features have been described in BRCA-associated breast and tubo-ovarian cancers. For example, breast cancers diagnosed in BRCA1-mutation carriers are frequently of a high Nottingham grade and display medullary morphology and a triple-negative and/or a basal-like immunophenotype. In contrast, breast cancers in BRCA2-mutation carriers are similar to sporadic luminal-type tumors that are positive for hormone receptors and lack expression of human epidermal growth factor receptor 2. Cancers arising in the fallopian tube and ovary are almost exclusively of a high-grade serous histotype with frequent Solid, pseudo-Endometrioid, and Transitional cell carcinoma-like morphology (“SET features”), marked nuclear atypia, high mitotic index, abundant tumor infiltrating lymphocytes, and necrosis. In addition, pushing or infiltrative micropapillary patterns of invasion have been described in BRCA-associated metastases of tubo-ovarian high-grade serous carcinomas. Besides BRCA1 and BRCA2 mutations, alterations in a number of other homologous recombination genes with moderate penetrance, including PALB2, RAD51C, RAD51D, BRIP1, and others, have also been described in HBOC patients with varying frequency; however, distinct morphological characteristics of these tumors have not been well characterized to date. In this review, the above pathological features are discussed in detail and a focus is placed on how accurate pathologic interpretation plays an important role in allowing HBOC patients to receive the best possible management.

Molecular Oncology of Gynecologic Tumors

Oncologists and pathologists alike have recognized that the broad histologic categories, especially for ovarian and endometrial carcinomas, do not reliably segregate groups with similar clinical courses or responses to therapeutic interventions. During the last decade a paradigm shift was invoked when the results from The Cancer Genome Atlas (TCGA) project were published. Comprehensive genomic profiling data from TCGA has shown that there are four molecular subgroups of endometrioid carcinomas instead of the two subtypes proposed by Bokhman in the 1970s. For ovarian carcinomas (OC) it is now evident that molecular parameters are also significant. Although traditionally referred to as a single entity, OC is not a homogeneous disease but rather a group of diseases, each with different morphology and biologic behavior. Similar to endometrial cancers, advanced cervical cancer and recurrent disease remain particularly problematic due to chemotherapy resistance. Effective prophylactic vaccines against the most important carcinogenic human papillomaviruses (HPV) types are available, but uptake remains poor. The E6 and E7 oncoproteins are attractive targets for cancer therapy. They are constitutively expressed in HPV-positive tumors, specific to the tumor, functionally important to the tumor cells and recognized by the adaptive immune system as tumor antigens. This review summarizes recent advances in the molecular pathology, which have greatly improved our understanding of the biology of gynecologic cancers.

Modelling Epithelial Ovarian Cancer in Mice: Classical and Emerging Approaches

High-grade serous epithelial ovarian cancer (HGSC) is the most aggressive subtype of epithelial ovarian cancer. The identification of germline and somatic mutations along with genomic information unveiled by The Cancer Genome Atlas (TCGA) and other studies has laid the foundation for establishing preclinical models with high fidelity to the molecular features of HGSC. Notwithstanding such progress, the field of HGSC research still lacks a model that is both robust and widely accessible. In this review, we discuss the recent advancements and utility of HGSC genetically engineered mouse models (GEMMs) to date. Further analysis and critique on alternative approaches to modelling HGSC considers technological advancements in somatic gene editing and modelling prototypic organs, capable of tumorigenesis, on a chip.

How to manage BRCA mutation carriers?

Inherited mutations in BRCA1 and BRCA2 genes increase the risk of development of cancer in organs especially in breast and ovary. Prevention and screening in BRCA mutation carriers are of high importance. Prophylactic surgeries are possible but are still insufficiently performed because they require surgical procedures in healthy patients. Guidelines for the management of BRCA mutations carriers must absolutely be part of the standard practice of all those involved in the management of these patients to increase the impact of the implementation of these preventive measures. There is no screening recommended for ovarian cancer. A risk-reducing bilateral salpingo-oophorectomy should be performed from age 35 to 40 years for BRCA1 mutation carriers and 40 to 45 years for BRCA2 mutation carriers. A screening for breast cancer should be performed annually from 30 years old by breast MRI and mammography. A risk-reducing bilateral mastectomy is recommended with nipple sparing mastectomy and immediate breast reconstruction from 30 years and before 40 years. A multidisciplinary care must be implemented for these patients with an important psychological support.

ALDH1A1+ ovarian cancer stem cells co-expressing surface markers CD24, EPHA1 and CD9 form tumours in vivo

One of the reasons for recurrence following treatment of high grade serous ovarian carcinoma (HGSOC) is the persistence of residual cancer stem cells (CSCs). There has been variability between laboratories in the identification of CSC markers for HGSOC. We have identified new surface markers (CD24, CD9 and EPHA1) in addition to those previously known (CD44, CD117 and CD133) using a bioinformatics approach. The expression of these surface markers was evaluated in ovarian cancer cell lines, primary malignant cells (PMCs), normal ovary and HGSOC. There was no preferential expression of any of the markers or a combination. All the markers were expressed at variable levels in ovarian cancer cell lines and PMCs. Only CD117 and CD9 were expressed in the normal ovarian surface epithelium and fallopian tube. Both ALDEFLUOR (ALDH1A1) and side population assays identified a small proportion of cells (<3%) separately that did not overlap with little variability in cell lines and PMCs. All surface markers were co-expressed in ALDH1A1+ cells without preference for one combination. The cell cycle analysis of ALDH1A1+ cells alone revealed that majority of them reside in G0/G1 phase of cell cycle. Further separation of G0 and G1 phases showed that ALDH1A1+ cells reside in G1 phase of the cell cycle. Xenograft assays showed that the combinations of ALDH1A1 + cells co-expressing CD9, CD24 or EPHA1 were more tumorigenic and aggressive with respect to ALDH1A1-cells. These data suggest that a combined approach could be more useful in identifying CSCs in HGSOC.

Why the dual origins of high grade serous ovarian cancer matter

Utilising identical genetic aberrations but targeting different cells, Zhang and colleagues seek to uncover how the cell of origin influences high-grade serous ovarian cancer biology, metastasis and response to treatment.

Fallopian tube initiation of high grade serous ovarian cancer and ovarian metastasis: Mechanisms and therapeutic implications

Ovarian cancer is the most lethal gynecologic malignancy and the fifth leading cause of cancer-related death in women. Although outcomes have improved in recent years, there remains an unmet clinical need to understand the early pathogenesis of ovarian cancer in order to identify new diagnostic approaches and agents of chemoprevention and chemotherapy. While high grade serous ovarian cancer (HGSOC), the most abundant histotype, was initially thought to arise from the ovarian surface epithelium, there is an increasing body of evidence suggesting that HGSOC originates in the fallopian tube. With this new understanding of cell of origin, understanding of disease development requires analysis with a novel perspective. Currently, factors that drive the initiation and migration of dysplastic tubal epithelial cells from the fallopian tube to the ovary are not yet fully defined. These factors include common mutations to fallopian tube epithelial cells, as well as factors originating from both the fallopian tube and ovary which are capable of inducing transformation and dissemination in said cells. Here, we review these changes, their causative agents, and various potential means of intervention.

Serous Tubal Intraepithelial Carcinoma: A Concise Review for the Practicing Pathologist and Clinician

Ovarian cancer is the deadliest gynecologic malignancy, accounting for more than 14,000 deaths each year. With no established way to prevent or screen for it, the vast majority of cases are diagnosed as International Federation of Gynecology and Obstetrics (FIGO) stage III or higher. Individuals with germline BRCA mutations are at particularly high risk for epithelial ovarian cancer and have been the subject of many risk-reducing strategies. In the past ten years, studies looking at risk-reducing salpingo-oophorectomy (RRSO) in this population have uncovered an interesting association: up to 8% of women with BRCA1 or BRCA2 mutations who underwent RRSO had an associated serous tubal intraepithelial carcinoma (STIC). The importance of this finding is highlighted by the fact that up to 60% of ovarian cancer patients will also have an associated STIC. These studies have led to a paradigm shift that a subset of epithelial ovarian cancer originates not in the ovarian epithelium, but rather in the distal fallopian tube. In response to this, many providers have changed their practice by expanding the role of routine salpingectomy, hysterectomy, and sterilization procedures. The American College of Obstetricians and Gynecologists (ACOG) has acknowledged opportunistic salpingectomy as a safe strategy to reduce the risk of epithelial ovarian cancer in Committee Opinion #774. It is thus important for pathologists and clinicians to understand the definition of STIC; how it is diagnosed; and, most importantly, its clinical significance.

Evidence of a Monoclonal Origin for Bilateral Serous Tubal Intraepithelial Neoplasia

Serous tubal intraepithelial carcinoma (STIC) is found in 10% to 60% of cases of tuboovarian high-grade serous carcinoma (HGSC) and is presumed to be the site of origin, linking many HGSCs to the fallopian tube. Bilateral STIC is present in ∼20% of cases. Because clonal Tp53 mutations are a defining feature of HGSC, including their associated STICs, we analyzed 4 cases of bilateral serous tubal intraepithelial neoplasia (STIN), including STIC and Tp53-mutated serous tubal intraepithelial lesions (STILs), associated with HGSC to determine whether they contained the same or different p53 mutations. Extracted DNA from STINs, concurrent HGSCs and control tissues was analyzed for mutations in all exons of Tp53. Sequencing was successful in 3 of the 4 cases, and an identical Tp53 mutation was detected in the HGSC and bilateral STINs in 2 of these 3 cases. One STIN was morphologically a STIL. These findings confirm that a subset of bilateral STINs share the same Tp53 mutation, implying that at least one of the STINs is an intraepithelial metastasis from either the contralateral STIN or HGSC. This study complements others addressing the multiple origins of STIN in the setting of existing HGSC. It further underscores the fact that potential overlap in biologic behavior between STILs and STICs as well as timing and direction of metastatic spread has yet to be resolved.

Incidence of germline BRCA1/2 mutations in women with tubo-ovarian high-grade serous carcinomas with and without serous tubal intra-epithelial carcinomas

OBJECTIVE

To compare the germline BRCA1 and BRCA2 mutation (gBRCA) status in women with high-grade serous tubo-ovarian and primary peritoneal carcinoma with and without serous tubal intra-epithelial carcinomas (serous tubal intra-epithelial carcinoma-positive vs serous tubal intra-epithelial carcinoma-negative).

MATERIALS AND METHODS

A retrospective study was performed of patients in Western Australia diagnosed with high-grade serous tubo-ovarian and primary peritoneal carcinoma and referred for genetic counseling and gBRCA testing from July 1, 2014 to June 30, 2017. Histopathology reports were reviewed to ascertain whether serous tubal intra-epithelial carcinoma was present. Personal or family gBRCA status, family history, age at diagnosis, mode of treatment (neoadjuvant chemotherapy vs primary surgery), and stage were also recorded.

RESULTS

A total of 269 women with high-grade serous tubo-ovarian and primary peritoneal carcinoma were referred for genetic counseling and testing. 114 patients were excluded because the serous tubal intra-epithelial carcinoma status was not assessable or because patients did not attend for genetic assessment. 155 patients (55 serous tubal intra-epithelial carcinoma-positive and 100 serous tubal intra-epithelial carcinoma-negative) underwent genetic testing. gBRCA mutations were found in 27.8% of serous tubal intra-epithelial carcinoma-positive patients compared with 14.0% of serous tubal intra-epithelial carcinoma-negative patients (p=0.094). Of those found to have a gBRCA mutation, 89.7% reported a positive personal or family history of BRCA-related cancers.

CONCLUSIONS

The gBRCA mutation detection rate in serous tubal intra-epithelial carcinoma-positive patients was nearly double that of serous tubal intra-epithelial carcinoma-negative patients. Factors such as a positive family history of BRCA-related cancers were seen at a higher proportion in the mutation positive women.

The Many Microenvironments of Ovarian Cancer

High-grade serous ovarian cancer (HGSOC) is the most common and deadly subtype of ovarian cancer as it is commonly diagnosed after substantial metastasis has already occurred. The past two decades have been an active era in HGSOC research, with new information on the origin and genomic signature of the tumor cell. Additionally, studies have begun to characterize changes in the HGSOC microenvironment and examine the impact of these changes on tumor progression and response to therapies. While this knowledge may provide valuable insight into better prognosis and treatments for HGSOCs, its collection, synthesis, and application are complicated by the number of unique microenvironments in the disease-the initiating site (fallopian tube), first metastasis (ovary), distal metastases (peritoneum), and recurrent/platinum-resistant setting. Here, we review the state of our understanding of these diverse sites and highlight remaining questions.

Ovarian Cancer Dissemination-A Cell Biologist's Perspective

Epithelial ovarian cancer (EOC) comprises multiple disease states representing a variety of distinct tumors that, irrespective of tissue of origin, genetic aberrations and pathological features, share common patterns of dissemination to the peritoneal cavity. EOC peritoneal dissemination is a stepwise process that includes the formation of malignant outgrowths that detach and establish widespread peritoneal metastases through adhesion to serosal membranes. The cell biology associated with outgrowth formation, detachment, and de novo adhesion is at the nexus of diverse genetic backgrounds that characterize the disease. Development of treatment for metastatic disease will require detailed characterization of cellular processes involved in each step of EOC peritoneal dissemination. This article offers a review of the literature that relates to the current stage of knowledge about distinct steps of EOC peritoneal dissemination, with emphasis on the cell biology aspects of the process.

PAX8 expression in high-grade serous ovarian cancer positively regulates attachment to ECM via Integrin β3

Background

Ovarian cancer is the third most common cause of death among gynecologic malignancies worldwide. Understanding the biology and molecular pathogenesis of ovarian epithelial tumors is key to developing improved prognostic indicators and effective therapies. We aimed to determine the effects of PAX8 expression on the migrative, adhesive and survival capabilities of high-grade serous carcinoma cells.

Methods

PAX8 depleted Fallopian tube secretory cells and ovarian cancer cells were generated using short interfering siRNA. Anoikis resistance, cell migration and adhesion properties of PAX8 silenced cells were analyzed by means of specific assays. Chromatin immunoprecipitation (ChIP) was carried out using a PAX8 polyclonal antibody to demonstrate that PAX8 is able to bind to the 5′-flanking region of the ITGB3 gene positively regulating its expression.

Results

Here, we report that RNAi silencing of PAX8 sensitizes non-adherent cancer cells to anoikis and affects their tumorigenic properties. We show that PAX8 plays a critical role in migration and adhesion of both Fallopian tube secretory epithelial cells and ovarian cancer cells. Inhibition of PAX8 gene expression reduces the ability of ovarian cancer cells to migrate and adhere to the ECM and specifically to fibronectin and/or collagen substrates. Moreover, loss of PAX8 strongly reduces ITGB3 expression and consequently the correct expression of the αvβ3 heterodimer on the plasma membrane.

Conclusions

Our results demonstrate that PAX8 modulates the interaction of tumor cells with the extracellular matrix (ECM). Notably, we also highlight a novel pathway downstream this transcription factor. Overall, PAX8 could be a potential therapeutic target for high-grade serous carcinoma.

Defining fallopian tube-derived miRNA cancer signatures

BACKGROUND

MicroRNAs have recently emerged as promising circulating biomarkers in diverse cancer types, including ovarian cancer. We utilized conditional, doxycycline-induced fallopian tube (FT)-derived cancer models to identify changes in miRNA expression in tumors and plasma, and further validated the murine findings in high-grade ovarian cancer patient samples.

METHODS

We analyzed 566 biologically informative miRNAs in doxycycline-induced FT and metastatic tumors as well as plasma samples derived from murine models bearing inactivation of Brca, Tp53, and Pten genes. We identified miRNAs that showed a consistent pattern of dysregulated expression and validated our results in human patient serum samples.

RESULTS

We identified six miRNAs that were significantly dysregulated in doxycycline-induced FTs (P < .05) and 130 miRNAs differentially regulated in metastases compared to normal fallopian tissues (P < .05). Furthermore, we validated miR-21a-5p, miR-146a-5p, and miR-126a-3p as dysregulated in both murine doxycycline-induced FT and metastatic tumors, as well as in murine plasma and patient serum samples.

CONCLUSIONS

In summary, we identified changes in miRNA expression that potentially accompany tumor development in murine models driven by commonly found genetic alterations in cancer patients. Further studies are required to test both the function of these miRNAs in driving the disease and their utility as potential biomarkers for diagnosis and/or disease progression.

Identification of a Prognostic Signature Associated With DNA Repair Genes in Ovarian Cancer

Introduction: Ovarian cancer is a highly malignant cancer with a poor prognosis. At present, there is no accurate strategy for predicting the prognosis of ovarian cancer. A prognosis prediction signature associated with DNA repair genes in ovarian cancer was explored in this study.

Methods: Gene expression profiles of ovarian cancer were downloaded from the GEO, UCSC, and TCGA databases. Cluster analysis, univariate analysis, and stepwise regression were used to identify DNA repair genes as potential targets and a prognostic signature for ovarian cancer survival prediction. The top genes were evaluated by immunohistochemical staining of ovarian cancer tissues, and external data were used to assess the signature.

Results: A total of 28 DNA repair genes were identified as being significantly associated with overall survival (OS) among patients with ovarian cancer. The results showed that high expression of XPC and RECQL and low expression of DMC1 were associated with poor prognosis in ovarian cancer patients. The prognostic signature combining 14 DNA repair genes was able to separate ovarian cancer samples associated with different OS times and showed robust performance for predicting survival (Training set: p < 0.0001, AUC = 0.759; Testing set: p < 0.0001, AUC = 0.76).

Conclusion: Our study identified 28 DNA repair genes related to the prognosis of ovarian cancer. Using some of these potential biomarkers, we constructed a prognostic signature to effectively stratify ovarian cancer patients with different OS rates, which may also serve as a potential therapeutic target in ovarian cancer.

No. 344-Opportunistic Salpingectomy and Other Methods of Risk Reduction for Ovarian/Fallopian Tube/Peritoneal Cancer in the General Population

OBJECTIVE

This guideline reviews the potential benefits of opportunistic salpingectomy to prevent the development of high grade serous cancers (HGSC) of the ovary/fallopian tube/peritoneum based on current evidence supporting the fallopian tube origin of disease.

INTENDED USERS

Gynaecologists, obstetricians, family doctors, registered nurses, nurse practitioners, residents, and health care providers.

TARGET POPULATION

Adult women (18 and older): OPTIONS: Women considering hysterectomy who wish to retain their ovaries in situ have traditionally also retained their fallopian tubes. In addition, women undergoing permanent surgical sterilization have usually undergone tubal ligation using various methods rather than undergoing surgical removal of the entire fallopian tube.

EVIDENCE

For the sections "Evidence Supporting the Hypothesis That HGSC Originates in the Fallopian Tube" and "Current Literature on the Effects and Safety of Opportunistic Salpingectomy," relevant studies were searched in PubMed, Medline, and the Cochrane Systematic Reviews using the following terms, either alone or in combination, with the search limited to English language materials: "high grade serous cancers ovary," "fallopian tube," "peritoneum," "opportunistic salpingectomy," "epithelial ovarian cancers," "origin," "tubal carcinoma in situ," "BRCA mutation," "prophylactic salpingectomy," "inflammation," "clear cell," and "endometrioid." The initial search was performed in March 2015 with a final literature search in March 2016. Relevant evidence was selected for inclusion in the following order: meta-analyses, systematic reviews, guidelines, randomized controlled trials, prospective cohort studies, observational studies, non-systematic reviews, case series, and reports. The total number of studies identified was 458, and 56 studies were included in this review. For the section "Other Factors Influencing the Risk of Developing "Ovarian" Cancers" a general Medline search was carried out using the terms "ovarian neoplasm" and "prevention." The search included papers published from December 2005 to March 2016. Meta-analyses were preferentially selected except where no such review was found. Additional searches for each subheading were also conducted (e.g., "ovarian neoplasm" and "tubal ligation.") Additional significant articles were identified through cross-referencing the identified reviews. For the search for "ovarian neoplasm" and "prevention," 10 meta-analyses were identified. For the search for "ovarian neoplasm" and "tubal ligation," an additional 4 meta-analyses were identified.

VALIDATION METHODS

The content and recommendations were drafted and agreed on by the principal authors. The Executive and Board of the Society of Gynecologic Oncology of Canada reviewed the content and submitted comments for consideration, and the Board of the SOGC approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development and Evaluation methodology framework (Table 1). The interpretation of strong and weak recommendations is described in Table 2. The summary of findings is available on request.

BENEFITS, HARMS, AND/OR COSTS

The addition of opportunistic salpingectomy to a planned hysterectomy or permanent sterilization did not increase rates of hospital readmission (OR 0.91, 95% CI 0.75 to 1.10 and OR 0.8, 95% CI 0.56 to 1.21, respectively) or blood transfusions (OR 0.86, 95% CI 0.67 to 1.10 and OR 0.75, 95% CI 0.32 to 1.73, respectively) but did increase the overall operating time (by 16 minutes and 10 minutes, respectively) in a retrospective review of 43 931 women. The risk of repeat surgery for tubal pathology among women with retained fallopian tubes after hysterectomy was at least doubled (OR 2.13, 95% CI 1.88 to 2.42 in a population-based study of 170 000 women). If general gynaecologists were to consider removal of fallopian tubes at the time of every hysterectomy and sterilization procedure with referral of all patients with HGSC for hereditary cancer counselling and genetic testing, experts project a potential reduction in the rate of HGSC by 40% over the next 20 years.

GUIDELINE UPDATE

Evidence will be reviewed 5 years after publication to decide whether all or part of the guideline should be updated. However, if important new evidence is published prior to the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations.

SPONSORS

This guideline was developed with resources funded by the Society of Gynecologic Oncology of Canada and SOGC.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Cytomorphologic and molecular analyses of fallopian tube fimbrial brushings for diagnosis of serous tubal intraepithelial carcinoma

BACKGROUND

The paradigm shift localizing the origin of ovarian high-grade serous carcinoma (HGSC) to the fallopian tube underscores the rationale for meticulous microscopic examination of salpingectomy specimens. The precursor, termed "serous tubal intraepithelial carcinoma," is often a focal lesion, which poses difficulties for histologic diagnosis.

METHODS

The authors describe a method to examine exfoliated epithelial cells from fallopian tube fimbria by gentle brushing, thereby enabling thorough sampling of the mucosal surface. Fimbrial brushings were collected from 20 fresh salpingectomy specimens from 15 patients, including 5 who had pathologically confirmed ovarian HGSC. Samples taken only from tubes that were grossly negative for tumor were processed for Papanicolaou staining, p53 immunocytochemistry, and tumor protein 53 (TP53) mutation analysis.

RESULTS

Cells with malignant cytomorphologic features were identified only in tubal brushings from patients with ovarian HGSC. In all cases, atypical/malignant cells on cytology corresponded to lesions with similar morphology and immunostaining pattern in permanent sections, demonstrating the sensitivity of the technique while providing reassurance that specimen integrity was not disrupted by the procedure. Targeted next-generation sequencing confirmed the presence of TP53 mutations in fimbrial brushings from HGSC, but not in benign samples, and demonstrated concordance with the immunostaining pattern. Identical mutations were observed in matched lesions microdissected from formalin-fixed tissue sections.

CONCLUSIONS

The described technique enables cytologic evaluation of the fallopian tube fimbria for a diagnosis of serous tubal intraepithelial carcinoma, serving as a complement to histology while offering distinct advantages with respect to the procurement of cellular material for ancillary testing and research.

Fallopian Tube Epithelial Changes in Ovarian Serous Tumors Compared with Control Group: A Single-Center Study

BACKGROUND

Recent studies have hypothesized that distal end of fallopian tube is a possible origin of ovarian serous carcinoma. This study investigated histopathological changes in fallopian tube epithelium (FTE) of the patients with ovarian serous tumors compared with control group.

MATERIALS AND METHODS

In a prospective cross-sectional study, fallopian tubes (right and left) of 34 cases with ovarian serous tumors were collected from patients who underwent surgery in two major gynecological centers affiliated to Shiraz University of Medical Sciences, Shiraz, Iran (2012-2015). They are composed of 21 (61.8%) high-grade serous carcinomas (HGSCs), 5 (14.7%) borderline ones, and 8 (23.5%) benign serous tumors. As control group, fallopian tubes of 72 hystrectomy cases without ovarian tumor were added to the study. Both tubes of all of the cases were submitted entirely, according to the protocol of sectioning and extensively examining the fimbriated end. The results were statistically analyzed using SPSS-PC windows and Chi-square tests.

RESULTS

Significant differences were found between the cases and control group in tubal epithelial cell stratification (especially >3 cell layers thickness), atypia, mitosis, glandular complexity, tufting, and detached epithelial cells (P < 0.05). These findings particularly atypia and mitosis were more frequently seen in the ampulla and fimbriated end of high-grade ovarian serous carcinomas.

CONCLUSION

Our results showed that premalignant epithelial changes of the ampulla and the distal end of FTE were seen in some of the patients with ovarian HGSCs. Therefore, FTE could be one of the sources of ovarian serous carcinoma.

Frontiers in the Pathology and Pathogenesis of Ovarian Cancer: Cancer Precursors and "Precursor Escape"

This article summarizes the pathogenesis of ovarian carcinoma, focusing on the paradox of high-grade serous carcinogenesis. The fallopian tube is the prime site of origin in early serous cancers. Because a subset of serous cancers is associated with early serous proliferations absent intramucosal carcinomas, "precursor escape" is emerging, whereby some advanced cancers trace their roots to early serous proliferations. This has parallels in the endometriosis model and opens up a novel mechanism by which advanced malignancy could emerge without an obvious tubal carcinoma. The impact of this concept on classification of serous cancer and expectations from preventive strategies are discussed.

Targeted metabolomic profiling of low and high grade serous epithelial ovarian cancer tissues: a pilot study

INTRODUCTION

Epithelial ovarian cancer (EOC) remains the leading cause of death from gynecologic malignancies and has an alarming global fatality rate. Besides the differences in underlying pathogenesis, distinguishing between high grade (HG) and low grade (LG) EOC is imperative for the prediction of disease progression and responsiveness to chemotherapy.

OBJECTIVES

The aim of this study was to investigate, the tissue metabolome associated with HG and LG serous epithelial ovarian cancer.

METHODS

A combination of one dimensional proton nuclear magnetic resonance (1D H NMR) spectroscopy and targeted mass spectrometry (MS) was employed to profile the tissue metabolome of HG, LG serous EOCs, and controls.

RESULTS

Using partial least squares-discriminant analysis, we observed significant separation between all groups (p < 0.05) following cross validation. We identified which metabolites were significantly perturbed in each EOC grade as compared with controls and report the biochemical pathways which were perturbed due to the disease. Among these metabolic pathways, ascorbate and aldarate metabolism was identified, for the first time, as being significantly altered in both LG and HG serous cancers. Further, we have identified potential biomarkers of EOC and generated predictive algorithms with AUC (CI) = 0.940 and 0.929 for HG and LG, respectively.

CONCLUSION

These previously unreported biochemical changes provide a framework for future metabolomic studies for the development of EOC biomarkers. Finally, pharmacologic targeting of the key metabolic pathways identified herein could lead to novel and effective treatments of EOC.