Serous tubal intraepithelial carcinomas associated with high-grade serous ovarian carcinomas: a systematic review

Somatostatin and Somatostatin Receptors in Tumour Biology

Somatostatin (SST), a growth hormone inhibitory peptide, is expressed in endocrine and non-endocrine tissues, immune cells and the central nervous system (CNS). Post-release from secretory or immune cells, the first most appreciated role that SST exhibits is the antiproliferative effect in target tissue that served as a potential therapeutic intervention in various tumours of different origins. The SST-mediated in vivo and/or in vitro antiproliferative effect in the tumour is considered direct via activation of five different somatostatin receptor subtypes (SSTR1-5), which are well expressed in most tumours and often more than one receptor in a single cell. Second, the indirect effect is associated with the regulation of growth factors. SSTR subtypes are crucial in tumour diagnosis and prognosis. In this review, with the recent development of new SST analogues and receptor-specific agonists with emerging functional consequences of signaling pathways are promising therapeutic avenues in tumours of different origins that are discussed.

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.

Consensus based recommendations for the diagnosis of serous tubal intraepithelial carcinoma: an international Delphi study

AIM

Reliably diagnosing or safely excluding serous tubal intraepithelial carcinoma (STIC), a precursor lesion of tubo-ovarian high-grade serous carcinoma (HGSC), is crucial for individual patient care, for better understanding the oncogenesis of HGSC, and for safely investigating novel strategies to prevent tubo-ovarian carcinoma. To optimize STIC diagnosis and increase its reproducibility, we set up a three-round Delphi study.

METHODS AND RESULTS

In round 1, an international expert panel of 34 gynecologic pathologists, from 11 countries, was assembled to provide input regarding STIC diagnosis, which was used to develop a set of statements. In round 2, the panel rated their level of agreement with those statements on a 9-point Likert scale. In round 3, statements without previous consensus were rated again by the panel while anonymously disclosing the responses of the other panel members. Finally, each expert was asked to approve or disapprove the complete set of consensus statements. The panel indicated their level of agreement with 64 statements. A total of 27 statements (42%) reached consensus after three rounds. These statements reflect the entire diagnostic work-up for pathologists, regarding processing and macroscopy (three statements); microscopy (eight statements); immunohistochemistry (nine statements); interpretation and reporting (four statements); and miscellaneous (three statements). The final set of consensus statements was approved by 85%.

CONCLUSION

This study provides an overview of current clinical practice regarding STIC diagnosis amongst expert gynecopathologists. The experts' consensus statements form the basis for a set of recommendations, which may help towards more consistent STIC diagnosis.

Prophylactic Radical Fimbriectomy with Delayed Oophorectomy in Women with a High Risk of Developing an Ovarian Carcinoma: Results of a Prospective National Pilot Study

Risk-reducing salpingo-oophorectomy is the gold standard for the prophylaxis of ovarian cancer in high-risk women. Due to significant adverse effects, 20-30% of women delay or refuse early oophorectomy. This prospective pilot study (NCT01608074) aimed to assess the efficacy of radical fimbriectomy followed by a delayed oophorectomy in preventing ovarian and pelvic invasive cancer (the primary endpoint) and to evaluate the safety of both procedures. The key eligibility criteria were pre-menopausal women ≥35 years with a high risk of ovarian cancer who refused a risk-reducing salpingo-oophorectomy. All the surgical specimens were subjected to the SEE-FIM protocol. From January 2012 to October 2014, 121 patients underwent RF, with 51 in an ambulatory setting. Occult neoplasia was found in two cases, with one tubal high-grade serous ovarian carcinoma. Two patients experienced grade 1 intraoperative complications. No early or delayed grade ≥3 post-operative complications occurred. After 7.3 years of median follow-up, no cases of pelvic invasive cancer have been noted. Three of the fifty-two patients developed de novo breast cancer. One BRCA1-mutated woman delivered twins safely. Twenty-five patients underwent menopause, including fifteen who had received chemotherapy for breast cancer, and twenty-three underwent menopause before the delayed oophorectomy, while two did not undergo a delayed oophorectomy at all. Overall, 46 women underwent a delayed oophorectomy. No abnormalities were found in any delayed oophorectomy specimens. Radical fimbriectomy followed by delayed oophorectomy appears to be a safe and well-tolerated risk-reducing approach, which avoids early menopause for patients with a high risk of breast and ovarian cancer.

Search for New Participants in the Pathogenesis of High-Grade Serous Ovarian Cancer with the Potential to Be Used as Diagnostic Molecules

Recent studies have attempted to develop molecular signatures of epithelial ovarian cancer (EOC) based on the quantitation of protein-coding and non-coding RNAs to predict disease prognosis. Due to the heterogeneity of EOC, none of the developed prognostic signatures were directly applied in clinical practice. Our work focuses on high-grade serous ovarian carcinoma (HGSOC) due to the highest mortality rate relative to other types of EOC. Using deep sequencing of small non-coding RNAs in combination with quantitative real-time PCR, we confirm the dualistic classification of epithelial ovarian cancers based on the miRNA signature of HGSOC (type 2), which differs from benign cystadenoma and borderline cystadenoma-precursors of low-grade serous ovarian carcinoma (type 1)-and identified two subtypes of HGSOC, which significantly differ in the level of expression of the progesterone receptor in the tumor tissue, the secretion of miR-16-5p, miR-17-5p, miR-93-5p, miR-20a-5p, the level of serum CA125, tumor size, surgical outcome (optimal or suboptimal cytoreduction), and response to chemotherapy. It was found that the combined determination of the level of miR-16-5p, miR-17-5p, miR-20a-5p, and miR-93-5p circulating in blood plasma of patients with primary HGSOC tumors makes it possible to predict optimal cytoreduction with 80.1% sensitivity and 70% specificity (p = 0.022, TPR = 0.8, FPR = 0.3), as well as complete response to adjuvant chemotherapy with 77.8% sensitivity and 90.9% specificity (p = 0.001, TPR = 0.78, FPR = 0.09). After the additional verification of the obtained data in a larger HGSOC patient cohort, the combined quantification of these four miRNAs is proposed to be used as a criterion for selecting patients either for primary cytoreduction or neoadjuvant chemotherapy followed by interval cytoreduction.

Outcome and Management of Serous Tubal Intraepithelial Carcinoma Following Opportunistic Salpingectomy: Systematic Review and Meta-Analysis

OBJECTIVE

Serous ovarian cancer is the most common subtype of epithelial ovarian carcinoma-the most prevalent type of ovarian cancer. High-grade serous ovarian carcinoma (HGSOC) is thought to arise from the distal fallopian tube, with a precursor lesion known as serous tubal intraepithelial carcinoma (STIC). STICs are found in the final pathology of a salpingectomy specimen in 10%-20% of women with a BRCA gene mutation and 1%-7% of women without a mutation. However, there is currently no official guideline and a paucity of data on the management of STICs.

DATA SOURCES

We performed a systematic review following PRISMA guidelines. Five databases were searched for relevant studies on STICs.

STUDY SELECTION

Two independent reviewers performed the abstract and full-text screening and data extraction, with conflicts resolved through discussion with the third reviewer. The risk of bias of each study was assessed using the Newcastle-Ottawa scale.

DATA EXTRACTION AND SYNTHESIS

Fourteen articles were included. Ninety-nine patients who were diagnosed with STIC and subsequently followed for a mean period of 55.5 months were included in this analysis. Eighty-three patients (83.9%) were BRCA mutation carriers. After the diagnosis of isolated STIC, 7 patients (7.3%) received chemotherapy and 25 (26%) underwent surgical staging. Three of the 25 patients were diagnosed with HGSOC based on the staging surgery. Nine patients were later diagnosed with HGSOC during follow-up, with an average duration of follow-up of 58.5 months between the diagnosis of STIC and the diagnosis of HGSOC.

CONCLUSION

Based on our review of the literature, there is a 10.7% risk of having concurrent HGSOC at the time of STIC diagnosis, and the risk of developing a subsequent HGSOC is 14.5%. BRCA mutation status should be determined in cases of isolated STIC, as 83.9% of patients included in this study were found to carry BRCA mutations. We believe it is necessary to further investigate the role of surgical staging following the diagnosis of STIC.

PAX8 as a Potential Target for Ovarian Cancer: What We Know so Far

The Fallopian tube epithelium harbors the origin cells for the majority of high-grade serous ovarian carcinomas (HGSCs), the most lethal form of gynecologic malignancies. PAX8 belongs to the paired-box gene family of transcription factors and it is a marker of the FTE secretory cell lineage. Its role has been investigated in migration, invasion, proliferation, cell survival, stem cell maintenance, angiogenesis and tumor growth. In this review, we focus on the pro-tumorigenic role of PAX8 in ovarian cancer; in this context, PAX8 possibly continues to exert its transcriptional activity on its physiological targets but may also function on newly available targets after the tumorigenic hits. Acquiring new insights into the different PAX8 mechanism(s) of action in the tumor microenvironment could uncover new viable therapeutic targets and thus improve the current treatment regimen.

Molecular catastrophe, the peritoneal cavity and ovarian cancer prevention

The current theory of carcinogenesis for the deadliest of "ovarian" cancers - high-grade serous carcinoma (HGSC) - holds that the malignancy develops first in the fallopian tube and spreads to the ovaries, peritoneum and/or regional lymph nodes. This is based primarily on the observation of early forms of serous neoplasia (serous tubular intraepithelial lesions (STILs), and serous tubular intraepithelial carcinomas (STICS)) in the fimbria of women undergoing risk reduction surgery. However, these lesions are uncommon in the general population, confer a low risk (5%) of HGSC following their removal in at-risk women with germ-line BRCA1/2 mutations and require 4 or more years to recur as intraperitoneal HGSC. These features suggest that isolated STILs and STICs behave as precursors with uncertain cancer risk rather than carcinomas. Their evolution to HGSC after escape from the tube could proceed step-wise with multiple biologic events; however, it is unclear whether immediately adjacent HGSCs in the setting of advanced disease evolved in the same fashion. The latter scenario could also be explained by a "catastrophic" model in which STICs suddenly develop with invasive and metastatic potential, overwhelming or obscuring the site of origin. Moreover, a similar model might explain the sudden emergence of HGSC in the peritoneal cavity following escape of precursor cells years before. Long term follow-up data from opportunistic or prophylactic salpingectomy should shed light on where malignant transformation occurs, as well as the time-line from precursor to metastatic HGSC. This article is protected by copyright. All rights reserved.

Recommendations for diagnosing STIC: a systematic review and meta-analysis

Our understanding of the oncogenesis of high-grade serous cancer of the ovary and its precursor lesions, such as serous tubal intraepithelial carcinoma (STIC), has significantly increased over the last decades. Adequate and reproducible diagnosis of these precursor lesions is important. Diagnosing STIC can have prognostic consequences and is an absolute requirement for safely offering alternative risk reducing strategies, such as risk reducing salpingectomy with delayed oophorectomy. However, diagnosing STIC is a challenging task, possessing only moderate reproducibility. In this review and meta-analysis, we look at how pathologists come to a diagnosis of STIC. We performed a literature search identifying 39 studies on risk reducing salpingo-oophorectomy in women with a known BRCA1/2 PV, collectively reporting on 6833 patients. We found a pooled estimated proportion of STIC of 2.8% (95% CI, 2.0–3.7). We focused on reported grossing protocols, morphological criteria, level of pathologist training, and the use of immunohistochemistry. The most commonly mentioned morphological characteristics of STIC are (1) loss of cell polarity, (2) nuclear pleomorphism, (3) high nuclear to cytoplasmic ratio, (4) mitotic activity, (5) pseudostratification, and (6) prominent nucleoli. The difference in reported incidence of STIC between studies who totally embedded all specimens and those who did not was 3.2% (95% CI, 2.3–4.2) versus 1.7% (95% CI, 0.0–6.2) (p 0.24). We provide an overview of diagnostic features and present a framework for arriving at an adequate diagnosis, consisting of the use of the SEE-FIM grossing protocol, evaluation by a subspecialized gynecopathologist, rational use of immunohistochemical staining, and obtaining a second opinion from a colleague.

Endometrioid Tubal Intraepithelial Neoplasia (E-TIN) of the Fallopian Tube: A Case Series

Although serous tubal intraepithelial carcinoma has been well described in the distal fallopian tube as precancers of pelvic high-grade serous carcinoma, endometrioid precancers have drawn less attention. Recently, endometrioid precursor lesions have been identified and reported to have a specific immunophenotype (PAX2-, ALDH1+, diffuse nuclear beta-catenin), as well as an association with both uterine and ovarian endometrioid carcinomas. These have been referred to as endometrioid (or type II) secretory cell outgrowths. A subset of endometrioid secretory cell outgrowths show architectural complexity resembling hyperplasia of the endometrium and have been referred to as endometrioid tubal intraepithelial neoplasia. We report 4 cases of endometrioid tubal intraepithelial neoplasia with clinical correlation and morphologic differential diagnosis.

Mechanisms of High-Grade Serous Carcinogenesis in the Fallopian Tube and Ovary: Current Hypotheses, Etiologic Factors, and Molecular Alterations

Ovarian high-grade serous carcinomas (HGSCs) are a heterogeneous group of diseases. They include fallopian-tube-epithelium (FTE)-derived and ovarian-surface-epithelium (OSE)-derived tumors. The risk/protective factors suggest that the etiology of HGSCs is multifactorial. Inflammation caused by ovulation and retrograde bleeding may play a major role. HGSCs are among the most genetically altered cancers, and TP53 mutations are ubiquitous. Key driving events other than TP53 mutations include homologous recombination (HR) deficiency, such as BRCA 1/2 dysfunction, and activation of the CCNE1 pathway. HR deficiency and the CCNE1 amplification appear to be mutually exclusive. Intratumor heterogeneity resulting from genomic instability can be observed at the early stage of tumorigenesis. In this review, I discuss current carcinogenic hypotheses, sites of origin, etiologic factors, and molecular alterations of HGSCs.

Single-cell transcriptomics identifies gene expression networks driving differentiation and tumorigenesis in the human fallopian tube

The human fallopian tube harbors the cell of origin for the majority of high-grade serous "ovarian" cancers (HGSCs), but its cellular composition, particularly the epithelial component, is poorly characterized. We perform single-cell transcriptomic profiling of around 53,000 individual cells from 12 primary fallopian specimens to map their major cell types. We identify 10 epithelial subpopulations with diverse transcriptional programs. Based on transcriptional signatures, we reconstruct a trajectory whereby secretory cells differentiate into ciliated cells via a RUNX3^high intermediate. Computational deconvolution of advanced HGSCs identifies the "early secretory" population as a likely precursor state for the majority of HGSCs. Its signature comprises both epithelial and mesenchymal features and is enriched in mesenchymal-type HGSCs (p = 6.7 × 10^-27), a group known to have particularly poor prognoses. This cellular and molecular compendium of the human fallopian tube in cancer-free women is expected to advance our understanding of the earliest stages of fallopian epithelial neoplasia.

Exploring the clinical significance of serous tubal intraepithelial carcinoma associated with advanced high-grade serous ovarian cancer: A Memorial Sloan Kettering Team Ovary Study

OBJECTIVE

To evaluate the clinical significance and genomic associations of concurrent serous tubal intraepithelial carcinoma (STIC) with high-grade serous carcinoma (HGSC) of the ovary in women undergoing primary debulking surgery (PDS).

METHODS

All patients who underwent PDS for HGSC between 01/2015 and 12/2018 were captured in a prospectively maintained institutional database. Patients were categorized based on the presence or absence of concurrent STIC noted on final pathology. Demographic, perioperative, and outcomes data were collected, and groups were compared using standard statistical tests. Progression-free survival (PFS) and overall survival (OS) were evaluated using the Kaplan-Meier method. For comparison of differences in somatic alterations between the two cohorts, specimens were sequenced using MSK-IMPACT.

RESULTS

Of 306 eligible patients, 87 (28%) had a concurrent STIC lesion (+STIC) and 219 (72%) did not (no-STIC). Demographics and clinicopathological factors were similar between the two cohorts, except for a significantly higher median preoperative CA-125 level in the no-STIC group (423 U/mL vs. 321 U/mL; p=0.029). There were no significant differences in median PFS (22.7 months [95%CI: 18.9-28.4] vs. 27.7 months [95%CI: 25.5-30.5]; p=0.126) and 3- year OS rate (81% [95%CI: 70-88%] vs. 85% [95%CI: 78-90%]; p=0.392) between +STIC and no-STIC patients, respectively. Targeted DNA-sequencing via MSK-IMPACT showed a similar distribution of driver mutations or structural genetic alterations, and affected genetic signaling pathways were similar between the cohorts.

CONCLUSIONS

There were no identifiable clinical and genetic differences in patients with HGSC and concurrent STIC. These data suggest a comparable, if not identical, disease process.

Human spermbots for patient-representative 3D ovarian cancer cell treatment

Cellular micromotors are attractive for locally delivering high concentrations of drug, and targeting hard-to-reach disease sites such as cervical cancer and early ovarian cancer lesions by non-invasive means. Spermatozoa are highly efficient micromotors perfectly adapted to traveling up the female reproductive system. Indeed, bovine sperm-based micromotors have shown potential to carry drugs toward gynecological cancers. However, due to major differences in the molecular make-up of bovine and human sperm, a key translational bottleneck for bringing this technology closer to the clinic is to transfer this concept to human material. Here, we successfully load human sperm with Doxorubicin (DOX) and perform treatment of 3D cervical cancer and patient-representative ovarian cancer cell cultures, resulting in strong anticancer cell effects. Additionally, we define the subcellular localization of the chemotherapeutic drug within human sperm, using high-resolution optical microscopy. We also assess drug effects on sperm motility and viability over time, employing sperm samples from healthy donors as well as assisted reproduction patients. Finally, we demonstrate guidance and release of human drug-loaded sperm onto cancer tissues using magnetic microcaps, and show the sperm microcap loaded with a second anticancer drug, camptothecin (CPT), which unlike DOX is not suitable for directly loading into sperm due to its hydrophobic nature. This co-drug delivery approach opens up novel targeted combinatorial drug therapies for future applications.

Salpingectomy for the Risk Reduction of Ovarian Cancer: Is It Time for a Salpingectomy-alone Approach?

OBJECTIVE

To summarize published evidence supporting current strategies for the prevention of epithelial ovarian cancer in women with a genetic, elevated risk for the development of this disease, as well as the emerging data on the novel salpingectomy with delayed oophorectomy (SDO) strategy. Furthermore, we will explore whether salpingectomy alone is a viable risk-reducing strategy for these women. We will also discuss current national guidelines for risk-reducing surgery based on patients' individual genetic predisposition.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and the Cochrane Database, with a focus on randomized controlled trials and large prospective, observational studies.

METHODS OF STUDY SELECTION

The key search terms for our review included Medical Subject Headings: "salpingectomy," "ovarian cancer," and "risk-reducing surgery."

TABULATION, INTEGRATION, AND RESULTS

The fallopian tube is now well established as the site of origin for most ovarian cancers, particularly high-grade serous carcinomas. This finding has led to the development of new preventive surgical techniques, such as SDO, which may be associated with fewer side effects. However, until the results of ongoing trials are reported and the impact of SDO on ovarian cancer risk reduction is established, it should not be recommended outside of clinical trials, and bilateral salpingo-oophorectomy remains the treatment of choice for risk-reducing surgery, especially in women with a genetic, high risk for ovarian cancer.

CONCLUSION

The decision to undergo risk-reducing surgery among women with an elevated risk for ovarian cancer should be made after comprehensive consultation and individually based on genetic predisposition, childbearing status, and personal preference.

Increase of fallopian tube and decrease of ovarian carcinoma: fact or fake?

PURPOSE

Accurate disease classification is fundamental for the selection of the treatment approach, prognostication, selection of clinical trials and for research purposes in routine clinical practice. Extrauterine high-grade serous carcinoma (HG-SC) may arise from the ovary, the fallopian tube and rarely from the peritoneal surface epithelium. Regardless of its origin, the vast majority of patients with HG-SC share clinical symptoms, present with advanced stage disease and suffer from a poor prognosis. Recent data suggest that there is an increasing incidence of HG-SC arising from the fallopian tube.

METHODS

Data from the Clinical Cancer Registry of Leipzig of surgically treated non-uterine pelvic carcinomas were analyzed regarding their sites of origin. Depending on the histology, cases were separated into high-grade serous and non-high-grade serous tumors. Based on different approaches in the assessment of the site of origin, three distinct time periods were defined. The frequency of the specific sites of origin was compared to the different time periods and histologic subtypes.

RESULTS

The majority of cases (57.9%; 279/482) were high-grade serous carcinomas, 42.1% of the cases presented with endometrioid, clear cell or mucinous histology. Overall, a 1.7-fold decrease of carcinomas with ovarian origin, paralleled by a 10.3-fold increase of tubal carcinomas was noted between 2000 and 2019. Based on the histopathological subtype, there was a 2.1-fold decrease of ovarian and a 7.1-fold increase of tubal carcinomas in patients with HG-SC. In non-high-grade serous tumors, the frequency of the different sites of origin did not change. 83.7% of tumors with non-high-grade serous histology originated from the ovary, whereas 86.8% of the carcinomas with tubal origin were of high-grade serous histology.

CONCLUSION

The present and published data of non-uterine pelvic cancers may suggest an increase of tubal and decrease of ovarian carcinomas. However, there is rising morphologic and molecular evidence that non-uterine HG-SC actually arise from the fallopian tubes via its precursor STIC instead of from the ovary. This evidence has had an impact on the handling and reporting of non-uterine surgical specimens and its definition of the site assessment. In conclusion, the increasing frequency of tubal carcinomas and the associated decrease in ovarian cancer appears to be due to the reclassification of tumors previously classified as ovarian and greater emphasis on examining the resection specimens of non-uterine pelvic carcinomas.

Morphological and molecular heterogeneity of epithelial ovarian cancer: Therapeutic implications

Ovarian epithelial cancer (OEC) is the most lethal gynecologic malignancy. Despite current chemotherapeutic and surgical options, this high lethality can be attributed to multiple factors, including late-stage presentation. In order to optimize OEC treatment, it is important to highlight that it is composed of five main subtypes: high-grade serous ovarian carcinoma (HGSOC), low-grade serous ovarian carcinoma (LGSOC), endometrioid ovarian carcinoma (EOC), ovarian clear cell carcinoma (CCOC), and mucinous ovarian carcinoma (MOC). These subtypes differ in their precursor lesions, as well as in epidemiological, morphological, molecular and clinical features. OEC is one of the tumours in which most pathogenic germline mutations have been identified. Accordingly, up to 20% OC show alterations in BRCA1/2 genes, and also, although with a lower frequency, in other low penetrance genes associated with homologous recombination deficiency (HRD), mismatch repair genes (Lynch syndrome) and TP53. The most important prognostic factor is the 2014 FIGO staging, while older age is also associated with worse survival. HGSOC in all stages and CCC and MOC in advanced stages have the worse prognosis among histological types. Molecular markers have emerged as prognostic factors, particularly mutations in BRCA1/2, which are associated with a better outcome. Regarding treatment, whereas a proportion of HGSOC is sensible to platinum-based treatment and PARP inhibitors due to HRD, the rest of the histological types are relatively chemoresistant. New treatments based in specific molecular alterations are being tested in different histological types. In addition, immunotherapy could be an option, especially for EOC carrying mismatch repair deficiency or POLE mutations.

•

The five different histological types have different precursor lesions and epidemiological, morphological, genetic, epigenetic and clinical features.

•

Histological type is an important prognostic factor.

•

Drugs targeting homologous recombination deficiency have been approved for treatment.

•

The use of immunotherapy is limited due to lack of predictive biomarkers

The tubal epigenome - An emerging target for ovarian cancer

Ovarian cancer is the most lethal gynecologic malignancy in the United States. The mortality of this disease is primarily attributed to challenges in early detection and therapeutic resistance. Recent studies indicate that the majority of high-grade serous ovarian carcinomas (HGSCs) originate from aberrant fallopian tube epithelial (FTE) cells. This shift in thinking about ovarian cancer pathogenesis has been met with an effort to identify the early genetic and epigenetic changes that underlie the transformation of normal FTE cells and prompt them to migrate and colonize the ovary, ultimately giving rise to aggressive HGSC. While identification of these early changes is important for biomarker discovery, the emergence of epigenetic alterations in FTE chromatin may also provide new opportunities for early detection, prevention, and therapeutic intervention. Here we provide a comprehensive overview of the current knowledge regarding early epigenetic reprogramming that precedes HGSC tumor development, the way that these alterations affect both intrinsic and extrinsic tumor properties, and how the epigenome may be targeted to thwart HGSC tumorigenesis.

Prophylactic salpingectomy for the prevention of ovarian cancer: Who should we target?

Ovarian cancer is the most fatal gynecologic malignancy (50% 5-year survival) due to a typically advanced stage at diagnosis and a high rate of recurrence. Chemoprevention options are limited, and few interventions have been shown to reduce cancer risk or mortality. Emerging data support the model that fallopian tubes are the site of origin for a proportion of high-grade serous cancers. This implies that a subset of cancers may be prevented by removing the fallopian tubes while leaving the ovaries intact. Accordingly, there has been shift in clinical practice for average risk women; some now recommend removal of both the fallopian tubes only instead of tubal ligation for sterilization or at the time of benign gynecologic surgery. This has been termed opportunistic salpingectomy and represents a means of decreasing the burden of ovarian cancer by preventing cancers that arise in the fallopian tubes. There have been no detailed, prospective reports that have estimated ovarian cancer risk reduction with opportunistic salpingectomy, neither among women at baseline population risk nor among women at a high risk of developing the disease. The situation is complicated for women with a BRCA mutation-bilateral salpingo-oophorectomy is a proven means of risk reduction and salpingectomy alone is not the standard of care. Based on the existing data, salpingectomy alone should only be reserved for women with a lifetime risk of ovarian cancer of less than 5%.

Screening and Prevention for High-Grade Serous Carcinoma of the Ovary Based on Carcinogenesis-Fallopian Tube- and Ovarian-Derived Tumors and Incessant Retrograde Bleeding

High-grade serous carcinoma (HGSC) is the most common and lethal subtype of ovarian carcinoma. Many HGSCs are now believed to originate in the fallopian tube epithelium; ovarian surface epithelium is another possible origin. Thus, current screening methods, i.e., ultrasonography and serum CA-125 measurements, have a limitation in their early detection. Recently, circulating biomarkers, such as tumor DNA, autoantibody, and microRNA, have been investigated to detect HGSCs. As cancer cells in the fallopian tube flow into the endometrial cavity, the detection of exfoliated cells, tumor DNA, and proteome from samples obtained from the endometrial cavity or the cervix may be useful. The risk of ovarian serous carcinoma is affected by the use of oral contraceptive and menopausal hormone therapy (MHT). MHT regimens causing endometrial bleeding increase serous carcinoma risk, hence, incessant retrograde bleeding from the endometrial cavity into the Douglas pouch appears to play an important role in high-grade serous carcinogenesis. In this review, we provide an overview of current and novel screening methods and prevention approaches for ovarian and fallopian tube HGSC.

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.

A detailed morphological and immunohistochemical comparison of primary endometrial and tubo-ovarian high-grade serous carcinomas and their corresponding omental metastases

Increasingly, high-grade serous carcinomas (HGSCs) of fallopian tube/ovarian origin are managed initially with neoadjuvant chemotherapy (NACT) and pre-treatment diagnosis is often based upon relatively limited core biopsy and/or cytology specimens. Endometrial HGSC can also present with adnexal and peritoneal metastasis, thus mimicking a primary tubo-ovarian neoplasm, but the role of NACT in these cases is less established. Immunohistochemistry has been considered useful in this distinction but with a wide range of reported findings in the literature. In this study we have examined tumour growth patterns and the expression p16, Ki-67, WT1, PAX2, HER2, ER-α, ER-β, PR, and BAF250a in 18 tubo-ovarian and 14 endometrial HGSCs, comparing the findings in primary and omental sites. Metastatic tubo-ovarian carcinomas demonstrated significantly more varied architectural patterns than metastatic endometrial HGSCs (median 2.5 versus 1). None of the immunohistochemical markers proved completely reliable but only endometrial HGSC were WT1 negative (7/14 metastatic tumours) or demonstrated over-expression of HER2 (2/14 cases). Micropapillary tumour elements more often showed retained PAX2 and WT1 expression, low Ki-67 labelling, and (in endometrial tumours) PR staining. Diverse architectural patterns suggest tubo-ovarian origin in a metastatic HGSC. Immunohistochemical results should be cautiously interpreted, particularly in small specimens.

Ovarian High-Grade Serous Carcinoma: Assessing Pathology for Site of Origin, Staging and Post-neoadjuvant Chemotherapy Changes

High-grade serous (HGSC) stands apart from the other ovarian cancer histotypes in being the most frequent, in occurring as part of a genetic predisposition in a significant proportion of cases, and in having the poorest clinical outcomes. Although the pathologic diagnosis of HGSC is now made with high accuracy, there remain areas of disagreement regarding viewpoints on tissue site of origin and designation of primary site, with impact on staging in low-stage cases, as well as difficulties in reproducible and clinically relevant reporting of HGSC in specimens taken after neoadjuvant chemotherapy. These areas are discussed in the current article.

Interventions to improve psychosocial well-being in female BRCA-mutation carriers following risk-reducing surgery

BACKGROUND

Women who carry a pathogenic mutation in either a BRCA1 DNA repair associated or BRCA2 DNA repair associated (BRCA1 or BRCA2) gene have a high lifetime risk of developing breast and tubo-ovarian cancer. To manage this risk women may choose to undergo risk-reducing surgery to remove breast tissue, ovaries, and fallopian tubes. Surgery should increase survival, but can impact women's lives adversely at the psychological and psychosexual levels. Interventions to facilitate psychological adjustment and improve quality of life post risk-reducing surgery are needed.

OBJECTIVES

To examine psychosocial interventions in female BRCA carriers who have undergone risk-reducing surgery and to evaluate the effectiveness of such interventions on psychological adjustment and quality of life.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and Embase via Ovid, CINAHL, PsycINFO, Web of Science up to April 2019 and Scopus up to January 2018. We also handsearched abstracts of scientific meetings and other relevant publications.

SELECTION CRITERIA

We included randomised controlled trials (RCT), non-randomised studies (NRS), prospective and retrospective cohort studies and interventional studies using baseline and postintervention analyses in female BRCA carriers who have undergone risk-reducing surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility studies for inclusion in the review. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We screened 4956 records from the searches, selecting 34 unique studies for full-text scrutiny, of which two met the inclusion criteria: one RCT and one NRS. The included studies assessed 113 female BRCA carriers who had risk-reducing surgery, but there was attrition, and outcome data were not available for all participants at final study assessments. We assessed the RCT as at a high risk of bias whilst the NRS did not have a control group. Our GRADE assessment of the studies was very low-certainty due to the paucity of data and methodological shortcomings of the studies. The primary outcome of quality of life was only measured in the RCT and that was specific to the menopause. Both studies reported on psychological distress and sexual function. Neither study measured body image, perhaps because this is most often associated with risk-reducing mastectomy rather than oophorectomy.The RCT (66 participants recruited with 48 followed to 12 months) assessed the short- and long-term effects of an eight-week mindfulness-based stress reduction (MBSR) training programme on quality of life, sexual functioning, and sexual distress in female BRCA carriers (n = 34) in a specialised family cancer clinic in the Netherlands compared to female BRCA carriers (n = 32) who received usual care. Measurements on the Menopause-Specific Quality of Life Questionnaire (MENQOL) showed some improvement at 3 and 12 months compared to the usual care group. At 3 months the mean MENQOL scores were 3.5 (95% confidence interval (CI) 3.0 to 3.9) and 3.8 (95% CI 3.3 to 4.2) for the MBSR and usual care groups respectively, whilst at 12 months the corresponding values were 3.6 (95% CI 3.1 to 4.0) and 3.9 (95% CI 3.5 to 4.4) (1 study; 48 participants followed up at 12 months). However, these results should be interpreted with caution due to the very low-certainty of the evidence, where a lower score is better. Other outcome measures on the Female Sexual Function Index and the Female Sexual Distress Scale showed no significant differences between the two groups. Our GRADE assessment of the evidence was very low-certainty due to the lack of blinding of participants and personnel, attrition bias and self-selection (as only one-third of eligible women chose to participate in the study) and serious imprecision due to the small sample size and wide 95% CI.The NRS comprised 37 female BRCA carriers selected from three Boston-area hospitals who had undergone a novel sexual health intervention following risk-reducing salpingo-oophorectomy (RRSO) without a history of tubo-ovarian cancer. The intervention consisted of targeted sexual-health education, body awareness and relaxation training, and mindfulness-based cognitive therapy strategies, followed by two sessions of tailored telephone counselling. This was a single-arm study without a control group. Our GRADE assessment of the evidence was very low-certainty, and as there was no comparison group in the included study, we could not estimate a relative effect. The study reported change in psychosexual adjustment from baseline to postintervention (median 2.3 months) using measures of Female Sexual Function Index (n = 34), which yielded change with a mean of 3.91, standard deviation (SD) 9.12, P = 0.018 (1 study, 34 participants; very low-certainty evidence). The Brief Symptom Inventory, Global Severity Index yielded a mean change of 3.92, SD 5.94, P < 0.001. The Sexual Self-Efficacy Scale yielded change with a mean of 12.14, SD 20.56, P < 0.001. The Sexual Knowledge Scale reported mean change of 1.08, SD 1.50, P < 0.001 (n = 36). Participant satisfaction was measured by questionnaire, and 100% participants reported that they enjoyed taking part in the psychoeducation group and felt "certain" or "very certain" that they had learned new skills to help them cope with the sexual side effects of RRSO.

AUTHORS' CONCLUSIONS

The effect of psychosocial interventions on quality of life and emotional well-being in female BRCA carriers who undergo risk-reducing surgery is uncertain given the very low methodological quality in the two studies included in the review. The absence of such interventions highlights the need for partnership between researchers and clinicians in this specific area to take forward the patient-reported outcomes and develop interventions to address the psychosocial issues related to risk-reducing surgery in female BRCA carriers, particularly in this new era of genomics, where testing may become more mainstream and many more women are identified as gene carriers.

Hysterectomy with opportunistic salpingectomy versus hysterectomy alone

BACKGROUND

Ovarian cancer has the highest mortality rate of all gynaecological malignancies with an overall five-year survival rate of 30% to 40%. In the past two decades it has become apparent and more commonly accepted that a majority of ovarian cancers originate in the fallopian tube epithelium and not from the ovary itself. This paradigm shift introduced new possibilities for ovarian cancer prevention. Salpingectomy during a hysterectomy for benign gynaecological indications (also known as opportunistic salpingectomy) might reduce the overall incidence of ovarian cancer. Aside from efficacy, safety is of utmost importance, especially due to the preventive nature of opportunistic salpingectomy. Most important are safety in the form of surgical adverse events and postoperative hormonal status. Therefore, we compared the benefits and risks of hysterectomy with opportunistic salpingectomy to hysterectomy without opportunistic salpingectomy.

OBJECTIVES

To assess the effect and safety of hysterectomy with opportunistic salpingectomy versus hysterectomy without salpingectomy for ovarian cancer prevention in women undergoing hysterectomy for benign gynaecological indications; outcomes of interest include the incidence of epithelial ovarian cancer, surgery-related adverse events and postoperative ovarian reserve.

SEARCH METHODS

The Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and two clinical trial registers were searched in January 2019 together with reference checking and contact with study authors.

SELECTION CRITERIA

We intended to include both randomised controlled trials (RCTs) and non-RCTs that compared ovarian cancer incidence after hysterectomy with opportunistic salpingectomy to hysterectomy without opportunistic salpingectomy in women undergoing hysterectomy for benign gynaecological indications. For assessment of surgical and hormonal safety, we included RCTs that compared hysterectomy with opportunistic salpingectomy to hysterectomy without opportunistic salpingectomy in women undergoing hysterectomy for benign gynaecological indications.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. The primary review outcomes were ovarian cancer incidence, intraoperative and short-term postoperative complication rate and postoperative hormonal status. Secondary outcomes were total surgical time, estimated blood loss, conversion rate to open surgery (applicable only to laparoscopic and vaginal approaches), duration of hospital admission, menopause-related symptoms and quality of life.

MAIN RESULTS

We included seven RCTs (350 women analysed). The evidence was of very low to low quality: the main limitations being a low number of included women and surgery-related adverse events, substantial loss to follow-up and a large variety in outcome measures and timing of measurements.No studies reported ovarian cancer incidence after hysterectomy with opportunistic salpingectomy compared to hysterectomy without opportunistic salpingectomy in women undergoing hysterectomy for benign gynaecological indications. For surgery-related adverse events, there were insufficient data to assess whether there was any difference in both intraoperative (odds ratio (OR) 0.66, 95% confidence interval (CI) 0.11 to 3.94; 5 studies, 286 participants; very low-quality evidence) and short-term postoperative (OR 0.13, 95% CI 0.01 to 2.14; 3 studies, 152 participants; very low-quality evidence) complication rates between hysterectomy with opportunistic salpingectomy and hysterectomy without opportunistic salpingectomy because the number of surgery-related adverse events was very low. For postoperative hormonal status, the results were compatible with no difference, or with a reduction in anti-Müllerian hormone (AMH) that would not be clinically relevant (mean difference (MD) -0.94, 95% CI -1.89 to 0.01; I² = 0%; 5 studies, 283 participants; low-quality evidence). A reduction in AMH would be unfavourable, but due to wide CIs, the postoperative change in AMH can still vary from a substantial decrease to even a slight increase.

AUTHORS' CONCLUSIONS

There were no eligible studies reporting on one of our primary outcomes - the incidence of ovarian cancer specifically after hysterectomy with or without opportunistic salpingectomy. However, outside the scope of this review there is a growing body of evidence for the effectiveness of opportunistic salpingectomy itself during other interventions or as a sterilisation technique, strongly suggesting a protective effect. In our meta-analyses, we found insufficient data to assess whether there was any difference in surgical adverse events, with a very low number of events in women undergoing hysterectomy with and without opportunistic salpingectomy. For postoperative hormonal status we found no evidence of a difference between the groups. The maximum difference in time to menopause, calculated from the lower limit of the 95% CI and the natural average AMH decline, would be approximately 20 months, which we consider to be not clinically relevant. However, the results should be interpreted with caution and even more so in very young women for whom a difference in postoperative hormonal status is potentially more clinically relevant. Therefore, there is a need for research on the long-term effects of opportunistic salpingectomy during hysterectomy, particularly in younger women, as results are currently limited to six months postoperatively. This limit is especially important as AMH, the most frequently used marker for ovarian reserve, recovers over the course of several months following an initial sharp decline after surgery. In light of the available evidence, addition of opportunistic salpingectomy should be discussed with each woman undergoing a hysterectomy for benign indication, with provision of a clear overview of benefits and risks.

Reported Incidence and Survival of Fallopian Tube Carcinomas: A Population-Based Analysis From the North American Association of Central Cancer Registries

Background

Recognition that serous tubal intraepithelial carcinoma (STIC) may represent the first manifestation of many high-grade cancers that were once considered ovarian primary tumors has led to changes in diagnostic practices that could dramatically increase the reporting of tubal carcinomas in US population-based cancer registries. Further, increased detection of early-stage tubal carcinomas through increased recognition coupled with meticulous pathology processing protocols raises important unanswered questions about the clinical behavior of such lesions, which can only be answered using large data sets. However, rates of tubal carcinomas have not been recently analyzed. Accordingly, we analyzed population-based incidence and survival data for fallopian tube carcinoma in situ (CIS; an imperfect surrogate of STIC), tubal carcinomas, and for comparison, ovarian carcinomas, in the North American Association of Central Cancer Registries (NAACCR) registries.

Methods

Total counts, standardized incidence rates, and stage-specific survival were computed using 30 NAACCR registries (1999-2012). Temporal incidence rate patterns were analyzed by joinpoint regression with estimates of annual percentage change (APC). All statistical tests were two-sided.

Results

Fallopian tube CIS incidence rates were stable from 1999 to 2002, then increased from 2002 to 2012 (APC = 16.2%, 95% confidence interval [CI] = 10.9% to 21.7%, P < .001). Rates of early- and late-stage tubal carcinomas showed similar patterns, whereas high-grade serous ovarian carcinoma rates were relatively stable. Five-year cause-specific survival was 97.9% (95% CI = 93.7% to 99.3%) for tubal CIS and 83.2% (95% CI = 77.3% to 87.7%) for early-stage high-grade serous tubal carcinoma.

Conclusions

Reporting of tubal CIS and tubal carcinoma have increased in recent years, likely reflecting changes in pathology processing of specimens and diagnosis. Developing standardized reporting for tubal neoplasms is needed to enable analysis of outcomes for these comparatively uncommon but increasingly recognized tumors.

Fallopian Tube Carcinoma

Primary fallopian tube carcinoma is a rare and difficult to cure disease. It is often grouped under the epithelial ovarian cancer umbrella, together with primary ovarian and peritoneal carcinomas. More recent evidence has suggested that epithelial ovarian cancers originate from a fallopian tube precursor. The mainstay of treatment is surgical cytoreduction and platinum-based chemotherapy. There is much debate over the best timing for surgery and the best approach to delivering the chemotherapy: traditional intravenous once every 3 weeks regimen, versus intraperitoneal, versus dose-dense intravenous regimens. Although these debates continue, novel targeted therapies, including bevacizumab and poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors, have emerged. PARP inhibitors are particularly efficacious in patients with BRCA1/2 gene mutations, and their use has been shown to prolong patient survival. This article reviews the pathologic etiology; describes the heredity, treatment challenges, and controversies; and summarizes novel therapies in primary fallopian tube carcinoma.

Increased expression of neurotensin in high grade serous ovarian carcinoma with evidence of serous tubal intraepithelial carcinoma

High grade serous ovarian carcinoma (HGSC) without identifiable serous tubal intraepithelial carcinoma (STIC) within the fallopian tube (FT) occurs in approximately 50% of patients. The objective of this study was to use a multisite tumor sampling approach to study HGSC with and without STIC. RNAseq analysis of HGSC samples collected from multiple sites e.g. ovary, FT and peritoneum, revealed moderate levels of intrapatient heterogeneity in gene expression that could influence molecular profiles. Mixed‐model ANOVA analysis of gene expression in tumor samples from patients with multiple tumor sites (n = 13) and patients with a single site tumor sample (n = 11) to compare HGSC‐STIC to HGSC‐NOSTIC identified neurotensin (NTS) as significantly higher (> two‐fold change, False Discovery Rate (FDR) < 0.10) in HGSC‐STIC. This data was validated using publicly available RNA‐Seq datasets. Concordance between higher NTS gene expression and NTS peptide levels in HGSC‐STIC samples was demonstrated by immunohistochemistry. To determine the role of NTS in HGSC, five ovarian cancer (OvCa) cell lines were screened for expression of NTS and its receptors, NTSR1 and NTSR3. Increased expression of NTS and NSTR1 was observed in several of the OvCa cells, whereas the NTSR3 receptor was lower in all OvCa cells, compared to immortalized FT epithelial cells. Treatment with NTSR1 inhibitor (SR48692) decreased cell proliferation, but increased cell migration in OvCa cells. The effects of SR48692 were receptor mediated, since transient RNAi knockdown of NTSR1 mimicked the migratory effects and knockdown of NTSR3 mimicked the anti‐proliferative effects. Further, knockdown of NTSR1 or NTSR3 was associated with acquisition of distinct morphological phenotypes, epithelial or mesenchymal, respectively. Taken together, our results reveal a difference in a biologically active pathway between HGSC with and without STIC. Furthermore, we identify neurotensin signaling as an important pathway involved in cell proliferation and epithelial–mesenchymal transition in HGSC‐STIC which warrants further study as a potential therapeutic target. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

ESMO-ESGO consensus conference recommendations on ovarian cancer: pathology and molecular biology, early and advanced stages, borderline tumours and recurrent disease

The development of guidelines is one of the core activities of the European Society for Medical Oncology (ESMO) and European Society of Gynaecologial Oncology (ESGO), as part of the mission of both societies to improve the quality of care for patients with cancer across Europe. ESMO and ESGO jointly developed clinically relevant and evidence-based recommendations in several selected areas in order to improve the quality of care for women with ovarian cancer. The ESMO-ESGO consensus conference on ovarian cancer was held on April 12-14, 2018 in Milan, Italy, and comprised a multidisciplinary panel of 40 leading experts in the management of ovarian cancer. Before the conference, the expert panel worked on five clinically relevant questions regarding ovarian cancer relating to each of the following four areas: pathology and molecular biology, early-stage and borderline tumours, advanced stage disease and recurrent disease. Relevant scientific literature, as identified using a systematic search, was reviewed in advance. During the consensus conference, the panel developed recommendations for each specific question and a consensus was reached. The recommendations presented here are thus based on the best available evidence and expert agreement. This article presents the recommendations of this ESMO-ESGO consensus conference, together with a summary of evidence supporting each recommendation.

ESMO-ESGO consensus conference recommendations on ovarian cancer: pathology and molecular biology, early and advanced stages, borderline tumours and recurrent disease†

The development of guidelines recommendations is one of the core activities of the European Society for Medical Oncology (ESMO) and European Society of Gynaecologial Oncology (ESGO), as part of the mission of both societies to improve the quality of care for patients with cancer across Europe. ESMO and ESGO jointly developed clinically relevant and evidence-based recommendations in several selected areas in order to improve the quality of care for women with ovarian cancer. The ESMO-ESGO consensus conference on ovarian cancer was held on 12-14 April 2018 in Milan, Italy, and comprised a multidisciplinary panel of 40 leading experts in the management of ovarian cancer. Before the conference, the expert panel worked on five clinically relevant questions regarding ovarian cancer relating to each of the following four areas: pathology and molecular biology, early-stage and borderline tumours, advanced stage disease and recurrent disease. Relevant scientific literature, as identified using a systematic search, was reviewed in advance. During the consensus conference, the panel developed recommendations for each specific question and a consensus was reached. The recommendations presented here are thus based on the best available evidence and expert agreement. This article presents the recommendations of this ESMO-ESGO consensus conference, together with a summary of evidence supporting each recommendation.

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.

An evolving story of the metastatic voyage of ovarian cancer cells: cellular and molecular orchestration of the adipose-rich metastatic microenvironment

Metastasis is a complex multistep process that involves critical interactions between cancer cells and a variety of stromal components in the tumor microenvironment, which profoundly influence the different aspects of the metastatic cascade and organ tropism of disseminating cancer cells. Ovarian cancer is the most lethal gynecological malignancy and is characterized by peritoneal disseminated metastasis. Evidence has demonstrated that ovarian cancer possesses specific metastatic tropism for the adipose-rich omentum, which has a pivotal role in the creation of the metastatic tumor microenvironment in the intraperitoneal cavity. Considering the distinct biology of ovarian cancer metastasis, the elucidation of the cellular and molecular mechanisms underlying the reciprocal interplay between ovarian cancer cells and surrounding stromal cell types in the adipose-rich metastatic microenvironment will provide further insights into the development of novel therapeutic approaches for patients with advanced ovarian cancer. Herein, we review the biological mechanisms that regulate the highly orchestrated crosstalk between ovarian cancer cells and various cancer-associated stromal cells in the metastatic tumor microenvironment with regard to the omentum by illustrating how different stromal cells concertedly contribute to the development of ovarian cancer metastasis and metastatic tropism for the omentum.

Population Frequency of Serous Tubal Intraepithelial Carcinoma (STIC) in Clinical Practice Using SEE-Fim Protocol

Frequent detection of serous tubal intraepithelial carcinoma (STIC) among BRCA1/2 mutation carriers undergoing risk-reducing surgery prompted the hypothesis that many adnexal high-grade serous carcinomas (HGSCs) arise from the fallopian tube, rather than the ovary, as supposed. The changing paradigm has important implications for HGSC prevention. Most data related to the frequency of STIC are derived from case series and estimates vary widely. Therefore, we analyzed population-based data from 10 523 surgeries including salpingectomy (Jan 2014-Dec 2016) that were examined using the "Sectioning and Extensively Examining the Fimbria" protocol, which optimizes STIC detection. Overall, STIC was detected in 40 (0.38%) specimens, including 32 diagnosed with concurrent gynecologic cancer. STIC was detected in 8 (<0.01%) of 9392 cases with benign diagnoses. We conclude that the relative rarity of STIC diagnoses in routine pathology practice has critical implications for research aiming to elucidate the pathogenesis of HGSC and developing prevention strategies.

The fallopian tube, "precursor escape" and narrowing the knowledge gap to the origins of high-grade serous carcinoma

Most ovarian carcinomas are high-grade serous carcinomas (HGSC) that contain TP53 mutations, present at advanced stage, and eventually become resistant to chemotherapy. The rapid evolution of this disease has been attributed to an origin in the distal fallopian tube, in the form of serous tubal intraepithelial carcinomas (STICs). This has led to a disease model where malignancy develops first in the tube and spreads to the peritoneum or regional lymph nodes. However, although most early or incidentally discovered HGSCs manifest in the tube with STICs, many advanced HGSCs are not accompanied by a malignancy in the fimbria. To resolve this paradox, the focus has shifted to earlier, premalignant serous proliferations (ESPs) in the tubes, which lack the cytomorphologic features of malignancy but contain TP53 mutations. These have been termed p53 signatures or serous tubal intraepithelial lesions (STILs). Although they have not been presumed to have cancer-causing potential by themselves, some ESPs have recently been shown to share identical TP53 mutations with concurrent HGSCs, indicating a shared lineage between these early mucosal changes and metastatic malignancy. This discovery supports a paradigm by which HGSCs can emerge not only from STICs but also from exfoliated precursor cells (precursor escape) that eventually undergo malignant transformation within the peritoneal cavity. This paradigm unifies both localized and widespread HGSCs to a visible pre-existing cellular alteration in the tubal epithelium, and highlights a consistent and necessary biologic event (TP53 mutation) rarely encountered in the ovary or secondary Mullerian system. This dual pathway to HGSCs underscores the subtle nature of many serous cancer origins in the tube, explains contrasting clinico-pathologic presentations, and explains why, until recently, the fallopian tube was unappreciated as the principal origin of HGSCs. Moreover, it highlights additional challenges faced in preventing or intercepting HGSCs at a curable stage.

Back to the Future? The Fallopian Tube, Precursor Escape and a Dualistic Model of High-Grade Serous Carcinogenesis

Beginning with the discovery of the BRCA-associated ovarian cancer susceptibility genes and subsequent detailed examination of risk-reducing salpingo-oophorectomy (RRSO) specimens, a new paradigm of ovarian carcinogenesis has unfolded with attention to the distal fallopian tube. The primary focus has been an early cancer or neoplasm in the fallopian tube which is seen in virtually all incidentally discovered high-grade serous cancers in asymptomatic women. This high-frequency of tubal involvement in early serous neoplasm (usually in the form of serous tubal intraepithelial carcinoma—STIC) has galvanized attention to this organ as a primary source of this disease. However, an enduring mystery has been the relatively low frequency of STIC in the fallopian tubes of women with advanced malignancy. This paradox, a high frequency of tubal involvement early on and a low frequency of involvement later in the disease process, has spurred interest in other potential sources, such as the ovarian surface epithelium or cortical inclusions and the secondary Mullerian system. However, because essentially all high-grade serous carcinomas are linked by TP53 mutations, and because fallopian tubes frequently contain early serous proliferations (ESPs) with these mutations, attention has turned to the possibility that the nonmalignant but TP53 mutated tubal epithelium could be responsible for an eventual malignancy. Recent data have shown evidence of a lineage continuity between ESPs and concurrent serous carcinomas prompting the concept of “precursor escape”. This creates a second component of the paradigm by which cells from early precursors are shed from the tube and undergo subsequent malignant transformation, emerging suddenly as widespread intraperitoneal malignancy. This dualistic model thus provides a unique pathway by which the future outcome (wide spread high-grade serous carcinomas—HGSC) is ultimately explained by going back in time to an early serous proliferation. This paradigm also brings the peritoneal cavity into focus, raising new questions about the potential co-variables or exposures that might facilitate the occasional malignant transformation of an ESP in the peritoneal cavity or on the peritoneal surface.

Cell Origins of High-Grade Serous Ovarian Cancer

High-grade serous ovarian cancer, also known as high-grade serous carcinoma (HGSC), is the most common and deadliest type of ovarian cancer. HGSC appears to arise from the ovary, fallopian tube, or peritoneum. As most HGSC cases present with widespread peritoneal metastases, it is often not clear where HGSC truly originates. Traditionally, the ovarian surface epithelium (OSE) was long believed to be the origin of HGSC. Since the late 1990s, the fallopian tube epithelium has emerged as a potential primary origin of HGSC. Particularly, serous tubal intraepithelial carcinoma (STIC), a noninvasive tumor lesion formed preferentially in the distal fallopian tube epithelium, was proposed as a precursor for HGSC. It was hypothesized that STIC lesions would progress, over time, to malignant and metastatic HGSC, arising from the fallopian tube or after implanting on the ovary or peritoneum. Many clinical studies and several mouse models support the fallopian tube STIC origin of HGSC. Current evidence indicates that STIC may serve as a precursor for HGSC in high-risk women carrying germline BRCA1 or 2 mutations. Yet not all STIC lesions appear to progress to clinical HGSCs, nor would all HGSCs arise from STIC lesions, even in high-risk women. Moreover, the clinical importance of STIC remains less clear in women in the general population, in which 85–90% of all HGSCs arise. Recently, increasing attention has been brought to the possibility that many potential precursor or premalignant lesions, though composed of microscopically—and genetically—cancerous cells, do not advance to malignant tumors or lethal malignancies. Hence, rigorous causal evidence would be crucial to establish that STIC is a bona fide premalignant lesion for metastatic HGSC. While not all STICs may transform into malignant tumors, these lesions are clearly associated with increased risk for HGSC. Identification of the molecular characteristics of STICs that predict their malignant potential and clinical behavior would bolster the clinical importance of STIC. Also, as STIC lesions alone cannot account for all HGSCs, other potential cellular origins of HGSC need to be investigated. The fallopian tube stroma in mice, for instance, has been shown to be capable of giving rise to metastatic HGSC, which faithfully recapitulates the clinical behavior and molecular aspect of human HGSC. Elucidating the precise cell(s) of origin of HGSC will be critical for improving the early detection and prevention of ovarian cancer, ultimately reducing ovarian cancer mortality.

Evidence for lineage continuity between early serous proliferations (ESPs) in the Fallopian tube and disseminated high-grade serous carcinomas

The distal Fallopian tube is a site of origin for many 'ovarian' high-grade serous carcinomas (HGSCs) with intraepithelial carcinomas (STICs) that share identical TP53 mutations with metastatic tumors. TP53 mutation-positive early serous proliferations (ESPs) comprise a spectrum including p53 signatures and serous tubal intraepithelial lesions (STILs) and are not considered malignant; however, ESPs are often the only abnormality found in Fallopian tubes of women with metastatic HGSC. The purpose of this study was to determine if a relationship exists between isolated ESPs and concurrent metastatic HGSCs in the absence of STIC. Fallopian tubes from 32 HGSCs without a co-existing STIC/HGSC in the endosalpinx were exhaustively sectioned. The presence of either STIC/HGSC or ESP in the endosalpinx was documented and DNA from tissues containing ESPs, concurrent HGSC, and control epithelia were interrogated for TP53 mutations by targeted amplicon-based sequencing with average coverage reads >4000 across DNA replicate samples. Serial sectioning revealed a previously unrecognized STIC/HGSC in 3 of 32 (9.3%) and ESPs in 13 (40.6%). Twelve contained TP53 mutations. Nine (75%) shared identical TP53 mutations with concurrent HGSCs, four at high (≥ 5%) and five at low (< 5%) allele frequency. All control epithelia were TP53 mutation-negative. This study, for the first time, indicates lineage identity between ESPs in the distal tube and some metastatic HGSCs via a shared site-specific TP53 mutation. It supports a novel serous carcinogenic sequence in which an ESP could eventually culminate in a metastatic serous cancer via 'precursor escape' and would explain the apparent sudden onset of cancers without co-existing STICs. This paradigm for serous cancer development underscores the likelihood that multiple precursor types in the Fallopian tube contribute to serous cancer development with implications for the evolution, pathologic classification, and prevention of this lethal malignancy. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Surgical prevention strategies in ovarian cancer

Given the current lack of effective screening for ovarian cancer, surgical removal of at-risk tissue is the most successful strategy to decrease risk of cancer development. However, the optimal timing of surgery and tissues to remove, as well as the appropriate patients to undergo preventive procedures are poorly understood. In this review, we first discuss the origin and precursors of ovarian epithelial carcinomas, focusing on high-grade serous carcinomas and endometriosis-associated carcinomas, which cause the majority of the mortality and incidence of ovarian cancer. In addition, we summarize the implications of current understanding of specific pathogenic origins for surgical prevention and remaining gaps in knowledge. Secondly, we review evidence from the epidemiologic literature on the associations of various surgical prevention strategies, including endometriosis excision, tubal procedures, and bilateral salpingo-oophorectomy, with risk of future ovarian cancer development, as well as the short- and long-term consequences of these strategies on women's health and quality and life. We conclude with recommendations for surgical prevention in women with high-risk genetic mutations and average-risk women, and a brief discussion of ongoing research that will help clarify optimal surgical approaches that balance risk-reduction with maintenance of women's quality of life.

Processing of fallopian tube, ovary, and endometrial surgical pathology specimens: A survey of U.S. laboratory practices

OBJECTIVE

Many high-grade serous carcinomas initiate in fallopian tubes as serous tubal intraepithelial carcinoma (STIC), a microscopic lesion identified with specimen processing according to the Sectioning and Extensive Examination of the Fimbria protocol (SEE-Fim). Given that the tubal origin of these cancers was recently recognized, we conducted a survey of pathology practices to assess processing protocols that are applied to gynecologic surgical pathology specimens in clinical contexts in which finding STIC might have different implications.

METHODS

We distributed a survey electronically to the American Society for Clinical Pathology list-serve to determine practice patterns and compared results between practice types by chi-square (χ2) tests for categorical variables. Free text comments were qualitatively reviewed.

RESULTS

Survey responses were received from 159 laboratories (72 academic, 87 non-academic), which reported diverse specimen volumes and percentage of gynecologic samples. Overall, 74.1% of laboratories reported performing SEE-Fim for risk-reducing surgical specimens (82.5% academic versus 65.7% non-academic, p < 0.05). In specimens from surgery for benign indications in which initial microscopic sections showed an unanticipated suspicious finding, 75.9% of laboratories reported using SEE-Fim to process the remainder of the specimen (94.8% academic versus 76.4% non-academic, p < 0.01), and 84.6% submitted the entire fimbriae.

CONCLUSIONS

Changes in the theories of pathogenesis of high-grade serous carcinoma have led to implementation of pathology specimen processing protocols that include detailed analysis of the fallopian tubes. These results have implications for interpreting trends in cancer incidence data and considering the feasibility of developing a bank of gynecologic tissues containing STIC or early cancer precursors.

Opportunistic salpingectomy at benign gynecological surgery for reducing ovarian cancer risk: a 10-year single centre experience from China and a literature review

Current evidences indicate that the fallopian tube plays a major role in the pathogenesis of epithelial ovarian cancer (EOC). Salpingectomy represents a novel and potentially effective risk-reducing option. In this study, there were 1822 patients diagnosed and treated for EOC or primary peritoneal cancer (PPC) at Department of Gynecologic Oncology, Tianjin Medical University Cancer Institute and Hospital from January 1, 2007 to April 30, 2017. Among them, 198 patients with a history of gynecological surgery because of benign diseases were enrolled to analyze further. Using 1:2 case-control study, we found that the incidence of EOC was significantly decreased in the population with salpingectomy, compared to women with fallopian tube reserved (P<0.05). At the same period, there were 4339 patients receiving opportunistic salpingectomy in our centre because of benign gynecological diseases. The results showed the rate of bilateral salpingectomy was annually increased from 2007 to 2017 (22.02% to 60.22%), which showed approximately threefold increase in a decade. In general, factors affecting the rate of salpingectomy included age, child number, menopause or not, marital status, educational status, income status, and with or without family history of tumor. Therefore, based on ten years experiences from our centre, it is recommended that physician should discuss with appropriate patients to perform opportunistic bilateral salpingectomy at the time of receiving benign gynecological surgery for preventing ovarian cancer. Moreover, the prospective, large scale and multi-centre studies to evaluate the safety and efficacy of salpingectomy as a preventive strategy for ovarian cancer warrant to conduct in the future.

Persistence of fimbrial tissue on the ovarian surface after salpingectomy

BACKGROUND

Salpingectomy is recommended as a risk-reducing strategy for epithelial tubo-ovarian cancer. The gold standard procedure is complete tubal excision.

OBJECTIVE

The purpose of this study was to assess the presence of residual fimbrial/tubal tissue on ovarian surfaces after salpingectomy.

STUDY DESIGN

Prospective analysis of patients who underwent salpingo-oophorectomy with or without hysterectomy for benign indications, early cervical cancer, or low-risk endometrial cancer at a UK National Health Service Trust. Salpingectomy with or without hysterectomy was performed initially, followed by oophorectomy within the same operation. Separately retrieved tubes and ovaries were sectioned serially and examined completely histologically. The main outcome measure was histologically identified fimbrial/ tubal tissue on ovarian surface. Chi-square/Fisher's exact tests were used to evaluate categoric variables.

RESULTS

Twenty-five consecutive cases (mean age, 54.8 ± 5.0 years) that comprised 41 adnexae (unilateral, 9; bilateral, 16) were analyzed. Seventeen (68.0%), 5 (20.0%), and 3 (12.0%) procedures were performed by consultant gynecologists, subspecialty/specialist trainees, and consultant gynecologic oncologists, respectively. Twelve of 25 procedures (48.0%) were laparoscopic, and 13 of 25 procedures (52.0%) involved laparotomy. Four of 25 patients (16.0%; 95% confidence interval, 4.5-36.1%) or 4 of 41 adnexae (9.8%; 95% confidence interval, 2.7-23.1%) showed residual microscopic fimbrial tissue on the ovarian surface. Tubes/ovaries were free of adhesions in 23 cases. Two cases had dense adnexal adhesions, but neither had residual fimbrial tissue on the ovary. Residual fimbrial tissue was not associated significantly with surgical route or experience (consultant, 3/20 [15%]; trainee, 1/5 [20%]; P=1.0).

CONCLUSION

Residual fimbrial tissue remains on the ovary after salpingectomy in a significant proportion of cases and could impact the level of risk-reduction that is obtained.

The conceptual advances of carcinogenic sequence model in high-grade serous ovarian cancer

The present review focuses on the current status of molecular pathology in high-grade serous cancer (HGSC) and preneoplastic conditions. This article reviews the English-language literature on HGSC, precursor, fallopian tubal epithelium, secretory cells, ciliated cells, secretory cell expansion, secretory cell outgrowth (SCOUT), p53 signature, serous tubal intraepithelial carcinoma (STIC), DNA damage and immunohistochemistry in an effort to identify the precursor-carcinoma sequence in HGSC. The majority of HGSC originates from the fimbriated end of the fallopian tube secretory epithelial cells, while the small part of this disease may develop from ovarian cortical inclusion cyst (CIC). A series of morphological changes from normal fallopian epithelium to preneoplastic to neoplastic lesions were concomitant with the multistep accumulation of molecular and genetic alterations. Recent studies provide a stepwise progression of fallopian tubal epithelium to precursor lesions to carcinoma, with the aid of a 'secretory cell-SCE-SCOUT-p53 signature-STIC-HGSC sequence' model. Immunohistochemical markers, including p53, STMN1, EZH2, CCNE1, Ki67 and γ-H2AX, were gradually increased during the SCOUT-p53 signature-STIC-HGSC sequence. Conversely, PAX2 expression was decreased during the early phase of SCOUT development. Potential genes and proteins are involved in the evolutionary trajectory of the precursor-cancer lineage model. In the present review we examined detailed aspects of the molecular changes involved in malignant transformation from fallopian tube epithelium to HGSC. A precursor condition originating in 'field cancerization' may gain a growth advantage, leading to HGSC.