Development of Peritoneal Carcinoma in women diagnosed with Serous Tubal Intraepithelial Carcinoma (STIC) following Risk-Reducing Salpingo-Oophorectomy (RRSO)

Cancer genetic counselling for hereditary breast cancer in the era of precision oncology

A relevant percentage of breast cancers (BCs) are tied to pathogenetic (P)/likely pathogenetic (LP) variants in predisposing genes. The knowledge of P/LP variants is an essential element in the management of BC patients since the first diagnosis because it influences surgery and subsequent oncological treatments and follow-up. Moreover, patients with metastatic BCs can benefit from personalized treatment if carriers of P/LP in BRCA1/2 genes. Multigene panels allow the identification of other predisposing genes with an impact on management. Cascade genetic testing for healthy family members allows personalized preventive strategies. Here, we review the advances and the challenges of Cancer Genetic Counseling (CGC). We focus on the area of oncology directed to hereditary BC management describing the peculiar way to lead CGC and how CGC changes over time. The authors describe the impact of genetic testing by targeted approach or universal approach on the management of BC according to the stage at diagnosis. Moreover, they describe the burden of CGC and testing and future perspectives to widely offer testing. A new perspective is needed for models of service delivery of CGC and testing, beyond formal genetic counselling. A broader genetic test can be quickly usable in clinical practice for comprehensive BC management and personalized prevention in the era of precision oncology.

Bilateral Oophorectomy and All-Cause Mortality in Women With BRCA1 and BRCA2 Sequence Variations

Importance

Preventive bilateral salpingo-oophorectomy is offered to women at high risk of ovarian cancer who carry a pathogenic variant in BRCA1 or BRCA2; however, the association of oophorectomy with all-cause mortality has not been clearly defined.

Objective

To evaluate the association between bilateral oophorectomy and all-cause mortality among women with a BRCA1 or BRCA2 sequence variation.

Design, Setting, and Participants

In this international, longitudinal cohort study of women with BRCA sequence variations, information on bilateral oophorectomy was obtained via biennial questionnaire. Participants were women with a BRCA1 or BRCA2 sequence variation, no prior history of cancer, and at least 1 follow-up questionnaire completed. Women were followed up from age 35 to 75 years for incident cancers and deaths. Cox proportional hazards regression was used to estimate the hazard ratios (HRs) and 95% CIs for all-cause mortality associated with a bilateral oophorectomy (time dependent). Data analysis was performed from January 1 to June 1, 2023.

Exposures

Self-reported bilateral oophorectomy (with or without salpingectomy).

Main Outcomes and Measures

All-cause mortality, breast cancer-specific mortality, and ovarian cancer-specific mortality.

Results

There were 4332 women (mean age, 42.6 years) enrolled in the cohort, of whom 2932 (67.8%) chose to undergo a preventive oophorectomy at a mean (range) age of 45.4 (23.0-77.0) years. After a mean follow-up of 9.0 years, 851 women had developed cancer and 228 had died; 57 died of ovarian or fallopian tube cancer, 58 died of breast cancer, 16 died of peritoneal cancer, and 97 died of other causes. The age-adjusted HR for all-cause mortality associated with oophorectomy was 0.32 (95% CI, 0.24-0.42; P < .001). The age-adjusted HR was 0.28 (95% CI, 0.20-0.38; P < .001) and 0.43 (95% CI, 0.22-0.90; P = .03) for women with BRCA1 and BRCA2 sequence variations, respectively. For women with BRCA1 sequence variations, the estimated cumulative all-cause mortality to age 75 years for women who had an oophorectomy at age 35 years was 25%, compared to 62% for women who did not have an oophorectomy. For women with BRCA2 sequence variations, the estimated cumulative all-cause mortality to age 75 years was 14% for women who had an oophorectomy at age 35 years compared to 28% for women who did not have an oophorectomy.

Conclusions and Relevance

In this cohort study among women with a BRCA1 or BRCA2 sequence variation, oophorectomy was associated with a significant reduction in all-cause mortality.

Serous tubal intraepithelial carcinoma (STIC) outcomes in an average risk population

Objective

Serous tubal intraepithelial carcinoma (STIC) are precursors for high grade serous carcinomas (HGSC) of tubo-ovarian origin. It is a rare entity, most commonly described in patients with a BRCA pathogenic variant (PV) undergoing risk-reducing surgery. Little is known about the risk of subsequent HGSC in patients found to have an isolated STIC without a genetic PV. The objective of this study is to report the outcomes of STIC diagnosed in patients with negative genetic testing ("average risk").

Methods

Retrospective population-based cohort study from British Columbia, Canada. Chart review of patients diagnosed with an isolated STIC from January 2012 to May 2022. Average risk patients are defined as individuals with known negative genetic testing results. Treatment and outcomes are described in the "average risk", BRCA PV, and total cohorts.

Results

Twenty-nine patients with isolated STIC were identified. Ten patients had a BRCA PV, four had other variants identified (BRIP1, MLH1, BRIP1 VUS, BRCA 2 VUS), nine had no PV identified ("average risk"), and six were unknown (no genetic testing). Of the nine "average risk" patients, eight (89%) underwent surgical staging. Three (33.3%) had subsequent HGSC diagnosed 29, 70 and 86 months after STIC diagnosis.

Conclusions

STIC identified in patients with negative genetic testing are at risk of subsequent HGSC. Patients developed primary peritoneal HGSC despite surgical staging. These patients should also be included in future meta-analysis to determine outcomes and optimal treatment.

Pathological findings and long-term prognosis in Korean BRCA1/2 mutation carriers undergoing risk-reducing salpingo-oophorectomy

OBJECTIVE

Our study aimed to evaluate the incidence of pathological findings in asymptomatic Korean patients with BRCA1/2 pathogenic variants who underwent risk-reducing salpingo-oophorectomy and to assess their long-term prognosis.

METHODS

We retrospectively analyzed the medical records of patients with a germinal BRCA1/2 pathologic variant who had undergone risk-reducing salpingo-oophorectomy at Asan Medical Center (Seoul, Korea) between January 2013 and December 2020. All pathologic reports were made based on the sectioning and extensively examining the fimbriated end of the fallopian tube (SEE/FIM) protocol.

RESULTS

Out of 243 patients who underwent risk-reducing salpingo-oophorectomy, 121 (49.8%) had a BRCA1 mutation, 119 (48.9%) had a BRCA2 mutation, and three (1.2%) had both mutations. During the procedure, four (3.3%) patients with a BRCA1 mutation were diagnosed with serous tubal intraepithelial carcinoma (STIC) or serous tubal intraepithelial lesion (STIL), and another four patients (3.3%) were diagnosed with occult cancer despite no evidence of malignancy on preoperative ultrasound. In the BRCA2 mutation group, we found one (0.8%) case of STIC, but no cases of STIL or occult cancer. During the median follow-up period of 98 months (range, 44-104) for STIC and 54 months (range, 52-56) for STIL, none of the patients diagnosed with these precursor lesions developed primary peritoneal carcinomatosis.

CONCLUSIONS

Risk-reducing salpingo-oophorectomy, in asymptomatic Korean patients with BRCA1/2 pathogenic variants, detected ovarian cancer and precursor lesions, including STIC or STIL. Furthermore, our follow-up period did not reveal any instances of primary peritoneal carcinomatosis, suggesting a limited body of evidence supporting the imperative need for adjuvant treatment in patients diagnosed with these precursor lesions during risk-reducing salpingo-oophorectomy.

Clinical significance of risk-reducing salpingo-oophorectomy in patients with BRCA1/2 mutation

OBJECTIVE

Serous tubal intraepithelial carcinoma (STIC) is a precursor lesion which is located in the distal fallopian tube and causes high grade serous ovarian carcinoma (HGSOC). The incidence of STIC for women underwent risk reducing salpingo-oophorectomy for BRCA mutation varies from 0.6 to 7% and its clinical outcomes are still unclear. The aim of this study was to demonstrate the incidence of STIC and HGSOC in BRCA1/2 mutation carriers after risk reducing salpingo-oophorectomy (RRSO) and the clinical outcomes of these patients.

MATERIAL AND METHODS

We retrospectively reviewed the records of 48 BRCA1 and/or 2 mutation carriers who underwent prophylactic salpingo-oophorectomy with or without hysterectomy at the Department of Obstetrics and Gynecology, Bursa Uludag University between January 2000 and January 2022.

INCLUSION CRITERIA

BRCA 1 and/or 2 mutation carriers diagnosed by genetic testing, asymptomatic patients with no abnormal findings on pelvic examination.

EXCLUSION CRITERIA

patients with no abnormal findings on pelvic examination and a presence of a personal history of ovarian, fallopian tube or peritoneal cancer.

RESULTS

A total of 48 BRCA 1 and/or 2 mutation carriers underwent RRSO. STIC was diagnosed in 1 (2,0%) patient and restaging surgery was not performed. Primary peritoneal carcinoma (PPC) did not develop during the 20 months follow-up period. One (2.0%) patient was diagnosed with occult ovarian cancer. Restaging surgery was performed and chemotherapy treatments were given after surgery. A pelvic recurrence developed 25 months after the occult cancer diagnosis in the follow up period. One (2.0%) patient with normal histopathological findings after RRSO was diagnosed with peritoneal cancer 57 months after the operation.

CONCLUSION

The risk of PPC continues after RRSO. Therefore, close follow-up procedure is very important for early diagnosis and effective treatment of patients with PPC after RRSO.

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.

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.

Incidence of pelvic high-grade serous carcinoma after isolated STIC diagnosis: A systematic review of the literature

Objective

Serous tubal intraepithelial carcinoma (STIC) is a precursor lesion of pelvic high-grade serous carcinoma (HGSC). Information on treatment and outcome of isolated STIC is rare. Therefore, we reviewed systematically the published literature to determine the incidence of subsequent HGSC in the high- and low-risk population and to summarize the current diagnostic and therapeutic options.

Methods

A systematic review of the literature was conducted in MEDLINE-Ovid, Cochrane Library and Web of Science of articles published from February 2006 to July 2021. Patients with an isolated STIC diagnosis and clinical follow-up were included. Study exclusion criteria for review were the presence of synchronous gynaecological cancer and/or concurrent non-gynaecological malignancies.

Results

3031 abstracts were screened. 112 isolated STIC patients out of 21 publications were included in our analysis with a pooled median follow-up of 36 (interquartile range (IQR): 25.3-84) months. 71.4% of the patients had peritoneal washings (negative: 62.5%, positive: 8%, atypic cells: 0.9%). Surgical staging was performed in 28.6% of all STICs and did not show any malignancies. 14 out of 112 (12.5%) patients received adjuvant chemotherapy with Carboplatin and Paclitaxel. Eight (7.1%) patients developed a recurrence 42.5 (IQR: 33-72) months after isolated STIC diagnosis. Cumulative incidence of HGSC after five (ten) years was 10.5% (21.6%). Recurrence occurred only in BRCA1 carriers (seven out of eight patients, one patient with unknown BRCA status).

Conclusion

The rate of HGSC after an isolated STIC diagnosis was 7.1% with a cumulative incidence of 10.5% (21.6%) after five (ten) years. HGSC was only observed in BRCA1 carriers. The role of adjuvant therapy and routine surveillance remains unclear, however, intense surveillance up to ten years is necessary.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021278340.

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.

Risk of Peritoneal Carcinomatosis After Risk-Reducing Salpingo-Oophorectomy: A Systematic Review and Individual Patient Data Meta-Analysis

PURPOSE

After risk-reducing salpingo-oophorectomy (RRSO), BRCA1/2 pathogenic variant (PV) carriers have a residual risk to develop peritoneal carcinomatosis (PC). The etiology of PC is not yet clarified, but may be related to serous tubal intraepithelial carcinoma (STIC), the postulated origin for high-grade serous cancer. In this systematic review and individual patient data meta-analysis, we investigate the risk of PC in women with and without STIC at RRSO.

METHODS

Unpublished data from three centers were supplemented by studies identified in a systematic review of EMBASE, MEDLINE, and the Cochrane library describing women with a BRCA-PV with and without STIC at RRSO until September 2020. Primary outcome was the hazard ratio for the risk of PC between BRCA-PV carriers with and without STIC at RRSO, and the corresponding 5- and 10-year risks. Primary analysis was based on a one-stage Cox proportional-hazards regression with a frailty term for study.

RESULTS

From 17 studies, individual patient data were available for 3,121 women, of whom 115 had a STIC at RRSO. The estimated hazard ratio to develop PC during follow-up in women with STIC was 33.9 (95% CI, 15.6 to 73.9), P < .001) compared with women without STIC. For women with STIC, the five- and ten-year risks to develop PC were 10.5% (95% CI, 6.2 to 17.2) and 27.5% (95% CI, 15.6 to 43.9), respectively, whereas the corresponding risks were 0.3% (95% CI, 0.2 to 0.6) and 0.9% (95% CI, 0.6 to 1.4) for women without STIC at RRSO.

CONCLUSION

BRCA-PV carriers with STIC at RRSO have a strongly increased risk to develop PC which increases over time, although current data are limited by small numbers of events.

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.

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.

Hereditary gynecologic tumors and precision cancer medicine

Gynecologic cancers are more often caused by genetic factors than other cancers. Genetic testing has become a promising avenue for the prevention, prognosis, and treatment of cancers. This review describes molecular features of gynecologic tumors linked to hereditary syndromes, gives an overview of the current state of clinical management, and clarifies the role of gynecology in the treatment of hereditary tumors. Typical hereditary gynecologic tumors include hereditary breast and ovarian cancer, Lynch syndrome, Peutz-Jeghers syndrome, and Cowden syndrome. Multigene panel testing, which analyzes a preselected subset of genes for genetic variants, has recently become the first-choice test because it can provide more accurate risk assessment than a single test. Furthermore, comprehensive genomic cancer profiling enables personalized cancer treatment and aids in germline findings.

Efficacy of risk-reducing salpingo-oophorectomy in BRCA1-2 variants and clinical outcomes of follow-up in patients with isolated serous tubal intraepithelial carcinoma (STIC)

OBJECTIVE

Serous tubal intraepithelial carcinoma (STIC) is currently considered the precursor lesion of pelvic high-grade serous carcinoma. The management of STIC diagnosed after risk-reducing salpingo-oophorectomy (RRSO) in women with BRCA1-2 variants remains unclear. The aim of our study was to evaluate the incidence of STIC, serous tubal intraepithelial lesions (STIL) and occult invasive cancer (OC) and to determine the long-term outcomes of these patients.

METHODS

We conducted a retrospective study of patients with BRCA 1-2 variants who underwent RRSO between January-2010 and Dicember-2020 at the Clinic of Gynaecology of University of Padova.

INCLUSION CRITERIA

women with a negative pelvic examination at the last screening prior to RRSO, patients with fallopian tubes analysed using the SEE-FIM protocol.

EXCLUSION CRITERIA

patients with a positive gynaecologic screening or with ovarian/tubal cancer prior to RRSO.

RESULTS

We included 153 patients. STICs were diagnosed in 4 patients (2.6%) and STILs in 6 patients (3.9%). None of the patients with STIC underwent restaging surgery or adjuvant chemotherapy; all patients were followed closely every 6 months. None of the patients developed primary peritoneal carcinomas (PPCs) with a median FUP of 54.5 months (15-106). OC was diagnosed in 3 patients (2%). All patients with OC underwent staging surgery, and one patient developed a peritoneal carcinoma (PC) after 18 months by staging surgery.

CONCLUSION(S)

The incidence of STIC, STIL and OC after RRSO in BRCA1-2 variants was low. Our results demonstrated that long-term close surveillance in patients diagnosed with STIC should be considered a possible management strategy.

Peutz-Jeghers syndrome complicated by gastric-type cervical mucinous carcinoma and primary peritoneal carcinoma

A 45-year-old multiparous woman with a STK11 mutation and a history of Peutz-Jeghers syndrome underwent radical hysterectomy and bilateral salpingo-oophorectomy for a gastric-type cervical mucinous carcinoma. Four and a half years later, blood tests revealed elevations in CEA and CA125 tumor marker levels, and computed tomography showed multiple calcifications in the peritoneum. Peritoneal dissemination was suspected, and a laparoscopic biopsy was performed. Histopathology showed a high-grade serous carcinoma, and the patient was diagnosed with a metachronous stage IIIC primary peritoneal carcinoma. She had no BRCA1/2 mutation. After chemotherapy with docetaxel, carboplatin, and bevacizumab, she achieved complete remission.

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.

Prophylactic risk-reducing salpingo-oophorectomy in BRCA mutation carriers: what is going on in a region of northern Italy?

BACKGROUND

BRCA1 mutation carriers are recommended to undergo prophylactic risk-reducing salpingo-oophorectomy (RRSO) between the ages of 35 and 40 or when child bearing is complete, with a possible delay until age 40-45 for BRCA2 mutation carriers.

STUDY QUESTION

Primary outcome was the rate of unsuspected cancer findings during RRSO in a region of northern Italy (Emilia Romagna) and secondary outcomes were details of RRSO: age at surgical intervention, the venue of the procedures in relation to the surgical/pathological quality and the rate/role of concomitant opportunistic hysterectomies.

STUDY DESIGN

Multicentre data collection by invitation to report current RRSO practices.

RESULTS

A total of 222 RRSOs (54.5 % BRCA1, 34.7 % BRCA2, 1.8 % BRCA1 and BRCA2 combined, 5.8 % BRCA-VUS and 3.2 % BRCA not better specified) were reported from 9 different centres, half in non-university hospitals and the remainder in university hospitals. Breast cancer survivors (56.3 %) underwent the RRSO at a younger age (47.8 vs 50.6 years, p =  0.02). The mean and median ages at surgical intervention (49.0 and 48.0, respectively) were similar for BRCA1 and BRCA2 mutation carriers, as was the temporal trend in age distribution, and proportions treated in university and non-university hospitals. A diagnosis of ovarian invasive cancer was reported in 3.5 % of subjects, all BRCA1 or BRCA-combined subjects, at a median and mean age of 57 years (range 42-68). Abnormal tubal findings, such as serous tubal intraepithelial lesions (STIL) (100 %), secretory cell outgrowth (SCOUT) (100 %) and STIC (71.4 %), were mainly reported by pathologists in university hospitals. Of the 222 procedures, 15 (6.7 %) included hysterectomies: in none of these cases was a primitive uterine endometrioid or serous cancer found.

CONCLUSIONS

The results from this multicentre regional study should guide future preventive health policies for RRSO in BRCA mutation carriers.