Mateja Krajc

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 METHODS Unpublished data from three centers were supplemented by studies identified in a systematic review of EMBASE, MEDLINE, and the Cochrane library describing women with a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.

Trends and timing of risk-reducing mastectomy uptake in unaffected BRCA1 and BRCA2 carriers in Slovenia

Risk-reducing mastectomy (RRM) is one of key prevention strategies in female carriers of germline BRCA pathogenic/likely pathogenic variants (PV/LPV). We retrospectively investigated the rate, timing and longitudinal trends of bilateral RRM uptake and the incidence and types of cancers among unaffected BRCA carriers who underwent genetic counseling at the Institute of Oncology Ljubljana in Slovenia. Female BRCA carriers without personal history of cancer were included in the study. Clinical data on PV/LPV type, date of RRM, type of reconstructive procedure, occult carcinoma and histopathology results was collected and analyzed. Of the 346 unaffected BRCA carriers (median age 43 years, 70% BRCA1, 30% BRCA2, median follow-up 46 months) who underwent genetic testing between October 1999 and December 2019, 25.1% had a RRM (range 35-50 years, median age at surgery 38 years). A significant difference in time to prophylactic surgery between women undergoing RRM only vs. women undergoing RRM combined with risk-reducing salpingo-oophorectomy was observed (22.6 vs 8.7 months, p = 0.0009). We observed an upward trend in the annual uptake in line with the previously observed Angelina Jolie effect. In 5.7% of cases, occult breast cancer was detected. No women developed breast cancer after RRM. Women who did not opt for surgical prevention developed BRCA1/2-related cancers (9.3%). The uptake of RRM among unaffected BRCA carriers is 25.1% and is similar to our neighboring countries. No women developed breast cancer after RRM while women who did not opt for surgical prevention developed BRCA1/2 related cancers in 9.3% of cases. The reported data may provide meaningful aid for carriers when deciding on an optimal prevention strategy.