O. Ortmann

Hormone replacement therapy in BRCA mutation carriers and risk of ovarian, endometrial, and breast cancer: a systematic review

Abstract Purpose BRCA mutation carriers have an increased risk of developing breast or ovarian cancer. Risk-reducing bilateral salpingo-oophorectomy (RRBSO) is associated with a decrease in risk for tubal and ovarian cancer. Hormone replacement therapy (HRT) may increase breast, ovarian, and endometrial cancer risk in the general population. This review analyses the published data on HRT and risk of cancer in BRCA mutation carriers with and without RRBSO. Methods We included all relevant articles published in English from 1995 to October 2020. Sources were identified through a search on PubMed and Cochrane Library. Results We included one case–control and one retrospective cohort study on ovarian and one case–control study on endometrial cancer risk and HRT in BRCA mutation carriers. Regarding breast cancer risk, one case–control study on BRCA mutation carriers with and without RRBSO and one case–control study, one Markov chain decision model, two prospective cohort studies, and one metaanalysis on carriers after RRBSO were included. For ovarian cancer, results were ambiguous. For breast cancer, most studies did not find an adverse effect associated with HRT. However, some of the studies found a risk modification associated with different formulations and duration of use. Conclusion Although data are limited, HRT does not seem to have a relevant effect on cancer risk in BRCA mutation carriers. RRBSO should not be postponed to avoid subsequent HRT in this population. Adequate HRT after RRBSO should be offered to avoid chronic diseases resulting from low estrogen levels. However, further data on the safety of different formulations are needed.

Use of fertility treatments in BRCA1/2 mutation carriers and risk for ovarian and breast cancer: a systematic review

Abstract Purpose Mutations in the genes BRCA1 and BRCA2 represent a significant risk factor for ovarian and breast cancer. With increasing number and success rates, fertility protection and treatment are gaining importance also for BRCA1/2 mutation carriers. However, the effect on primary cancer risk and risk for recurrence remains unclear. This review analyses the published data on fertility treatment and risk of ovarian and breast cancer in BRCA1/2 mutation carriers. Methods In this review, we included all relevant articles published in English from 1995 to 2018. Literature was identified through a search on PubMed and Cochrane Library. Results We identified one retrospective cohort and one case–control study regarding the association of fertility treatments and ovarian cancer risk in BRCA mutation carriers. The studies show no increase in ovarian cancer risk. Furthermore, one case–control study on the association between fertility treatment and breast cancer risk in BRCA mutation carriers and one prospective cohort study on the long-term safety of medication used for fertility preservation in women with a history of breast cancer were identified. One of the studies shows a possible adverse effect for gonadotropin-containing medication. Conclusion Possible increases in cancer risk associated with fertility treatments in BRCA1/2 mutation carriers cannot be excluded at this time. Based on the existing studies, BRCA1/2 mutation carriers should not be generally excluded from fertility treatments. However, they have to be informed about limited data and possible increases in cancer risk.

Use of oral contraceptives in BRCA mutation carriers and risk for ovarian and breast cancer: a systematic review

Abstract Purpose BRCA mutation carriers have an increased risk of developing breast or ovarian cancer. Oral contraception (OC) is known to increase breast cancer and reduce ovarian cancer risk in the general population. This review analyses the published data on OC and risk of cancer in BRCA mutation carriers. Methods We included all relevant articles published in English from 1995 to 2018. Literature was identified through a search on PubMed and Cochrane Library. Results We included four meta-analyses, one review, one case–control study and one retrospective cohort study on the association between ovarian cancer and OC in BRCA mutation carriers. All report a risk reduction for the OC users and several also describe an inverse correlation with duration of use. Regarding breast cancer, we included four meta-analyses, one review, one case–control study, two case-only studies, one prospective and one retrospective cohort study. Some studies report a risk elevation, while others did not find an association between OC use and breast cancer in BRCA mutation carriers. In other studies, the association was limited to early-onset breast cancer and/or associated with young age at first start of OC. Conclusion Oral contraception leads to a risk reduction of ovarian cancer also in BRCA mutation carriers. An increase in breast cancer risk due to OC cannot be excluded. Women with BRCA mutation who consider OC use have to be informed about possible increase in breast cancer risk and alternative contraceptive methods. OC should not be used for the prevention of ovarian cancer in this population.