BRCA1/2 mutation carriers & risk reducing mastectomy: Who undergoes surgery and potential benefits

Short-term Patient-Reported Outcomes Following Bilateral Risk-Reducing Mastectomy for Patients at a High Risk for Breast Cancer: A Systematic Review

BACKGROUND

Bilateral risk-reducing mastectomies (RRMs) have been proven to decrease the risk of breast cancer in patients at high risk owing to family history or having pathogenic genetic mutations. However, few resources with consolidated data have detailed the patient experience following surgery. This systematic review features patient-reported outcomes for patients with no breast cancer history in the year after their bilateral RRM.

METHODS

The databases MEDLINE, Embase, and Scopus were used to identify studies. Studies were then evaluated by multiple authors, and their quality was assessed by using the Methodological Index for Non-Randomized Studies score.

RESULTS

Our search identified 1858 unique studies, of which 11 met our inclusion criteria. Only two of these studies included patients who did not receive postmastectomy reconstruction. The included studies were either retrospective cohort studies or prospective studies. General satisfaction with the outcome of RRM and the decision to undergo RRM was high across many of the studies, with low levels of regret. There was also a noticeable trend of improved psychosocial outcomes following RRM. For postoperative sexual well-being, body image, aesthetic satisfactions, and somatosensory function, there were a mix of positive and negative outcomes.

CONCLUSIONS

The patients who elected to manage their breast cancer risk with bilateral RRM (mostly with reconstruction) tend to be satisfied with their decision and the surgical outcomes. This may be related to decreased cancer-related anxiety. Postmastectomy psychosocial well-being tends to improve while physical health after surgery varies by patient.

Impact of Early Testing and Analysis of Germline Genetic Mutation in Patients with Breast Cancer: A Single Institution Experience

Breast cancer is the most common cancer among women worldwide, with germline mutations in high-penetrance genes like BRCA1 and BRCA2, and moderate-penetrance genes such as CHEK2 and ATM contributing majorly to the onset of the same. Universal germline genetic testing offers an avenue to improve early identification and develop appropriate management guidelines. Our retrospective cohort study analyzed data from 525 newly diagnosed breast cancer patients at Mercy Hospital Fort Smith from January 2020 to December 2023. Patients underwent germline genetic testing using next-generation sequencing panels irrespective of family history of cancer. Details on patient demographics, clinical characteristics, and genetic test results were collected and analyzed. The median age at diagnosis of patients was 66, with invasive ductal carcinoma (IDC) being the major subtype (66%). CHEK2 mutations were the most common pathogenic mutations (9 patients), followed by BRCA1 and MUTYH (6 each). Pathogenic mutations were more prevalent in patients over 60 years (63%). Germline mutations were identified more frequently in IDC than in ductal carcinoma in situ. Among patients with germline mutations, there was a significant drift toward mastectomy over breast-conserving surgery. Universal germline genetic testing identified pathogenic mutations in a significant proportion of breast cancer patients, especially among the older patient population. The findings further emphasize the importance of integrating universal genetic testing into routine care to guide surgical and risk-reduction management protocols effectively. Further research is needed to regularize genetic testing in similar patients.

Demographics and Clinical Decision Making in Patients with Germline Moderate Penetrance Non-BRCA Mutations in Breast Cancer Related Genes

BACKGROUND

Management of pathogenic variants in high penetrance genes related to breast cancer (BC), such as BRCA1 and BRCA2, are well established. However, moderate penetrance mutations are understudied. We aim to compare risk reduction decision-making patterns in patients with a moderate penetrance BC-related genetic mutations, without a prior BC diagnosis.

PATIENTS AND METHODS

Female patients aged ≥ 18 years who tested positive for a BRCA1/2, high penetrance, or moderate penetrance mutation related to BC between 1996 and 2023 without a concurrent or prior BC diagnosis were retrospectively identified from a single academic center's database. Groups were stratified by mutation type: BRCA1/2 mutations (BRCA1, BRCA2), high penetrance mutations (HPM; CDH1, PALB2, PTEN, STK11, TP53), or moderate penetrance mutations (MPM; ATM, BARD1, CHEK2, NF1, RAD51C, RAD51D). Demographics and clinical outcomes were compared.

RESULTS

A total of 528 patients met the inclusion criteria, with 66% (n = 350) having a BRCA1/2 mutation, 8% (n = 44) having HPM, and 25% (n = 134) having MPM; the median follow-up was 56.0 months. In our cohort, 20.9% of patients with BRCA mutations, 9.1% with HPM, and 7.5% with MPM chose to undergo risk-reducing mastectomies (RRM). Within the moderate penetrance cohort, patients who chose to undergo RRM were younger at the time of genetic testing (39.4 vs. 47.5 years, p = 0.03) and had a higher number of family members with BC (2 vs. 1, p = 0.05).

CONCLUSIONS

Our findings provide insights into the demographic characteristics and family history of patients with moderate penetrance mutations and those who pursue risk-reducing surgery.

[News in breast oncology genetics for female and male population]

OBJECTIVES

Breast oncology genetics emerged almost 30 years ago with the discovery of the BRCA1 and BRCA2 genes. The evolution of analytical practices has progressively allowed access to tests whose results now have a considerable impact on the management of both female and male breast cancers. The Sénologie commission of the Collège national des gynécologues et obstétriciens français (CNGOF) asked five specialists in breast surgery, oncology and oncological genetics to draw up a summary of the oncogenetic testing criteria used and the clinical implications for the female and male population of the test results, with or without an identified causal variant. In the case of proven genetic risk, surveillance, risk-reduction strategies, and the specificities of surgical and medical management (with PARP inhibitors in particular) were updated.

METHODS

This summary was based on national and international guidelines on the monitoring and therapeutic management of genetic risk, and a recent review of the literature covering the last five years.

RESULTS

Despite successive technical developments, the probability of identifying a causal variant in a situation suggestive of a predisposition to breast and ovarian cancer remains around 10% in France. The risk of breast cancer in women with a causal variant of the BRCA1, BRCA2, PALB2, TP53, CDH1 and PTEN genes is estimated at between 35% and 85% at age 70. The presence of a causal variant in one of these genes is the subject of different recommendations for men and women, concerning both surveillance, the age of onset and imaging modalities of which vary according to the genes involved, and risk-reduction surgery, which is possible for women as soon as their risk level exceeds 30% and remains exceptionally indicated for men. In the case of breast cancer, PARP inhibitors are a promising new class of treatment for BRCA germline mutations.

CONCLUSION

A discipline resolutely focused on understanding molecular mechanisms, screening and preventive medicine/surgery, oncology genetics is currently also involved in new medical/surgical approaches, the long-term benefits/risks of which will need to be monitored.