Effectiveness of neoadjuvant therapy with platinum-based agents for patients with BRCA1 and BRCA2 Germline mutations- a retrospective analysis of breast cancer patients treated at MMCI Brno

Abstract

Background: Mutations in the BRCA1 and BRCA2 genes are associated with a high risk of developing breast cancer. Tumors arising from this mutation are expected to be more sensitive to platinum-based drugs. The role of platinum-based drugs in systemic neoadjuvant BRCA1/2 breast cancer therapy, and its efficacy in increasing the probability of pathological complete remission (pCR) are discussed repeatedly; however, there are no clear recommendations. Patients and methods: We retrospectively evaluated the contribution of a platinum-based antineoplastic drug to the achievement of pCR in a set of patients with BRCA1/2 mutant breast cancer treated with neoadjuvant chemotherapy from 2010 to 2017. The response to neoadjuvant chemotherapy was evaluated by a pathologist using definitive surgical specimens. A pCR was defined as a condition in which complete invasive breast cancer, and (eventually) positive lymph nodes, had disappeared. Results: Of 76 patients (median age, 39 years; 62% with triple negative breast cancer (TNBC); 70% with BRCA1 positivity), 37 were treated with platinum-based drugs. More patients treated with platinum derivatives achieved pCR (57% vs. 23%, p = 0.005). Patients treated in a neoadjuvant setting with platinum-based antineoplastic drugs had a 4.4× greater chance of achieving pCR than those not treated with platinum, assuming the same tumor phenotype (TNBC or SR+HER2−). Conclusion: Neoadjuvant platinum-based chemotherapy for patients with a BRCA1/2 mutation is associated with a higher probability of achieving pCR, which is important for subsequent prognosis. This treatment should be considered particularly for patients with BRCA1 mutation and a TNBC phenotype.