Efficacy of platinum in advanced triple-negative breast cancer with germline BRCA mutation determined by next generation sequencing

Objective: To compare the efficacy of platinum-and non-platinum-based regimens as first-line treatment for advanced triple-negative breast cancer(TNBC) and analyze the relationship between their efficacy and BRCA gene status.Methods: Retrospectively analyze clinical data of 220 patients diagnosed pathologically with advanced TNBC and treated at the Department of Breast Oncology, Peking University Cancer Hospital from 2013 to 2018 and evaluate the efficacy of chemotherapy. A total of 114 patients had BRCA1/2 gene tested by next generation sequencing(NGS) using peripheral blood, and we analyzed the correlation between their efficacy and BRCA1/2 gene status.Results: Non-platinum-based chemotherapy(NPCT) was administered to 129 and platinum-based chemotherapy(PBCT) to 91 study patients. The clinical benefit rate(CBR) and median progression-free survival(PFS) were not statistically different between NPCT and PBCT groups. The median overall survival(OS) was 30.0 and 22.5 months for PBCT and NPCT group, respectively [P=0.090, hazard ratios(HR)=0.703]. BRCA status was assessed in 114 patients, 14 of whom had deleterious germline BRCA1/2(g BRCA) mutations(seven in each group).In PBCT group, the CBR was 85.7% and 35.1% for patients with and without deleterious g BRCA mutations,respectively(P=0.039). The median PFS were 14.9 and 5.3 months and median OS were 26.5 and 15.5 months for patients with and without deleterious g BRCA mutations, respectively(P=0.001, P=0.161, respectively). Patients in PBCT group had significantly greater rates of grade 3-4 anemia(5.5% vs. 0%) and thrombocytopenia(8.8% vs.0%), whereas palmar-plantar erythrodysesthesia(12.4% vs. 0%) and peripheral neuropathy(8.6% vs. 1.1%)occurred more frequently in NPCT group.Conclusions: Platinum-based regimens are more effective in patients with deleterious g BRCA mutations, but no difference in patients without BRCA gene mutations, so non-platinum is an option in patients without BRCA gene mutations considering the toxicity and side effect. And we recommend that patients with advanced TNBC should have BRCA gene test.