Abstract P3-08-51: Association between BRCA mutational status and survival in patients with breast cancer: A meta-analysis

Abstract

Abstract Background: BRCA mutated breast cancer is associated with an aggressive phenotype with marked differences in histological grade and distant metastases and sensitive to PARPi and platinum therapy. Studies evaluating role of BRCA mutations on the survival outcomes in breast cancer (BC) patients have given confounding results due to the differences in clinical and pathological status among study population. Therefore, we assessed the impact of BRCA mutations on survival of BC patients, based on their baseline characteristics and follow-up durations. Methods: Using PICO framework, articles comparing survival outcomes of BC patients having BRCA mutations against sporadic BRCA phenotype were retrieved from PubMed, EMBASE and Cochrane Library. Overall survival (OS) was the primary outcome, with disease free survival (DFS), distant metastasis free survival (DMFS) and breast cancer specific survival (BCCS) as the secondary outcomes. Hazard ratio (HR) with 95% confidence interval (CI) was used for analysis. Sub-group analysis was performed for survival based on age, tumor stage, estrogen receptor status, triple negative breast cancer (TNBC) status, tumor stage (Stage I-III vs I-IV) and follow-up durations. Results: Altogether, 30 articles with 35,972 patients (mean age 45.6 years) were included in the analysis. In BRCA1/2+ group, no significant difference in OS and DFS than BRCA- group were observed (HR: 0.98, 1.36, respectively),have a better DMFS in BRCA- patients than that in BRCA1/2+ patients (HR: 1.32; 95% CI: 0.71, 2.44). However, the difference observed between the groups was insignificant (P = 0.3825). BRCA1+ patients had significantly lower OS (HR [95%CI]: 1.2 [1.08, 1.33]; P<0.001),poor BCSS at 10 years follow-up. DMFS was significantly poor in BRCA1+ patients compared with BRCA- patients both at 5 years follow-up (HR [95%CI]: 1.07 [1.04, 1.10]; P<0.0001) and 10 years follow-up (HR [95%CI]: 1.21 [1.13, 1.29]; P<0.0001).BRCA2+ patients had significantly lower DFS (HR [95%CI]: 1.35 [1.1, 1.67]; P = 0.0049) and BCSS (HR [95%CI]: 1.46 [1.26, 1.7]; P<0.0001) than BRCA2- patients. Among TNBC patients, OS was non-significantly better in BRCA1/2+ patients (HR 0.96, P = 0.803) than in BRCA- patients. However, DFS was significantly poor in BRCA1+ TNBC patients than BRCA1-/TNBC patients (HR [95% CI]:1.65 [1.08, 2.54]; P = 0.0216).Conclusion: BRCA1/2 mutation is associated with poor prognosis in patient with breast cancer. Hence, BRCA testing might help assess patient prognosis and treatment such as PARPi and platinum. Citation Format: Miao Liu, Shu Wang. Association between BRCA mutational status and survival in patients with breast cancer: A meta-analysis [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-51.