Abstract P3-05-06: Impact on outcome and response to neoadiuvant chemotherapy in triple negative breast cancer patients and BRCA mutations

Abstract

Abstract Background: The effect of germline BRCA mutations on the outcomes of patients with triple-negative breast cancer (TNBC) is not well understood and the expanding access to genetic testing could provide further information about drug sensitivity and patients’ prognosis. In this retrospective study, data collected from TNBC patients with locally advanced disease and susceptible to neoadjuvant chemotherapy (NAC) were used in order to define whether the presence of germline BRCA pathogenic variants could help defining clinical features, prognosis and outcome of this population. Materials and Methods: Seventy-four women with newly diagnosed locally advanced TNBC from July 1, 2014 to July 30, 2017, were enrolled. DNA derived from whole-blood specimens was available for all the TNBC-NAC cohort. We investigated the presence of gBRCA mutations by employing next generation sequencing (NGS) techniques. Tumor and patients’ characteristics, genetic testing results, and outcomes were collected by patients’ medical records. Statistical calculations were performed using the SPSS 24.0 software. Pearson χ2- test for frequencies was used to compare the demographics, tumor characteristics and response to treatment between pathogenic and not pathogenic BRCA variants. Two-sided p-values were considered to be statistically significant if &lt 0.05. Results: Of our 74 TNBC-NAC cohort, 23 patients (31.1%) tested positive for a pathogenic BRCA variant, 4 (5.4%) tested VUS (variant of uncertain significance) and 47 (63.5%) tested negative. Patients were divided in two group according to the presence of pathogenic or not pathogenic BRCA variants. There were no significant differences between the two group respect to the age at cancer diagnosis (median age in BRCA positive women: 50.6, in VUS: 42.2, in BRCA negative: 47.6), the rate of pathologic response after neoadjuvant anthracycline taxane based chemotherapy and the disease recurrence. Conclusion: In our preliminary study, for the first time all the 74 TNBC-NAC patients have been genetically screened for the presence of BRCA variants. Although larger cohort and longer follow-up are needed in order to fully understand if BRCA variants can assess TNBC patients prognosis, our results showed that the BRCA status does not correlate with response to chemotherapy and disease-free survival of TNBC patients. Citation Format: Ida Paris, Roberta Rizza, Carmela Paolillo, Luisa Carbognin, Alessandra Calegari, Giovanni Scambia, Emilio Bria, Ettore Capoluongo, Riccardo Masetti, Andrea Urbani, Mariangela Pasqualoni, Concetta Santonocito. Impact on outcome and response to neoadiuvant chemotherapy in triple negative breast cancer patients and BRCA mutations [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 P3-05-06.