Prognosis in triple-negative apocrine carcinomas of the breast: A population-based study

Abstract

Background: Triple-negative apocrine carcinoma (TNAC) of the breast is a very rare type of breast cancer. Furthermore, the clinicopathological features, prognosis, and potential impact of treatment strategies in TNAC remain unclear. Methods: Data from the Surveillance, Epidemiology, and End Results (SEER) program were used to identify breast cancer patients diagnosed between 2010 and 2016 with TNAC and triple-negative breast cancer (TNBC, IDC [invasive ductal carcinoma], NOS [not otherwise specified]). Chi-squared tests were used to examine the categorical variables between the two groups. Overall survival (OS) of TNAC and TNBC was assessed by Kaplan-Meier analyses and Cox regression. Breast cancer-specific survival (BCSS) was evaluated by Nelson-Aalen analyses and competing risk regression. Results: We identified 31 362 patients from the SEER database, including 366 patients with TNAC and 30 996 patients with TNBC. TNAC was correlated with older age, lower T stage and lower tumor grade. Patients with TNAC had better OS compared with TNBC patients; the 5-year OS rates were 82.2% vs 73.5% (P