Objective: Triple-negative breast cancer (TNBC) is characterized by lack of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) expression and accounts for 15-20% of all breast cancers. This study aims to analyze prognostic factors related to a reduction in overall survival (OS), disease-free survival (DFS), and risk of mortality and recurrence in TNBC.
Methods: This is a retrospective observational cohort study. Medical records of 532 patients with breast cancer diagnosed from 2007 to 2020 were analyzed. Of these patients, 93 (17%) were women with TNBC. Ten medical records were excluded, and the final sample was composed of 83 women with TNBC. OS and DFS were estimated by the Kaplan-Meier model. Univariate analysis (log-rank test) and multivariate analysis (Cox regression) were used to examine prognostic factors related to a statistically significant reduction (p<0.05) in OS and DFS and increased risk of mortality and tumor recurrence.
Results: Smoking, advanced clinical stage, larger tumor size, angiolymphatic invasion, positive sentinel lymph node, axillary node involvement, higher cancer burden, surgical treatment with mastectomy, and recurrence were related to a significant decrease in OS and/or DFS and increased risk of mortality and/or recurrence in TNBC. The 10-year OS and DFS was around 61 and 65%, respectively.
Conclusions: Advanced clinical stage, positive sentinel lymph node, axillary node involvement, surgical treatment with mastectomy, and higher residual cancer burden were related to a significant reduction in OS and DFS and increased risk of mortality and recurrence in TNBC.