Prognostic influences of BCL1 and BCL2 expression on disease-free survival in breast cancer

Abstract

We investigated the prognostic influences of BCL1 and BCL2 expression on disease-free survival in breast cancer patients. BCL1 and BCL2 expression statuses were assessed by immunohistochemistry using tissue microarrays from 393 breast cancer patients. The Kaplan–Meier estimator and log-rank test were used for survival analyses. The Cox proportional hazards model was used to calculate hazard ratio (HR) and the 95% confidence interval (CI) of survival analyses. BCL1 expression revealed no impact on survival. The high BCL2 group showed superior disease-free survival compared with the low BCL2 group (p = 0.002), especially regarding local recurrence-free survival (p = 0.045) and systemic recurrence-free survival (p = 0.002). BCL2 expression was a significant prognostic factor by univariable analysis (HR, 0.528; 95% CI, 0.353–0.790; p = 0.002) and by multivariable analysis (HR, 0.547; 95% CI, 0.362–0.826; p = 0.004). High BCL2 expression was associated with higher disease-free survival in the hormone receptor (HRc)-positive and human epidermal growth factor receptor 2 (HER2)-negative (HRc(+)/HER2(−)) subtype only (p = 0.002). The high BCL2 group was associated with positive estrogen receptor (ER), positive progesterone receptor (PR), low histologic grade, and age ≤ 50 years. BCL1 expression had no prognostic impact, but BCL2 expression was a significant independent prognostic factor. High BCL2 expression was associated with higher disease-free survival, especially regarding local recurrence and systemic recurrence. The prognostic effect of BCL2 expression was effective only in the HRc(+)/HER2(−) subtype. Favorable clinicopathologic features and a strong association with the ER/PR status could partly explain the superior prognosis of the high BCL2 group. BCL2 expression could be utilized to assess the prognosis of breast cancer patients in clinical settings.