Abstract
We studied the association of the immunohistochemical bcl-2 expression in Libyan breast cancer with clinicopathological variables and patient outcome. Histological samples from 170 previously untreated primary Libyan breast carcinoma patients were examined. In immunohistochemistry, the NCL-l-bcl-2-486 monoclonal antibody was used. Positive expression of bcl-2 was found in 106 patients (62.4 %). The bcl-2 expression was significantly associated with estrogen receptor (p < 0.0001) and progesterone receptor positive tumors (p = 0.002), small tumor size (p < 0.0001), low tumor grade (p < 0.0001), negative axillary lymph nodes (p < 0.0001), early stages (p = 0.001), and low risk of metastasis (p < 0.0001). Positive expression was also associated with older patients (> 50 years; p = 0.04). Histological subtypes and family history of breast cancer did not have significant relationship with bcl-2. Patients with positive expression of bcl-2 had lower recurrence rate than bcl-2-negative patients and better survival after median follow-up of 47 months. Patients with high bcl-2 staining were associated with the best survival. The role of bcl-2 as an independent predictor of disease-specific survival was assessed in a multivariate survival (Cox) analysis, including age, hormonal status, recurrence, histological grade, and clinical stage variables. Bcl-2 (p < 0.0001) and clinical stage (p = 0.016) were independent predicators of disease-specific survival. For analysis of disease-free survival, the same variables were entered to the model and only bcl-2 proved to be an independent predictor (p = 0.002). Patients with positive expression of bcl-2 were associated with low grade of malignancy, with lower recurrence rate, with lower rate of death, and with longer survival time. Bcl-2 is an independent predictor of breast cancer outcome, and it provides useful prognostic information in Libyan breast cancer. Thus, it could be used with classical clinicopathological factors to improve patient selection for therapy.