Purpose: The objective of this study was to determine Bcl-2 expression in localized prostate cancer and its potential role as a predictive factor for biochemical recurrence (BCR).
Materials and methods: This study included 171 Korean patients with newly diagnosed adenocarcinoma of the prostate who underwent radical prostatectomy (RP) without neoadjuvant therapy at a single center between February 2005 and May 2009. RP specimens obtained from these patients were analyzed for the expression of Bcl-2 using tissue microarray. The values of Bcl-2 and other clinicopathologic factors were evaluated. Statistical analysis was performed with contingency table analysis, chi-square tests, and a Cox proportional hazard model.
Results: Bcl-2 expression was immunohistologically-confirmed in 42 patients (24.6%). Bcl-2 expression was not associated with conventional clinicopathologic factors. Bcl-2 negative patients had a significantly longer mean BCR-free survival than Bcl-2-positive patients (p=0.036). Among several variables, a high Gleason score in the RP specimen (≥8), extraprostatic extension, seminal vesicle invasion (SVI), lymphovascular invasion (LVI), and Bcl-2 expression were significant predictors of BCR based on univariate analysis. Multivariate Cox proportional hazards analysis revealed that BCR was significantly associated with a high prostate specific antigen level (p=0.047), SVI (p<0.001), a positive surgical margin (p=0.004) and Bcl-2 expression (p=0.012).
Conclusion: Bcl-2 expression in RP specimens is associated with a significantly worse outcome, suggesting a potential clinical role for Bcl-2. Post-operative Bcl-2 could be a significant predictor of outcome after RP.
Keywords: B-cell leukemia/lymphoma 2; Prostatectomy; Prostatic neoplasms; Proto-oncogene proteins; Recurrence.