p53 and Bcl-2 as significant predictors of recurrence and survival in rectal cancer

The aim of this study was to evaluate the prognostic value of p53 nuclear a ccumulation and Bcl-2 expression after curative surgery for rectal cancer. Immunohistochemistry was performed using monoclonal antibodies (MAb) (DO-1 for p53; anti-human Bcl-2 MAb, clone 124, for Bcl-2) on formalin-fixed, par affin-embedded tissues of 160 rectal carcinomas (UICC stages I III), and re sults were compared with data from the prospective registry of rectal cance r by univariate and multivariate logistic regression model focusing specifi cally on recurrence. Survival was calculated by the Kaplan Meier method and proportional hazards model. p53 nuclear accumulation was documented in 39% (n = 63) of tumours and was associated with a higher incidence of tumour p rogression (local or distant recurrence) and poorer disease-free survival ( P < 0.0001). Bcl-2 expression was detected in 29% (n = 47), and was associa ted with longer disease-free survival and lower incidence of recurrence (P < 0.0086). Multivariate logistic regression analysis demonstrated that gend er (P = 0.0136), UICC stage (P = 0.002), p53 expression (P - 0.0002) and Bc l-2 expression (P = 0.0243) were independent factors predictive of recurren ce. The proportional hazards model identified p53 (P = 0.0009), UICC stage (P = 0.0480), Sender (P 0.0049), but not Bcl-2 (P = 0.1503), as independent ly related to disease-free survival. Looking at the p53/Bcl-2 subgroups, th e poorest prognosis was observed in the p53+/Bcl-2- subgroup, whereas patie nts whose tumours were p53-/Bcl-2 + had the best prognosis (P < 0.0001). Im munohistochemical assessment of both p53 and Bcl-2 status may. be valuable in predicting recurrence and survival after curative surgery for rectal can cer. Therefore, they play a role as prognostic factors in rectal cancer. p5 3 is a stronger predictor of prognosis than Bcl-2. (C) 2000 Else Elsevier S cience Ltd. All rights reserved.