P53 IMMUNOREACTIVITY AS PROGNOSTIC MARKET FOR CANCER-SPECIFIC SURVIVAL IN PROSTATE-CANCER

Objectives: The objective of this study was to evaluate the role of p 53 immunoreactivity as a prognostic marker in prostate cancer. Methods : The nuclear accumulation of the aberrant p53 protein was determined by immunohistochemistry on surgical specimens and related to stage, gr ade and cancer-specific survival in 186 prostate cancer patients treat ed with transurethral resection and subsequent surveillance. Results: There was a significant correlation between p53 staining and grade: 2% of the highly differentiated, 8% of intermediately, and 21% of the po orly differentiated tumors stained. Patients with p53-positive tumors had a significantly shorter survival(52 months) than the p53-negative group (123 months). However, in a Cox multiple regression analysis of p53 status, tumor stage, grade, metastasis and age, p53 lost its signi ficance as an independent predictor. Conclusions: p53 is a rare and la te event in prostate cancer, indicating that other molecular mechanism s may be of greater importance in the development of prostate cancer. The predictive value of p53 apparently depends on its association with high grade and advanced stage, and it is not a useful prognostic mark er in prostate cancer. However, p53 status could play a role in the ev aluation of patients prior to radiotherapy since p53 inactivation may produce radioresistant tumors.