p53 Expression as a Prognostic Indicator of 5-Year Survival in Endometrial Cancer

Background. One of the most common genetic alterations to occur in human cancers is an alteration of the p53 tumor suppressor gene. The purpose of this article was to build upon the authors' previous work with p53 and determine whether p53 was a prognostic indicator of 5-year survival. Methods. One hundred thirty-seven consecutively surgically treated patients with endometrial cancer had their p53 expression studied by immunoperoxidase staining and quantified by image analysis. All patients were evaluable for 5-year survival. Results. One hundred three patients had endometrioid adenocarcinoma; 6, adenosquamous carcinoma; 14, papillary serous carcinoma; 10, clear cell carcinoma; and 4, undifferentiated carcinoma. p53 expression ranged from 0.0 to 58.2% positive nuclear area with a mean of 11.5% (median 2.6%) for the cohort. For the patients with endometrioid carcinoma, the mean p53 expression was 7.1% while for the nonendometrioid tumors it was 24.6% (P < 0.001). Fifty-nine of the 103 endometrioid tumors (57.3%) stained positive for p53 while 32 of the 34 nonendometrioid (94.1%) tumors stained positive (P < 0.001). Increasing histologic grade correlated with an increasing p53 expression (P = 0.003). The percentage of tumors expressing p53 was found to be higher in FIGO stage II, III, and IV than in FIGO stage I cancer (P = 0.003). However, mean p53 expression did not differ between early (stage I) and advanced (stage II, III, and IV) cancers (P = 0.088). Utilizing 5-year survival as the endpoint for multivariate analysis, FIGO stage (P = 0.0028) and p53 expression (P < 0.001) were the only independent prognostic indicators found. Conclusion. p53 expression is more commonly found in nonendometrioid than in endometrioid adenocarcinoma of the endometrium. It, along with FIGO stage, is an independent prognostic indicator of 5-year survival.