p53 as a prognostic indicator 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. Although endometrial cancer is the most common gynecologic malignancy in the United States, any connection between it and p53 is just beginning to be explored. Methods: Forty-six consecutively surgically treated patients with endometrial cancer had their p53 expression studied by immunoperoxidase staining and quantified by image analysis. Results: Thirty-five patients had endometrioid adenocarcinomas, 3 had adenosquamous carcinomas, 3 had papillary serous carcinomas, 3 had clear cell carcinomas, and 2 had undifferentiated carcinomas. p53 expression ranged from 0.0 to 55.8% with a mean of 10.7% for the cohort. For the patients with endometrioid carcinomas, the mean p53 expression was 3.9%, while for those with more aggressive histologies it was 32.4% (P < 0.001). Sixteen of the 35 endometrioid tumors (45.7%) stained positive for p53, while 11 of the remaining 12 (91.2%) tumors with more aggressive histologies stained positive (P < 0.01). Increasing histologic grade correlated with an increasing p53 expression (P = 0.006). The percentage of patient tumors expressing p53 was found to be higher in FIGO stage II, III, and IV than in FIGO stage I cancer (P = 0.01). However, the mean p53 expression was not different between early (stage I) and advanced (stage II, III, and IV) cancers (P = 0.55). Utilizing recurrence as the endpoint for multivariate analysis, FIGO stage and p53 expression were the only independent prognostic indicators found. Conclusion: p53 expression is more common in more aggressive histologic subtypes than in endometrioid adenocarcinomas. It is an independent prognostic indicator of disease recurrence. (C) 1996 Academic Press, Inc.