Prognostic significance of overexpression of p53 in uterine endometrioid adenocarcinomas with an analysis of nuclear grade

Abstract

Although overexpression of p53 is usually found in uterine serous carcinoma (USC), it is also found in some uterine endometrioid adenocarcinomas (UEA). This report describes the clinicopathological features of the UEA with overexpression of p53 with special reference to a prognostic significance of nuclear grade. Immunohistochemical expression of p53 was examined in 322 UEA and 34 USC. Greater than 50% staining was defined as the overexpression for p53. Cox's univariate and multivariate analyses for UEA were made. There were 57 UEA (20.7%) showing overexpression of p53 and 31 USC (91.2%). The cancer-specific survival rate of patients with UEA without overexpression of p53, UEA with overexpression of p53 and USC was 88.2%, 76.3% and 45.7%, respectively. Univariate analyses showed overexpression of p53 to be a significant prognostic indicator in patients with UEA (P < 0.02). However, multivariate analyses for UEA showed that age, surgical stage, nuclear grade, myometrial invasion and lymphovascular space invasion were independent prognostic factors, while the significances of p53 immunoreactivity and architectural grade disappeared. In correlation between overexpression of p53 and nuclear grade, the patients with nuclear grade 1 and 2 UEA had a good prognosis, regardless of overexpression of p53. The cancer-specific survival rates of patients with nuclear grade 3 UEA with overexpression of p53 was 52.7% and was not significantly different from that of patients with nuclear grade 3 UEA without overexpression of p53 (66.7%) and USC. The prognostic significance of p53 immunostaining could not show in nuclear grade 3 UEA.