P53/MDM2 overexpression in metastatic endometrial cancer: correlation with clinicopathological features and patient outcome

Several studies have reported that p53/mdm2 distortions play a pivotal role in the development and progression of various human malignancies. However, the number of reports having evaluated simultaneously the components of the P53-pathway alterations in advanced-stage human endometrial carcinomas (EC) is low. In this study, we examined the expression of P53/MDM2 proteins in primary and metastatic ECs, and analyzed the clinicopathological characteristics as well as the survival outcome of patients in relation to P53/MDM2 overexpression. The study group comprised 36 patients with advanced EC, whose primary and metastatic tumor slides were sufficient for analysis. Immunohistochemical assessment was made by applying anti-human P53 and MDM2 antibodies and a highly sensitive EnVision+/HPR visualization system. Nuclear P53 overexpression was seen in 11 (31%) primary ECs and 12 (33%) metastatic tumors. There was a significant correlation between P53 overexpression (in primary cancers and metastatic tumors) and MDM2 overexpression in metastatic tumors. Nuclear MDM2 overexpression was noted in 42% (15/36) of primary carcinomas and in 47% (17/36) of metastatic tumors. A significant association existed between MDM2 overexpression and histological grading (G1 + G2 versus G3, P = 0.043). P53/MDM2 overexpression occurred simultaneously in 7 out of 36 (19%) primary ECs and in 9 out of 36 (25%) metastatic lesions. Concomitant overexpression of these proteins was reported in 7 out of 36 (19%) cases and tended to be higher in tumors showing VSI compared to neoplasms lacking vascular space invasion (P = 0.051). P53 overexpression, either in primary ECs (P