Endometrial carcinoma associated with hyperplasia--immunohistochemical study of angiogenesis and p53 expression.

Objective: To clarify the hypothesis that there are two pathways of endometrial carcinogenesis we compared the frequency of abnormal p53 protein expression and angiogenesis in endometrial carcinomas with and without hyperplasia.

Methods: Specimens obtained from 70 patients with stage I-IV endometrial carcinomas were available for this immunohistochemical study. Immunohistochemical staining for factor VIII-related and p53 antigens was performed using a standard immunoperoxidase technique (Histofine SAB-PO Kit, Nichirei Co., Tokyo, Japan). Microvessels were highlighted by staining endothelial cells for factor VIII-related antigen, and microvessel density (MVD) was counted in a x200 field (0.785 mm2 per field) in the area of most active neovascularization. p53 protein was detected with monoclonal anti-p53 antibodies (clone DO-7, Dako, Santa Barbara, CA).

Results: Twenty-six of 73 (37%) patients had hyperplasia in the endometrium adjacent to the carcinoma. Significantly more patients with low MVD (less than 60) had carcinoma with hyperplasia than those with carcinoma without hyperplasia (P = 0.0053). p53 expression was noted in a carcinomatous area in 8 of 26 patients (30. 8%) with hyperplasia compared to 26 of 44 (59.1%) without hyperplasia, and the difference was statistically significant (P = 0. 0220).

Conclusion: The presence or absence of hyperplasia is a different pathogenesis and important in assessing the biological behavior of endometrial carcinoma, especially concerning angiogenesis and p53 expression.