IMMUNOHISTOCHEMICAL EXPRESSION OF THYMIDINE PHOSPHORYLASE IN HUMAN ENDOMETRIAL CANCER

Objective. To investigate correlations between the expression of thymi dine phosphorylase (TP) by endometrial cancer cells and the density of microvessels within the tumor, the clinicopathologic features, and th e prognosis. Methods. We examined tumor specimens obtained from 46 pat ients with endometrial cancer (9 FIGO stage IA, 16 stage IB, 8 stage I C, 1 stage IIA, 6 stage IIB, and 6 stage IIIC). The cellular expressio n of TP and the intratumoral density of microvessels were determined b y immunohistochemistry using monoclonal antibodies to TP and factor VI II-related antigen, respectively. We investigated the relationship bet ween the cellular expression of TP and the following factors: clinicop athologic features (menopausal status, histologic type, tumor size, hi stologic grade, myometrial invasion, cervical invasion, and metastasis ), the microvessel count, and the disease-free survival period. Result s. Of the 46 tumors, 19 (41%) were TP-positive. The microvessel count was significantly higher in TP-positive tumors than in TP-negative tum ors (P = 0.01, Mann-Whitney U test). There was no significant correlat ion between TP expression and clinicopathologic features, and there wa s no significant difference in the disease-free survival period betwee n patients with TP-positive tumors and patients with TP-negative tumor s. Conclusion. TP expression was not correlated with clinicopathologic features or prognosis, but was associated with an increased density o f microvessels in endometrial cancer. These findings suggest that TP m ay play an important role in angiogenesis and may be involved in the t umorigenesis of endometrial cancer. (C) 1998 Academic Press.