Thymidine phosphorylase expression in tumor stroma of uterine cervical carcinomas: histological features and microvessel density.

Immunohistochemical staining was performed on 91 cases of uterine neoplasm in order to determine if expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase (TP) correlates with tumor microvessel density (MVD) and histological parameters of uterine carcinomas in tumor cells and in tumor stroma. The sample group consisted of 72 primary invasive squamous cell carcinomas of the cervix (ISC) and 19 cervical intraepithelial neoplasms (CIN) of the uterus. In ISC of the cervix, TP expression in tumor stroma showed a significant correlation with a non-keratinizing histological subtype (P < 0.001) and with an infiltrating invasive pattern (P < 0.001). However, in tumor cells the TP expression showed a higher correlation with a keratinizing histological subtypes (P = 0.009). MVD was significantly higher (P = 0.002) in tumors showing high TP expression in stroma than in tumors with low expression. These findings suggest that the TP expression in stromal cells, rather than in tumor cells, may play a role in promoting microvessel growth in cervical squamous cell carcinoma, and angiogenesis may also have an association with tumor cell invasion.