[Three cases of adenomatoid tumor of the uterus]

Adenomatoid tumors arising in the uterus are not well-recognized and sometimes mistaken for other benign or malignant neoplasms. This study describes three cases of uterine adenomatoid tumors with clinical, light microscopic, histochemical and electron microscopical studies. Four distinctive histologic patterns (solid, adenoid, angiomatoid, cystic) were identified. Acid mucopolysaccharide was present in three cases and was digested by hyaluronidase. Immunohistochemically, tumor cells were positive for cytokeratin and vimentin. Electron microscopy revealed microvilli, intermediate filaments and dilated intercellular spaces. This gives further support to a mesothelial origin of the adenomatoid tumor. Interestingly, one case showed that the adenomatoid tumor was multiple and one nodule was connected with leiomyomatous nodule. In the other case, the tumor was large 5 x 4 x 4.5 cm). These features were unusual.