Immunohistochemical analysis of adenomatoid tumor of the uterus utilizing of monoclonal antibody HBME-1

An adenomatoid tumor (AT), which is a rare benign neoplasm, is found in the uterus and fallopian tubes with nearly equal frequency (1). The tumor is s aid to originate from mesothelium, which is proven by ultrastructural, hist o- and immunochemical examinations (2). However, a few authors have suggest ed an endothelial origin (3). Recently, a novel immunohistochemical marker (HBME-1) has been claimed to h ave some mesothelial specificity. It is an antibody raised against a suspen sion of human mesothelioma cells and recognizes an antigen on the microvill us surface (4, 5). HBME-1 reactivity has been reported to be useful in the differential diagnosis between mesothelioma and adenocarcinoma, because eac h tumor has its own staining pattern (5). To our knowledge, there has been no report on the case of AT by using HBME-1 for immunohistochemical stainin g. Therefore, we carried out immunohistochemical study on a case of AT of t he uterus complicated with leiomyoma and showed HBME-1 staining was suitabl e for the diagnosis of AT.