HER2 is frequently over-expressed in ovarian clear cell adenocarcinoma: possible novel treatment modality using recombinant monoclonal antibody against HER2, trastuzumab.

Ovarian clear cell adenocarcinoma (CCA) is generally chemo-resistant. Recently the poor prognosis and resistance to chemotherapeutic agents of HER2/neu over-expressing tumors have become clear. Thus, we investigated the expression level of HER2 in surgically resected CCA and ovarian serous adenocarcinoma, endometrioid adenocarcinoma, and mucinous adenocarcinoma specimens, as well as CCA cell lines, by an immunohistochemical method.