The immunohistochemical profile was consistent with the one described in AT in usual locations (genital tracts) and was typical for a tumor of mesothelial origin: calretinin (+), CK(cytokeratin) 5/6 (+), CK 7(+), vimentin (+), D2-40 (+), CD31(-) and CD34 (-). This evidence concerns the gene CD34 and ataxia telangiectasia.