title: Malignant hidroacanthoma simplex. A light microscopic, ultrastructural, and immunohistochemical study of 2 cases.
abstract: 2 cases of malignant hidroacanthoma simplex are reported. Prominent ultrastructural findings were sparse tonofilaments and villous-like, interdigitating cytoplasmic processes connected by small desmosomes. Positive intracytoplasmic stain for carcinoembryonic antigen was found in 1 case. Benign and malignant eccrine poromas and hidroacanthoma simplex appear to be related neoplasms on the basis of ultrastructural and immunohistochemical findings.
mesh_terms: D006607:Adenoma, Sweat Gland / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure*; D000368:Aged; D002272:Carcinoembryonic Antigen / Q000032:analysis; D005260:Female; D006801:Humans; D008854:Microscopy, Electron; D012878:Skin Neoplasms / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D002272:Carcinoembryonic Antigen