clear cell hidradenoma

・大腿部に生じたclear cell hidradenoma（CCH）を報告した．

・超音波画像検査では低エコー領域に高エコー領域が突出する所見がみられた．

・病理組織学的所見で断頭分泌がみられたものの，免疫化学染色ではluminal cell がcarcinoembryonic antigen（CEA）とepithelial membrane antigen（EMA），34βE12が陽性，clear cellがEMAと34βE12が陽性であったことから，表皮内汗管と真皮内汗管の外壁細胞への分化傾向が考えられた．

（「症例のポイント」より）

　

A case of clear cell hidradenoma

　

Oya, Kazumasa1）Taguchi, Shijima2） 1）Department of Dermatology, Faculty of Medicine, University of Tsukuba 2）Dermatology, Mito Kyodo General Hospital

　

A 32-year-old male presented with a nodule on his left thigh. Physical examination revealed a 15×13-mm dark, dome-shaped nodule. Histopathological examination revealed that the mass consisted of solid and cystic areas. Clear cells and epidermoid cells were seen in the solid area. Duct-like structures lined by a layer of luminal cells were also present. Based on these findings, a diagnosis of clear cell hidradenoma was made. Immunohistochemical studies showed that the luminal cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and 34βE12； and the clear cells were positive for EMA and 34βE12, which suggested the tumor had characteristics of acrosyringium with an outer layer consisting of dermal duct cells.