Clear cell hidradenoma: a tumor with basaliomatous changes in the overlying epidermis and follicular infundibula of surrounding skin.
We report a clear cell hidradenoma on the cheek of a Japanese man. We performed the primary operation on the flesh-colored tumor, which had surface telangiectasia. The histopathologic features of the tumor, which indicated an intradermal nodular hidradenoma, consisted mainly of typical clear cells with small numbers of eosinophilic fusiform cells. Most clear cells reacted negatively for CEA, EMA, S-100 protein and KL-1 keratin, but those in and around the cystic and ductal structures reacted positively for CEA, EMA and KL-1 keratin. Ultrastructurally, these clear cells had numerous microvillus processes, abundant intracytoplasmic glycogen granules, and numerous mitochondria. In addition, buds of hyperpigmented keratinocytes hung from the overlying epidermis and thin cords of hyperpigmented keratinocytes proliferated around the follicular infundibula beside the tumor. Within two months of the primary operation, growth of the tumor into the overlying epidermis recurred rapidly. We discuss the histological features of the combination of clear cell hidradenoma with basaliomatous changes of the overlying and surrounding skin and the highly aggressive recurrence of this type of tumor after primary treatment.
Kato
N
N
Department of Dermatology, Otaru City General Hospital, Japan.
Ueno
H
H
D006607:Adenoma, Sweat Gland / Q000473:pathology*; D000368:Aged; D002610:Cheek; D006801:Humans; D008297:Male; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000473:pathology*