Clinical and microscopic data on 41 solidcystic hidradenomas are presented. These tumors occur more frequently in females than in males and may be found in all regions of the body and in patients of any age although there is a predilection for the middle and older age groups. The lesions are solitary and represent cutaneous and subcutaneous nodular and cystic masses of slow, expansile growth. Histologically they are solid and cystic and are composed of epidermoid cells which may undergo transformation into clear cells. The tumors contain glycogen, but acid mucopolysaccharides are found only occasionally and only in minute amounts. None of the 41 tumors showed signs of malignancy. Our findings indicate that solid-cystic hidradenoma of the skin represents a clinically and microscopically distinct sweat gland neoplasm which should be separated from other types of hidradenomas and appendageal tumors.
Winkelmann RK, Wolff K. Solid-Cystic Hidradenoma of the SkinClinical and Histopathologic Study. Arch Dermatol. 1968;97(6):651-661. doi:10.1001/archderm.1968.01610120041005