The middermis and deep reticular dermis showed a well-circumscribed tumor consisting of polyhedral basaloid cells with medium to large nuclei and focal cytoplasmic clearing. Cystic spaces were present. There were focal ductal differentiation and deposition of pale-pink hyaline material.
Nodular hidradenoma has been described by various names, including clear cell hidradenoma, eccrine sweat gland adenoma of the clear cell type, eccrine acrospiroma, clear cell myoepithelioma, solid cystic hidradenoma, and dermal sweat duct tumor. Nodular hidradenoma is traditionally classified as an eccrine gland tumor, but there is increasing evidence that some of these lesions are of apocrine origin.1,2
Solitary Ulcerated Nodule on the Leg. Arch Dermatol. 2000;136(11):1409-1414. doi: