Poroma

Excerpt

Poroma (poroid tumor) is a benign adnexal tumor that usually originates from the terminal duct of the sweat gland. Initially, in 1956 Pinkus et al. described poroma and its poroid (terminal ductal) differentiation and had been thought to be from the eccrine origin. Further reports have shown cases with apocrine, sebaceous, and follicular differentiation. Some authors used to describe this neoplasm with the term acrospiroma. Others consider this as a broad group of neoplasms, including nodular hidradenomas, clear cell hidradenomas, hidroacanthoma simplex, dermal duct tumors, and hidradenoma. Poroma has a potential degenerative progression, and its malignant counterpart is referred to as porocarcinoma developing after several years from a pre-existing poroma.