Poroma

Poroma (poroid tumor), a benign adnexal tumor, usually originates from the terminal duct of sweat glands. Initially, Pinkus et al described poroma and its differentiation in 1956, which was initially believed to be of eccrine origin. However, further research has revealed cases of apocrine, sebaceous, and follicular differentiation. Some authors describe this neoplasm as "acrospiroma," whereas others consider poroma as a broad group of neoplasms, including nodular hidradenomas, clear cell hidradenomas, hidroacanthoma simplex, dermal duct tumors, and hidradenoma. Poroma can exhibit potential degenerative progression. Porocarcinoma, its malignant counterpart, typically develops after several years from a preexisting poroma.