NCIt definition : A carcinoma with eccrine differentiation arising from the sweat glands. It may arise
de novo or as a malignant transformation of a pre-existing poroma. It usually grows
in the legs, buttocks, feet, and trunk and usually presents as an ulcerative plaque.
It is characterized by the presence of intraepidermal and dermal nests of malignant
epithelial cells. It may recur after excision and metastasize to the lymph nodes and
less frequently to distal anatomic sites.;