A rare, low-grade sweat gland carcinoma with neuroendocrine differentiation. It usually arises on the eyelids and periorbital skin. It affects mostly older individuals. Women are affected more frequently than men. Morphologically, it is characterized by well-demarcated nodules with cystic, papillary, or cribriform architectural patterns. The neoplastic cells are small to intermediate polygonal to round cells. Small amounts of intracellular or extracellular mucin are present. In some cases, this carcinoma is a precursor of mucinous carcinoma. [from
NCI]