ONCOGENIC DIFFERENTIATION OF INTRAEPIDERMAL ECCRINE SWEAT DUCT - ECCRINE POROMA POROEPITHELIOMA AND POROCARCINOMA

(1) The epitheliomatous tumor of the eccrine sweat duct unit reveals initial oncogenic growth of intraepidermal tumor nests composed of glycogen rich cells of uniform size and shape having scanty cytoplasm and scanty intercellular bridges. Although the individual cell atypicalities are not particularly market), the tumor masses do invade the dermis. Unique cystic formation is often seen in these tumor nests. The term “eccrine poroepithelioma” is suggested. (2) Presumable carcinomatous growth of the intraepidermal eccrine sweat duct unit is presented. The tumor is characterized by proliferation of glycogen-rich non-keratinizing tumor cells which form ductlike clefts and directly adjoin the basement membrane. The tumor cells exhibit large, clear, finely granular cytoplasm but contain little acid mucopolysaccharide. The individual cells show pronounced atypicality and mitosis. The term “eccrine porocarcinoma” is tentatively proposed. (3) The above evidence supports the existence of a range of benign to malignant oncogenesis in the intraepidermal eccrine sweat duct, eccrine poroacanthoma, porocpithelioma, and porocarcinoma. © 1969 S. Karger AG, Basel.