eccrine poroma

Epidemiology

• middle age
• frequency - ~2/3 sole or side of foot, hands and fingers next in frequency.
• variant: eccrine poromatosis

Microscopic pathology

• arises in lower portion of epidermis, extends downward, often in anastomosing bands
• uniform cuboidal cells with intercellular bridges
• narrow ductal lumen & occasional cystic spaces in tumor bands
• may be located in epidermis (also hidroacanthoma simplex) or dermis
• cells contain significant amount of glycogen

Differential diagnosis

• seborrheic keratosis
• basal cell carcinoma
• Bowen's disease (which contains cellular atypia)

More general terms

• eccrine neoplasm