Author: Assoc Prof Patrick Emanuel, Dermatopathologist, Auckland, New Zealand, 2014.
Polymorphous sweat gland carcinoma is a rare adnexal tumour and usually presents as a slow growing dermal mass on an extremity. Local recurrence is not uncommon, particularly following incomplete surgical excisions. Metastasis is rare.
Histology of polymorphous sweat gland carcinoma
Polymorphous sweat gland carcinomas are dermally based tumours (figure 1) that show a wide range of morphologic growth patterns ranging from solid, tubular (figures 2, 3), cribriform (figure 4) and ductal. Abrupt transitions between morphologies is a characteristic feature (figure 5, 6).