Metastatic eccrine porocarcinoma.

Eccrine porocarcinoma (EP) is a rare malignant tumor arising from the intraepidermal sweat duct. The lesions have a varied clinical appearance and usually are asymptomatic. In reported cases, metastasis is rare but can be devastating when it occurs. We describe an unusual case of EP in a patient who presented with metastatic disease. New-onset exquisite pain prompted his evaluation. This case and review of metastatic disease is presented to raise awareness of this tumor, its varied clinical presentations, differential diagnosis, and management.