Eccrine porocarcinoma is a rare malignancy of the eccrine sweat duct unit. This article brings to 79 the number of cases reported. Our report and a review of the literature illustrate the natural history and pathological findings of this disease. Patients' ages at the time of appearance for treatment range from 19 to 90 years. The lesions show no predilection for site; their location follows the distribution of sweat glands in the body. Thirty-nine percent of all patients had cutaneous, regional lymph node, or visceral metastases. Primary treatment is wide surgical excision. The value of adjunctive therapy has not been proved.