Eccrine Porocarcinoma with Zosteriform Metastasis.

Eccrine porocarcinoma is a rare malignant tumor that develops in the eccrine glands, appearing as a primary tumor, or by malignant transformation of an eccrine poroma. It is a carcinoma with high metastatic and recurrent potential; it has the same incidence in both sexes, and mainly affects the elderly. Its diagnosis, rather than clinical, is histological, and due to the rarity of the disease, it is a pathological challenge. There are no standardized treatment guidelines for porocarcinoma, but surgical resection with tumor-free margins is considered the basis of treatment, in addition to sentinel node biopsy under risk factors and individualization of each patient. For the metastatic form, chemotherapy and radiotherapy are the treatment of choice. Herein, we present the case of a man with eccrine porocarcinoma with extensive zosteriform skin metastasis and lymph node involvement, treated with chemotherapy and concomitant radiotherapy.