Introduction
Porocarcinoma (PC), first described in 1963 by Pinkus and Mehregan, is a rare malignant skin tumor originating from the intraepidermal ductal portion of the sweat glands. It accounts for an estimated 0.005%–0.01% of all cutaneous carcinomas [1].
The pathogenesis is not fully understood; it was proposed that de novo PC may develop from a pre-existing poroma through various triggers, including exposure to chemical agents, ultraviolet light, trauma, burning or radiotherapy, immunosuppressive drugs, especially after organ transplantation, and acquired immunodeficiency syndrome. It mainly occurs in adults aged between 21 to 90 years, according to different studies. PC occurs in both sexes equally [2-5].
Recent literature has reported that PC most commonly arises on the lower limbs (33%), head and neck (32%), trunk (14.7%), genitalia/buttocks (11.2%), and upper limbs (7.4%). The location on the arms represents only 4.8% of PC common sites (only 14 cases have been registered at the moment) [6-16].
In this case report, we present a case of PC that gradually ulcerated over about 10 months on the left arm of a 93-year-old male patient with various comorbidities with a literature review on PC and its potential therapy.