Pigmented porocarcinoma: a case report with review of the literature.

Various benign and malignant non-melanocytic tumors, including skin appendage tumors, sometimes accompany non-neoplastic melanocytes, and this phenomenon has been described as “melanocytic colonization” [1-7]. Porocarcinoma is a rare skin appendage carcinoma related to the sweat gland duct, originally described by Pinkus and Mehregan in 1963 [8]. Its incidence is reported to be 0.004% of skin biopsy specimens [9]. Poroma and porocarcinoma usually lack melanocytes and melanin pigment within the lesion [10, 11]. However, albeit extremely rare, pigmented porocarcinoma has been reported in the English literature [11-17]. Herein, we describe an additional case of pigmented porocarcinoma and review the literature.