Eccrine Porocarcinoma of Scalp: An Uncommon Tumor at an Unusual Site

Abstract

Eccrine porocarcinoma (EPC) is a very rare malignant sweat gland tumor and those arising in the scalp, are still rarer. Very few cases are reported in literature [1]. Malignant eccrine poroma was first described in 1963 by Pinkus and Mehregan using the term epidermotropic eccrine carcinoma. It is regarded as the rare malignant counterpart of eccrine poroma, a benign tumor of the intraepidermal eccrine sweat gland duct [2]. Porocarcinoma is commonly found in older age group and usually located in the lower extremities (more than 50%), rarely may occur on scalp, face, ear, upper extremities, trunk and abdomen [1, 3]. In the scalp, it is commonly seen in occipital region [4, 5]. The tumor presents as nodular, infiltrative, ulcerated or polypoid growth [6]. Surgical resection is the treatment of choice. There is 17% incidence of local recurrence and an 11% incidence of distant metastasis [3]. We report a case of EPC of scalp arising from a pigmented eccrine poroma in a 35 yr old.