Related narrative: Eccrine Porocarcinoma
Eccrine porocarcinoma is a rare malignancy arising from the intra-epidermal ductal portion (acrosyringium) of the eccrine sweat glands. It is most often found in older individuals and most commonly in the lower extremity. Some reports cite a preponderance of cases in women and caucasians. Porocarcinoma may be present for years before diagnosis and is usually a single, small, circumscribed nodule or plaque. It may be mistaken for a metastatic adenocarcinoma. It is usually flesh colored, but may be pigmented. There is a possibility that it may arise in the more common benign eccrine poroma. Although usually slow-growing, porocarcinoma may metastasize locally, to regional lymph nodes or distant sites, with the potential for aggressive behavior. In addition to histological features, various tumor markers, particularly P 53, may help identify the lesion, as well as aneuploidy on flow cytometry.
Treatment of primary lesions is wide local excision and regional lymphadenectomy when clinically indicated. Metastatic disease has been treated anecdotally with chemotherapy and interferon alpha-2a with some success.
This case presented some typical and some atypical features. The lesion presented as an isolated, small nodule with a protuberant component that had been present for some time before diagnosis. However, the patient was young, black, and the lesion occurred in the axilla. Pathology showed no residual tumor in the skin, and no lymph node metastasis.
Goedde TA et al. Eccrine porocarcinoma, J Surg Oncol, 55(4):261-4, 1994.
Poiares BA et al. Eccrine porocarcinoma. a review of 24 cases, Ann Dermatol Venereol, 120 (1):107-15, 1993.
Wick MR et al. Adnexal carcinomas of the skin, I, eccrine carcinomas, Cancer, 56(5):1147-62, 1985.
Huet P et al. Metastasizing eccrine porocarcinoma: report of a case and review of the literature, J Am Acad Dermatolol, 35(5 pt 2):860-4, 1996.
Rare skin adnexal carcinoma from epidermal part of sweat gland duct.
Isolated small nodule or plaque.
Older, female, caucasian, lower extremity preponderance.
Initially slow growing, may be present long periods before diagnosis.
Usually flesh colored, may be pigmented.
May metastasize locally, to regional nodes or distally.
Potential for aggressive metastatic growth.
Tumor markers (P 53) and aneuploidy on flow cytometry help identify.
Initial wide (>2cm) local excision with regional lymphadenectomy if clinically indicated.
Anecdotal treatment results of metastatic disease.