Vulvar eccrine porocarcinoma: report of a case and literature review

Adnexal carcinomas of the vulva are rare tumors. A case of an 83-year-old woman with a 3.5 cm vulvar lobulated mass that grew over an 18-month period is reported. Histopathological examination of the initial biopsy revealed a poorly differentiated infiltrating carcinoma. Treatment included radical vulvectomy with bilateral inguinal lymphadenectomy. The histological examination of the vulvectomy specimen resulted in eccrine porocarcinoma (EPC) diagnosis. A review of the literature disclosed eight vulvar cases previously reported. The study of the nine cases including the present revealed that the ages of the patients ranged from 32 to 88 years, with a mean of 66.1 years. The location of the tumor was most common in the labium majus. The size ranged from 2 cm to 5 cm (mean 3.3 cm). A longstanding history suggested that at least two (22.2%) tumors arose from a preexistent benign eccrine poroma. Considering the reduced prevalence of EPC, the diagnosis of this type of tumor is challenging. The follow-up varied from six to 132 months (mean 35.2 months). Two (22.2%) tumors recurred, three (33.3%) patients developed regional lymph node metastases, and two (22.5%) patients showed distant metastases. Only one patient died of the disease, two patients remained alive with tumor, and four (44.4%) patients showed no evidence of disease. Although a rare entity, EPC should be considered in the differential diagnosis of a vulvar mass. In the vulva, it is difficult to establish the clinicopathological predictors of prognosis of EPC. However, the markers of aggressiveness at extragenital sites may also apply to this vulvar tumor.