MUCINOUS ADENOCARCINOMA LOCATED ON THE RIGHT LABIA

Purpose: To present a case report and review of the literature of a patient with a well differentiated mucinous adenocarcinoma located on the right labia. Methods: A 52 year old African American female, gravida 3, para 2, presented to the clinic with a 8 month history of a pea sized mass on her right labia that had increased in size and tenderness. On physical exam the nodule was located at the internal middle third of the labia minora. The nodule was removed superficially and a diagnosis of a mucinous adenocarcinoma was made. Results: The removed mass was an irregular 1.0 x .8 x .5 cm fragment of gray-white soft tissue with an attached 0.6 x 0.4 cm ellipse of pale tan skin and a 2.1 x 1.5 x 0.5 cm aggregate of gelatinous translucent tan and red-tan mucoid material. Pathology revealed that the mass did not have free margins. Pathology of the labial mass biopsy revealed a well-differentiated mucinous adenocarcinoma with coexpression of mammaglobin and GATA-3 most likely of eccrine origin. Considering the coexpression of mammoglobin and GATA-3, the tumor is presenting a phenotype similar to mucinous carcinoma arising from the breast. However, a bilateral mammogram showed no evidence of malignancy. The decision was made to undergo a radical excisional procedure with a sentinel lymph node biopsy on the right side to determine lymphatic spread of the tumor. Conclusions: Sweat gland tumors of the vulva are a rare type of cancer. There is a lack of clear evidence in the literature regarding this condition. Between 1958 to 2009, 12 patients were described receiving treatment. Of the 12 patients five had recurrence of the cancer, three with distant metastatic disease and two with a localized recurrence. The literature states that radical resection of the tumor with clear margins results in the best outcomes. The literature is unclear as to whether adjunct therapy, radiotherapy or chemotherapy, has added benefits. This is particularly true in the case of radiotherapy as current literature suggests that primary sweat gland tumors tend to be resistant to this modality. In view of coexpression of mammaglobin GATA-3 and the absence of any evidence of breast cancer the diagnosis of a primary sweat gland tumor of the vulva was made.