Eccrine porocarcinoma of the vulva: a case report and review of the literature

Abstract

Background: Malignant tumors arising from the vulva account for only 0.6 % of all cancers in female patients. The predominant histologic type, representing about 90 % of these malignancies, is squamous cell carcinoma. Eccrine porocarcinoma is a rare malignant tumor arising from sweat glands. The incidence of eccrine porocarcinoma is estimated at 0.005-0.01 % of all cutaneous tumors. To the best of our knowledge, only seven previous cases of vulvar eccrine porocarcinoma have been reported in the English-language literature. We present the case of a patient with eccrine porocarcinoma of the vulva, and we summarize the clinical features of this disease using seven previously reported cases.

Case presentation: A 54-year-old Japanese woman visited a local hospital complaining of fever and left vulvar pain for 2 months. An initial examination revealed a 1 × 1 cm, firm, ulcerative mass in the inner aspect of the left labium minorum. With a preoperative diagnosis of vulvar squamous cell carcinoma, we performed a radical local excision followed by bilateral inguinal lymphadenectomy. Histological examination showed eccrine porocarcinoma, stage IB (T1bN0M0). Radiation therapy with weekly cisplatin administration was then given as adjuvant therapy. One month after treatment was completed, computed tomography revealed multiple metastases in the bilateral lungs and in the sacral bone. The patient received three courses of chemotherapy (paclitaxel and carboplatin) and underwent palliative radiation therapy to the sacrum. She died of her disease 12 months after surgery.

Conclusions: We report the case of a patient with eccrine porocarcinoma of the vulva and summarize the clinical features and the treatment options of eccrine porocarcinoma from a few retrospective case reports. Although eccrine porocarcinoma is a rare disease, clinicians and pathologists should be aware of its clinical and histological features and its biological behavior.

Keywords: Case report; Eccrine gland; Immunohistochemistry; Porocarcinoma; Squamous cell carcinoma; Vulva.

Fig. 1

Physical examination and clinical imaging. a Ulcerative lesion on the inner side of the left labium minorum (arrow). b T1-weighted, contrast-enhanced magnetic resonance image revealing a 31 × 24 mm mass of moderate-to-high intensity in the left vulvar region (arrow); the mass does not involve the urethra or anus. c Positron emission tomography computed tomography revealing tumor metastases to the sacrum (arrow)

Fig. 2

Histopathology and immunohistochemistry of sections of vulva tumor. a Tumor cells appearing as solid nests of cells resembling large alveolar glands, broadly connected to the epidermis (arrow) (hematoxylin and eosin [H&E] staining; magnification × 40). b Tumor cells forming small glandular structures (arrowheads); areas of comedo-necrosis are seen (arrows) (H&E; magnification × 100). c Tumor cells immunopositive for carcinoembryonic antigen at the lumen (arrows) (magnification × 400. d Tumor cells immunopositive for epithelial membrane antigen at the lumenal rims (arrows) (magnification × 400)