Primary neuroendocrine differentiated mucinous adenocarcinoma of the vulva: case report and review of the literature.

Only a few cases on mucinous adenocarcinomas of the vulva have been reported. In this study, we present a case of a 75-year-old woman with a tumor in the left major labium. Because biopsy had shown formations of squamous cell carcinoma, radical vulvectomy with bilateral inguinal and femoral lymph node dissection were performed. At that time, histology was interpreted as small-cell, anaplastic carcinoma, with focal epidermoid differentiation. Postoperative radiation therapy was performed. Sixteen months after surgery, the patient presented with bilateral breast carcinomas. Histology showed a scirrhous carcinoma of the left and a medullary carcinoma of the right breast, but no lymph node metastases. Histochemical and immunohistochemical re-examination of the vulvar carcinoma now revealed a mucinous adenocarcinoma with neuroendocrine differentiation. The tumor expressed neuroendocrine markers such as chromogranin A and protein gene-product (PGP) 9.5, as well as peptides of the vasoactive intestinal polypeptide (VIP) family, and serotonin. Histochemical silver stains demonstrated Grimelius argyrophilia and Masson argentaffinity. Because of positive estrogen and progesterone receptor status of both breast cancers, postoperative Tamoxifen therapy was performed. The patient is still alive four years after vulvectomy.