Ovarian neuroendocrine carcinoma associated with a mucinous neoplasm.

We describe a rare case of a neuroendocrine carcinoma of the ovary in a 22-year-old woman who presented with abdominal pain and a pelvic mass. Exploratory laparotomy revealed a right ovarian tumor weighing 2100 g. A right salpingo-oophorectomy and an appendectomy were performed. There was no evidence intraoperatively or postoperatively of metastatic disease. Microscopic examination of the ovary revealed solid nests of tumor cells with a neuroendocrine appearance, high mitotic rate, necrosis, and vascular invasion; the tumor was associated with a predominantly borderline mucinous neoplasm with a small focus of mucinous carcinoma. Neuroendocrine differentiation was confirmed by Grimelius stains, immunohistochemical assays (chromogranin), and electron microscopy. The appendix was histologically unremarkable. The patient received a course of chemotherapy; 3 months after completing chemotherapy, she developed multiple liver metastases and died of disease a week later. To our knowledge, this case report is the second one involving a primary neuroendocrine carcinoma of the ovary occurring in association with a mucinous neoplasm. Mixed mucinous and neuroendocrine carcinoma of the ovary may represent a rare neoplasm with extremely aggressive behavior.