A Case of Small Cell Carcinoma of the Ovary, Hypercalcemic Type Combined with Low-Grade Serous Carcinoma

Abstract

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT), is an extremely rare and deadly cancer with a poor prognosis. Unfortunately, the causes that lead to the development of SCCOHT are unknown. In this study, we present a case in which SCCOHT and low-grade serous carcinoma (LGSC) occurred in the same ovary. The patient, a woman in her 30s, visited the obstetrics and gynecology department for weight loss and abdominal distension. Imaging examinations indicated an ovarian malignancy. Therefore, simple total hysterectomy, bilateral adnexectomy, and omentectomy were performed. The left ovary was enlarged with proliferation of SCCOHT and LGSC. The tumor had metastasized to the right ovary and multiple metastatic dissemination sites were found in the abdominal cavity. This case of combined SCCOHT and LGSC suggests that SCCOHT arises from the dedifferentiation of LGSC.