Serous carcinoma of the endometrium with choriocarcinomatous differentiation: a case report and review of the literature indicate the existence of 2 prognostically relevant tumor types.

Nongestational choriocarcinomas rarely occur outside the gonads or teratomas. We report a serous carcinoma of the endometrium with a choriocarcinomatous component and review of the literature. A 61-year-old woman underwent hysterectomy and bilateral salpingo-oophorectomy for a serous carcinoma with choriocarcinomatous component. Immunohistochemistry showed a strong p53 staining of the serous component and the cytotrophoblastic cells of the choriocarcinomatous component; the syncytiotrophoblast was negative. The initial serum human chorionic gonadotropin (hCG) was 225,000 IU/L. Postoperatively, the patient developed diffuse pulmonary metastatic disease. Despite chemotherapy, the patient died 2 months after initial diagnosis. Abstracting the data from the reported cases and from the literature, it can be assumed that 2 different tumor types exist. The first one is morphologically and clinically more related to the gestational choriocarcinoma with strongly elevated serum hCG levels, early onset of (distant) metastatic disease, and consecutively rapid and often fatal clinical course. The second type presents as an endometrial carcinoma with single syncytiotrophoblast-like cells, associated with low serum hCG, no distant metastatic disease, and, consequently, a better prognosis. The prognostically relevant component for long-time survival in the latter variant is the nontrophoblastic component.