HIGH-STAGE ENDOMETRIOID CARCINOMA OF THE OVARY - PROGNOSTIC-SIGNIFICANCE OF PURE VERSUS MIXED HISTOLOGIC TYPES

We retrospectively reviewed 80 cases of endometrioid carcinoma of the ovary: 68 pure endometrioid tumors and 12 predominantly endometrioid c arcinomas (>50%) mixed with either papillary serous or undifferentiate d carcinoma. Each group had 11 cases of stage III or IV tumors, which were studied to determine whether the overall prognosis was affected b y grade, histology, number of mitoses, residual tumor after surgery, a nd patient's age. Prognosis was significantly affected only by a mixed histologic pattern. The 5- and 10-year survival rates and the median survival time for pure endometrioid carcinomas were much better than t hose for mixed endometrioid carcinomas (63% and 45% and >86 months ver sus 8% and 0% and 18 months, respectively). Recurrent tumors in cases of mixed endometrioid carcinoma were pure serous or undifferentiated c arcinomas, whereas those in cases of pure endometrioid carcinoma were either endometrioid or high-grade carcinoma. Our results show that the presence of even a small component of serous or undifferentiated carc inoma in an otherwise predominantly endometrioid carcinoma significant ly affects the prognosis. Thus pathologists should thoroughly sample a ll endometrioid carcinomas, especially high-stage tumors, to ensure th at no serous or undifferentiated component is present.