Ciliated Carcinoma—A Variant of Endometrial Adenocarcinoma

Summary Ten examples of endometrial adenocarcinoma composed predominantly of ciliated cells were studied. Four of these neoplasms were examined ultrastructurally to confirm the presence of cilia. Hysterectomy was the treatment for all 10 patients; 4 patients received intracavitary radiation prior to surgery. All 10 of the resected uteri contained residual ciliated adenocarcinoma, and in five ciliated carcinoma invaded the myometrium. A microscopic focus of endometrioid carcinoma, thought to be a second simultaneous primary neoplasm, was present in the ovary of one of the patients. Although ciliated cells are almost always limited to benign endometrial proliferations, this study clearly demonstrates that rare carcinomas, some of which invade the myometrium, are composed of ciliated cells. The light microscopic appearance of these rare ciliated carcinomas is sufficiently distinctive to permit their recognition.