Ciliated Carcinoma of the Endometrium

We report a case of ciliated carcinoma of the endometrium in a 55-yr-old woman with stromal hyperthecosis of the ovaries. The patient presented with postmenopausal uterine bleeding and an endometrial curetting revealed an atypical epithelial proliferation that met the criteria for endometrioid adenocarcinoma notwithstanding an abundance of ciliated cells. Cilia were present not only within typical endometrioid glands but also within microacini of quasi-solid areas as well as inside intracytoplasmic vacuoles. The subsequent hysterectomy specimen demonstrated a well-differentiated adenocarcinoma of the endometrium with a predominance of neoplastic glands lined by ciliated epithelial cells, thus confirming the initial suspicion for ciliated carcinoma. Since the first description of ciliated adenocarcinoma of the endometrium in 1983, only a handful of additional cases have been reported in the literature. We review the spectrum of histologic presentations of this endometrial neoplasm and elaborate on its distinction from cilia-bearing mimickers and its histogenesis.