Small cell carcinoma of the endometrium: a clinicopathological and immunohistochemical study.

OBJECTIVE To investigate both clinicopathological and immunohistochemical characteristics of small cell carcinoma (SCC) of the endometrium, and to explore the diagnosis, treatment and prognosis of the disease. METHODS A retrospective analysis was performed on clinicopathological data of a patient with SCC of the endometrium in our hospital, who underwent comprehensive surgery of radical hysterectomy, bilateral adnexectomy, pelvic lymphadenectomy, omentectomy, appendectomy, and bilateral ovarian vein ligation. Paraffin blocks of formaldehyde-fixed tumor tissue were cut and stained for histological and immunohistochemical studies. RESULTS microscopic examination showed clusters of small-sized cells with scant cytoplasm, hyperchromatic nuclei and high mitotic activity. The patient was classified as endometrial SCC stage Ib according to the clinical staging of the International Federation of Gynecology and Obstetrics (FIGO). Immunohistochemical tests revealed positive staining for synaptophysin (Syn) and CD56, and the proliferation rate measured with the proliferative marker (Ki67) was approximately 70 percent of tumour cells. The patient was given 4 sessions of postoperative chemotherapy. Tumor markers were within normal range during follow-up examinations, and the patient had survived tumor free for two years. CONCLUSION Primary SCC of the endometrium is extremely rare, and is reported to have a strong invasiveness and a poor prognosis. Immunohistochemistry technique is an important tool for clinical diagnosis of the disease. Comprehensive treatments composed of surgery, radiotherapy and chemotherapy may improve the prognosis.