Abstract
Background : Endometrial stromal sarcoma is a rare tumor. We report a case of undifferentiated endometrial sarcoma, in which peritoneal cytology at the intraoperative consultation revealed atypical epithelioid cells.
Case : A 45-year-old woman presented with irregular vaginal bleeding and was detected to have a uterine myoma. MRI revealed an irregular polypoidal mass lesion in the anterior wall of the uterine body. Therefore, total hysterectomy with bilateral salpingo-oophorectomy was performed. Intraoperative peritoneal cytology showed small atypical cells with an epithelioid pattern of nuclear molding and cannibalism. In the imprint cytology of the resected tumor, small atypical cells were observed in a perivascular arrangement, with numerous mitoses. Immunocytochemically, the atypical cells both in the ascitic fluid and the resected tumor were positive for CD10 and vimentin, but negative for smooth muscle cell markers and neuroendocrine markers. Based on the immunocytochemical and histopathologic findings, the tumor was diagnosed as an undifferentiated endometrial sarcoma.
Conclusion : In conclusion, a uterine body tumor that resembled small cell carcinoma in intraperitoneal fluid cytology was diagnosed as undifferentiated endometrial sarcoma. Extensive morphological analysis as well as immunocytochemical analysis with a panel of immune markers, including CD10 and vimentin, may be necessary for arriving at the histopathological diagnosis of undifferentiated endometrial sarcoma.
