Immunohistochemical Distinction of Endometrial Stromal Sarcoma and Cellular Leiomyoma

Publisher Website
Google Scholar
Abstract
Distinguishing low grade endometrial stromal sarcoma (ESS) from benign smooth muscle proliferations like cellular leiomyoma (CL) can be problematic; because of differing treatments and prognosis, this distinction is important. The authors tested the hypothesis that low grade ESS could be distinguished from CL by immunohistochemistry using a panel of antibodies that have not previously been used in this setting. Antibodies to calponin, smooth muscle myosin heavy chain (SMM-HC), the Wilms tumor gene product (WT-1), and CD10 were applied to 14 cases of ESS (10 low grade, 4 high grade) and 9 CL. Among low grade ESS, 3 of 10, 3 of 10, 9 of 10, and 10 of 10 were positive for expression of calponin, SMM-HC, WT-1, and CD10, respectively. Of CL, all 9 were positive for calponin, SMM-HC, and WT-1, whereas 3 of 9 marked with antibodies to CD10. Overall, SMM-HC and calponin were expressed strongly in CL but weakly expressed in ESS; the converse was true for CD10. Expression of WT-1 and the reticulin-staining pattern do not discriminate between these two tumors. Antibodies to SMM-HC, CD10, and calponin can reliably distinguish ESS from CL.