Endometrial stromal sarcoma: clinicopathological and immunophenotypic study of 16 cases

Purpose Endometrial stromal sarcomas (ESSs) are rare tumors and are divided into two groups: low-grade endometrial stromal sarcoma (ESS-LG) and undifferentiated endometrial sarcoma (UES). The purpose of this study was to compare the clinicopathological features and immunophenotypes of ESS-LG and UES. Methods The authors evaluated 16 patients diagnosed with ESS at the Hyogo Cancer Center, reviewed their files and data, and performed an immunohistochemical study for oncogenic proteins (EGFR, PDGFR-α, and PDGFR-β) and cell cycle regulators (cyclin D1, cyclin E, p16 INK4a , p21 cip1 , p27 kip1 , and p53) to compare ESS-LG and UES using the World Health Organization (WHO) classification. Results Four cases (25 %) were classified as ESS-LGs and 12 (75 %) as UES. Patients with UES had a significantly worse overall survival than did those with ESS-LG ( p = 0.0445). Although no ESS-LGs showed expression of p16 INK4a , 10 of 12 (83 %) UESs showed expression of p16 INK4a . UESs showed a trend toward higher expression of cyclin D1, p21 cip1 , and p53 compared with ESS-LGs. Conclusions Our data emphasize the clinical importance of the WHO classification of ESS. It is of utmost importance to establish a proper classification to increase the consistency of data that may be useful for improving clinical and therapeutic management of patients with ESS.