High-grade endometrial stromal sarcoma with BCOR rearrangements: clinicopathological analysis of five cases and literature reviews - an extension in understanding of morphological characteristics.

Five cases of FISH verified BCOR rearranged high-grade endometrial stromal sarcoma were retrospectively analyzed. The patient age ranged from 33 to 65 years (median, 48.4 years). Most patients presented with irregular vaginal bleeding (3/5) and uterus mass (2/5). Only one patient developed an abdominal wall metastasis and other patients remained in good condition during the follow-up. Pathological findings revealed that the tumors exhibited morphological diversity in terms of cell shape, arrangement pattern and tumor stroma, compared to previous summarized histology of BCOR rearranged high-grade endometrial stromal sarcoma. Detailed description of such morphology changes expanded our understanding of the histology of BCOR rearranged high-grade endometrial stromal sarcoma. Due to the non-specificity of morphology in such malignancies, molecular testing is needed for confirmation in all patients.