Uterus, high‐grade endometrial stromal sarcoma

This high‐grade malignant tumour of endometrial stromal derivation is rare. In many cases, it is associated with a distinct chromosomal translocation: t(10;17), resulting in the YWHAE‐FAM22 fusion gene. It is characterized by a mixture of high‐grade round cells and low‐grade spindle cell components. There is a delicate capillary network. Mitoses are numerous. This biopsy represents only a small sampling of the larger mass (see link to a slide from a diagnostic biopsy in the Related Content section).

The tumour is immunohistochemically positive for CD10 and cyclin‐D1, negative for caldesmon (see attached supplementary images in the Related Content section).