For instance, tumours showing ESN/LGESS and/or leiomyoma-like features with bland nuclei and low mitotic activity could be classified as low-grade KAT6B/A::KANSL1 uterine sarcomas, while tumours showing concurrent monomorphic nuclear atypia (large, sometimes epithelioid, nuclei) and elevated mitotic activity (readily identified mitotic figures) could be classified as high-grade KAT6B/A::KANSL1 uterine sarcomas. Here, KANSL1 is linked to leiomyoma.