RB1 and Wilson disease: Of note, considering that 16 patients fitting the 4 biomarker conditions (overexpression of CDK4, no overexpression of CDKN2A, and no pathogenic mutations in RB1 or TP53) exhibited improved outcome with a median PFS of 5.67 months and a median OS of 15 months, this 4-biomarker set should be validated in prospective studies testing CDK4/6 inhibitors in sarcomas other than WD/DD-LPS.