The Zero Childhood Cancer Program reported that data on 18 EWS patients (out of 252 pediatric and AYA high-risk cancer patients who were enrolled in the study) demonstrated the homozygous deletion of CDKN2A/B as a potential biomarker of therapeutic response to CDK4/6 inhibition in three of the EWS patients. The gene discussed is CDKN2A; the disease is childhood malignant neoplasm.