To evaluate the proportion of patient thyroid tumors that would be potentially responsive or intrinsically resistant to CDK4/6 inhibition, we determined the CDK4 modification profile and the presence of activated T172-phosphorylated CDK4 from a cohort of fresh-frozen samples (n=98) representative of the different subtypes of thyroid tumors (Figure 1A, Supplementary Figure S1 and Table S3). The gene discussed is CDK4; the disease is thyroid tumor.