In two different studies that enrolled 29 and 60 evaluable advanced WD/DD-LPS patients, palbociclib was prescribed at 200 mg per day, 2 weeks on and one week off, and 125 mg per day, 3 weeks on and 1 week off, respectively.16,29 Both trials reported an identical median PFS of 4.2 months that was superimposable to our study, reinforcing the idea that CDK4 overexpression was a reasonable strategy of biomarker selection for CDK4/6 inhibition in sarcoma. This evidence concerns the gene CDK4 and Wilson disease.