CDKN1C and cancer: To demonstrate the presence of context-dependent PD-L1 predictive capacity, we developed a PD-L1 predictiveness score (PD-L1 PS) based on a linear regression between CDKN1C and OS PD-L1 predictiveness across cancer types (PD-L1 PS = −0.76 × CDKN1C + 2.81; Supplementary Fig. 6) and bifurcated patients into Predictiveness-High (PH) and Predictiveness-Low (PL) based on the median value of PD-L1 PS.