CD274 and non-small cell lung carcinoma: Loss of PD-L1 TPS in NSCLC sections to levels below these prescribing guideline cutoffs occurred for all clones at varying time points, with over half of cases changing from diagnostically positive to diagnostically negative by day 19 for 22C3 (TPS ≥ 1% and ≥50%), day 9 for 28-8 (TPS ≥ 1% and ≥50%), and day 9 for positive and day 19 for strongly positive for E1L3N (Fig. 2).