The ESMO (European Society of Medical Oncology) and NCCN (National Comprehensive Cancer Network) guidelines propose that anti-PD-1/PD-L1 agents are recommended as first-line monotherapy only when the expression of PD-L1 in NSCLC patients is ≥50% and there are no other operable molecular markers. The gene discussed is CD274; the disease is non-small cell lung carcinoma.