CD274 and non-small cell lung carcinoma: Since the advent of immune therapy (anti-PD-1 and PD-L1) in the NSCLC realm, numerous authors have assessed its impact on the central nervous system (CNS) both as a standalone treatment and in conjunction with chemotherapy within the brain, these innovative drugs with their distinct mode of action posed both a challenge in enhancing the efficacy of existing treatment strategies up to that point.