Is neoadjuvant immunotherapy necessary in patients with programmed death ligand 1 expression-negative resectable non-small cell lung cancer? A systematic review and meta-analysis

Abstract

ObjectivesThe aim of this study was to investigate the clinical benefit and necessity of neoadjuvant programmed cell death (or ligand) (PD-(L)1) blockades in resectable non-small cell lung cancer (NSCLC) patients with negative PD-L1 expression. Materials and methodsRandomized control trials (RCTs) that compared event-free survival (EFS), overall survival (OS), major pathological response (MPR), and/or pathological complete response (pCR) between neoadjuvant chemo-immunotherapy (nCIT) and neoadjuvant chemotherapy (nCT) for patients with resectable NSCLC stratified by PD-L1 expression were eligible for inclusion in the study. Data regarding the pathological response and EFS were evaluated by the odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) using random and fixed models. ResultsA total of six RCTs involving 3,194 patients with resectable NSCLC with or without neoadjuvant immunotherapy were included. Compared with nCT alone, nCIT significantly improved pCR (18.3 % vs. 3.0 %; OR, 5.64; 95 % CI, 3.22–9.89; P < 0.001), MPR (38.9 % vs. 15.5 %; OR, 3.57; 95 % CI, 2.10–6.05; P < 0.001), and EFS (HR, 0.75; 95 % CI, 0.62–0.90; P = 0.002) in PD-L1 <1 % NSCLC patients. In addition, PD-L1 ≥1 % was associated with higher rates of pCR (32.8 % vs. 18.3 %; OR, 2.28; 95 % CI, 1.40–3.73; P = 0.001) and MPR (53.9 % vs. 38.9 %; OR, 1.84; 95 % CI, 1.22–2.79; P = 004) and longer EFS (HR, 0.44 vs. 0.75) in the setting of nCIT compared with PD-L1 <1 %. nCIT improved only OS in NSCLC patients with PD-L1 ≥1 % but not in patients with PD-L1 <1 %. ConclusionsThe use of nCIT should be recommended for resectable NSCLC patients with negative PD-L1 expression, as nCIT significantly improved the pathological response and EFS in these patients. The benefit to PD-L1-negative patients treated with nCIT on OS remains to be validated.