Impact of PD-L1 expression on the efficacy of first-line crizotinib in advanced ROS1-rearranged NSCLC.

BACKGROUND:The predictive value of programmed death-ligand 1 (PD-L1) expression for the efficacy of tyrosine kinase inhibitors (TKIs) in patients with advanced ROS1-rearranged non-small cell lung cancer (NSCLC) remains underexplored. This study analyzed patients with advanced NSCLC harboring ROS1 rearrangements who received first-line crizotinib to evaluate the correlation between baseline PD-L1 expression and crizotinib efficacy. METHODS:In this study, the clinical data from 371 patients diagnosed with ROS1-rearranged NSCLC at Shanghai Chest Hospital between November 2017 and December 2022 were reviewed. The patients were categorized into three groups according to the baseline PD-L1 expression: tumor proportion score (TPS) <1%, TPS 1 %-49 %, and TPS≥50 %. The objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS) following first-line crizotinib treatment were measured. RESULTS:A total of 64 patients were included in the analysis, with 16 patients in the TPS<1% group, 22 in the TPS 1 %-49 % group, and 26 in the TPS≥50 % group. The overall DCR was 100 %, and the overall ORR was 76.5 %. The ORRs were 81.2 % (13/16) in the TPS<1% group, 63.6 % (14/22) in the TPS 1 %-49 % group, and 84.6 % (22/26) in the TPS≥50 % group (p = 0.218). The median PFS across all patients was 20.21 months (95 % CI: 15.71-24.71), with a median PFS of 28.96 months (95 % CI: 19.87-38.04) in the TPS<1% group, 17.56 months (95 % CI: 12.25-22.86) in the TPS 1 %-49 % group, and 25.85 months (95 % CI: 18.52-33.17) in the TPS≥50 % group (p = 0.100). The median PFS for patients with CD74 fusion was 18.23 months (95 % CI: 15.24-21.22), while those with non-CD74 fusion exhibited a PFS of 16.49 months (95 % CI: 9.75-23.23) (p = 0.359). CONCLUSION:Patients with advanced ROS1-rearranged NSCLC were found to benefit from first-line crizotinib treatment, irrespective of baseline PD-L1 expression.