e20575 Background: Baseline hematological parameters have emerged as potential prognostic biomarkers in patients with advanced non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs). In parallel, growing evidence suggests that circadian timing of immunotherapy administration may influence treatment efficacy. However, real-world data evaluating the combined impact of hematological parameters and timing of ICI administration in the first-line setting remain limited. Methods: We performed a retrospective analysis of patients with advanced NSCLC without actionable driver mutations treated at the Vietnam National Cancer Hospital with off-trial first-line platinum-doublet chemotherapy plus pembrolizumab or pembrolizumab monotherapy between June 2018 and June 2025. Baseline hematological parameters, including neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), were collected prior to treatment initiation. NLR was dichotomized at 3 and PLR at 150. Timing of immunotherapy administration was categorized at the patient level based on predominant infusion timing as morning (before 12:00) or afternoon (after 12:00). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method and compared between groups. Results: A total of 225 patients were included, with a median age of 63 years; 83.1% were male, 84.8% had non-squamous histology, and 33.8% had PD-L1 expression ≥50%. Patients with baseline NLR ≤3 demonstrated significantly longer median OS compared with those with NLR >3 (35.7 vs 19.0 months; p = 0.0058), while no significant difference in median PFS was observed (14.0 vs 11.0 months; p = 0.231). Similarly, patients with PLR ≤150 had superior median OS compared with those with PLR >150 (35.7 vs 20.3 months; p = 0.0162), without a significant impact on PFS ( p = 0.306). Patients with predominant morning immunotherapy administration had numerically longer OS (30.1 vs 22.4 months) and PFS (14.0 vs 10.1 months) compared with those with predominant afternoon administration, although these differences did not reach statistical significance (OS p = 0.1276; PFS p = 0.1113). Conclusions: In this real-world cohort of patients with advanced NSCLC treated with first-line immunotherapy, lower baseline NLR and PLR were significantly associated with improved overall survival. Timing of immunotherapy administration showed a favorable numerical trend for morning infusion but did not reach statistical significance. These findings support the prognostic value of readily available hematological biomarkers and suggest that circadian factors may warrant further investigation in prospective studies.
Nguyen et al. (Thu,) studied this question.