Abstract / Summary
Background Inflammatory markers have been reported to be associated with outcomes in non-small cell lung cancer (NSCLC). However, whether early treatment-related changes in these markers provide additional prognostic information remains unclear. This study evaluated the association between dynamic changes in peripheral blood inflammatory markers during chemotherapy and survival outcomes in patients with NSCLC. Methods We retrospectively analyzed 479 patients with NSCLC who received chemotherapy. Changes in lymphocyte, platelet, and neutrophil counts, as well as the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (PLR), were calculated as absolute differences (D-values) between baseline measurements obtained before the first chemotherapy session and post-chemotherapy measurements obtained within 7 days after the first session. Overall survival (OS) was assessed using Kaplan–Meier analysis and Cox proportional hazards models. Additional Cox models were used to examine the association of PLR D-value with OS after accounting for baseline PLR and clinical covariates. A prognostic nomogram was constructed as an exploratory risk-estimation model. Results Greater changes in the evaluated hematological markers were associated with shorter OS in Kaplan–Meier analysis. In the primary multivariable Cox regression, high PLR D-value was associated with shorter OS (hazard ratio, 1.422; 95% confidence interval, 1.001–2.020; P = 0.049), together with sex, anemia status, and tumor extent. After adjustment for baseline PLR and clinical covariates, however, PLR D-value was no longer significantly associated with OS when analyzed either as a continuous variable (HR per 50-unit increase, 1.010; 95% CI, 0.947–1.078; P = 0.762) or using the original high/low classification (HR, 1.31; 95% CI, 0.91–1.89; P = 0.145). The nomogram had an apparent C-index of 0.630 and an optimism-corrected C-index of 0.618 after 1,000 bootstrap resamples. Conclusions Greater changes in PLR during chemotherapy were associated with shorter OS in the primary categorical analysis. However, this association was attenuated after baseline PLR and clinical factors were taken into account, indicating that the additional prognostic contribution of PLR D-value may be limited. The nomogram should be considered exploratory and requires external validation before clinical application.