A Novel Tool for Predicting Outcomes after Immune Checkpoint Inhibitors Therapy in Patients with Lung Cancer

Background: The development of immune checkpoint inhibitors (ICI) has resulted in a shift in the treatment of lung cancer (LC); however, biomarkers of clinical efficacy have not been fully validated. In this study, a novel nomogram with immune factors was used for monitoring the response to ICI therapy. Methods: Patients with LC who received programmed cell death 1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitor treatment were included in this analysis. The immune biomarkers and clinicopathological characteristics at baseline were used to estimate the tumor response. The nomogram was based on the factors determined by univariate and multivariate Cox hazard analyses. The C-index and calibration curve were used to determine the predictive accuracy and discriminative ability of the nomogram. Overall survival (OS) was estimated using the Kaplan–Meier method. Results: Patients with lung metastasis (P=0.010), higher baseline neutrophil–lymphocyte ratio (P<0.001), lower baseline lymphocyte–monocyte ratio (P=0.019), and higher CD3+CD8+ T cell count (P=0.009) were significantly related to tumor response. The above biomarkers were contained into the nomogram. The calibration plot for the probability of OS showed an optimal agreement between the actual observation and prediction by the nomogram at 3 or 5 years after therapy. The C-index of the nomogram for the prediction of OS was 0.804 (95% confidence interval [CI]: 0.739–0.869). Decision curve analysis demonstrated that the nomogram was clinically useful. Moreover, patients were divided into two distinct risk groups according to the OS determined by the nomogram: low-risk group (OS: 17.27 months, 95% CI: 14.75–19.78) and high-risk group (OS: 6.11 months, 95% CI: 3.57–8.65). Conclusions: A nomogram constructed using the lung metastasis baseline neutrophil–lymphocyte ratio, lymphocyte–monocyte ratio, and CD3+CD8+ T cells count could be used to monitor and predict clinical benefit and prognosis in patients with LC during ICI therapy. Funding Statement: There was no funding in our study. Declaration of Interests: The authors declare that they have no conflict of interest. Ethics Approval Statement: All patients provided written informed consent. The Institute Research Ethics Committee of the Sun Yat-Sen University Cancer Center approved this study.