Prognostic Value of C-Reactive Protein-to-Lymphocyte Ratio in Combined Immunotherapy and Chemotherapy for Small Cell Lung Cancer

Inflammatory indexes are emerging as sensible prognostic factors for small cell lung cancer (SCLC). However, the prognostic value of dynamic C-reactive protein-to-lymphocyte ratio (CLR) in SCLC patients treated with chemoimmunotherapy remains unclear. This retrospective study investigated 88 SCLC patients who underwent chemoimmunotherapy between January 1st, 2020 and December 12th 2022. We examined the association between CLR and prognostic outcomes after chemoimmunotherapy. The associations between objective response rate (ORR), progression-free survival (PFS) with changes in blood indicators were also analyzed. Patients with decreased CLR had significantly higher ORR, with odds ratios of 3.91 (P<0.05) and 3.19 (P<0.05) in univariate and multivariate logistic regression analyses, respectively. Kaplan-Meier analysis showed that decreased CLR was associated with prolonged PFS (P=0.02). Additionally, a CLR higher than 2.47 after treatment was associated with poor survival in both univariate and multivariate analyses. Dynamic CLR can serve as a potential biomarker for predicting the prognosis of SCLC patients treated with chemoimmunotherapy. Reduction of CLR after chemoimmunotherapy is associated with a significantly higher ORR and improved PFS.