HALP and SII as blood-based predictors in metastatic small-cell lung cancer

Aims: Small cell lung cancer (SCLC) is an aggressive malignancy with limited survival, underscoring the need for accessible prognostic markers. This study aimed to evaluate the prognostic value of the hemoglobin, albumin, lymphocyte, and platelet (HALP) score and the Systemic Immune-inflammation Index (SII) in patients with SCLC. Methods: We retrospectively analyzed 132 patients diagnosed with metastatic SCLC. Baseline laboratory data were used to calculate HALP and SII scores. Optimal cut-off values were determined by ROC analysis. Survival outcomes were assessed using Kaplan-Meier and Cox regression analyses. Results: The optimal cut-off values were 17.23 for HALP (AUC: 0.611, 95% CI: 0.50-0.72, p=0.04) and 747.27 for SII (AUC: 0.628, p=0.02, 95% CI: 0.52–0.73). High SII was an independent predictor of shorter progression-free survival (PFS) (HR=1.82, 95% CI: 1.02–3.26, p=0.04), but not overall survival (OS). HALP score predicted 6-month survival but showed no significant effect on OS or PFS. Liver (HR=1.72, 95% CI: 1.02-2.90, p=0.04) and brain metastases (HR=1.74, 95% CI: 1.08-2.80, p=0.02) were independent predictors of shorter PFS. Conclusion: SII may serve as a reliable prognostic marker for PFS in SCLC, while HALP showed limited predictive value. Metastatic sites, particularly liver and brain involvement, significantly impact prognosis. Larger, prospective studies are needed to validate these findings.