Prognostic Value of the Lung Immune Prognostic Index and an ECOG-Albumin-LIPI Nomogram in Metastatic NSCLC Patients Treated with Second- or Third-Line Nivolumab.

Background/Objectives: Clinical outcomes with immune checkpoint inhibitors (ICIs), such as nivolumab, vary among patients with metastatic non-small cell lung cancer (NSCLC). The Lung Immune Prognostic Index (LIPI) may help stratify prognosis. This study evaluated the prognostic significance of LIPI in patients receiving second- or third-line nivolumab and developed a nomogram for individualized survival estimation. Methods: This single-center retrospective study included 142 patients with metastatic NSCLC who received second- or third-line nivolumab between February 2022 and December 2024, after progression on platinum-based chemotherapy. LIPI was calculated from baseline values obtained within 14 days before nivolumab initiation, based on a derived neutrophil-to-lymphocyte ratio (dNLR) > 3 and lactate dehydrogenase (LDH) > 225 U/L (institutional upper limit of normal), classifying patients as good-, intermediate-, or poor-risk (0, 1, or 2 factors, respectively). Overall survival (OS) and progression-free survival (PFS) were estimated by the Kaplan-Meier method; independent prognostic factors were assessed by multivariable Cox regression, and a prognostic nomogram combining ECOG performance status, serum albumin, and LIPI was developed and internally validated. Results: By LIPI, 34.5%, 45.1%, and 20.4% of patients were at good, intermediate, and poor risk, respectively. Objective response and disease control rates were 29.6% and 55.6%. Median OS and PFS were 19.3/8.0/3.1 and 8.6/3.1/2.5 months across good, intermediate, and poor LIPI groups (log-rank p < 0.001). In multivariable analysis, ECOG 2 (hazard ratio [HR], 4.94), albumin per 1 g/dL (HR 0.27), and poor versus good LIPI (HR 3.74) were independently associated with OS. A nomogram combining these three factors showed acceptable discrimination (optimism-corrected Harrell C-statistic 0.742). Conclusions: LIPI was independently associated with prognosis in this cohort. Combining LIPI with ECOG and albumin may aid individualized risk assessment, pending external validation.