The prognostic value of the lung immune prognostic index in patients with urological cancers: a systematic review and meta-analysis

Background – The Lung Immune Prognostic Index (LIPI), derived from the derived neutrophil-to-lymphocyte ratio and lactate dehydrogenase, integrates systemic inflammation and tumour burden. Its prognostic utility in urological malignancies has not been comprehensively quantified. Methods – We conducted a systematic review and meta-analysis in accordance with PRISMA and a prospectively registered protocol. PubMed, Embase, and the Cochrane Library were searched through October 2025. Eligible cohort studies or trials evaluated associations between LIPI categories (good/intermediate/poor) and survival outcomes in renal cell carcinoma, urothelial carcinoma, and prostate cancer. Random-effects models were fitted using REML with Hartung-Knapp adjustment. When hazard ratios (HRs) were not directly reported, we reconstructed pseudo-individual patient data from Kaplan-Meier curves to estimate HRs. Results – Thirteen studies (19 independent cohorts; 5, 304 patients) were included. Compared with good LIPI, intermediate LIPI was associated with worse overall survival (OS) (HR 1.73, 95% CI 1.52-1.98) and shorter progression-free survival (PFS; including disease-free survival after surgery where applicable) (HR 1.39, 95% CI 1.13-1.71). Poor LIPI showed a stronger association with inferior OS (HR 3.73, 95% CI 2.95-4.71) and PFS (HR 2.69, 95% CI 1.96-3.70). Prognostic gradients were generally consistent across tumour types and treatment settings, including immune checkpoint inhibitor-treated cohorts. Conclusions – LIPI is a readily available biomarker that provides robust risk stratification across major urological cancers and may support treatment planning and trial stratification. Systematic Review Registration – https://www.crd.york.ac.uk/PROSPERO/view/CRD420251235082, identifier CRD420251235082.