This meta-analysis evaluates the prognostic significance of the Prognostic Nutritional Index (PNI) in colorectal cancer (CRC) patients, focusing on overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS). We conducted a comprehensive literature search across PubMed, Embase, Web of Science, and CNKI. Observational studies reporting hazard ratios (HRs) with 95% confidence intervals (CIs) for survival outcomes based on PNI were included. Pooled HRs were calculated using random-effects models. Heterogeneity, sensitivity, and publication bias were evaluated, and subgroup analyses were performed by region, follow-up duration, and tumor stage. A total of 43 studies comprising 19,214 CRC patients were included the meta-analysis. 36 studies with 18,231 patients reported the prognostic value of PNI on the OS of CRC, and the pooled HR was 1.89 (95% CI: 1.70–2.10, P < 0.001). This association remained robust across sensitivity analyses, suggesting PNI as a reliable biomarker for risk stratification. Moderate heterogeneity (I2 = 32.9%) was observed, which subgroup analyses attributed to study region, follow-up duration, and inclusion criteria for CRC stages. Non-Asian cohorts, studies with shorter follow-up or partial staging and high cut-off value of PNI exhibited reduced heterogeneity. Eleven studies with 5,181 patients reported the prognostic value for DFS, and the pooled HR was 1.31 (95% CI: 0.84–2.03). Nine studies with 2,856 patients were for PFS, and the pooled HR was 1.15 (95% CI: 0.78–1.72), neither reaching statistical significance. Significant heterogeneity was noted for both DFS and PFS across the studies. This meta-analysis demonstrates that a low PNI is a robust predictor of poor overall survival in colorectal cancer, particularly in Asian populations and across diverse disease stages. While its prognostic value for DFS and PFS remains uncertain.
Xu et al. (Tue,) studied this question.