Clinical significance of the pretreatment C-reactive protein-albumin-lymphocyte (CALLY) index in colorectal cancer patients: a meta-analysis

BACKGROUND: The C-reactive protein-albumin-lymphocyte (CALLY) index, which is devised to evaluate the inflammatory, immune, and nutritional status of patients, has emerged as a potentially valuable prognostic biomarker in diverse malignancies. The aim of this study is to conduct a systematic investigation into the correlation between the pretreatment CALLY index and clinical outcomes in patients with colorectal cancer. METHODS: A comprehensive systematic literature search was carried out using electronic databases, including Web of Science, PubMed, CNKI and Embase. The search spanned from inception to July 1, 2025, with an update on September 20, 2025. The primary endpoints were survival outcomes and postoperative complications, while the secondary outcomes were clinicopathological features. This meta-analysis has been registered with PROSPERO (CRD420251156757). RESULTS: A total of ten studies, involving 7,362 patients with colorectal cancer, were included in the meta-analysis. The pooled findings indicated that patients in the high CALLY group demonstrated significantly better overall survival (Hazard ratio [HR] = 0.62; 95% confidence interval [CI]: 0.53–0.73; I² = 69%), better disease-free survival (HR = 0.58; 95% CI: 0.41–0.81; I² = 84%), and a lower risk of postoperative complications (Odds ratio [OR] = 0.55; 95% CI: 0.38–0.81; I² = 29%) compared to those in the low CALLY group. Moreover, a high CALLY index was significantly associated with a lower percentage of T4 tumors and a lower proportion of poorly differentiated histology. CONCLUSIONS: Our evidence suggests that the pretreatment CALLY index holds potential as a valuable biomarker to predict clinical outcomes for patients with colorectal cancer.