Meta-analysis of preoperative CALLY index for predicting the prognosis of cancer

This study aims to evaluate the predictive value of the CALLY index in cancer prognosis via systematic review and meta-analysis. PubMed, Web of Science, Embase, and Cochrane were searched up to November 2024. Study quality was evaluated using the Newcastle-Ottawa Scale (NOS), and meta-analysis was performed with STATA 17.0. Among 21 cohort studies,the findings indicated that, regarding overall survival (OS), a low CALLY index was correlated with a 113% elevated likelihood of all-cause mortality compared to those with a higher CALLY index (risk ratio [RR] = 0.47, 95% confidence intervals [95%CI]: 0.42–0.53). An 85% elevated risk of disease-free survival (DFS) and relapse-free survival (RFS) was observed in individuals with a low CALLY index (pooled RR = 0.54, 95%CI: 0.46–0.63). Moreover, a lower CALLY index was correlated with a significantly greater tumor burden (standardized mean difference (SMD) = -0.64, 95%CI: −0.76–0.52). The stage-specific analysis demonstrated that a low CALLY index significantly increased the risk of cancer progression by 54% in individuals at stage II (RR = 0.65, 95%CI: 0.43–0.98) and by 67% in individuals at stage III (RR = 0.60, 95%CI: 0.43–0.86). The CALLY index independently predicts adverse cancer outcomes.