Prognostic impact of tumour burden score on colorectal cancer liver metastasis survival following resection: a meta-analysis

Abstract Purpose Tumour burden score (TBS) shows promise for colorectal cancer liver metastasis (CRLM) prognostication, yet conflicting evidence has stalled its adoption. Our study evaluated the association between TBS and long-term outcomes after hepatectomy using a diagnostic meta-analysis workflow. Methods We searched seven databases through September 30, 2025, for retrospective cohorts supplying hazard ratios for TBS-based survival. Random-effects synthesis with Hartung–Knapp adjustment was used; heterogeneity was explored via leave-one-out analyses. Data integrity was verified with subgroup analysis, sensitivity analyses and trim-and-fill publication-bias assessment; GRADE rated certainty. Results Thirteen cohorts ( N = 5,100) were pooled. High TBS was linked to shorter overall survival (OS) (HR = 1.57; 95% CI: 1.36–1.81; k = 11); recurrence-free survival or disease-free survival in four cohorts yielded HR = 1.61 (95% CI: 1.32–1.96). One study with biologically implausible nonlinear hazards drove heterogeneity ( I 2 = 27.4%); its exclusion removed inconsistency ( I 2 = 3.5%) and refined the OS HR to 1.65 (95% CI: 1.40–1.96). The subgroup analysis confirmed that the adverse prognosis of TBS was independent of regional distribution, publication year, time span, study design, sample size, analysis mode, and TBS cut-off value stratification ( p for interaction > 0.05). The fail-safe N (440) and the trimming method suggested that the core conclusion was robust to potential publication bias. Conclusion TBS is an independent prognostic marker for post-hepatectomy CRLM survival. High TBS confers a 65% mortality hazard, warranting its inclusion in multidisciplinary risk-stratification algorithms.