Association between alkaline phosphatase levels and mortality in Chinese patients with colorectal cancer with liver metastases: a retrospective cohort study

Background: Alkaline phosphatase (ALP) is a potential cancer biomarker. However, its prognostic value in patients with colorectal liver metastasis remains unclear.Objectives: This study aimed to investigate the association between ALP levels and mortality risk in patients with colorectal liver metastases (CRLM), providing insights for enhancing prognostic assessments.Design: Retrospective cohort study.Methods: This study included 195 patients with CRLM from a single centre in China. ALP level was the primary exposure variable, with demographic, clinical and pathological factors serving as covariates. Multivariate Cox regression analyses were used to evaluate the impact of ALP on mortality over a 4-year follow-up period. Covariates included the number of liver metastases, T stage, N stage, chemotherapy, tumour location, primary surgery, topical treatment, apolipoprotein A1, targeted therapy, tumour type, CA-199 levels, metastatic surgery, sex, Karnofsky Performance Status and age.Results: Of 195 enrolled patients, 134 (68.72%) were male, and 61 (31.28%) were female, with ages ranging from January 2008 to December 2019. A total of 147 patients (76.96%) were diagnosed with left hemicolon cancer and 44 (23.04%) with right hemicolon cancer. After adjusting for the covariates, elevated ALP levels were significantly associated with an increased risk of mortality (hazard ratio = 1.24, 95% confidence interval: 1.08-1.43, p = 0.0029). Sensitivity analyses confirmed the robustness of these findings, reinforcing the association across different analytical approaches.Conclusion: ALP level is a valuable prognostic indicator in patients with CRLM. Integrating ALP measurement into clinical practice may enhance risk stratification and patient management. Future research should explore the role of ALP in broader populations and explore its implications for treatment strategies.