Original researchRisk factors for the development of metachronous bone metastasis in colorectal cancer patients after curative resection

•Most colorectal cancer patients with bone metastasis have other metastases at the same time.•The value of PET-CT in colorectal cancer patients' follow-up is still controversial.•Tumor location and lymph node involvement are independent risk factors for the development of bone metastasis.

ObjectiveMetachronous bone metastasis (MBM) occurs in 6-10% of colorectal cancer (CRC) patients following surgical treatment. The aim of this study is to determine the risk factors affecting the development of MBM in CRC patients following curative resection.MethodClinical and pathological records of 516 CRC patients who underwent curative resection were retrospectively studied. The association between clinicopathological variables and development of MBM was investigated using univariate and multivariate analyses.ResultThe incidence of MBM was 6.0% and the median time of developing MBM was 15 (range, 1-89) months. Univariate analysis identified that lymph node involvement (p = 0.001), tumor stage (p = 0.020) and tumor location (p = 0.015) were significantly correlated with development of MBM. Multivariate analyses showed tumor location (p = 0.039) and lymph node involvement (p = 0.003) were independent risk factors contributing to the occurrence of MBM.ConclusionThis study indicated that tumor location and lymph node involvement were independent risk factors for development of MBM in CRC patients after curative resection.