Multivariate Cox regression analysis indicated that ECOG PS (HR = 3.956; P = 0.001), serum DKK1 level (HR = 1.675; P = 0.029), number of bone metastases (HR = 1.904; P = 0.004) and metastatic pattern (HR = 1.283; P = 0.022) were independent prognostic factors for overall survival in NSCLC patients with bone metastases (Table 5). This evidence concerns the gene DKK1 and non-small cell lung carcinoma.