In the multivariate Cox regression analysis of DFS, the result showed the same independent prognostic factors namely pT stage (P = 0.036), pN stage (P < 0.001), metastasis (P = 0.003) and serum CA724 (P = 0.005) for CRC patients with normal serum CEA levels. The gene discussed is CEACAM5; the disease is colorectal carcinoma.