CEACAM5 and colorectal carcinoma: However, the multivariate Cox’s analysis revealed that neither chitinase activity [hazard ratio (HR), 1.069; 95% confidence interval (CI), 0.671–1.701; P = 0.780] nor CEA level (HR, 1.276; 95% CI; 0.788–2.064; P = 0.322) was an independent prognostic factor of OS in patients with CRC (Additional file 1: Table S2).