CEACAM5 and chronic obstructive pulmonary disease: The multivariate analysis showed that presence of COPD (HR 1.619, P = 0.030), old age (HR 1.007, P < 00001), an advanced disease stage (stage III HR 5.513, P < 0.0001; stage IV HR 11.743, P < 0.0001), the squamous cell carcinoma histological subtype (HR 3.106, P < 0.0001), the presence of a cough (HR 2.463, P = 0.001) a higher serum carcinoembryonic antigen level (HR 1.001, P = 0.023) and higher NRL (HR 2.615, P = 0.007) were independent factors that were significantly associated with poorer survival.