CEACAM5 and non-small cell lung carcinoma: In non-small cell lung carcinoma, Okada et al. analyzed 1000 patients with clinical stage I non-small cell lung carcinoma and found that preoperative serum carcinoembryonic antigen (CEA) levels were an independent prognostic factor [6] and Kinoshita et al. also reported high-grade serum CEA levels, lymphatic permeation, and vascular invasion were independent prognostic factors [7].