The highest CEACAM6 expression was found in moderately-differentiated adenocarcinoma (7.8 ± 0.4) > well-differentiated adenocarcinoma (7.3 ± 1.1) = bronchioalveolar (7.2 ± 0.8) > poorly-differentiated adenocarcinoma (6.8 ± 1.0) > small-cell (5.5 ± 0.7) > well-differentiated squamous (5.2 ± 1.0) > moderately-differentiated squamous cancer (4.9 ± 1.1). This evidence concerns the gene CEACAM6 and adenocarcinoma.