Twenty-two of 33 lung adenocarcinomas (67%) analyzed in our cohort demonstrated CEACAM5 expression by immunohistochemistry, and glycoprotein expression was largely detected in the tumor core itself rather than adjacent normal tissue, which is significant in developing targeted tracers to avoid false positivity (eFigures 1 and 2 and eTable 1 in Supplement 2). This evidence concerns the gene CEACAM5 and lung adenocarcinoma.