The circulating proteins CYFRA 21-1 (cytokeratin fragment 21-1) and CEA (carcinoembryonic antigen), which are among the earliest biomarker candidates for NSCLC, have been examined in several prior studies with the outcome that elevated plasma levels of these circulating proteins show a trend towards a poorer prognosis [33–38]. The gene discussed is CEACAM5; the disease is non-small cell lung carcinoma.