A proof-of-principle study from the Integrative Analysis of Lung Cancer Etiology and Risk (INTEGRAL) Consortium showed that a panel of four circulating protein biomarkers (CA125, CEA, CYFRA 21–1 and Pro-SFTPB) could be used to identify high-risk individuals for lung cancer screening, demonstrating an AUC of 0.83 (30). The gene discussed is CEACAM5; the disease is lung cancer.