Role of a serum‐based biomarker panel in the early diagnosis of lung cancer for a cohort of high‐risk patients

BACKGROUND This study applied a combined cancer biomarker panel to clinically identify small cell lung cancer (SCLC) and non–small cell lung cancer (NSCLC) in a high‐risk population. METHODS The serum levels of 4 biomarkers (progastrin‐releasing peptide [ProGRP], carcinoembryonic antigen [CEA], squamous cell carcinoma antigen [SCC], and cytokeratin 19 fragment [CYFRA21‐1]) were determined in 153 patients with a high risk of lung cancer (12 with a new diagnosis of SCLC, 52 with NSCLC, and 89 without lung cancer). Information about diagnosis delays was collected through interviews of all participants. RESULTS Significantly higher serum levels of ProGRP ( P  < .0001) were found among the SCLC patients versus the rest of the population. A receiver operating characteristic curve analysis established the cutoff values of ProGRP, CEA, SCC, and CYFRA21‐1 as 300 pg/mL, 7.3 ng/mL, 3 ng/mL, and 6.5 ng/mL, respectively. The sensitivity and specificity of ProGRP in diagnosing SCLC were 75% and 100%, respectively. Among the 14 lung cancer patients with a false‐negative computed tomography (CT) result, the diagnostic panel detected 8 additional cancers. CONCLUSIONS This panel increased the diagnostic specificity for high‐risk subjects (those with renal failure being excluded), and auxiliary to a CT scan, it increased the sensitivity for patients with lung cancer. These results might be applied to shorten the diagnosis delay at health care institutions in China. Cancer 2015;121:3113‐21. © 2015 American Cancer Society .