Diagnostic Value of Serum Pro-gastrin-releasing Peptide and Neuron-specific Enolase for Small Cell Lung Cancer and Its Influencing Factors

  Objective  To investigate the clinical significance and influencing factors of serum levels of pro-gastrin-releasing peptide (ProGRP) and neuron-specific enolase (NSE) in the diagnosis of small cell lung cancer (SCLC).

  Methods  The levels of serum ProGRP and NSE in 93 SCLC patients (SCLC group), 120 non-small cell lung cancer (NSCLC) patients (NSCLC group), 120 benign pulmonary disease patients (benign disease group), and 90 healthy people (healthy control group) were determined using enzyme-linked immunosorbent assay (ELISA). The potential impacts of the hemolysis in samples and impaired renal function on ProGRP and NSE were tested via electroluminescent and chemiluminescent immunoassay, respectively.

  Results  The serum ProGRP and NSE concentrations were 90.61(11.75-20 020.90)ng/L and 13.18(3.05-201.88)μg/L, respectively, in SCLC group; 13.26(8.54-526.23)ng/L and 5.86(1.80-100.90)μg/L in NSCLC group; 24.65(1.32-802.93)ng/L and 7.22(1.36-174.62)μg/L in benign disease group; and 14.74(4.59-100.86)ng/L and 4.95(1.31-10.58)μg/L in healthy control group. The levels in the SCLC group were significantly different from those in the other three groups (all P < 0.01).The area under the receiver operating characteristic curve of ProGRP was (0.856±0.023) (95% CI: 0.811-0.901). When the cutoff value of ProGRP was set at 46 ng/L, the diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and Youden's index were 64.5%(60/93), 94.2% (311/330), 75.9% (60/79), 90.4% (311/344), and 58.7%, respectively, showing good detection performance. Sample hemolysis seriously improved the detection results of NSE. Patients with impaired renal function had higher ProGRP levels.

  Conclusions  The serum ProGRP and NSE levels are valuable tumor markers for the diagnosis of SCLC. Detection of both markers are particularly useful for the monitoring of SCLC.Sample hemolysis may seriously increase the detected NSE level, whereas impaired renal function may increase the detected ProGRP level.