Pro-gastrin-releasing peptide (ProGRP), neuron specific enolase (NSE), carcinoembryonic antigen (CEA) and cytokeratin 19-fragments (CYFRA 21-1) in patients with lung cancer in comparison to other lung diseases.

The study presents data comparing the new tumour marker, ProGRP, with the established markers, NSE, CYFRA 21-1 and CEA in the diagnosis of lung cancer. ProGRP as well as NSE have been reported to be useful markers for staging and monitoring treatment in patients with small cell lung cancer (SCLC). In order to determine the differences in the sensitivity and/or specificity particularly with regard to benign lung diseases, the present study investigated ProGRP in comparison to NSE, CEA and CYFRA 21-1 usually used in lung cancer. ProGRP was quantitatively detectable with an ELISA. So far 192 newly-diagnosed lung cancer patients including 51 SCLC have been examined. Served as controls: 124 subjects i.e. 50 patients with pneumoconiosis, 22 patients with obstructive airway diseases, 34 patients with acute inflammatory lung diseases and 18 healthy persons. Significantly elevated tumour marker concentrations were found for ProGRP and NSE in SCLC. At a specificity of 95%, ProGRP and NSE showed comparable sensitivities (68.6% and 74.5%) in SCLC. ProGRP also reached high levels in patients with limited disease status (sensitivity ProGRP: 72.2%, NSE 66.7%). Initial follow-up studies indicated that ProGRP can be used to monitor disease under chemotherapy. In non-small cell lung carcinomas, CYFRA 21-1 was the leading marker with 58.9% sensitivity where ProGRP seldom revealed positive results. ProGRP is a valuable tumour marker for the detection and monitoring of SCLC and a good tool for discriminating NSCLC versus SCLC.