Value of tumour and inflammatory markers in lung cancer

The aim of this study was to evaluate the individual diagnostic utility of tumour and inflammatory markers in patients with different pulmonary diseases. The usefulness of neuron-specific enolase (NSE), carcino-embryonic antigen (CEA), serum pro-gastrin releasing peptide (ProGRP) and CYFRA 21-1, as tumour markers, and C-reactive protein (CRP) and tumour necrosis factor-alpha (TNFalpha) as inflammatory markers for diagnosis, treatment and monitoring of patients with different pulmonary afflictions was investigated. Eighty healthy individuals were also included. Serum samples were also obtained from 20 patients suffering from bronchitis, 20 with lung fibrosis and 30 with sarcoidosis. Moreover, serum marker levels were analyzed in 139 patients with different pulmonary malignancies: 29 patients with adenocarcinoma, 30 patients with squamous cell carcinoma, 80 patients with small cell lung cancer (SCLC). All tumour markers showed significantly elevated values in malignant diseases. The levels of ProGRP in patients with benign diseases were significantly higher than those in the healthy group (35.4 +/- 6.6 compared with 21.3 +/- 9.2 pg/ml respectively). The serum ProGRP levels were elevated in SCLC patients (1673.9 +/- 706 pg/ml). The elevation was significantly higher than that of the benign reference group. The acute phase response had a wide range in patients with malignant tumours. Serum CRP levels were significantly higher in patients with SCLC (38.5 +/- 7.6 mg/dl) than in the benign reference group. In conclusion, when serum tumour markers are abnormally elevated in patients with lung cancer, CEA, CYFRA 21-1, NSE and ProGRP are useful clinical markers, good indicators of disease extent and may have important prognostic value. In particular, NSE and ProGRP have a very high sensitivity for SCLC detection.