Stem cell factor and granulocyte-macrophage-colony stimulating factor as candidates for tumour markers for non-small-cell lung cancer

We have investigated the serum level of stem cell factor (SCF) and granuloc yte-macrophage-colony stimulating factor (GM-CSF) in relation to a control group and commonly accepted tumour markers, such as carcinoembryonic antige n (CEA) and cytokeratin fragment 19 (CYFRA 21-1). Additionally, we have def ined the diagnostic sensitivity, specificity, positive predictive value, ne gative predictive value and receiver-operating characteristics (ROC) curve of SCF and GM-CSF in non-small-cell lung cancer (NSCLC). The serum levels o f cytokines were measured in 50 patients with NSCLC and in 20 healthy subje cts. SCF and GM-CSF were determined using enzyme-linked immunosorbent assay (ELISA), CYFRA 21-1 was measured by radioimmunoassay and CEA by microparti cle enzyme immunoassay. There were significant increases in circulating SCF and GM-CSF in the lung cancer patients compared to the control group. The diagnostic sensitivity of GM-CSF was higher (70 %) than the sensitivity of CEA (62 %) and CYFRA 21-1 (51 %). The diagnostic specificity of GM-CSF was lower (65 %) than SCF specificity (70 %), but the GM-CSF predictive values were higher in relation to the predictive values of SCF. These results sugg est a potential role of SCF and GM-CSF as tumour markers for NSCLC.