Serum cytokines and tumour markers in patients with non-small cell carcinoma of the lung. 
We compared the serum levels of several cytokines with established tumour markers in 24 patients with non-small cell lung cancer (NSCLC) and 31 patients with benign lung disease (BLD).  Cytokine levels were measured using in-house double determinant sandwich ELISAs and tumour markers by a variety of established techniques.  There was no correlation between serum cytokines and expression of cytokeratins 18 and 19, MUCI and carcinoembryonic antigen.  While no significant difference was observed in any of the cytokines between patients with NSCLC and BLD, patients with metastatic tumour had a significantly higher level of serum tumour necrosis factor alpha and interleukin 10 than those with localised disease (P < 0.015 and P < 0.05 respectively).  The serum levels of granulocyte macrophage colony stimulating factor and interferon gamma were no different between these groups.  These results suggest immunological effects of NSCLC which tends towards impaired cell mediated immunity in patients with metastatic disease.