title: Influence of peri-operative immunotherapy on serum cytokines and soluble cytokine receptors in patients undergoing surgery for colorectal cancer.
abstract: OBJECTIVE
  The cellular immune response is suppressed following surgery for colorectal cancer. As cytokines influence the patient's immunological responsiveness, we have measured serum cytokines and their soluble receptors in patients receiving peri-operative immunotherapy for colorectal cancer.
  
  
  METHODS
  Fifty-two patients were randomized to receive low dose recombinant IL-2 (rIL-2) alone; rIL-2 with interferon-alpha (IFN-α) or no immunotherapy. Serum cytokines and cytokine receptor levels were measured preoperatively and on post-operative days 1, 4, 7 and 10 using ELISA kits.
  
  
  RESULTS
  Circulating levels of IFN-γ were undetectable in the majority of patients, although IFN-γR levels were increased in all three groups on the first post-operative day (P < 0.05). Similarly, IL-2 was undetectable in most subjects and not enhanced by treatment. However, IL-2R was significantly induced in all patients (P < 0.001), and these levels were higher in both treatment groups when compared with control (P < 0.005). Tumour necrosis factor-alpha (TNF-α) was universally undetectable, but the TNF-R p55 and p75 subunits were induced in all patients (P < 0.005); and as with IL-2R, this was greater in the treatment groups (P < 0.01). Finally, IL-6 production was induced in all groups (P < 0.005), but this was only noted on day 1.
  
  
  CONCLUSIONS
  Soluble cytokine receptors are induced by surgery, and levels of IL-2R and TNF-R are enhanced by exogenous rIL-2 and rIL-2 with IFN-α. This augmentation suggests increased immunocompetence associated with low dose peri-operative immunotherapy.
authors.affiliation: Department of Clinical Medicine, St James's University Hospital, Leeds, UK F. Hoffman-La Roche, Basle, Switzerland.
authors.lastname: Nichols
authors.lastname: Ward
authors.lastname: Gallati
authors.lastname: Primrose