In case of massive tissue damage, the ensuing inflammatory reaction produces a potentially lethal cocktail of active mediators. Beside the influence of these local factors on local tumour recurrence, we hypothesize that during surgery systemically produced mediators are potential stimulators of tumour cell adhesion as well. The aim of this study was to investigate the influence of serum samples, obtained at eight different time periods before, during, and after surgery on the interaction between human colon carcinoma cells and mesothelial cells. In the control situation, the average adhesion of the Caco-2 cells to the mesothelial monolayers was 29%. No enhancement in adhesion was observed after incubation of the mesothelial cells with the pre- or postoperative serum of the patients. This study suggests that systemic factors produced directly after surgery are not influencing tumour adhesion to mesothelial monolayers. Therefore, local tumour recurrence is probably only influenced by locally produced factors.