A small mammal model of tumour implantation, dissemination and growth factor expression after partial hepatectomy

BackgroundSurgical resection remains the most effective therapy for metastatic colorectal cancer confined to the liver, although the extrahepatic recurrence rate is high.Aim of the studyTo develop a mammal model in order to investigate by which mechanisms liver surgery affects distant tumour recurrence.MethodsIn this animal study the effect of partial hepatectomy (phX) on the development of tumour noduli in the lungs was evaluated. CC531 rat colon carcinoma cells were inoculated i.v. 24 h before, during or 24 h after surgery. Rat serum was obtained at different time-points after phX and added to in vitro CC531 cell cultures. Finally, phX was compared with an ileum resection (ilX).ResultsphX leads to increased tumour noduli in the lungs, compared to Sham operation (p = 0.002), but only when performed directly before the injection of tumour cells and not when performed 24 h before or after the inoculation. Comparable results were obtained for ilX. No growth stimulation of tumour cells after incubation with rat serum, obtained at different time-points after phX, could be detected in vitro.ConclusionNot only phX, but also surgery, in general promotes distant tumour recurrence exerting the effect during the early phase of tumour cell adhesion and not during tumour outgrowth.