Increased tumor establishment and growth after laparotomy vs laparoscopy.

It has been well known that surgical treatment induces the immunosuppressive effect and that it might promote tumor growth and metastasis. However, the mechanisms of this phenomenon are still unclear. Recently, laparoscopic treatment has been considered to reduce surgical damage. Allendorf et al 1 provided evidence that tumor cells inoculated into the dorsal skin grew more easily and progressively after laparotomy than after peritoneal insufflation with carbon dioxide. We congratulate the authors in demonstrating the hypothesis that laparoscopic procedures may preserve the immune function. Our clinical data also show that laparoscopic cholecystectomy could reduce the immunologic damage induced by surgery. 2 We suspected that exposure of the peritoneal cavity to air induces bacterial translocation from the gut, resulting in the impaired immune function. 3 We studied this point using rat models. After being anesthetized with ether, inbred LEW (MHC haplotype RT1 1 ) rats underwent either 70% liver resection, ileal anastomosis, laparotomy