Tumor implantation following laparoscopy using different insufflation gases.

BACKGROUND: Laparoscopic manipulation of malignancies is associated with an increased incidence of metastasis to port sites in experimental models. This study investigated the effect of different insufflation gases on the implantation of a tumor cell suspension following laparoscopic surgery in an established small animal model. METHODS: Forty Dark Agouti rats underwent laparoscopy and the introduction into the peritoneal cavity of a tumor cell suspension. The insufflating gas used for each procedure was one of the following gases (10 rats in each group): carbon dioxide (CO2), nitrous oxide (N2O), helium, and air. The rats were killed 7 days after surgery, and the peritoneal cavity and port sites were examined for the presence of tumor. RESULTS: Although no significant differences were seen between air, CO2, and N2O insufflation groups, tumor involvement of peritoneal surfaces was less likely following helium insufflation. CONCLUSION: The results of this study suggest that tumor metastasis to port sites following laparoscopic surgery may be influenced by the choice of insufflation gas. In this study, helium was associated with reduced tumor growth.