Liver metastasis following pneumoperitoneum with different gases in a mouse model

Background: The validity of using CO, in laparoscopic tumor surgery has not yet been established. To address this question, we investigated the growth of liver metastases following insufflation with different gases in a mouse laparoscopy model. Methods: Male BALB/C mice inoculated intraportally with colon 26 cells were randomized to undergo pneumoperitoneum with CO2 (n = 16), helium (n = 16), argon (n = 16), or air(n = 17), or to act as controls without insufflation (n = 17). Results: The growth of cancer nodules on the liver 14 days after surgery wa s greater in mice following insufflation with CO2 (p < 0.01), helium (p < 0 .01), argon (p = 0.01), and air (p = 0.07) than in control mice. No signifi cant differences were found between the four insufflation groups in the gro wth of liver metastases. Conclusion: These results suggest that insufflation plays an important role in the development of liver metastases but that the choice of gas may not affect their growth.