Intraperitoneal tumor growth is influenced by pressure of carbon dioxide pneumoperitoneum

Background: Several studies have indicated that the carbon dioxide (CO2) pneumoperitoneum during laparoscopy plays a role in the pathogenesis of port-site metastases. An experimental animal study was performed to investigate the impact of various pneumoperitoneum pressures on peritoneal tumor growth. Methods: In this study, 36 male WAG rats were randomized into three groups; two groups with different pneumoperitoneum pressures (16 mmHg and 4 mmHg) and one group of gasless controls. After a pneumoperitoneum of 0.5 x 10(6) mi was established, 531 tumor cells were injected intraabdominally and the pneumoperitoneum was maintained for 60 min. Peritoneal tumor growth was assessed on day 11 at autopsy. Results: Peritoneal tumor growth in the 16-mmHg group was significantly greater than in the 4-mmHg group (p = 0.039) and the gasless group (p = 0.004). Conclusions: High-pressure CO2 pneumoperitoneum stimulates intra-abdominal tumor growth. The use of low insufflation pressures in laparoscopic cancer surgery should be considered.