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 × 10⁶ ml was established, 531 tumor cells were injected intra-abdominally 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. Received: 1 December 1998/Accepted: 10 July 1999/Online publication: 9 August 2000