Impact of laparoscopic colonic resection on tumour growth and spread in anexperimental model

Background: The influence of surgical manipulation and carbon dioxide pneum operitoneum on intraperitoneal tumour growth and port-site metastasis durin g laparoscopic colon resection is still unknown. Methods: Some 33 male WAG/Rij rats were randomized into three experimental groups: a laparoscopy group with carbon dioxide pneumoperitoneum (n = 11), a gasless laparoscopy group (n = 11) and a laparotomy group (n = 11). After transanal injection of a tumour cell suspension (1 x 10(6) CC 531 cells) i nto the distal colon, a colon segment resection and an end-to-end anastomos is (laparoscopy; intraabdominal technique) were performed. Tumour growth wa s scored semiquantitatively 24 days after the operation. Data were analysed by the Kruskal-Wallis test. Results: The tumour indices from the four locations with the greatest tumou r growth were significantly decreased in the laparoscopy group with carbon dioxide pneumoperitoneum compared with the gasless laparoscopy and laparoto my groups (P < 0.01). Port-site metastases were significantly decreased in the carbon dioxide pneumoperitoneum group compared with the gasless laparos copy group (P = 0.05). Conclusion: A full laparotomy incision promotes greater tumour growth than does carbon dioxide pneumoperitoneum. Surgical manipulation stimulates loca l tumour spread more than the establishment of a carbon dioxide pneumoperit oneum.