Laparoscopic surgery in the rat - Beneficial effect on body weight and tumor take

Background: The ability of laparoscopic techniques to treat malignant disease is controversial. We developed a rat model to assess metabolic and oncological effects of laparoscopic surgery. Methods: Experiment I. The postoperative body weight in 10 rats having laparoscopic bowel resection (group I). 10 rats having open bowel resection (group II) and 5 rats having anesthesia only (group III) was determined. Experiment II. Tumor rake was scored in ii rats having laparoscopic bowel resection (group IV), 11 rats having open bowel resection (group V), 6 rats having CO2 pneumoperitoneum without bowel resection (group VII and 6 rats having anesthesia only (group VII). All rats had CC531 cancer cells injected intraperitonrally postoperatively. Results. Experiment I. Body weight loss in group I com- pared to group II (p < 0.036). Rats of group III lost no weight postoperatively. Experiment II. Tumor take was less in the subcutis (p = 0.005), parietal peritoenum (p < 0.001) and bowel anastomosis (p = 0.021) in group IV compared to group V. Tumor take was significantly greater at all sites except for subcutis in group VI compared to VII (all p < 0.022). Conclusions: Laparoscopic surgery is associated with less postoperative weight loss and less turner take compared to open surgery. CO2 insufflation appeals to increase tumor take.