Impact of laparoscopic surgery on experimental hepatic metastases

Background: Metastatic disease to the liver is one of the major factors determining outcome after colonic resection with curative intention. The influence of laparoscopic surgery on metastatic disease in the liver is still largely unknown. Methods: An intrasplenic tumour cell inoculation was performed in 30 WAG-Rij rats. After 7 days the rats were randomized into three operative groups: laparotomy (n = 10), laparoscopy with 7 mmHg carbon dioxide pneumoperitoneum (n = 10) and gasless laparoscopy (n = 10). A small bowel segmental resection was carried out in all rats. Some 21 days later the rats were evaluated for number and diameter of tumour nodules and cancer index score at eight different abdominal sites. Results: Hepatic tumour growth scored with the cancer index was significantly reduced in the gasless laparoscopy group compared with that in the carbon dioxide laparoscopy group (P = 0·04) and the laparotomy group (P = 0·02). Tumour growth at the port site and total tumour load were significantly reduced in the gasless group compared with the laparotomy group (P ≤ 0·04). Conclusion: Laparoscopy with carbon dioxide insufflation seems to stimulate the growth of dormant tumour cells into overt liver metastases. Gasless laparoscopy on the other hand may have a protective effect against metastatic disease in the liver. The promoting and inhibiting effects of laparoscopic procedures on growth of liver metastases need further evaluation. © 2001 British Journal of Surgery Society Ltd