Dispersal of tumour cells within the peritoneal cavity during laparoscopy

Summary

Disagreement exists about whether laparoscopy results in dispersal of tumour cells during laparoscopic cancer surgery and whether this results in the development of port-site metastases. Recent experimental work suggests that CO₂, but not He, insufflation promotes the development of port-site metastases, suggesting that metabolic or immunological factors might also contribute to this problem. This study investigated whether insufflation results in an initial redistribution of tumour cells; and looked at the contribution of mechanical insufflation factors for the development of port-site metastases. A suspension of radio-labelled cancer cells was introduced into the left upper quadrant of the peritoneal cavity of 17 Dark Agouti rats, which underwent laparoscopy with CO₂ pneumoperitoneum, gasless laparoscopy, or laparotomy. Surgery continued for a further 30 min, after which the rats were killed and the radioactivity present on the peritoneal surface of the anterior and lateral abdominal wall, and the laparoscopy port sites, was determined by scanning standardised samples of the abdominal wall with a y counter. There was less contamination of the abdominal wall from laparotomy than laparoscopy, irrespective of technique. No differences in contamination between the two laparoscopy groups could be demonstrated. Contamination of the port sites was similar except at the site through which the cells were originally introduced, where a greater radioactivity concentration was seen following gasless laparoscopy. This study suggests that it is not the use of gas insufflation during laparoscopy which is responsible for redistribution of tumour cells from a tumour site, but that redistribution is related to some other aspect of the laparoscopic environment. It is possible, when this finding is considered alongside previously reported studies, that a metabolic or immune disturbance, due to other properties of CO₂ insufflation, could cause this problem. This possibility is being investigated further.

Keywords:

• laparoscopy
• tumour
• metastasis
• port sites
• radioactivity