Intraperitoneal heparin decreases tumour implantation following laparoscopy

Background: Conclusions drawn from clinical reports of port site metastases following laparoscopic resection of intra-abdominal malignancies are supported by a burgeoning experimental literature which demonstrates that laparoscopy promotes tumour metastasis to wounds. We investigated the effect of intraperitoneal blood and heparin on the incidence of tumour cell implantation and port site metastases. Methods: Twenty four Dark Agouti rats underwent laparoscopy with CO2 insufflation and the instillation of a tumour cell suspension and/or blood into the peritoneal cavity. Rats were randomly allocated to one of the following study groups: Group 1: control Group 2: intraperitoneal blood (introduced from a syngeneic donor rat) Group 3: intraperitoneal heparin Group 4: intraperitoneal blood + heparin. Rats were killed 7 days after the procedure, and the peritoneal cavity and port sites were examined for the presence of tumour. Results: Tumour implantation and port site metastases were significantly reduced by the intraperitoneal administration of heparin, but increased by the presence of blood. Conclusion: The results of this study suggest that tumour implantation following laparoscopy is promoted by the presence of intraperitoneal blood and that this effect might be reduced by the use of intraperitoneal heparin