THE EFFECT OF LAPAROSCOPY ON THE MOVEMENT OF TUMOR-CELLS AND METASTASIS TO SURGICAL WOUNDS

Background: A variety of mechanisms have been proposed to explain tumo r growth in port sites following laparoscopic cancer surgery. We devis ed two experimental models to determine whether carbon dioxide (CO2) i nsufflation during laparoscopic surgery influences the movement of tum or cells and leads to tumor implantation and growth in surgical wounds . Methods: Model 1: Viable adenocarcinoma cells were introduced into t he upper abdomen of six syngeneic immune-competent rats during laparos copy with CO2 insufflation; the same procedure was followed for a furt her six rats during gasless laparoscopy. A length of plastic tubing in troduced through the anterolateral aspect of the rats' left lower abdo minal wall was used to vent the insufflation gas through the abdomen o f a recipient rat for 30 min. After 21 days, the peritoneal cavity and surgical wounds of the recipient rat were examined for implanted tumo r. Model 2: A suspension of radiolabeled adenocarcinoma cells was intr oduced into the upper abdomen of five rats during laparoscopy with CO2 insufflation and an additional five rats during gasless laparoscopy. A length of plastic tubing introduced through the anterolateral aspect of the left lower abdominal flank was used to vent the insufflation g as through phosphate-buffered saline solution. After 30 min, the solut ion was counted for radioactivity. Results: Tumor growth occurred at t he site of both the insufflation and venting ports in the second rat i n five of the six rats from the group undergoing insufflation, but it was found in none of the gasless laparoscopy group (p = 0.015). In the second model, significant transfer of tumor cells to the vented gas o ccurred only in the rats undergoing laparoscopy with insufflation (med ian, 2.71% versus 0% of the introduced labeled cells; p = 0.008). Conc lusions: Carbon dioxide insufflation results in tumor dissemination du ring laparoscopy, leading to port site metastasis. Gasless laparoscopy may prevent this problem.