A model of port-site metastases of gallbladder cancer: The influence of peritoneal injury and its repair on abdominal wall metastases

Background. Recent surgical literature contains several reports of wound me tastases of unexpected gallbladder cancer after laparoscopic cholecystectom y. We hypothesized that peritoneal injury caused by trocar insertion potent iates wound metastases. This study was designed to determine the effect of peritoneal injury on tumor implantation. Methods. Cultured human gallbladder cancer cells were injected into the per itoneal cavity of mice immediately after surgical procedures. In a peritone al injury group muscle and the peritoneum were perforated; in a peritoneal injury and repair group each muscle and peritoneal wound was sutured carefu lly; in a laparoscopic model group animals underwent peritoneal insufflatio n with carbon dioxide gas and tumor cell injection and then the abdominal w all was perforated. Some mice (controls) were not subjected to any surgical procedure. All mice (n = 178) were killed 2 weeks after tumor cell injecti on and were examined for tumor implantation. Results. Although no control mice showed intraperitoneal tumor, all mice in the peritoneal injury group showed tumors at the injured sites. In the lap aroscopic model group, 90% of injured sites had tumors. The traumatized sit e-specific implantation rate in the peritoneal injury and repair group was only 40%, whereas it was 100% in the peritoneal injury group (P < .001). Conclusions. Peritoneal injury enhances peritoneal implantation of carcinom a cells. Repair of injured peritoneum at trocar sites may reduce the freque ncy of wound metastases in laparoscopic surgery for unexpected gallbladder carcinoma.