In vivo real-time analysis of intraperitoneal radiolabeled tumor cell movement during laparoscopy

PURPOSE: A porcine model has been developed to allow the real-time imaging of radiolabeled tumor cell movement throughout the peritoneal cavity, both at rest and during carbon dioxide insufflation. METHODS: Fifteen 30-kg dome stic white female pigs were used. Under anesthesia, 15 to 20 million radiol abeled human colorectal tumor cells (LIM1215) were introduced into the peri toneal cavity under laparoscopic vision into the pelvis. Radiolabeled tumor cell movement was examined by using a 25-cm-diameter, low-energy mobile ga mma camera with high resolution collimator. Tumor cell movement and distrib ution during two hours without insufflation was examined in four pigs. Then tumor cell movement and distribution during two hours with CO2 insufflatio n was examined in four pigs. In a further four pigs, tumor cells were then mixed with blood and injected into the peritoneal cavity and the effect of no insufflation vs. insufflation was noted. A further three pigs were exami ned with manipulation of the intra-abdominal contents after injection of LI M1215 cells into the peritoneal cavity. Venting insufflating CO2 was filter ed for tumor cells. RESULTS: Widespread intraperitoneal distribution of tum or cells from the pelvis was identified both with CO2 insufflation of the p eritoneal cavity and without insufflation. Tumor cells dispersed throughout the peritoneal cavity at a slower rate without carbon dioxide insufflation . There was a differential rate of tumor cell movement to the left upper qu adrant and right upper quadrant with insufflation and without insufflation. Blood within the peritoneal cavity and an extended contact of the laparosc opic trocars with the peritoneal cavity in this setting increased contamina tion of the trocars and trocar sites with tumor cells. Tumor cells were ide ntified on laparoscopic instruments in all experiments. No evidence of aero solization of tumor cells was found. CONCLUSION: Tumor cells move throughou t the peritoneal cavity both at rest and during CO2 insufflation. The patte rn of tumor cell dispersion differs with CO2 insufflation. The presence of blood and extended contact of trocars with peritoneal contents are a major factor in trocar and trocar site tumor cell contamination.