title: Peritoneal irrigation with povidone-iodine solution after laparoscopic-assisted splenectomy significantly decreases port-tumor recurrence in a murine model.
abstract: OBJECTIVE
  The development of port-wound tumor recurrences has raised questions regarding the safety of laparoscopic methods for the resection of malignancies. The cause and the incidence of abdominal-wall tumor recurrences remain unknown. It is also not clear how to avoid or lower the incidence of port-tumor recurrences. The purpose of the current study was to determine the impact of abdominal irrigation with povidone-iodine on the port-wound tumor incidence in a murine model.
  
  
  METHODS
  A splenic tumor model was used for this study. To establish splenic tumors, female BALB/c mice (N = 48) were given subcapsular splenic injections of a 0.1 ml suspension containing 10(5) C-26 colon adenocarcinoma cells via a left-flank incision at the initial procedure. Seven days later, the animals with isolated splenic tumors (100 percent) were randomly assigned to one of three groups: 1) control, 2) saline irrigation (saline), or 3) povidone-iodine irrigation. All animals underwent laparoscopic mobilization of the spleen using a three-port technique, intra-abdominal crushing of the tumor, followed by an extracorporeal splenectomy via a subcostal incision. No irrigation was performed for control group animals. In the saline irrigation group, the subcostal incision was closed and pneumoperitoneum was re-established. The abdominal cavity was irrigated with 5 ml of normal saline for 60 seconds before instrument removal. In the povidone-iodine irrigation group, similar abdominal irrigation was performed, using 0.25 percent povidone-iodine. Attempts were made to recover completely the irrigation for both irrigation groups. Seven days after the splenectomy, animals were killed and inspected for abdominal-wall tumor implants.
  
  
  RESULTS
  There were significantly more animals with at least one port-tumor recurrence in the control group than in the povidone-iodine group (P = 0.007). Although not statistically significant, the number of animals with port-wound tumors was higher in the saline group than in the povidone-iodine group (P < 0.08). There was no significant difference between the saline group and the control group. When each port site was considered independently, the incidence of port-wound tumors (number of ports with tumors per total number of ports) was significantly lower in the povidone-iodine group than in both the control (P = 0.00001) and saline groups (P = 0.03). The incidence of port-wound tumors was also significantly lower in the saline group compared with the control group incidence (P = 0.03).
  
  
  CONCLUSIONS
  Abdominal irrigation with dilute povidone-iodine solution significantly reduced the number of animals with port-tumor recurrences. Abdominal irrigation with saline was also effective in reducing the incidence of port-wound tumor formation when each port was considered separately. However, povidone-iodine irrigation was much more effective than saline irrigation in preventing port-wound tumor formation.
authors.affiliation: Department of Surgery, Columbia-Presbyterian Medical Center, New York, New York, USA.
authors.forename: S W
authors.initials: SW
authors.lastname: Lee
authors.forename: N R
authors.initials: NR
authors.lastname: Gleason
authors.forename: M
authors.initials: M
authors.lastname: Bessler
authors.forename: R L
authors.initials: RL
authors.lastname: Whelan
mesh_terms: D000230:Adenocarcinoma / Q000601:surgery; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D005069:Evaluation Studies as Topic; D005260:Female; D010535:Laparoscopy / Q000009:adverse effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D009366:Neoplasm Seeding; D010865:Pilot Projects; D011206:Povidone-Iodine / Q000627:therapeutic use*; D011897:Random Allocation; D013156:Splenectomy / Q000379:methods*; D013160:Splenic Neoplasms / Q000601:surgery; D007507:Therapeutic Irrigation; D014407:Tumor Cells, Cultured
chemical_list: D000891:Anti-Infective Agents, Local; D011206:Povidone-Iodine