Topical treatments of laparoscopic port sites can decrease the incidence of incision metastasis

Background: Antecdotal reports of port site tumor recurrence have dampened the enthusiasm for laparoscopic colectomy for cancer. We developed a rat model that creates a high incidence of port site metastasis following laparoscopic intervention. Our goal was to assess the feasibility of minimizing implantations using port site irrigation prior to wound closure. Methods: Colon cancer carcinomatosis was established in 46 female BD9 rats using intraperitoneal injections of 10⁶ DHD-K12-TRb rat colon cancer cells. This preparation yielded an 81% incidence of port site metastasis in a control group. Laparoscopic sham surgery was performed using four ports and a CO₂ pneumoperitoneum. Four treatment groups were studied by irrigating each port site as follows: Group I, sterile water; group II, normal saline; group III, heparin; group IV, 5-flurouracil (5-FU). The animals were killed at 4 weeks, and the port sites were examined for tumors. Results: There were no differences in port site metastasis between controls and groups I, II, and III. The 5-FU group showed a significant decrease (30% vs 81%) in metastasis. Conclusions: Port site irrigation with 5-FU at the time of laparoscopy reduces the incidence of port site tumor implantation in a rat colon cancer model. This finding may have utility in patients at high risk of such metastasis who undergo laparoscopy for colon cancer.