Tumour cell wound distribution after colectomy in a porcine model

Background: Concerns over tumour implants have impeded the adoption of laparoscopic surgery for cancer. Explanations assume an increased number of malignant cells present in trocar wound sites. The following are tested in the present paper: (i) that the magnitude of wound contamination following surgery is related to the location of the tumour cells; and (ii) the surgical approach. Methods: We have used a porcine sigmoid colectomy model to compare the number of tumour cells on laparoscopic wounds after resections in the presence of intraluminal, intramural and intraperitoneal Cr-51-labelled, fu;ed HeLa tracer cells. Open colectomies were also performed in the presence of intraperitioneal tracer cells and their numbers on laparotomy wound surfaces were determined by gamma counting. Results: With intraperitoneal cells, laparotomies had 1087 (+/-106) tracer cells per mm (n=4) while trocar wounds had 103 (+/-54) cells per mm (n=10) (P>0.05). Resection of intramural tumours resulted in lower trocar wound contamination (0.9+/-0.6 cells/mm, n=3). Resection of colon including intraluminal tracer cells resulted in 2.9 +/- 2.1 cells/mm on trocar wounds (n=3). Conclusions: More tumour cells were deposited on open than laparoscopic trocar wound surfaces. Also, the risk of wound implantation is less with intraluminal or intramural tumours than with intraperitoneal cells (P>0.05).