Viable intraluminal tumour cells and local/regional tumour growth in experimental colon cancer.

To determine if viable intraluminal tumour cells can leak through a watertight anastomosis and cause local/regional (extraluminal) tumour growth, tumour cells were introduced 2 cm proximal to a colonic anastomosis following laparotomy in a Wistar/Furth rat colon cancer model. Local/regional tumour growth was observed in all rats except a sham anastomotic group. No intraluminal tumour growth was observed in either group. Viable intraluminal tumour cells cause local/regional tumour growth by leakage through a clinically intact anastomosis and may be an important cause of local/regional tumour growth in human colorectal cancer.