The efficacy of agents employed to prevent anastomotic recurrence in colorectal carcinoma.

Forty-eight of 72 surgeons canvassed in the South West of England (67%) routinely use an intraluminal cytotoxic agent to prevent suture-line recurrence following partial resection of the large bowel for cancer. The most popular agents are chlorhexidine-cetrimide preparations (n = 14), mercuric perchloride (12), povidone-iodine (7) and water (12); noxythiolin, sodium hypochlorite and silver nitrate are used occasionally. The mean duration of treatment is 2 minutes. When assayed for cytotoxity against tumour cells freshly prepared from human colorectal carcinomas (n = 10), both chlorhexidine-cetrimide and povidone-iodine were rapidly lethal at a wide range of concentrations (5-100%). Mercuric perchloride (0.2%) was similarly effective, but up to 20% of tumour cells remained viable after exposure to noxythiolin and nearly 30% with water alone. Chlorhexidine-cetrimide and povidone-iodine are the agents of choice to kill malignant cells exfoliated into the colorectal lumen.