Argon plasma coagulation in chronic radiation proctitis.

Chronic radiation proctitis is a relatively common late complication of pelvic irradiation. The main symptoms are diarrhea, urgency, tenesmus, and rectal bleeding. While mild cases may settle spontaneously over some months, severe hemorrhagic radiation proctitis may require repeated blood transfusions and is difficult to treat with medical therapy. Argon plasma coagulation (APC) is a noncontact thermal coagulation technique which can be applied endoscopically. A probe passed through the scope delivers a field of argon gas to the mucosal surface where it is ionized by a high voltage filament, resulting in superficial mucosal heating and coagulation of friable blood vessels. The technique reduces rectal bleeding in 80%-90% of cases, and may improve the other troublesome symptoms of diarrhea and urgency. APC is probably less effective in very severe cases of hemorrhagic radiation proctitis; in these cases topical formalin or a combination of APC and topical formalin can be useful. Overall, APC has proved to be a safe and well tolerated technique.