The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients.

The records of 88 patients with radiation-induced proctosigmoidosis seen over an eight year period were reviewed. Eighty-four (95 per cent) had been irradiated for a gynaecological malignancy. The peak incidence of bleeding occurred after a latent period of nine months from the time of irradiation. Twenty-five subjects (28 per cent) had associated injury to the urinary tract. A wide spectrum of radiological abnormalities found on barium enema is described. Twenty-four patients (27 per cent) underwent operations for radiation-induced injury to the colon and urinary tract. Operations on the bowel were attended by a high complication rate (79%). A clinical classification based on bowel symptoms is presented. Those whose only symptom was low grade rectal bleeding (Group I) had the most favourable outcome and of these, 35 per cent stopped bleeding spontaneously by six months. Patients who required frequent transfusions (Group II) had an increasing mortality rate with the passage of time. Patients whose predominant symptoms were pain and bowel dysfunction (Group III) had the highest death rate but some did well after an operative procedure.