Purpose: To evaluate the prevalence of disordered gastrointestinal function following therapeutic irradiation.
Methods and materials: Gastrointestinal function was evaluated in 30 randomly selected patients who had received pelvic irradiation for treatment of carcinoma of the cervix between 1 and 6 years previously. Each patient underwent evaluations of (a) gastrointestinal symptoms (b) absorption of bile acid, vitamin B12, lactose and fat (c) gastrointestinal transit: gastric emptying, small intestinal transit and whole gut transit and (d) intestinal permeability. Results were compared with those obtained in 18 normal volunteers.
Results: Stool frequency was above the control range in five patients and had increased (p < 0.001) since radiotherapy treatment. Bile acid (p < 0.001) vitamin B12 (p < 0.01) and lactose (p < 0.01) absorption were less in the patients when compared with the control subjects. Bile acid absorption was below the control range in 14 of the 30 patients. Dietary calcium intake was lower (p < 0.05) in those patients with lactose malabsorption. Gastric emptying (p < 0.01) and small intestinal transit (p < 0.01) were more rapid in the patients. Both small intestinal (r = -0.39, p < 0.05) and whole gut (r = -0.45) transit were inversely related to stool frequency. Either bowel frequency, bile acid absorption, vitamin B12 absorption was outside the control range in 19 of the 30 patients.
Conclusion: Abnormal gastrointestinal function is essentially an inevitable long-term sequel of pelvic irradiation.