Normal tissue reactions to high dose-rate intracavitary irradiation of the vagina with different fractionation schedules and dose levels.

The radiation reactions in the normal tissues of the vagina, rectum and bladder were studied in 166 patients receiving prophylactic vaginal high dose-rate intracavitary irradiation. Most reactions were observed in the vaginal mucosa included in the intracavitary target and only a few in the rectum and bladder in close proximity to the same target. The influence of the total dose, the dose per fraction and the overall treatment time, summarized as the Cumulative Radiation Effect (CRE), correlated well to the rate of reactions after a correction of the formula for late effects.