Radiation Therapy Did Not Induce Long-Term Changes in Rectal Mucosa: Results From the Randomized Scandinavian Prostate Cancer Group 7 Trial

Radiation therapy to 70 Gy to the prostate does not induce long-term microscopic mucosal changes in the rectum 5 years after treatment. This is in contrast to the general assumption that structural changes, including fibrosis, seen after radiation therapy include the mucosa. We speculate that the main late effects of radiation therapy on the structure of the rectum are located in the deeper layers of the rectal wall than the mucosa.