Early proctoscopy is a surrogate endpoint of late rectal toxicity in prostate cancer treated with radiotherapy.

Purpose: To predict the grade and incidence of late clinical rectal toxicity through short-term (1 year) mucosal alterations.

Methods And Materials: Patients with prostate adenocarcinoma treated with curative or adjuvant radiotherapy underwent proctoscopy a year after the course of radiotherapy. Mucosal changes were classified by the Vienna Rectoscopy Score (VRS).