A 49-year-old computer technician receives irradiation to the pelvis for cervical cancer. Three months after irradiation, severe rectal proctitis may be shown by the presence of which of the following?

The mucosa is friable and bleeds readily. Ulcers vary in size and often tend to be transverse in position and surrounded by telangiectasis. They are often more prominent on the anterior wall around the anal verge. Rectal strictures usually are located about 8-12 cm above the anal verge. Rectovaginal fistula may develop in female patients. On barium enema, a narrow stricture is difficult to differentiate from a carcinoma.