Table 1.

Modified radiation therapy oncology group rectal toxicity scale

	Clinical summary	Symptom and intervention
Grade 0	No impact	No discernable symptoms or intervention
Grade 1	Mild and self-limiting	Minimal, infrequent bleeding or clear mucus discharge, rectal discomfort not requiring analgesics, loose stools not requiring medications
Grade 2	Managed conservatively, lifestyle (performance status) not affected	Intermittent rectal bleeding not requiring regular use of pads, erythema of rectal lining on proctoscopy, diarrhea requiring medications
Grade 3	Severe, alters patient lifestyle	Rectal bleeding requiring regular use of pads and minor surgical intervention, rectal pain requiring narcotics, rectal ulceration
Grade 4	Life threatening and disabling	Bowel obstruction, fistula formation, bleeding requiring hospitalization, surgical intervention required
Grade 5	Death	Death directly related to radiation effects