Gastrointestinal radiation injury: Symptoms, risk factors and mechanisms

Table 1 Example of some gastrointestinal symptoms grades following radiation injury

Grade	Gastrointestinal symptoms
	Nausea
1	Loss of appetite without alteration in eating habits
2	Oral intake decreased without significant weight loss, dehydration or malnutrition; IV fluids indicated < 24 h
3	Inadequate oral caloric or fluid intake; IV fluids, tube feedings, or TPN indicated ≥ 24 h
4	Life-threatening consequences
5	Death
	Anorexia
1	Loss of appetite without alteration in eating habits
2	Oral intake altered without significant weight loss or malnutrition; oral nutritional supplements indicated
3	Associated with significant weight loss or malnutrition (e.g., inadequate oral caloric and/or fluid intake); IV fluids, tube feedings or TPN indicated
4	Life-threatening consequences
5	Death
	Haemorrhage-GI
1	Mild, intervention (other than iron supplements) not indicated
2	Symptomatic and medical intervention or minor cauterization indicated
3	Transfusion, interventional radiology, endoscopic, or operative intervention indicated; radiation therapy (i.e., hemostasis of bleeding site)
4	Life-threatening consequences; major urgent intervention indicated
5	Death
	Ulceration-GI
1	Asymptomatic, radiographic or endoscopic findings only
2	Symptomatic; altered GI function (e.g., altered dietary habits, oral supplements); IV fluids indicated < 24 h
3	Symptomatic and severely altered GI function (e.g., inadequate oral caloric or fluid intake); IV fluids, tube feedings, or TPN indicated ≥ 24 h
4	Life-threatening consequences
5	Death
	Incontinence anal
1	Occasional use of pads required
2	Daily use of pads required
3	Interfering with ADL; operative intervention indicated
4	Permanent bowel diversion indicated
5	Death

According to the Common Terminology Criteria for Adverse Events system v 3.0. IV: Intravenous; GI: Gastrointestinal; ADL: Activities of daily living; TPN: Total parenteral nutrition.