[Diagnosis and treatment of radiation intestinal injury: current status and perspectives]

Radiation intestinal injury (RII) refers to the intestinal complication resulting from radiation therapy of pelvic, abdominal or retroperitoneal tumor, which involves the small intestine, colon and rectum. Although the advances in radiotherapy technology have decreased the injury of adjacent tissues, 90% of the patients receiving radiotherapy have acute symptoms, the quality of life is affected due to gastrointestinal symptoms in 50% of patients, and 20%-40% of patients have moderate to severe symptoms. Based on the pathological stage, characteristics and clinical manifestations, RII can be divided into acute and chronic types, generally 3 to 6 months as the cutoff in clinical history. The main preventions of RII include reducing the radiation doses and narrowing the exposure fields. Acute RII is characterized by mucosal inflammation and self-limitation, and its treatment includes symptomatic and nutritional management. As the chronic ischemia and fibrosis in chronic RII are irreversible, bowel resection is the ideal treatment. The surgical indications for chronic RII are grade 3 and 4 intestinal injuries, including obstruction, bleeding, intestinal necrosis, perforation, and fistula. The current surgical procedure is definitive intestinal resection with stage I or II gastrointestinal reconstruction. The optimal time for definitive surgery is still controversial. Based on our experiences, 1 year after the end of radiation therapy is optimal. Under the circumstances of emergency surgery, severe malnutrition, abdominal infection, extensive intestinal injury, and abdominal adhesions that cannot be mobilized, ostomy and abdominal drainage are recommended, and definitive surgery can be considered after the return to enteral nutrition and extinction of intestinal inflammation. Preoperative setting of ureteral catheter, imaging assessment of colorectal position and iliac vascular injury, and preoperative nutritional support can reduce the risk of systemic complications effectively.