Basics of vascular damage and progress of diagnosis and treatment in radiation intestinal injury

Abstract

Radiation intestinal injury is one of the most common complications after abdominal pelvic radiotherapy, which seriously affects the quality of life for patients. According to the site of occurrence, it is divided into radiation enteritis, colitis and proctitis. The pathological characteristics of radiation intestinal injury mainly include interstitial fibrosis, mucosal edema, ulcers, and inflammatory cell infiltration, and significant vascular lesions as well. It showed telangiectasia and hemorrhage under endoscopy. Under ultrasound examination, it showed diffusive thickening of the intestinal wall and increased blood flow signals. In addition, it also has other features such as increased thickness of the distal sigmoid colon and rectal wall, and increased width of the presacral space. The key factors in the incidence and development of radiation intestinal injury include angiostatin, PDGF, CXCL16, etc. The mechanisms to be clarified include abnormally heightened angiostatin through which signal pathways specifically affect vascular endothelial cells and inhibit angiogenesis and vascular homeostasis, how CXCL16 expressed by macrophages interacting with receptor promotes the transformation of fibroblasts and vascular smooth muscle cells into myofibroblasts, etc. Therapy targeted on basics of vascular damage will be a promising field of radiation intestinal injury research.