Gastrointestinal radiation injury: Symptoms, risk factors and mechanisms

Abstract

Ionising radiation therapy is a common treatment modality for different types of cancer and its use is expected to increase with advances in screening and early detection of cancer. Radiation injury to the gastrointestinal tract is important factor working against better utility of this important therapeutic modality. Cancer survivors can suffer a wide variety of acute and chronic symptoms following radiotherapy, which significantly reduces their quality of life as well as adding an extra burden to the cost of health care. The accurate diagnosis and treatment of intestinal radiation injury often represents a clinical challenge to practicing physicians in both gastroenterology and oncology. Despite the growing recognition of the problem and some advances in understanding the cellular and molecular mechanisms of radiation injury, relatively little is known about the pathophysiology of gastrointestinal radiation injury or any possible susceptibility factors that could aggravate its severity. The aims of this review are to examine the various clinical manifestations of post-radiation gastrointestinal symptoms, to discuss possible patient and treatment factors implicated in normal gastrointestinal tissue radiosensitivity and to outline different mechanisms of intestinal tissue injury.

Pain in cancer survivors

“…98,99 These changes in turn lead to gut dysmotility, stricture formation and obstruction all of which ultimately manifest as chronic abdominal pain. 100 Preventative strategies attempt to ameliorate the degree of gut fibrosis either by interfering with radiation specific mechanisms of injury or by increasing the tolerance of normal tissue to radiation. 101 Refinements in dosimetry and beam targeting, the use of antiinflammatory and antioxidant agents and therapies aimed at increasing tissue vascularity and oxygen supply such as hyperbaric oxygen have been tried.…”

Application of human bone marrow-derived mesenchymal stem cells in the treatment of radiation-induced Gastrointestinal syndrome

“…b-FGF promotes stem cell renewal, progenitor cell differentiation and epithelial cell proliferation. Systemic administration of b-FGF is capable of suppressing ASMase in endothelial cells, which in turn was found to protect the murine small intestine from radiation-induced damage [17,18]. Zhang et al [17] have shown that survival of crypt epithelial cells is significantly increased and apoptosis of endothelial cells pharmacologically inhibited in mice by intravenous injection of b-FGF prior to irradiation.…”

Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

“…The incidence of proctitis is closely associated with the applied radiation therapy technique. Despite use of techniques with lower fraction size, which reduces normal tissues injury, acute proctitis still occurs in a high proportion of patients following pelvic radiation therapy (1). Even though acute radiation proctitis is usually self-limited, it impairs the quality of life of patients.…”