RESUMEN
Radiation therapy in combination with other treatments, such as surgery and chemotherapy, increases locoregional control and survival in patients with thoracic, abdominal and pelvic malignancies. Nevertheless, significant clinical toxicity with combined treatments may be seen in these patients. With the advent of tridimensional conformal radiotherapy (3D-CRT), dose-volume histograms (DVH) can be generated to assess the dose received by the organs at risk. The possible relationship between these parameters and clinical, anatomical and, more recently, genetic factors has to be considered. Treatment options include initial conservative medical therapies, endoscopic procedures, hyperbaric oxygen and surgery. Some pharmacological agents to prevent gastrointestinal toxicity are under investigation.