Introduction: Upper GIT carcinomas are the most common malignancies in both sexes. In 2018, stomach cancer was the most commonly diagnosed upper GIT cancer then closely followed by liver cancer, esophageal cancer, pancreatic cancer and gallbladder cancer in terms of incidence and mortality. Radiation therapy is among the main modality of cure, control and palliation of upper GIT malignancies. However, the advantage of radiation therapy combined with other modalities in upper GIT cancers has been established, challenges remain in providing accurate and safe radiation delivery. These challenges include proximity of organs at risk within the abdomen, nature of organs motion and gastrointestinal filling.
Purpose: The aim of this study is to evaluate the dosimetric effect of gastric filling on the motion of targets and organs at risk in patients with upper gastrointestinal and pancreatic cancers receiving radiotherapy.
Material and methods: A prospective study included 30 patients with upper GIT malignancies. All patients were treated with radiation therapy and were instructed to take nothing by mouth at least 8 hours before the simulation of the treatment. CT simulator (SIEMENS, somatom go. Up) two sets of images were taken, the first image was taken after on fasting state, then the second scan was taken after the patient drank 1.5L of water within 30 minutes.