Clinical Utility of Combined 18F-Fluoro-2-deoxyglucose Positron Emission Tomography – Computed Tomography in the Evaluation of Gastrointestinal Malignancies

18F-Fluoro-2-deoxyglucose positron emission tomography (FDG PET) has demonstrated high accuracy in the staging and evaluation of colorectal and esophageal carcinomas. Current data supports the emerging use for staging and evaluation of recurrence in a number of other gastrointestinal tumors including pancreatic, hepatocellular, and gastric carcinomas, as well as gastrointestinal stromal tumors, cholangiocarcinoma, and carcinoma of unknown primary. The current established and emerging clinical indications, the diagnostic accuracy, and the limitations for GI tumors will be reviewed. The use of combined PET-CT further improves diagnostic accuracy. Keywords: Positron emission tomography, fluorodeoxyglucose, computed tomography, colorectal cancer, gastrointestinal neoplasms, esophageal cancer, review