PET/CT in GI Malignancies

Introduction

Positron Emission Tomography/Computed Tomography (PET/CT) has emerged as a valuable adjunct to conventional imaging modalities in the management of patients with a variety of gastrointestinal (GI) malignancies. The fusion of functional and anatomic imaging provides a unique insight into tumor biology and as a result PET/CT has become an important modality for tumor staging, response assessment to therapy and disease surveillance.

Abstract

The dual functional and anatomic imaging capability and its ability for whole body staging has established [¹⁸F]FDG-PET/CT as an integral part of the management of several GI malignancies. [¹⁸F]FDG-PET/CT has a proven role in the staging of esophageal cancer, detection of colorectal cancer recurrence, and in the management of GIST and certain GI lymphomas. [¹⁸F]FDG-PET/CT has shown promise in the assessment of treatment response in esophageal and colorectal cancers and in the staging of anal cancer. Limitations to the use of [¹⁸F]FDG-PET/CT for evaluation of the GI tract include the significant overlap between normal physiologic uptake and disease, false positive uptake in inflammatory processes such as inflammatory bowel disease and diverticulitis, and diffuse bowel uptake caused by certain medications such as metformin. The purpose of this review is to outline the technical issues and current evidence for the use of [¹⁸F]FDG-PET/CT in the evaluation of GI malignancies.

Keywords

positron emission tomography, fluorodeoxyglucose, computed tomography, gastrointestinal neoplasms, review