A practical approach to PET/MRI: Common abdominal pathology in oncology

Learning Objectives 1. Review the appearance of common abdominal pathology on MRI. 2. Discuss the added value which MRI may provide to PET/CT in oncology patients. 3. Provide illustrative examples where MRI may serve as a problem-solving tool for non-revealing or confounding PET/CT in oncology patients.

Both PET and MRI are important imaging modalities that provide unique and often complementary information of significant clinical value. Hybrid PET/MRI scanners have recently become commercially available for clinical use. Knowledge of MRI, its clinical applications and the appearance of frequently encountered pathology is essential for all imaging physicians who will be involved in reading PET/MRI, whether they are trained in nuclear medicine, radiology or both. This knowledge will allow accurate correlation of PET and MR studies and help guide recommendations for follow-up imaging when appropriate. The aim of this paper is to review the MRI characteristics of commonly encountered abdominal pathology, to discuss the added or complementary value which MRI may provide to PET/CT in oncology patients, and to highlight scenarios where MRI may serve as a problem-solving tool for non-revealing or confounding PET/CT in this patient population.