Immunotherapy-related adverse effects on 18F-FDG PET/CT imaging

Abstract

18F-Fluorodeoxyglucose positron emission tomography/CT imaging plays a key role in oncological imaging including in staging, radiotherapy planning, treatment response and recurrence assessment. Immunotherapies represent a major advance in cancer therapy for a number of tumours with resulting survival benefit. However, a wide range of immune related adverse events (irAEs), some of which can be apparent on imaging, have been reported. These involve many organ systems but particularly endocrine, cutaneous and gastrointestinal systems. Early detection of irAEs is essential to aid diagnosis and management of patients and to reduce associated morbidity. In addition, it is important to not mistake treatment related effects for disease. This pictorial review aims to identify common irAEs and changes seen on 18F-fluorodeoxyglucose positron emission tomography/CT.