RT Journal Article SR Electronic T1 Immune checkpoint inhibitor related adverse effects and FDG PET/CT findings JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP jnmt.121.262151 DO 10.2967/jnmt.121.262151 A1 Schierz, Jan-Henning A1 Sarikaya, Ismet A1 Wollina, Uwe A1 Unger, Leonore A1 Sarikaya, Ali YR 2021 UL http://tech.snmjournals.org/content/early/2021/07/30/jnmt.121.262151.abstract AB Immune check-point inhibitor (ICI) treatments activate the T-cells against tumor. Activated T-cells not only attack the tumor but also healthy cells, causing an autoimmune reaction in various tissues. These immune related adverse effects (IRAE) cause 18F-fluorodeoxyglucose (FDG) uptake in various tissues due to inflammation. It is important to recognize and report these findings on FDG Positron Emission Tomography/Computed Tomography (PET/CT) studies. FDG PET helps to determine the presence, location and severity of IRAEs. In severe cases, ICI treatments are interrupted or suspended and anti-inflammatory treatments are started. FDG uptake due IRAEs may mimic metastases or disease progression. Their presence may also help predicting response to treatment and have prognostic implications. In this review article, we will provide basic information about ICI treatments, IRAEs and FDG PET/CT findings.