Review ArticlesImmunotherapy and Response Assessment in Malignant Glioma Neuro-oncology PerspectiveBagley, Stephen J.∗,†; Desai, Arati S.∗,†; Nasrallah, MacLean P.†,‡; O’Rourke, Donald M.†,§Author Information ∗Division of Hematology/Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA †Glioblastoma Translational Center of Excellence, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA ‡Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA §Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Address correspondence to Stephen J. Bagley, MD, MSCE, 10th Floor, Perelman Center, South Pavilion, 3400 Civic Center Blvd, Philadelphia, PA 19104. (e-mail: [email protected]). S.J.B., A.S.D., and D.M.O. are co-inventors of intellectual property licensed by the University of Pennsylvania to Novartis. S.J.B. has previously served on an Advisory Board for Northwest Biotherapeutics and has research support from Incyte Corporation. M.P.N. reports no conflicts of interest. Topics in Magnetic Resonance Imaging: April 2020 - Volume 29 - Issue 2 - p 95-102 doi: 10.1097/RMR.0000000000000233 Buy Metrics Abstract Glioblastoma (GBM) is the deadliest form of brain cancer and recurs uniformly. Despite aggressive treatment with maximal safe surgical resection, adjuvant radiation with temozolomide chemotherapy, and alternating electrical field therapy, median survival for newly diagnosed GBM remains <2 years. Novel therapies are desperately needed. Immunotherapy, which has led to significant improvement in patient outcomes across many tumor types, is currently being studied in a large number of GBM clinical trials. One of the biggest challenges in immunotherapy trials in GBM has been accurate response assessment using currently available imaging modalities, including magnetic resonance imaging. In this review, we will discuss the rationale for immunotherapy for GBM, immunotherapeutic modalities currently under clinical evaluation in GBM, and the challenges and recent advances in imaging response assessment in GBM immunotherapy. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.