Clinical StudiesManagement and Outcomes of Hematological Immune-related Adverse Events: Systematic Review and Meta-analysisWilson, Nathaniel R.*; Lockhart, Jonathan R.†; Garcia-Perdomo, Herney A.‡; Oo, Thein H.§; Rojas-Hernandez, Cristhiam M.§ Author Information *Department of Internal Medicine, The University of Texas McGovern Medical School †Department of Internal Medicine, Baylor College of Medicine §Section of Benign Hematology, The University of Texas MD Anderson Cancer Center, Houston, TX ‡Department of Surgery/Urology, University of Valle School of Medicine, Cali, Colombia N.R.W. and J.R.L. contributed equally to the data procurement, writing, and editing of this manuscript and share equal first-authorship. N.R.W. and J.R.L.: performed systematic review, initial quality review, and analysis. H.A.G.-P.: performed the statistical analysis. T.H.O. and C.M.R.-H.: conceived the study. Reprints: Cristhiam M. Rojas-Hernandez, MD, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030 (e-mail: [email protected]). Journal of Immunotherapy: January 2022 - Volume 45 - Issue 1 - p 13-24 doi: 10.1097/CJI.0000000000000390 Buy SDC Metrics Abstract Data regarding clinical outcomes and management of hematological manifestations of immune checkpoint inhibition (ICI) is limited to case reports, series, and a few retrospective reviews. We aimed to determine the rate of response of hematological immune-related adverse events (irAEs) to immunosuppressive therapy. MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to the present day. Retrospective reports were included without language restrictions. The risk of bias was evaluated with the Cochrane Collaboration’s tool. The primary outcome of this study was the rate of response to immunosuppression. Eighty studies (14 case series and 66 individual case reports) were analyzed with a total of 135 patients with ICI-related hematological irAEs. Data analysis showed an average proportional response rate to immunosuppression among hematological irAE entities of 50% (range: 25%–70%). The heterogeneity index (I2) was 0% among reports within each entity. There is a wide spectrum of hematological manifestations to ICI therapy, and to date there is no large randomized-controlled trial data to evaluate the efficacy of treatment strategies for hematological irAEs. We found a variable overall response rate to immunosuppression therapy of around 50%, without statistically significant heterogeneity among different irAE types but significant differences among the different countries of publication. Future studies evaluating the optimal dose and duration of immunosuppressive agents for patients with hematological irAEs should be undertaken. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.