HEAD AND NECK: Edited by Joël GuigayImmune escape mechanisms in head and neck squamous cell carcinoma and implication for new immunotherapy approachMerlano, Marco C.a,b; Denaro, Nerinaa; Garrone, OrnellaaAuthor Information aMedical Oncology and Translational Research, S. Croce & Carle Teaching Hospital, Cuneo bCandiolo Cancer Center – FPO, Candiolo (Turin), Italy Correspondence to Marco C. Merlano, MD, Medical Oncology and Translational Research, S. Croce & Carle Teaching Hospital, Cuneo, Italy. Tel: +39 0171 616739; +39 348 2260261; e-mail: email@example.com Current Opinion in Oncology: May 2020 - Volume 32 - Issue 3 - p 203-209 doi: 10.1097/CCO.0000000000000623 Buy Metrics Abstract Purpose of review The aim of this review is to describe the major steps leading to the immunosuppressive tumor microenvironment and to summarize some of the new immunotherapies that interfere with these mechanisms. Recent findings Immunotherapy has improved the outcome of relapsed/metastatic head and neck squamous cell carcinoma (HNSCC). However, most patients still do not respond to treatment and median overall survival remains short with a modest rate of long-term survivors. There is a growing awareness that tumor immune-escape is a complex process that involves many redundant mechanisms other than immune check-points. They interfere with the innate immune response, activation of adaptive immune response, homing of effector T cells, their clonal expansion, viability, and efficiency. This abundance of immunosuppressive mechanisms explains the limited results achieved by immune checkpoint inhibitors. Combined treatments targeting different mechanisms of escape are in development to further improve the outcome of patients with HNSCC. Summary Many mechanisms favor tumor immune-escape. Each tumor exploits preferably some of them and the challenge is to understand which are the best targets in each tumor. This knowledge is an important tool to design future combination strategies based on strong biological rationales, which could offer better results than simple empirical combinations. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.