RT Journal Article SR Electronic T1 The Society for Immunotherapy of Cancer statement on best practices for multiplex immunohistochemistry (IHC) and immunofluorescence (IF) staining and validation JF Journal for ImmunoTherapy of Cancer JO J Immunother Cancer FD BMJ Publishing Group Ltd SP e000155 DO 10.1136/jitc-2019-000155 VO 8 IS 1 A1 Janis M Taube A1 Guray Akturk A1 Michael Angelo A1 Elizabeth L Engle A1 Sacha Gnjatic A1 Shirley Greenbaum A1 Noah F Greenwald A1 Cyrus V Hedvat A1 Travis J Hollmann A1 Jonathan Juco A1 Edwin R Parra A1 Marlon C Rebelatto A1 David L Rimm A1 Jaime Rodriguez-Canales A1 Kurt A Schalper A1 Edward C Stack A1 Cláudia S Ferreira A1 Konstanty Korski A1 Ana Lako A1 Scott J Rodig A1 Emanuel Schenck A1 Keith E Steele A1 Michael J Surace A1 Michael T Tetzlaff A1 Katharina von Loga A1 Ignacio I Wistuba A1 Carlo B Bifulco A1 , YR 2020 UL http://jitc.bmj.com/content/8/1/e000155.abstract AB Objectives The interaction between the immune system and tumor cells is an important feature for the prognosis and treatment of cancer. Multiplex immunohistochemistry (mIHC) and multiplex immunofluorescence (mIF) analyses are emerging technologies that can be used to help quantify immune cell subsets, their functional state, and their spatial arrangement within the tumor microenvironment.Methods The Society for Immunotherapy of Cancer (SITC) convened a task force of pathologists and laboratory leaders from academic centers as well as experts from pharmaceutical and diagnostic companies to develop best practice guidelines for the optimization and validation of mIHC/mIF assays across platforms.Results Representative outputs and the advantages and disadvantages of mIHC/mIF approaches, such as multiplexed chromogenic IHC, multiplexed immunohistochemical consecutive staining on single slide, mIF (including multispectral approaches), tissue-based mass spectrometry, and digital spatial profiling are discussed.Conclusions mIHC/mIF technologies are becoming standard tools for biomarker studies and are likely to enter routine clinical practice in the near future. Careful assay optimization and validation will help ensure outputs are robust and comparable across laboratories as well as potentially across mIHC/mIF platforms. Quantitative image analysis of mIHC/mIF output and data management considerations will be addressed in a complementary manuscript from this task force.