b'Interpret tissueheterogeneity.CASE STUDYPredictive biomarker of response in checkpoint blockade combination therapyIMC technology identified a unique biomarker of response in this Phase 3 clinical trial of atezolizumab (anti-PD-L1) combination therapy for 280 patients with early high-risk triple-negative breast cancer. Both cellular composition and spatial organization within the tumor microenvironment were predictive of response in patients both pre- and on-treatment 13 .AB CFigure 7. Proliferating cancer and tumor microenvironment cell phenotypes predict response to immunotherapy. A) Highlights CD8+GZMB+T cell density for immunotherapy on-treatment responder with image (left) and cell phenotype masks (right). White scale bar, 50m. B, C) For subjects treated with immunotherapy, 12 epithelial and 16 cell phenotypes predicted response. The blue outline represents the strongest predictors of immunotherapy response, with the proliferative fraction of MHCI&IIhicells strongest among epithelial (cancer) cells and CD8+TCF1+T cells the strongest response predictor overall. pCR: Pathological Complete Response; RD: residual disease.'