ESTRO 2021 Abstract Book

S503

ESTRO 2021

Results No clinical variables significantly correlated with RIL. The most significant negative association between accumulated dose and RIL (i.e., the higher the dose, the lower the nadir ALC) was observed in extended areas in vertebrae, heart and ribs.

Figure. Axial CT views fused with: a) voxel-wise mean of BED maps for the analyzed patients; b) voxel-wise standard deviation of BED for the analyzed patients; c) map of linear combination parameter associated with accumulated dose in the generalized linear model; d) significance of correlation between the accumulated dose and RIL expressed as –log p . Conclusion The VBA blindly highlighted a relevant logarithmic relationship between the lymphocyte depletion and local dose in organs commonly considered at risk of lymphopoietic capacity impairment. These findings may help to guide effective advanced RT treatments to optimize dosimetric RIL mitigation strategies. OC-0638 Integrated radiogenomics analyses for outcome prognosis in patients with locally advanced HNSCC A. Rabasco 1,2 , A. Zwanenburg 1,3,4 , A. Linge 1,3,4,5 , F. Lohaus 1,3,4,5 , M. Grosser 6 , G. Baretton 3,4,6,7 , G. Kalinauskaite 8,9 , I. Tinhofer 8,9 , N. Guberina 10,11 , M. Guberina 10,11 , P. Balermpas 12,13 , J. von der Grün 12,13 , U. Ganswindt 14,15,16,17 , C. Belka 14,15,16 , J.C. Peecken 14,18,19 , S.E. Combs 14,18,19 , S. Böcke 20,21 , D. Zips 20,21 , M. Baumann 1,2,3,4,5,22 , E.G. Troost 1,2,3,4,5 , M. Krause 1,2,3,4,5 , S. Löck 1,3,5 1 OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; 2 Institute of Radiooncology – OncoRay, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; 3 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Dresden, Dresden, Germany; 4 National Center for Tumor Diseases (NCT), Partner Site Dresden, Dresden, Germany; 5 Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus- Technische Universität Dresden, Dresden, Germany; 6 Institute of Pathology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; 7 Tumour- and Normal Tissue Bank, University Cancer Centre (UCC), University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; 8 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Berlin, Berlin, Germany; 9 Department of Radiooncology and Radiotherapy, Charité University Medicine Berlin, Berlin, Germany; 10 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Essen, Essen, Germany; 11 Department of Radiotherapy, University Hospital Essen, Medical Faculty, University of Duisburg- Essen, Essen, Germany; 12 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Frankfurt, Frankfurt, Germany; 13 Department of Radiotherapy and Oncology, Goethe- University Frankfurt, Frankfurt, Germany; 14 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany; 15 Department of Radiation Oncology, Ludwig-Maximilians-Universität, Munich, Germany; 16 Clinical Cooperation Group, Personalized Radiotherapy in Head and Neck Cancer, Helmholtz Zentrum Munich, Munich, Germany; 17 Department of Radiation Oncology, Medical University of Innsbruck, innsbruck, Austria; 18 Department of Radiation Oncology, Technische Universität München, Munich, Germany; 19 Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany; 20 German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Partner Site Tübingen, Tübingen, Germany; 21 Department of Radiation Oncology, Faculty of Medicine and University Hospital Tübingen, Eberhard Karls Universität Tübingen, Tübingen, Germany; 22 German Cancer Research Center (DKFZ), Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany Purpose or Objective To assess (i) if the integration of a CT-based radiomics signature [1] with gene expression data from whole transcriptome analyses improves the prognosis of loco-regional control (LRC) in patients with locally advanced