ESTRO 2022 - Abstract Book

S919

Abstract book

ESTRO 2022

relapse pattern was compared between HPV negative and positive patients with appropriate statistics (for details, see Table 1 caption). Results Fifty-four RV:s were found in the 40 patients. Of these, 31 originated from GTV-PET, while the other RT targets (excluding any targets incorporated) harbored 7 (GTV), 9 (CTV1) and 5 (CTV-E) relapses. Two nodal relapses were found outside the RT target volumes (Table 1). No significant difference in relapse volume was found between HPV negative and positive patients (Table 1). The distribution of POI positions among HPV negative and positive patients are visualized in Figure 1. No significant difference in relapse pattern in relation to the target volumes was found (Fisher’s exact test, p=0.83). Conclusion The data do not suggest any difference in relapse pattern in relation to FDG-PET and RT target volumes between HPV negative and positive OPSCC patients. In agreement with previous findings, the majority of relapses were found in GTV- PET. 1 Due et al . “Recurrences after intensity modulated radiotherapy for head and neck squamous cell carcinoma more likely to originate from regions with high baseline [18F]-FDG uptake”. Radiother Oncol 2014;111:360-5

PO-1085 Impact of multidisciplinary target review in head and neck radiation

K. SOUSSY 1 , S. RIDAI 1 , A. GULYBAN 2 , S. BENKHALED 3 , S. BEAUVOIS 1 , Y. LEFEBVRE 4 , E. OZALP 5 , M. LEMORT 4 , M. BURGHELEA 6 , C. AL WARDI 7 , D. VAN GESTEL 1 , T. DRAGAN 1 1 Jules Bordet Institute, Radiotherapy, Brussels, Belgium; 2 Jules Bordet Institute, Medical Physics, Brussels, Belgium; 3 Jules Bordet Institut, Radiotherapy, Brussels, Belgium; 4 Jules Bordet Institute, Radiology, Brussels, Belgium; 5 Jules Bordet Institute, Nuclear medicine, Brussels, Belgium; 6 Jules Bordet Institutes, Medical physics, Brussels, Belgium; 7 Jules Bordet Institute, Radiotherapy (Research Coordinator), Brussels, Belgium Purpose or Objective Target volume delineation remains the most critical part of the radiotherapy process especially for Head and Neck cancer (HNC) patients. In this study we aim to assess the added value of a weekly, joint multidisciplinary (dedicated radiation