ESTRO 2022 - Abstract Book

S917

Abstract book

ESTRO 2022

Conclusion The GTVs and corresponding PTVs were significantly larger on MRI than on CECT. This resulted in significant lack of concordance of these two volumes. Thus, IMRT plans based solely on CECT delineated target volumes could result in significant cold spots in the GTV/PTV, loss of conformity and homogeneity. Thus, target delineations for head and neck cancers should be ideally based on integration of CECT and MRI images to minimize these dose discrepancies that could result in unsatisfactory locoregional control.