998-999 / 3107
Head and Neck
IV – metastatic N site
o
CT and MRI provide size information not pathology
o
Up to 50% of pathological nodes < 1 cm
o
Additional information
o
MRI diffusion weighted
o
PET
o
No research on PET vs. MRI
o
Extracapsular extension can be up to 1 cm (CTV margin)
o
High dose to N-site depend on good delineation
2015/May/29
Apisarnthanarax IJROBP, 2006