Legend for CECT or MRI with PET
Primary
0: Prior studies from an outside institution are not available at the time of interpretation. Request prior imaging. Addendum to be added with score 1-4 when priors become available.
1: No evidence of recurrence: routine surveillance, CECT
2: Low suspicion
       a) Superficial abnormality (skin, mucosal surface, etc): direct visual inspection 
b) Ill-defined deep abnormality with only mild FDG: short interval follow-up* or repeat PET/CECT at routine follow up
3: High suspicion (new or enlarging discrete nodule/mass with intense FDG uptake): biopsy
4: Definitive recurrence (path proven or clinical progression): no biopsy needed
 
Nodes
0: New baseline study: need priors to assign final score
1: No evidence of recurrence: routine surveillance
2: Low suspicion (residual nodal soft tissue with only mild/ intermediate FDG): short interval follow-up or repeat PET/CECT at routine follow-up
3: High suspicion (new, enlarging with intense FDG uptake): biopsy
4: Definitive recurrence (biopsy proven or clinical progression): no biopsy needed

*short interval follow- up: 3 months at some institutions

{Distant disease} - optional if interpreting whole body PET, same 1-4 categories