There is no general consensus as far as post treatment scan goes, minus any absence of a suspicion for a recurrence. NCCCN guidelines recommends a 3-6 month post treatment scan only for T3-T4 disease in the oropharynx, and a few other areas, and nothing after that. Some doctors feel the palpable, visible, mirror, and scope are good enough, while others follow a more scheduled scanning, maybe based on other professional societies like otololaryncology, and have PET/CT scans around three months post treatment, followed by 6 months, and never made it past that before a recurrence, but would think the time would be greater thereafter as time goest by. Other studies showed that a PET/CT is better than a physical exam in finding cancer, and was my case this last recurrence since I have a pec flap, extensive surgery, and radiation, and it detected recurrent cancer as small as 3x7mm,, but major surgery was still needed. I believe the quote in the article was scanning was 26% , if not more, accurate.

Good luck with everything.