Hi there - sorry you had to join our club but welcome and there are loads of HPV + cancers here. Most are tonsil or base of tongue and often this particular type of cancer is caught in late stages due to the location so try not to worry too much as it responds well to treatment. I'm surprised they've diagnosed it without a biopsy. Althought you said most likely - did he have reactive nodes? That's often where the cancer heads next and how it's discovered. The pet scan will tell you more but it cannot confirm cancer only a biopsy can as you probably know. A pet is like an MRI, or cat, it can show infections - inflammation etc... The best advice you can get here is - if it is confirmed to be cancer, go to a ccc - you will get the best treatment an drs who are familiar with oral cancer. Good luck... Fingers crossed its not OC - and ask questions - you work in the medical environment so you know a lot of the time you have to advocate for yourself, or have it done by a loved one. Tell your husband to eat up! Often even with a feeding tube - people lose weight during rads and chemo. I lost 22 - and I did well with he treatment by most standards.
Treatment is not fun but very doable.

Take care