I had tongue cancer, so my surgery was different, but I did go through the radiation part twice. After the surgery, about 10 days to 2 weeks from release from hospital I was back to eating pretty much normally. After radiation, about 3 weeks the first time, 2 weeks the second time.

First time around It took about a month before I went back to work part time, mostly because my energy level was trashed. Second time around seems I accidentally went back to work about a week and a half after finishing radiation.

I know everyone is different, but it seems that 10 months out is a long time unless there is extenuating circumstances.

As far as the questionable uptake on the PET, as part of the healing process the muscles tend to use up glucose, which shows up as higher uptake on PET scan. Next scan should show less.
Bob