Kathy, Breathe. I am right here with you.
You dont know that this a cancer yet. You must have a biopsy done to tell you that, or not.
Kris's reocurrence was in exactly the same spot as his original tumour on the BOT. It was biopsied again with no problems, under a general anaesthetic.
Yes the MRI will help elucidate whats going on, but only a biopsy can confirm the presence of cancerous cells.
Remember too , that are many false positives following a PET.
My positive thoughts to you both,
Tammy

Caregiver/advocate to Husband Kris age 59@ diagnosis
DX Dec '10 SCC BOT T4aN2bM0 HPV+ve.Cisplatin x3 35 IMRT.
PET 6/11 clear.
R) level 2-4 neck dissection 8/1/11 to remove residual node - necrotic with NED
Feb '12 Ca back.. 3/8/12 total glossectomy/laryngectomy/bilat neck dissection/partial pharyngectomy etc. clear margins. All nodes negative for disease. PEG in.
March 2017 - 5 years disease free. Woohoo!