You must be really worried to post twice. So I will answer twice
For what it is worth, I have had two false positive PETscans that purported to show a recurrence of base of tongue cancer. My RO and the tumor board dismissed them after follow up MRIs.
what was worse in my opinion was the false negative Petscan that showed no cancer right before my cancer had come back.
The literature and studies show that for base of tongue cancer, the false positive rate is about 50% with some ancedotal reports of up to 90%. Again, these figures are just for base of tongue cancer. Petscans are extremely accurate for lymph nodes and help many patients avoid unnecessary neck dissections.
For the last three years, my entire CCC team and the tumor board and my ENT all recommended MRI/CT only so I don't have to go thru what you are going through right now.
Hope it is also a false alarm
65 yr Old Frack
Stage IV BOT T3N2M0 HPV 16+
2007:72GY IMRT(40) 8 ERBITUX No PEG
2008:CANCER BACK Salvage Surgery
25GY-CyberKnife(5) 3 Carboplatin
Apaghia /G button
2012: CANCER BACK -left tonsilar fossa
40GY-CyberKnife(5) 3 Carboplatin
Passed away 4-29-13