As I understand the PET scan, a negative result is 99.9% diagnostic of no cancer, including the lump. If the PET scan shows a "hot spot", then it may or may not be cancer, as other tissues and processes can cause a positive result. So, it appears that the lumps on my tongue are not cancerous, at least at this point.

I am seeing the ENT again on the 27th, at which point I expect he will advise me on what we should do with the lump in terms of excision or further testing to see whether it is precancerous or just lymphoid tissue.

Jeff