Hi JDOC

the accuracy of the PET will also depend on where the cancer was located as well as how long since radiation finished. You are right that if the PET is done too soon, healing may interfere with the results giving your friend a "false positive"

Alex also had chemotherapy before chemoradiation and had his PET scan 12 weeks after radiation finished. Alex's cancer was on his tonsil and base of tongue (BOT) which is the bit down the throat.

The difficulty with PETs is that it is not specific to cancer and also picks up the healing process, scarring and infection. Obviously,this is all going on soon after radiation. The idea of doing the PET at 12 weeks is to allow time for the healing process to settle down so the doctors can determine what is going on with the tumour.

It might help if you could give us more information about your friends condition: where was the cancer, how big was it, did the cancer travel to the lymph nodes, what was the last day of radiation?

Will you or someone close be going to the appointment with your friend? That would be a very good thing to do if you can manage it.

Good luck
Karen