Wow...I just read a novel....well done. Sorry that may have been an insensitive joke, I understand you're obviously frightened but let me try and talk you back from the ledge a bit. Reading your post I think you've wound yourself up a bit.

Let me applaud you for taking all the right steps and being thorough, you have to be your own advocate, I firmly believe that. However there has to be a point if you've seen a top notch medical professional that you take their opinion and pet them ease your mind my friend. Mass General is a great facility with a well respected otolaryngology dept, if you can't take their opinion then I'm not sure where else you could get a much better one.

Keep vigilant of course if you have risk factors but it sounds like you are letting worry take over. PET scans and CTs have a fairly low false negative rate and you've had great medical opinions so let your mind ease and don't let worry win.

Good luck

Eric