Hi revrose! I've had the RAI treatment twice (once for treatment and imaging, once just for imaging) so hoping I can answer some of your questions based solely on my own experiences (I had a lot of the same questions post-op a few years ago).

My first suggestion would be to ask your doc why they didn't recommend any further imaging. They may have a good reason, but you never know if you don't ask. That being said, it seems odd to me that they didn't have you do any follow up (my cancer was isolated to one lobe of the thyroid according to pathology and they still had me do RAI).

My experience of the RAI wasn't bad (the diet you have to stick to in order to prep is the worst part in my opinion). My course of treatment the first time was 30 mCi of I-131 (the isotope of radioactive iodine that I believe is used for treatment and imaging) and imaging a few days later. I didn't have to stay in the hospital, just couldn't be around other for the first 48 hours after taking the radioactive iodine pill (which wasn't easy with four roommates and one bathroom - I was a grad student when I got diagnosed). I had 2 thyrogen shots before taking the pill (I was told this was so I didn't need to stop taking my levothyroxine) and I think the shots messed with my appetite (a possible side effect). As for the risks of taking a radioactive material, DEFINITELY consult with your doc on that. My brief scan of the literature gave the impression that risks of developing secondary cancer are low, but of course never zero, and seem to be correlated to the dosage of radioactive iodine that they give you. There's a page that mentions it on the American thyroid association website called "THYROID CANCER An increased but small absolute risk of leukemia can be attributed to radioactive iodine therapy for thyroid cancer" (it's a summary of a meta analysis of folks with 5-16 year follow ups) if you want to look, the forum won't let me post a link to it.

Personally, I would advise you to get a second opinion if you're starting to question your doctor. I would also recommend that you question your current doc about the lack of follow up. No one can advocate for your body like you can, and you have every right to ask all the questions.

Wishing you all the best,
M