stopping synthroid for 6 weeks? alternatives?

[tlang]

Hi!  I am newbie here and trying to find answers regarding follow up tests ordered for my husband, age 60. I will try to be brief and concise. He was diagnosed several years ago with hypothyroidism and presented at time with large goiter, placed on synthroid by endoc. About a year later he was diagnosed with Non Hodgkins Lymphoma which presented in lung, underwent chemo then radiation with resulting elimination of cancer (goiter also disapeared after chemo) Had PET scan at that time which showed all was well. Remained hypothyroid and treated with synthroid which has been regulated by his PCP these last years, currently on .15 mg.He has recently been seen by oncologist for various complaints including weight loss, PET scan ordered. Results showed all clear except for activity/uptake whatever in the thyroid. He ordered some lab studies, a thyroid scan and a referal to endocrinologist. When the scan office called they told my husband he had to stop taking the synthroid for 6 weeks before the test. Both the oncologist and the endocrinologist are new to us. I am hoping someone in this forum might be able to advise if there isn't a better way to follow up on the abnormal activity shown on the PET scan without suffering through those 6 weeks off synthroid, and if anyone has experience with their PET scan results. Of course the concern is poss. thyroid CA, but what are other causes etc. or maybe a link that will help. I keep coming up with everything related to initial diagnosis or follow up to thyroidectomy. I don't have any lab or PET values to add. Tried to post to the MD on this site but can't catch it at right time. Thanks for any help-------T.

[jeano22383]

The shots that cynlynne are talking about are called thyrogen shots.  I am having them in a few weeks before having RAI treatment for thyroid cancer.  I don't have to go off of my meds, I just have to have two shots on the two days prior to being dosed with the rai.  Good luck with everything

[tlang]

thank you for taking the time to reply and for all the info!  t.

[cynlynne]

Hi,
I was just diagnosed with papillary thyroid cancer after having my thyroid removed.  I am not an expert on PET scans, but I have been doing some research iodine radioactive treatment to treat the cancer.  I know that I will need to be off thyroid meds for a few weeks and go on a low iodine diet.  I need to "starve" myself of anything that aids the thyroid. This allows the radioactive iodine to be absorbed by any remaining thyroid cells in my body.  I am assuming that your husband will need to go through the same process to make his PET scan successful.  

My surgeon took me off Synthroid the day of my surgery.  He placed me on Cytomel. He told me that Cytomel is fast acting and leaves the body quickly.  I will need to go off Cytomel two weeks prior to treatment vs. six weeks off the Synthroid.

I have also read of a shot that is given.  This shot eliminates the need of going off meds.  I'm not sure what the shots are called, but maybe someone here knows.  I have read that they are expensive and that some insurance companies won't cover the cost.  You might want to ask your endo about it and then call your insurance company so you won't have an expensive surprise later on.

Good Luck to you and your husband.