The Next Step

I had my first appointment with my endocrinologist last week, and I like him so far.  The main reason for this appointment was to sketch out a plan for what comes next.  Although some people have to option to just monitor things going forward, since my tumor was so big (4 cm), the next step is to do radioactive iodine (RAI) treatment.

A quick lesson in thyroid function:
The thyroid uses iodine to make T3 and T4, hormones critical in the regulation of metabolism.  When levels of T3 and T4 are low, the pituitary gland secretes thyroid stimulating hormone (TSH), which, as the name suggests, tells the thyroid to get working.

How RAI treatment works:
If you provide the thyroid with a radioactive form of iodine (¹³¹I), the cells will concentrate the radioactivity and die.  If you have a healthy thyroid, this would be very bad.  If you have thyroid cancer, you can use this to eliminate any remaining thyroid cells that may or may not be cancerous.  The neat thing about this is that the thyroid is the only part in the body that uses iodine, so there are minimal side effects from this treatment.  In order to maximize the uptake of the radiation, you want to do two things:  starve the thyroid of iodine and make sure that the levels of TSH are high.  So you go on a low iodine diet and either get injections of synthetic TSH (Thyrogen) or go off of your thyroid medication to naturally elevate your TSH levels.

Because of two main factors, scheduling has been a bit of an issue.  The first complication is that my insurance will be changing on January 1.  My endo likes to send his patients to a certain health system for the treatment, but next year they will be out of network for me.  The reason that he sends people there is because the way they do the procedure, they have an easier time of getting Thyrogen, which brings us to the second complication - Thyrogen has been in short supply for a couple years.  I initially didn't want to do the treatment until January so that I could enjoy my holidays, but since I don't want to have to go off of my meds (go hypothyroid) and deal with possibly being exhausted and feeling crummy for a few weeks, we decided to try to schedule before the end of the year.  Unfortunately, as part of the low iodine diet, I found out that you can't eat fish for 4 weeks before treatment.  We eat fish at least once a week, so that put us at the week of Christmas as the earliest option.  So the plan is to wait until January and hope that I can get Thyrogen then.  If not, I'll have to go hypo and hope for the best.