New recommendations in the treatment of thyroid cancer
Kathryn E. Vinson, MS, CCRC
If you’re “lucky” enough to be diagnosed with “the good cancer” (note extreme sarcasm here), you’ve likely heard about radioactive iodine. Other than sounding scary – what exactly is it and how does it get rid of papillary and follicular carcinomas of the thyroid?
I remember when I went in to get my radioiodine pill after my thyroidectomy. After all the preliminary stuff, they lead me into a tiny room with a vacuum tube like they use at a bank drive through. I hear a “thunk” in the tube, then in comes a technician in a neck to toe lead apron. He pulls a lead box out of the drive through tube, and using tongs, pulls out a pill. He hands me this, some water, smiles and says – swallow this. Uh, okay dude – you look like someone from a bomb disposal team and you expect me to swallow that thing! Right…..
Long story short, I took the pill, went home, and despite a few unpleasant side effects, everything went just fine. Ten years later and I’m cancer free (wahoo!). For many though, its not that simple, with many folks questioning the need for radioiodine. New recommendations have been released for the use of radioactive iodine in the treatment of thyroid cancer, which may further confuse some patients. Let’s take some time today to talk about radioiodine, why its used, and what the new recommendations say.
Why radioactive iodine?
An interesting thing about iodine is that the only tissue that needs it is thyroid tissue. Iodine is a major component of thyroid hormones and they simply cannot be made without it. While other tissues may absorb iodine – they don’t use it to the extent that the thyroid does. So, in a perfect world, this is what happens: after a thyroidectomy for thyroid cancer, doctors will often recommend that the patient wait a while to start taking their thyroid replacement meds, and to also go on a low iodine diet. Why is this? Well, they want your TSH (thyroid stimulating hormone) to skyrocket. Again, why? When your body is starved for thyroid hormones, your pituitary gland senses this and produces TSH to tell your thyroid to get in gear and make some thyroid hormones. Any remaining thyroid tissue that was left in your body will be starved of iodine, and when you take the radioactive iodine pill, the remaining thyroid tissue, being stimulated by the high TSH level, will suck up that radioiodine. As this isotope of iodine is toxic, it kills the thyroid tissue that absorbed it. Any radioiodine in your body that wasn’t absorbed, is excreted in urine and feces.
As we all know, however, the world is far from perfect. The radioiodine also likes to hang out in other places such as the salivary glands (which can become quite painful during treatment), the breasts (which is why you don’t want to be nursing while going through this treatment), and the ovaries (which can lead to an early onset of menopause).
With the potential for some nasty side effects, its no wonder than many patients question the need for radioiodine after a thyroidectomy, especially if lymph nodes were clean. Researchers in Great Britain undertook the “HiLo” study to determine if a lower dose of radioiodine could be used in patients that are considered “low risk” for recurrence. There findings revealed that patients receiving a higher dose of radioiodine received no greater protection against recurrence than similarly matched patients receiving a lower dose. This is great news for thyroid cancer patients as lower doses do correlate to fewer side effects. Interestingly, they also found that patients receiving Thyrogen injections rather than going through thyroid hormone withdrawal saw statistically similar outcomes. Also amazing news for patients, and thyroid hormone withdrawal comes with its own laundry list of adverse effects.
If you or a loved one are going through thyroid cancer, know that you aren’t alone. There are some fabulous support groups out there, including some great “Closed Facebook Cancer Groups” where you can talk to those that have been there. Also, always remember to have open and honest discussions with your doctor about your treatment options!
As always, much love, many prayers, and abundant blessings to all of the warriors out there!