Unfortunately (for me at least), the day after tomorrow I begin “Round 3” of kicking myself when I’m down: radioactive iodine therapy. Technically on Monday I begin my two week preparatory period for the treatment (which I hear is much worse than enduring the treatment itself). The purpose of the treatment is to kill any remaining thyroid cells in my body. I know what you’re thinking….they removed my entire thyroid, so how could there be thyroid cells still in there? To put it delicately, it’s because of all my slutty lymph nodes, who did and may have been pimping themselves out to my tumor.
So for yet another overly simplified medical explanation, lymph nodes are small organs of the immune system who are packed with white blood cells (which as you recall from 7th grade biology are the body’s “army against foreign invasion”). They basically travel around and screen fluids for foreign substances (aka “cooties”). Once they identify a particular cootie, they sent out antibodies to destroy it (cue triumphant music). Humans have about 500-600 of these proud soldiers, the large majority of which (about 300…or in my case 295) hang out in the neck. They also like to congregate in the groin and armpits; clearly the neck is the most coveted assignment.
When my thyroid tumor made its big “internal appearance” the lymph nodes in the area were naturally curious about it and drawn to it. This new “cluster of cells” was quite the smooth talker and soon he had gathered a crowd of “lymphies“. And while my slutty lymphies were rubbing themselves all over my tumor, they were picking up his cells, which wouldn’t be so bad, if lymph nodes didn’t travel all over the freak’n body!
Which is why thyroid cancer can return anywhere in the body…..wait, WHAT? Basically (and again, overly simplified), an infected lymph node can travel to another part of the body, rub up against it, thereby depositing cancerous thyroid cells to this new body part (be it organ, other tissue, or even bone). Once the cells attach to the cells of this other part, they can establish a blood supply and continue to grow and multiply, forming a new “thyroid” tumor it that other organ/tissue/bone. Which isn’t necessarily “bad” until the tumor begins to interfere with that part’s function and/or cause pain.
OK, but wait…so why would cancer spread to the breast or lungs still be “thyroid” cancer and not “breast” cancer or “lung” cancer? Because the cells are still thyroid cells…their genetic material continues to be that of a thyroid cell, and therefore they still are driven to act like a thyroid (even though they can’t do a thyroid’s job on their own).
I should probably also mention that cells are VERY small….very small…soooo small; people can’t make them out individually in a surgical setting. So even though Dr. McPreppy did indeed remove my entire thyroid, as well as the five slutty lymphies that were bumping up against my tumor at the time of surgery, it is likely that some cells were left behind….the most likely places would be on my esophagus and trachea (which my thyroid was stuck onto like a bow tie), in other lymph nodes, or other places where infected lymph nodes may have been (basically, I’m most likely to have remaining cells in my neck, but they could show up anywhere.) It’s like trying to track down the source of an STD from a wildly fantastic New Year’s Eve party.
My point is, there are most likely residual thyroid cells left in my body which if not destroyed could infect other parts of my body which would be bad. So we want to destroy them, as gruesome as it may be.
As I may have mentioned in earlier blogs, thyroid cells are unlike any other cell in the human body and they can be killed in a very specific way. The first technique for killing thyroid cancer cells is to remove them from the human body, but this will work with any of our cells (feel free to try this one at home; I’m presently leaving dead skin cells all over this keyboard). The second way is unique only to cells which uptake iodine, which includes thyroid cells, and that is with radioactive iodine.
But for now, and while I’m still 85% lucid, I wanted to explain in overly simplistic terms how the radioactive iodine therapy works (since this seems to be the most confusing part of my entire sad medical saga).
OK…here goes. Your pituitary gland produces a hormone cleverly named “thyroid stimulating hormone” or TSH that tells your thyroid to produce thyroid hormone (T4) [by the way, if you want to look cool in front of thyroid cancer patients, make sure to drop “TSH levels” and “T4 levels” frequently.] The T4 hormone is your body’s “gas” that allows it to do…um…most everything. Your thyroid uses iodine to make T4. Basically, no iodine, no T4….and without T4 being produced, your pituitary starts freaking out (remember you need T4 to live) and increases its production of TSH.
So without a thyroid to produce T4, the T4 levels in my body will naturally drop, and my TSH levels will increase. Remember those potential thyroid cells that could be lingering in my body? Well those guys will also be getting the pituitary’s TSH memo which basically says “WTF Thryoid! WE NEED MORE T4 – ASAP!”. So those cells will try to produce T4, but to do that they need iodine.
So this brings me to my two-week prep. period. First, I will stop taking my thyroid replacement hormone, which will cause my pituitary to have (as we said in the 1980s) “a cow” and it will start laying the heat on those remaining thyroid cells by increasing its production of TSH. And second, while getting screamed at by my pituitary the cells will be scrambling for iodine….which is why I’m going to deprive them of it for two weeks by eating a “low iodine diet” (LID).
After two weeks those thyroid cell stragglers will be totally freaking….they desperately want to make T4 but need iodine to do it and there’s not enough in my body. And so this is when we go in for the kill! On December 13th, I’ll ingest a liquid or pill full of iodine, which my thyroid cells will hopefully devour (“Yay” scream my thyroid cells…like the roach family first noticing its dandy “vacation motel”), but wait…it’s RADIOACTIVE iodine suckers!!! (RAID????). Any cell which uptakes the iodine should be destroyed. Then the radioactive isotopes break down over time and are eliminated from my body through fluid (mainly saliva, pee, & sweat) – which is while I’ll be isolated during this time (so as not to destroy the healthy thyroid cells of other people). It’s not a perfect system, but the best we currently have (and pretty much the same technique we’ve been using to fight thyroid cancer for at least the past 50 years).
So that’s why I’m having the radioactive iodine therapy, and why it takes two weeks to prepare for it, and why I’ll be going off my medication (which has been T3 by the way…but that’s not even a remotely interesting subject, so I’ll probably never bother explaining it…so just consider T3 and T4 to be “thyroid hormone”) and following a special (and cruelly restrictive) “low iodine diet” (LID). Hopefully you’re not utterly confused, or bored, or bored and confused. Either way, my work here is done!