SCT 101

Okay, for those of you waiting in suspense to learn why my stem cell transplant doesn’t really sound like a transplant (in that I will be getting my own stem cells back after chemo), here is a quick run-down on why they do it this way and how it works. 

First a quick review of Multiple Myeloma (which is what I have). It is a cancer that affects white blood cells, particularly the cells that fight infection (this is why people with M.M. are often unexplainably chronically sick before they are diagnosed, and why we get sick easier in general). Our infection fighting cells don’t work, and we don’t have as many since some of them are mutated cancer cells. The disease can cause tumors in your bones and soft tissue (I have had both), and many of the biochemical products of these cancer cells cause damage to vital organs, including the kidneys (very frequently). White blood cells (and all blood cells) start out in our bone marrow as stem cells, which then differentiate (change) into the various components of our blood (white blood cells and red blood cells). Myeloma specifically affects the plasma cells in one’s blood.

There is no cure for Multiple Myeloma. Treatment can extend one’s life significantly, in some cases up to 10 years and more (although the more typical expectancy is 3 to 5 years). Treatment includes radiation to specific tumors, and chemotherapy which is often taken orally. Understandably, long-term chemotherapy is something most patients (and doctors) prefer to avoid if possible, since it is expensive and carries with it unpleasant side effects. Stem cell transplants allow patients to slow the progression of the disease without having to continually take toxic and unpleasant medications. They are not a cure. Myeloma almost always comes back. It also mutates. So, the chemo you took a year or two ago may no longer work today.

The idea behind the stem cell transplant is simple: kill your messed up immune system and it’s cancer cells, and implant one that is cancer free (or near cancer free). There are two types of SCT: autologous (using one’s own cells) and allogeneic (using a donor’s). Using a donor’s cells is much more risky, difficult, and requires medications to be taken for life to prevent “rejection” (which in this case is called Graft vs. Host Disease). Donor transplants tend to be more effective, but the “morbidity rate” is around 5% compared to less than 1% for auto transplants. As one who begins the transplant process tomorrow, I like the odds of the auto transplant a lot better. And, keep in mind that even it’s no cake walk.

In an autologous SCT, high dose chemotherapy is given over the course of 2 days (usually). This kills just about everything in your body, including your cancer cells. Then, you are given your stem cells back and you wait around while they find their way into the marrow of your bones, and stimulate your bone marrow to start making more cells on its own. During this time you have no immune system, so anything can make you sick. Plants, dirt, a little cold germ – anything. Any fever over 99.5 or so gets you immediately admitted to the hospital. You usually have a PICC line in your arm (or central line) because your blood is drawn every day to monitor your counts (white cells, red cells, hemoglobin, etc.), and almost everyone needs IV support in the form of fluids, blood, and medication at some point. The catheter makes it easier and less painful. You are also sick from the nasty side effects of the chemo. After about a week or so, your counts slowly start to rise. Once you hit a certain number on your white blood cell count, you are considered lower risk (in terms of infection) and are released from the care of the transplant unit back to your regular oncologist. Hopefully, the transplant works, and you don’t have to take chemo anymore for a year or two. I’m not sure what the stats are on that, but I’d guess they’re about 50/50. Many patients, however, do take “maintenance therapy”, which is chemo (oral), but at much lower doses. There are, of course, patients who see no difference in their “cancer counts” after transplant, but must still struggle with the long transplant recovery process nonetheless. And start back on the chemo. Isn’t this exciting?

But I still haven’t exactly answered why and how they can use one’s own cells, have I? Here it is: I have been on chemotherapy for about 4 months now. During that time, the number of cancer cells present in my body has dropped significantly (because of the chemo), to nearly undetectable (I hope). That means that my stem cells – the cells they harvested from me two weeks ago – are as close to cancer free as they will probably ever be again. Aside from a donor, they are my best bet to symptom/chemo free living. So, here I am.

Any questions? Any additions to the info I have provided? I am by no means an expert on myeloma or medicine, so if I have something wrong or have left something out please correct me. This is, though, how I understand it, for the most part. There’s a wonderful gray area between “knowledge being power” and “ignorance being bliss”. I try like hell to stay in that gray area. It keeps me from losing my mind.

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