AML: Chemo or Bone Marrow Transplant Decision

This post is regarding my specific treatment plan for my AML. When it comes to AML, there are pretty straightforward options, chemo or bone marrow transplant. This post covers why I am going on with chemo and why others would be on to a marrow transplant by now.

I had a great conversation with Dr. Kelly McCaul from Avera McKennan prior to beginning round 3 of my chemo, he helped lay everything out for me.

First let me put a little disclaimer on the statistics I will use through this post. The median age for AML patients is around 65, the younger a patient is, the better the response. So keep in mind that these statistics include all AML patients. Also, AML is rare, the studies have been quite small and can take years to get collect and process. Often current treatments are well ahead of the studies.

With the chemo regimen we are on, there is a 33% chance that it will eliminate the cancer and that I will be "cured". Cured means that the cancer does not return within 5 years. That leaves a 66% chance that I will relapse within that time. AML typically relapses quickly, within the first year or so, so each year that passes greatly reduces my chances or relapse. For some patients, the chemo doesn't achieve remission. I was in remission after my first treatment, which, along with my age (32), I like to think improves my odds. I also did not have any adverse reactions to the treatments themselves, no rejection of blood or platelet transfusions.

Before I move on to the transplants, I need to provide some background on cytogenetics. Cytogenetics is used as a guideline to predict how likely a specific patient is to relapse. With technology what it is today, doctors can look at the genetic makeup of the leukemia cell itself. There are specific abnormalities that indicate a good, standard or poor prognosis. I, along with half of AML patients fall within the standard risk group. Generally put, this puts my 5 year survival and relapse rate at around 50%. (Remember what I said about stats before)

On to bone marrow transplants...again I need to provide some background before I can tell you why I am not doing a transplant at this time.

A bone marrow transplant is basically a stem cell transplant from the marrow of a healthy donor. Stem cells are basically blank cells which can become any type of cell. In the bone marrow these stem cells become red blood cells, white blood cells, platelets and so on. My leukemia is a result of these stem cells being released as something called "blasts". Essentially they are immature cells that have not become what they are supposed to. Over time, they replace the healthy cell types that I need to live. The A in AML stands for acute, so with AML, it can be fatal in a matter of weeks or a few months if untreated.

With a bone marrow transplant, the intent is that the donor immune system becomes mine and attacks my "foreign" cancer cells. The risk is that this new donor immune system detects my body as also being foreign and attacks it. This is called Graft vs Host disease. Bone marrow transplants are the only transplants where this is a risk. With other types of transplants the scenario is usually the other way around: the host body (immune system) attacks the donor tissue. So that's the the thing with bone marrow transplants, Graft vs Host disease is usually fatal.

The best option is a transplant from a related donor, this usually has to be a sibling. Why a sibling and not a parent or child? Since we get half our genetic makeup from each of our parents, only our siblings will have a chance at the same genetic background. Same with my kids, only half of their genetic traits come from me.

Now, I have to throw a shout out to Mr. Doug Meyer, my high school Biology\Science\Physics teacher. Remember Gregor Mendel's experiments with pea plants, and dominant and recessive traits with that grid of four squares labeled: PP, Pb, Pp, pp..... anyone? Doesn't really, matter. During my conversation with Dr. Kelly, I was able to comprehend and dare I say impress the Doc when I guessed that Jessica (my sister) probably only had a 25% chance of being a bone marrow match to me. Thanks to Mr. Meyer, not only did I get that easy A in college Biology, but much of what has been going on inside of me has been much easier to comprehend.

So why ramble on with all this genetic stuff? It all comes down to assessing the risk of a bone marrow transplant. Had my sister been a match, the likelihood of graft vs host disease or infection resulting in mortality would be around 20%. Getting marrow cells from a non related donor places the mortality risk at about 50%.

So considering my cytogenetics put me in the standard relapse catagory: if my sister was a match, the 20% mortality risk vs the long term prognosis of getting a transplant from a related donor, would have put us on the path of getting a transplant. However, she is not a match. So weighing the 33% chance that the chemo will cure me, vs the 50% mortality risk of a transplant from a non related donor, we are going with a chemo only treatment for now. My age and response to the chemo so far were also considered. Should I relapse, bone marrow transplant will be considered at that time. The way I figure it, the more time we can buy, the more opportunity for advancements in both AML and bone marrow transplants, if needed at all.

There are a few general things that I also want to note related to my diagnosis.

My AML type is M0 (M-zero) indicating that I have minimally differentiated AML. Not sure what that really means, but I have not been told that the prognosis is any different from any other AML. AML itself is rare, roughly 10,000 cases are diagnosed in a year in the US (roughly 1.2 % of cancer cases). Only 2-3 % of AML cases are my type. By my math, there are about 250 cases of my kind of AML diagnosed in the US each year.

My AML exhibited in a couple unusual ways (though not unheard of). Often white blood counts are high, mine were very low. The hip and joint pain and lymph node swelling was a bit unusual as well. Also my initial bone marrow biopsy indicated that the marrow was severely necrotic (i.e the tissue was dead). Though unusual, there is nothing here to indicate that the treatment or prognosis should be any different. In fact my marrow was determined to be healthy after the first round of chemo treatment.

Ever considered being put on the bone marrow donor registry?