When Should Stem Cell Transplants Be Considered for MPN Treatment?
When Should Stem Cell Transplants Be Considered for MPN Treatment? from Patient Empowerment Network on Vimeo.
Dr. Jeanne Palmer, an MPN specialist, discusses when a stem cell transplant is an appropriate treatment option and provides an overview of how risk is assessed in MPN patients.
Dr. Jeanne Palmer is a hematologist specializing in myeloproliferative neoplasms (MPNs) and bone marrow transplant at the Mayo Clinic in Arizona. Dr. Palmer also serves as Director of the Blood and Marrow Transplant Program and is Vice Chair and Section Chief for Hematology. Learn more about Dr. Palmer, here.
Understanding Treatment Options for ET, PV, and Myelofibrosis
When would you consider a stem cell transplant?
Dr. Jeanne Palmer:
So, the stem cell transplant is based on disease risk. There is a number of ways we assess disease risk.
The first two ones that were published a number of years back were the DIPSS score, which is Dynamic International Prognostic System Score, or the DIPSS Plus, which basically is the DIPSS and then you add to it a few other clinical features. This symptom score is based largely on things that we can see without even a bone marrow biopsy, so things like symptoms, age, number of white blood cells, whether somebody has anemia. And then the number of something called blasts, which is very immature white blood cells. The DIPSS Plus takes into account low platelets, need for transfusions, and chromosome abnormalities, which is the only test among that that needs to be from a bone marrow biopsy.
Now, these were created prior to Jakafi being commercially available. So, we have to take a little bit of a grain of salt with those because of the fact that Jakafi probably has changed how long people can live with this disease.
Now, more recently they’ve tried to account for these other molecular changes. So, when we take the genetic landscape of these diseases, we have the known driver mutations, so the JAK2 mutation which I have talked about, also calreticulin and MPL.
These three mutations all affect that one pathway, the JAK/STAT pathway, so they all affect the pathway that drives the disease and they are known to be kind of mutually exclusive and definitely contribute to the formation of the disease.
Some of these other mutations are called somatic mutations. They could be checked by things next generation sequencing or genetic analysis. There’s a number of different names that people use for this testing, but we look for mutations that are present and these mutations, number one, can sometimes tell us risk. So, there’s certain mutations that are high risk. Other times it can actually give us other opportunities for therapy, especially of the disease progresses. But these mutations are important to know for risk stratification. For example, if somebody has DIPSS score that is maybe not super high risk, but then they have one of these mutations, we know that that probably makes their disease a little bit more aggressive.
And that’s when we think about transplant, is when we know that the disease probably has an average life – when somebody gets to the point in their disease where we estimate their life expectancy is around five years, recognizing that we’re not very good at this. That is the type of point when we start to think about transplant. But the timing of transplant is something that’s extremely difficult and a very personalized decision. It’s something that it’s really important to understand the disease risks, how we assess them and the caveats of these disease risk assessments as we move forward planning and timing of transplant and that’s something that is, again, a very, very important discussion to have at length with your physician.
And I always recommend, there is quite a few of us out there who actually specialize in transplant for myelofibrosis and having discussions with somebody who really understands the biology of the myelofibrosis is important because it’s very different than a lot of the other diseases that are transplanted.