MPN specialist and researcher Dr. Joseph Scandura reviews tools that are used to monitor patients with essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF), including routine blood work and symptom management
Dr. Joseph Scandura is an Associate Professor of Medicine and Scientific Director of the Silver MPN Center at Weill Cornell Medicine. Learn more about Dr. Scandura.
I would imagine monitoring patients is different for each of the MPNs. So, how are patients typically monitored over time, and let’s start with essential thrombocythemia?
Yeah. I think – again, it’s similar. You know, what’s near-term, what’s long-term? And so, in all of these diseases, thrombosis risk is a near-term risk. That’s something that I am monitoring in certain ways to help mitigate that risk. In ET and PV, I approach them similarly. Blood counts are certainly – these are diseases of the blood forming system. Certainly, monitoring blood counts I find helpful. But the reality of it is, in ET, there is not a clear linkage between blood counts and risks.
And so, I like to keep the platelet count near normal if I can. But I also recognize that it may not be worth suppressing all of the blood counts to achieve that landmark, because it’s not clear that that’s really reducing the risk any more than just having somebody on a medication that helps control the blood counts. In polycythemia vera, different blood counts are very important. The red blood cells are kind of like part of the clotting risk. We know from clinical trials that keeping the red blood cell parameters within certain ranges reduces the risk of clotting. And so, what I monitor in polycythemia vera is the hematocrit. In women, I like to keep it below 42. In men, I like to keep it below 45.
But I don’t just – I’m not a slave to the hematocrit. I am keeping an eye on the other blood counts and the other red blood cell parameters. So, for instance, what’s the size of the red blood cells? That tells me a little bit about what’s going on in the blood formation for that patient. And what’s the number of red blood cells? So, sometimes people can have very small red cells, because they’re a little iron-deficient and have a huge surplus of the number of red blood cells. And that tells me a little bit about how their blood forming system is responding to therapy.
Iron deficiency in polycythemia vera is very prominent. I personally believe it’s a very major driver of symptoms in patients who are receiving phlebotomy as part of their care. And it’s something that I monitor and really counsel patients on. My goal is to make phlebotomy independent, but it can take a while.
Everybody starts out iron-deficient, and then we take iron out of their body through blood with the phlebotomy. And that makes them more iron-deficient.
I monitor symptoms from patients, and sometimes that can tell me that their disease needs to be – their treatment needs to be tweaked a little bit, even something as simple as aspirin. People can sometimes have burning in the skin or itching that is sometimes responsive to changing the aspirin dose or how it’s given, once a day versus twice a day.
And that simple thing can be a big change for a patient who’s kind of, literally, climbing out of their skin or wishing they could and to try and find something that is helping.
I had a patient the other day. He had COVID. I said, “Oh, you should probably get this medication.” Do you have your primary care physician? Who’s taking care of you?” And he goes, “Well, to be honest with you, you’re my guy.” And so, it’s true. I see this patient a lot. And so, sometimes they forget. If I’m not paying attention to their blood pressure, the risks or treatment of diabetes, cholesterol, lipids, their screening programs for mammogram or colonoscopy, health maintenance issues, I do keep an eye on that in patients, because I do think it’s a part of the MPNs.
I think that there are excess risks for patients for some of these factors. Certainly, if you think of it as three strikes, they get a strike for having an MPN. I don’t want them to have any other strikes. So, diabetes, hypertension, those are strikes that I can potentially, at least, treat or refer them to somebody to help comanage with me. And so, that’s kind of my general approach.
What about patients who have myelofibrosis? Are they monitored more closely?
Yeah, I think it depends a little bit on the patient. Patients with early myelofibrosis often don’t have any symptoms or near-term risks much different than those from ET or PV. As the disease can progress, then some of these patients have more profound problems with symptoms, which I may be trying to find a solution to make them feel better. And also, blood counts can become more of an issue.
Transfusions in some patients who are very high white blood cell count, the spleen is often quite enlarged. Although, in my experience, most patients aren’t really bothered by the size of their spleen as the physicians are. But it is something where I think, on average, they’re monitored a little bit more closely to quite a bit more closely depending on the patient.
What happens if someone suddenly has a change in blood counts? What do you do?
Yeah. I mean, repeat it. That’s the first thing. Also, check what’s going on. It’s not uncommon in patients with MPNs that I’ll see them and the counts are a little bit out of whack, the white count is much higher than it’s been, and questioning them. “Oh, yeah. I had X, Y, or Z last week or the week before.” It used to be a upper respiratory tract infection, or they had a minor surgical procedure.
And sometimes the responses to these things can be accentuated in patients with MPNs. And so, if that’s what of this story, I certainly would repeat it and let things calm down a little. And that’s often all it is. I’m much more of a monitor of the trends. So, one-time measure doesn’t generally excite me. It might make me want to have a follow-up a little more – in a shorter period of time. Of course, it depends on what the change is. But, for most of the changes that we observe, they’re relatively minor. And I will monitor them over time.
If I see a trend where something is progressively increasing or decreasing over time, then I start thinking about what else is going on. And that’s always in the context of what’s going on with the patient. How are they feeling? What’s their physical exam like? What are the other laboratory values like?
When is a bone marrow biopsy necessary?
I would say a bone marrow biopsy is absolutely necessary at the time of diagnosis. I personally do not routinely monitor by bone marrow biopsy unless it’s part of a clinical trial.
But I do perform a bone marrow or want to look at the bone marrow morphology if there is one of these changes or at least a trend that I want a little bit more information about. And so, if – or if it’s been a very long time since somebody has had a bone marrow. If it’s been five or ten years, then sometimes I may recommend we look just so we can collect a little bit more up-to-date information.
But I don’t routinely do a bone marrow, but I will do it if there are laboratories that are kind of trending in the wrong direction, there’s symptoms, there’s physical findings that I’m just not sure about. And I think it would help me be more sure as to what’s going on and be able to discuss that with the patient. Sometimes, just to say, “Hey. Look, we were worried about this, but the bone marrow looks really good.”