Dr. Abdulraheem Yacoub, an MPN specialist, explains how essential thrombocythemia (ET), polycythemia vera (PV), or myelofibrosis (MF) may progress from one disease to the next, including potential signs and symptoms of MPN progression.
We have a couple of questions from the audience. This one is from Sarah. She writes, “I’ve been living with essential thrombocythemia for three years, and have been relatively stable. Of course, I’m worried about progression to PV or MF. What is my chance of progression, and what are the signs of progression?”
That’s a very good question. And unfortunately, we’re very good at describing those numbers. Unfortunately, our tools at interfering are not as good. So, in general, patients with ET, statistically speaking, have a life expectancy that is not different from their age match peers. And Sarah’s story will be not too indifferent from her sisters and her mother, in terms of what’s going to happen to her long care and her health, provided she gets good medical care. The exception to that is that there is a transformation risk. For ET we caught around a 4 percent every 10 years in which ET will actually change into a different cancer, a higher risk cancer.
Could be MF, could be MDS, could be acute leukemia. And that will be a much more serious diagnosis. So, it’s about 4 percent in 10 years. We do have a – or we extrapolate some of the data from other cancers. So, certain mutations are more favorable, certain mutations are more risky. And we try to forecast that but worried it’s really hard to predict that since it’s such a long journey with disease. The first symptoms or the findings, when patients start suspecting that their disease has changed, is that the pattern of symptoms that they have are different.
They often become worse. So, they have more constitutional symptoms, more tiredness, more fevers, more night sweats, losing weight, not being able to eat a full meal, abdominal distension, the spleen gets bigger.
So, these are some of the feelings that patients can experience that lead to this. Other objective things is when the blood tests change in a less favorable way. So, for patients with ET who always run at 800,000 platelet count, if they’re suddenly 200, and that’s in the normal range, but that’s actually not good news, because the cancer changed. And this change is not favorable. So, as the doctors run routine labs, if they see the sudden change in labs, that’s also abnormal.
If the doctor can feel that the spleen gets bigger every time, that’s also concerning. If the patients suddenly have anemia or very high white cell count or immature white cells in the blood, that’s also a concern.
So, that’s why it’s great or important to establish a baseline symptom burden. A baseline spleen, a baseline bone marrow biopsy with mutation analysis, so that patients have a clear reference point to where they started, and if things change, they can always go back to that point and compare.