DR FEINSTEIN: What are your individual practices as they pertain to leukapheresis in patients who present with high white counts? And what is your arbitrary cutoff? And then, secondarily, what is your use of hydroxyurea in those patients? And the reason I ask is because many people use hydroxyurea to bring down the white count prior to initiating induction chemotherapy as an attempt to prevent tumor lysis. And how is giving 1 chemotherapy any different than giving 2 other chemotherapies?

DR STONE: That’s a very practical and important question that I face. And even in my advanced age, I do go in the hospital if a fellow calls me with a really sick leukemic. And it’s about a 40-minute drive, so I take it seriously.

I do leukapheresis on AML patients maybe once or twice a year maximum, because I think, “Why do we do leukapheresis?” We do leukapheresis to prevent “leukostatic” complications for people with high white counts. And, of course, it’s not just the height of the white count, it’s the type of leukemia cell.

Monocytic leukemias tend to be more sticky. Myelomonocytic leukemias, they’re the ones that tend to aggregate in the microcapillaries of the cerebral and pulmonary circulations and give people funniness in the head and trouble breathing. If a person’s in extremis or can’t take hydroxyurea, I will do leukapheresis. I will do it to get the white count down to about 50,000. I’m starting hydroxyurea anyway.

So the answer in AML is, the vast majority of people who present with high white counts can be managed with hydroxyurea until you can formulate a definitive therapeutic plan. And, as a matter of fact, in the RATIFY trial, about which we spoke earlier, you were allowed to get hydroxyurea for up to 5 days while you figured out what we’ve told you, whether the patient had an FLT3 mutation or not.

And as Jorge pointed out, these people have high white counts. So to answer your question, Lyle, hydroxyurea mainly to lower the white count while we’re getting a definitive leukemic plan going and, in rare cases, where they have pulmonary or cerebral problems or they can’t take hydroxyurea or their creatinines are already elevated and you don’t want to create any tumor lysis problems/exacerbations, then I would use leukapheresis.

Module 1: Current and future approaches to targeted therapy for acute myeloid leukemia (AML)

Module 2: Other clinical issues in AML management

Module 3: Case discussions