2nd MPN visit

[Wendrew]

2 white cell counts: #1. 556,000, #2 643,00. In past 2 months. No blood draw taken at this appointment. Stating my concern over those numbers, she tells me that white cell count doesn’t correlate with increased thrombosis risk. That was news to me. To address my concern she says to add 1 extra hydroxy a week. See you in 3 months. So my question is ‘ does this sound right to you guys?’ Thanks.

[hunter5582]

The issue is more complex than more WBCs = more thrombosis risk. While it appears that leukocytosis can be considered a risk factor in thrombosis, hemorrhage and overall survival, there does not appear to be any precise cutoff per this meta analysis.

An analysis on secondary outcomes was also performed. We confirmed an association between leukocytosis and bleeding both in PV and ET, but the low number of studies reporting on this factor did not allow for an estimate (RR, 1.87; 95% CI, 1.26-2.77) as precise as the one for thrombosis. We stress that the most frequent type of bleeding was gastrointestinal, followed by skin or muscle hematoma and hemarthrosis.

Concerning survival, this meta-analysis validated a survival disadvantage of patients with leukocytosis. Of note, leukocytosis, in addition to advanced age and history of thrombosis, has already been incorporated into an international prognostic score for shortened survival in ET (IPSET-survival).61

In conclusion, a 60% expected increase of thrombosis risk in the presence of leukocytosis is a consistent estimate with non-negligible clinical relevance that should be taken into account in classifying the thrombotic risk of these patients for arterial events and in ET cases. However, a consensus definition of leukocytosis for the best prediction of vascular events requires further research. To determine the WBC cutoff that provides the best prognostic accuracy, analysis on individual patient data merged in a large collective archive of patients with predefined inclusion criteria is warranted.ashpublications.org/bloodad...

Here is a bit more about leukocytosis in the context of a MPN.

ashpublications.org/blood/a...

mpnconnect.com/pdf/leukocyt...

There are various reasons for the increased risks associated with leukocytosis that have been proposed.

academic.oup.com/jleukbio/a...

ashpublications.org/blood/a...

I expect that this is a complex issue with more factors to be considered than a simple count of WBCs. The role of leukocytosis in MPNs is an issue that needs further research to better understand.

It sounds like you may lack confidence in your current hematologist. If she is a regular hematologist, you may want to consider getting a second opinion or switching care to a MPN Specialist . Here are two resources if you are interested.

mpnforum.com/tsr-the-list/

pvreporter.com/mpn-speciali...

[Wendrew in reply to hunter5582]

Thank you Hunter for that detailed reply. You’ve given me a lot of homework that I’m thrilled to do! The more information I’m able to get, the better I feel about this journey.