Does leukapheresis reduce early mortality in acute myeloid leukemia, and at what white blood cell count (WBC) should we start leukapheresis, WBC > 50,000 X 109/L or WBC >100,000 x 109/L?
Yes leukapheresis reduce early mortality in case of AML.
In case of AML- WBC >100k
In case of ALL-WBC> 400K
This article has information on the topic:
Oberoi S, Lehrnbecher T, Phillips B, Hitzler J, Ethier MC, Beyene J, Sung L. Leukapheresis and low-dose chemotherapy do not reduce early mortality in acute myeloid leukemia hyperleukocytosis: a systematic review and meta-analysis. Leuk Res. 2014 Apr;38(4):460-8
A few retrospective studies have shown that immediate leukapheresis is effective in reducing early death due to leukostasis, but the above meta-analysis by Oberoi et al showed no reduction in early mortality. Leukapheresis, however has no benefit on the long-term patient outcome.
Even when leukapheresis is recommended in AML cases with WBC >100 x10(9)/L, I have not found comparative studies regarding this issue. The main benefit are reported in cases with lung and CNS involment. Cytoreduction and support mesures should not be delayed.
There is no definitive proof that leukapheresis reduces mortality in AML
There are no randomized trials to support this idea. However, some studies report the reduction in 2 - week mortality rate. You could find a related review in 2014 ASH educational book.
We must first differentiated APL from non APL ,Leukapheresis is not routinely recommended in the management of patients with high WBC counts in APL because of the difference in leukemia biology. However, in cases of potentially life-threatening leukostasis not responsive to other modalities, leukapheresis can be considered with caution.
There is no randomized study showing the benefit of leukapheresis in the management of leukostasis. There is no clear cut off for WBC count for this aim. Another point is the size of the WBCs in addition to the number of the cells. And also there is also a risk of rebound leukocytosis after leukaphersis. According to me high dose methylprednizolone or dexamethasone may be useful in these cases to decrease the WBC until the response to chemotherapy
Semra Paydas
Yes. In high leukocyte count AML patients develop hyperviscosity syndrome (caused by cell presence, contrary to this syndrome in multiple myeloma, where it is caused by mIg). If chemotherapy is given at this stage, tumor lysis usually develops and patient can die of ARDS or other complications. Therefore, it is advisable to reduce critical blast count (either by leukapheresis or, more historically, by hydroxurea). When blood count drops to safe levels, you can start induction chemotherapy. It is difficult to find any clinical trial on this issue, of course.
There are no definitive data to suggest that leukapheresis reduces early death in high white cell count acute leukaemia. That said, in selected non-APL patients with hyperviscosity syndrome, I would consider supportive measures, cytoreduction (dexamethasone for ALL, hydroxyurea +/- cytarabine for AML) together with early leukapheresis. No fixed cut-off for WCC but usually these patients will have a WCC in excess of 100.