LEUKOCYTAPHERESIS TREATMENT FOR PATIENTS WITH ACUTE LEUKEMIA AND BLAST
CRISIS ENABLES A HIGH PERCENTAGE OF PATIENTS TO UNDERGO INDUCTION
CHEMOTHERAPY. JC Hofmann1,2, SJ Smith1, DD Kiprov1,2. 1Apheresis Care Group, Fresenius
Apheresis Services, and 2Division of Immunotherapy, California Pacific Medical Center, San Francisco,
CA.
Introduction: Several retrospective, cohort studies have demonstrated that leukocytapheresis
(leukapheresis) treatment in patients (pts) with acute leukemia and blast crisis decreases short-term
mortality rate, but does not increase overall survival. However, pts selected in these studies for
leukapheresis treatment are often sicker and have a higher underlying mortality rate (than pts who do not
receive such treatment). No randomized controlled trial assessing the efficacy of leukapheresis in acute
leukemia has been performed, and given the current standard of care it is ethically unlikely that such a
trial will be conducted.
Methods and Clinical Presentation: Between January, 2006 and September, 2009, Apheresis Care
Group (ACG) treated 1,363 pts performing 11,324 therapeutic apheresis treatments (txs). Of this patient
cohort, 107 (7.9%) pts had acute leukemia with clinical and/or laboratory evidence of blast crisis and
received leukapheresis treatment. 65 pts had acute myelogenous leukemia (AML) and received 149
leukapheresis txs; 42 pts had acute lymphoblastic leukemia (ALL) and received 135 txs. AML pts
presented with median WBC 200 x 109/L (range 66-408 x 109/L) and 86% pts had blast crisis (defined as
blast percent >75% or blast count >100 x 109/L). Median age was 56 years (6.5-85 years); 63% pts were
male. Of CNS or pulmonary symptoms (sxs) of leukostasis (CNS sxs defined as: headache, lethargy,
confusion, or visual abnormalities; pulmonary sxs defined as: shortness of breath, hypoxia, or chest x-ray
infiltrates without evidence of pneumonia), 14% pts had no sxs, 52% pts had 1 sx, and 34% pts had 2
sxs. ALL pts presented with median WBC 325 x 109/L (104-736 x 109/L) and 83% pts had blast crisis.
Median age was 23 years (4-80 years); 65% pts were male. Of sxs of leukostasis, 24% pts had no sxs,
64% pts had 1 sx, and 12% pts had 2 sxs.
Treatment: All pts received a course of leukapheresis (Lp) with the following objectives: 1) decreasing
the risk of thrombotic and hemorrhagic complications related to leukostasis, and 2) stabilizing pts for
induction chemotherapy. WBC treatment goals were defined as: WBC count (ct) <55 x 10 9/L for AML pts,
and WBC ct <80 x 109/L for ALL pts. AML pts received a median of 2 Lp txs (range 1-5 txs); ALL pts
underwent a median of 2 Lp txs (1-7 txs).
Results: Outcomes were evaluated by the percentage of pts who: 1) reached the WBC treatment goal
and, 2) received induction chemotherapy. “Improved” outcome was defined as pts who reached their
WBC treatment goal during leukapheresis therapy; “stabilized” was defined as pts who achieved >50%
reduction in WBC ct, but did not reach their WBC goal; and “unchanged” was defined as pts who
achieved neither. In the AML cohort, 77% pts improved, 22% pts stabilized, and 1% pts were unchanged.
In the ALL cohort, 64% pts improved, 33% pts stabilized, and 3% pts were unchanged. For AML pts, the
median final WBC ct was 51 x 109/L (range 17-133 x 109/L) and 92% pts received induction
chemotherapy. For ALL pts, the median final WBC ct was 74 x 109/L (range 30-294 x 109/L) and 98% pts
received induction chemotherapy. 6 (9%) AML pts and 1 (2%) ALL pt expired within 1-4 days after
completing course of leukapheresis. Of the 7 expired pts, 71% had both blast crisis and 2 sxs of
leukostasis; 43% had intracranial hemorrhage or CVA; and 86% were hypotensive, receiving mechanical
ventilation, and unable to tolerate induction chemotherapy.
Conclusion: Carefully selected patients with acute leukemia and evidence of impending thrombosis
benefit significantly from leukapheresis therapy. A limited number of treatments (median of 2 treatments)
can enable a high percentage of patients to receive induction chemotherapy and may improve short-term
clinical outcomes (in patients with a high underlying mortality rate). Leukapheresis treatments are
considered emergency procedures as they are often life saving.
Hofmann JC, Smith SJ, Kiprov DD. “Leukocytapheresis treatment for patients with acute leukemia and blast crisis
enables a high percentage of patients to undergo induction chemotherapy.” J Clin Apheresis 2010; 25 (1): 4-5.
Presented in the plenary oral presentation at the 31st Annual Meeting of the American Society For Apheresis on
May 27th, 2010 in New Orleans, LA.
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