Impact of pre-induction therapy leukapheresis on treatment outcome in adult acute myelogenous leukemia presenting with hyperleukocytosis

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/l were scheduled to undergo leukapheresis. This represented 53 patients (median age 59 years, range 16–78 years) who underwent from 1 to 4 sets of leukapheresis (median 1). The median initial WBC count was 160×10⁹/l (range 100–480×10⁹/l). Morphologic subtypes, according to the French–American–British classification, showed 3 M0, 16 M1, 6 M2, 10 M4, 16 M5, and 2 unclassified cases of AML. In 21 patients (40%), leukapheresis did not reduce their WBC counts significantly, while 32 patients (60%) achieved a WBC count of less than 100×10⁹/l (median 71×10⁹/l) after leukapheresis. Analysis of cell cycle was performed on bone marrow (BM) and peripheral blood leukemic cells before and after leukapheresis in three cases. In two of those cases, a recruitment of BM leukemic cells in the S phase was observed after leukapheresis. The median WBC count at the time of starting chemotherapy was 85×10⁹/l (range 23–264×10⁹/l). Complete remission was achieved in 55% (95% confidence interval 40–68%). Early death occurred in two cases. Median disease-free survival was 10 months, while median overall survival was 8 months. In this study, early death rate is lower than data previously published in the literature and almost all patients could receive chemotherapy. This might suggest a benefit of initial leukapheresis in the treatment of AML presenting with hyperleukocytosis.