Reduced tumor lysis syndrome with low dose chemotherapy for hyperleukocytic acute leukemia prior to induction therapy.

Patients with hyperleukocytic acute leukemia (HAL) can succumb to leukostasis. In an attempt to reduce its incidence, 45 patients with newly diagnosed HAL and hyperleukocytosis were administered half the conventional dose of etoposide and cytosine arabinoside (EA: 50mg/m2 daily each) until WBC counts were significantly reduced and standard induction therapy was initiated. We retrospectively reviewed their outcomes and analyzed potential factors with a logistic regression model. The incidence of early mortality (<30days) was 4.4% (2/45). Patients who achieved complete remission with induction chemotherapy had significantly lower median WBC counts (26x10(9) L-1) after low dose EA treatment than the no response patients (median WBC: 65x10(9) L-1 (P<0.05). Low dose EA treatment of HAL patients reduced WBC for both lymphoid and myeloid leukemic cells and can be considered for preemptive administration to HAL patients prior to the differential diagnosis of the acute leukemia. This approach warrants further studies as a cytoreduction therapy for HAL.