Acute myeloid leukemia with high white blood cell count (WBC) is a medical emergency. A reduction of tumor burden with hydroxyurea may prevent life-threatening complications induced by straight chemotherapy. To evaluate this strategy, we reviewed medical charts of adult patients admitted to our institution from 1997 to 2011 with non-promyelocytic AML and WBC over 50 G/L. One hundred and sixty patients were included with a median WBC of 120 G/L (range 50-450), 107 patients received hydroxyurea prior to chemotherapy, and 53 received emergency induction chemotherapy (CT). Hospital mortality was lower for patients treated with hydroxyurea (34% versus 19%, p = 0.047) even after adjusting for age (p < 0.01) and initial WBC count (p = 0.02). No evidence of any difference between treatment groups in terms of WBC decline kinetics and disease free survival (p = 0.87) was found. Oral hydroxyurea prior to chemotherapy seems a safe and efficient strategy to reduce early death of hyperleukocytic AML patients.
Keywords: Acute myeloid leukemia; acute respiratory failure; hydroxyurea; hyperleukocytosis; leukostasis.