Reply to S. Nagai et al [Letter]

Nagai et al1 highlight some pertinent issues related to current treatment approaches to acute promyelocytic leukemia (APL). In common with data from other cooperative groups, the recent study by the European APL Group reported by Kelaidi et al2 shows how heightened awareness of APL as a medical emergency demanding prompt administration of all-trans-retinoic acid (ATRA) and aggressive coagulation support–coupled with greater experience in prevention and management of treatment-related complications, including differentiation syndrome–has led to reductions in rates of induction death, particularly in patients with higher presenting WBC counts. Such measures were similarly implemented in the MRC AML15 (Medical Research Council [London, United Kingdom] Acute Myeloid Leukemia) trial,3 in accordance with the International European LeukemiaNet guidelines.4 However, when comparing results from different cooperative groups, it is also important to recognize that different trial entry criteria can result in large differences in reported rates of induction death.