Treatment of children with newly diagnosed acute promyelocytic leukemia with arsenic trioxide: a single center experience

Abstract

A total of 11 children (five males and six females) with hypergranular type of acute promyelocytic leukemia (APML) were treated with intravenous arsenic trioxide (As₂O₃) between December 1998 and October 2003. Eight cycles of As₂O₃ (0.15 mg/kg/day) were administered (induction, consolidation and six cycles of maintenance) over a period of 12 months. The median WBC count at diagnosis was 3400/mm³ (range: 800–9800). In all, 10 patients (91%) achieved hematological remission at a mean duration of 48 days (range: 41–60) with all 10 patients achieving molecular remission at a median duration of 81 days (range: 64–109). Toxicity was minimal with leukocytosis in six patients, ichthyosis and hyperpigmentation of skin in five and mild peripheral neuropathy in one patient. One patient who relapsed 6 months after completing therapy achieved a second hematological and molecular remission with As₂O₃. With a median follow-up of 30 months (range: 4–62), the overall (OS) survival is 91% with a relapse-free survival (RFS) of 81%. As₂O₃ achieves hematological and molecular remission in majority of newly diagnosed children with APML with minimal toxicity, but long-term follow-up is required to evaluate late effects of As₂O₃ and study the minimum dose and duration required for a sustained remission.