WYK Chan, GKS Lam, JKH Chiu, DTL Ku, KKH Ho, SY Ha; On behalf of the Hong Kong Paediatric Haematology and Oncology Study Group

Abstract

Acute promyelocytic leukaemia (APL) is a biologically and clinically distinct variant of acute myeloid leukaemia (AML). Patients often presented as a medical emergency with lethal haemorrhages. Despite high early mortality rate, APL has superior event-free survival (EFS) with prompt administration of all-trans retinoic acid (ATRA). This study is a retrospective review comparing outcomes of paediatric APL patients in Hong Kong treated with the two previously adopted protocols (HKPHOSG AML 1996 versus ICC APL 2001) over past 20 years. Total 53 eligible patients were identified, 30 and 23 were treated with HKPHOSG AML 1996 and ICC APL 2001 protocol respectively. Five-year overall survival and EFS for HKPHOSG AML 1996 versus ICC APL 2001 protocol were 80% versus 82.6% and 66.7% versus 75.1% with a median follow up period of 193.4 versus 56.7 months. To conclude, local data reveals that ATRA-based therapy demonstrate better outcome than AML-based chemotherapy in treating paediatric APL patients.