Paediatric ALL treatment has been standardised in Hong Kong since early 90s, and all the hospitals adopted the uniform treatment protocol. Subsequently the Hong Kong Group participated in a number of international and national clinical research studies, the latest one is CCCG 2020 ALL study.

The treatment strategy aims at improving treatment efficacy but reducing early and late toxicities. Cranial irradiation as prophylactic CNS directed treatment has been eliminated in the recent 3 studies.

There are also important changes in chemotherapy agents including the more frequent use of dexamethasone for better CNS protection and anti-leukaemic effect, pegylated asparaginase as the standard first line treatment and high dose methotrexate. With the multi-agent chemotherapy protocols, treatment side effects and complications are common but manageable. The treatment related mortality is below 5%.

However adolescents develop more significant complications and need close monitoring and treatment adjustment, the outcome of adolescents is now approaching the younger children. The paediatric inspired chemotherapy protocols have also been studied in some adult ALL studies with promising results.

AYA patients bring unique aspects to the management of asparaginase with a divergent toxicity profile from that seen in paediatric patients. We will discuss these aspect to management and the Australian experience with the use of paediatric inspired regimens in AYA patients.