Postinduction Treatment for Childhood ALL
Pulses of vincristine and corticosteroid are often added to the standard maintenance backbone, although the benefit of these pulses within the context of intensive, multiagent regimens remains controversial.
Evidence (vincristine/corticosteroid pulses):
- A CCG randomized trial conducted in the 1980s demonstrated improved outcome in patients receiving monthly vincristine/prednisone pulses. A meta-analysis combining data from six clinical trials from the same treatment era showed an EFS advantage for vincristine/prednisone pulses.[44,45]
- A systematic review of the impact of vincristine plus steroid pulses from more recent clinical trials raised the question of whether such pulses are of value in current ALL treatment, which includes more intensive early therapy.
- In a multicenter randomized trial in children with intermediate-risk ALL being treated on a BFM regimen, there was no benefit associated with the addition of six pulses of vincristine/dexamethasone during the continuation phase, although the pulses were administered less frequently than in other trials in which a benefit had been demonstrated.
- A small multicenter trial of average-risk patients demonstrated superior EFS in patients receiving vincristine plus corticosteroid pulses. In this study, there was no difference in outcome based on type of steroid (prednisone vs. dexamethasone).[Level of evidence: 1iiA]
When steroid pulses are used during the maintenance phase, dexamethasone is preferred over prednisone for younger patients. [14,48]
Evidence (dexamethasone vs. prednisone):
- In a CCG study, dexamethasone was compared with prednisone for children aged 1 to younger than 10 years with lower-risk ALL.[14,48]
- Patients randomly assigned to receive dexamethasone had significantly fewer CNS relapses and a significantly better EFS rate.
- In a Medical Research Council trial, dexamethasone was compared with prednisolone during induction and maintenance therapies in both standard-risk and high-risk patients.
- The EFS and incidence of both CNS and non-CNS relapses improved with the use of dexamethasone.
The benefit of using dexamethasone in children aged 10 to 18 years requires further investigation because of the increased risk of steroid-induced osteonecrosis in this age group.[25,50]
Duration of maintenance therapy