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Updated: Jun 3, 2026

Murine Model of Leukemia Relapse to Induction Chemotherapy for Acute Lymphoblastic Leukemia
Published on: October 17, 2025
No advantage of a rotational continuation phase in acute lymphoblastic leukemia in childhood treated with a BFM
Maria S Felice1, Jorge G Rossi, Marta S Gallego
1Department of Hematology-Oncology, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina. marisa_felice@yahoo.com.ar
Background:
Our aim was to compare two different schedules of maintenance in pediatric acute lymphoblastic leukemia (ALL) treated with a BFM-based therapy, in a randomized study: an Arm with 6-MP + MTX (with or without vincristine and dexamethasone pulses) versus a more intensive continuation phase.
Procedure:
From January 1996 to November 2002, 429 eligible children with ALL were enrolled in a protocol with BFM-based back-bone, followed by a randomized continuation phase in standard (SRG) and intermediate (IRG) risk groups. Patients were randomized between Arms A and B for SRG and B or C for IRG. Arms A and C consisted of 6-MP and MTX and in Arm C, six pulses of VCR and dexamethasone were added. Arm B combined four pairs of drugs rotated weekly. All risk-groups received maintenance until completing 2 years of therapy from diagnosis.
Results:
With a median follow-up of 138 (range: 96-178) months, the overall pEFS (SE) was 72 (6)% for all patients and the different risk groups showed: SRG: 85 (3)%, IRG: 71 (1)%, and HRG: 42 (7)% (P-value ≤ 0.0001). The pDFS (SE) according to the assigned arm of maintenance was, for Arm A: 89 (3)% and for Arm B: 85 (4)% in SRG, and, for Arm B: 77 (4)% and for Arm C: 75 (4)% in IRG, at 10 years follow-up. There were no statistically significant differences in outcome between arms of maintenance for both risk groups.
Conclusions:
In protocols with initial BFM-based strategy, a more intensive continuation phase did not benefit any risk group of patients.

