Lower Intensity Intensification Therapy in Childhood ALL

SAN DIEGO – Pediatric patients with acute lymphoblastic lymphoma (ALL) at standard risk for relapse do not benefit from lower-intensity, delayed intensification therapy, according to a study presented during the plenary session of the American Society of Hematology (ASH) 58^th Annual Meeting and Exposition.¹

To evaluate the efficacy of reduced treatment burden in this group of patients with best treatment response and the lowest risk of relapse, researchers randomly assigned 1164 pediatric patients with ALL to receive protocol III or standard protocol II for delayed re-intensification. Protocol III is shorter than protocol II by 20 days, and includes 50% lower doses of vincristine, doxorubicin, and cyclophosphamide, and a 30% lower dose of dexamethasone vs standard therapy.

“Only the most favorable patients selected by excellent minimal residual disease response were randomized aiming at a reduction in cumulative doses,” said investigator Martin Schrappe, MD, department of general pediatrics, ALL-BFM Study Group, Christian-Albrechts University Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany.

After a median follow-up of 8.6 years, results showed that 90.7% of patients who received protocol III were event-free at 5 years compared with 94.7% of those given protocol II.

The cumulative incidence of relapse at 5 years was 14.3% in the protocol III group and 1.2% in the protocol II group (P = .02), though there was no significant difference in overall survival between the 2 arms.

“In B-precursor ALL, we observed 50% more relapses in less-intensively treated patients,” Dr Schrappe added.

The 8-year cumulative incidence of secondary malignancies was 1.3% with protocol III and 0.68% with protocol II, while the rate of grade 3 to 4 infections was similar between the groups.

“Any treatment modification in patients with excellent prognosis should be carried with large caution under controlled conditions,” concluded Dr Schrappe.

Reference

1. Schrappe M, Zimmerman M, Moricke A, et al. Reduced intensity delayed intensification in standard-risk patients defined by minimal residual disease in childhood acute lymphoblastic leukemia: Results of an international randomized trial in 1164 patients (trial AIEOP-BFM ALL 2000). Paper presented at: American Society of Hematology (ASH) 58^th Annual Meeting and Exposition; December 3-6, 2016; San Diego, CA.