Leukemia With IKZF₁ Deletion Benefits From Prolonged Maintenance Therapy

MONDAY, July 31, 2023 (HealthDay News) -- For children with acute lymphoblastic leukemia (ALL), cases with IKZF₁ deletion (IKZF₁del) benefit from prolonged maintenance therapy, according to a study published online July 17 in the Journal of Clinical Oncology.

Noting that IKZF₁del ALL showed poor response to the ALL₁₀ protocol in children in the largest minimal residual disease-defined medium-risk group, accounting for a high number of overall relapses, Rob Pieters, M.D., Ph.D., from the Princess Maxima Center for Pediatric Oncology in Utrecht, Netherlands, and colleagues compared results for the ALL₁₁ protocol, which prolonged therapy for IKZF₁del from two to three years, with the ALL₁₀ protocol. A total of 819 patients with ALL were enrolled in ALL₁₁ and stratified as in ALL₁₀.

The researchers found that in ALL₁₁, the five-year overall survival, event-free survival (EFS), cumulative risk for relapse (CIR), and death in complete remission were 94.2, 89.0, 8.2, and 2.3 percent, respectively. Five-year CIR improved to 10.8 percent from 23.4 percent, and EFS improved to 87.1 percent from 72.3 percent with prolonged maintenance. In a landmark analysis at two years from diagnosis, there was a 2.9-fold reduction of CIR (25.6 to 8.8 percent) and improvement in EFS (74.4 to 91.2 percent). Reduced therapy did not negate the five-year outcomes for ETV6::RUNX₁, Down syndrome, or poor prednisone responders.

"Children with IKZF₁del ALL seem to benefit from a third year of therapy, suggesting to change therapy accordingly for this class of patients," the authors write.

Several authors disclosed ties to the pharmaceutical industry.

Abstract/Full Text