Treatment Outcomes of Adolescents Compared to Younger Pediatric Patients with Acute Myeloid Leukemia: Do They Need a Special Approach?

Background: The reports of studies that compare the survival of adolescents and young adults with younger children with acute myeloid leukemia (AML) are contradictory.

Patients And Methods: We retrospectively analyzed 220 AML patients aged 0-18 years treated in pediatric oncologic centers in Poland from 2015 to 2022. The evaluated group included 31 infants (below 1 year), 91 younger children (1-9.9 years), 59 older children (10-14.9 years), and 39 adolescents (15-18 years).

Results: A 5-year overall survival for adolescents was not significantly inferior compared to younger and older children (74.3 ± 7.6% vs. 80.5 ± 4.4% vs. 77.9 ± 5.1, = 0.243). However, relapse-free survival was lower in adolescents compared to younger children (76.5 ± 7.8% vs. 65.7 ± 9.0%, = 0.049), and treatment-related mortality tended to be higher (10.3% vs. 4.4%, = 0.569). In the univariate analysis, high-risk genetics [HR, 2.0 (95% CI 1.1-3.6; = 0.014)] and a leukocyte count at diagnosis above 100,000/μL [HR, 2.4 (95% CI 1.3-4.6; = 0.004)] were found to be unfavorable prognostic factors for survival.

Conclusions: Although we have not found that age over 15 years is an unfavorable factor for overall survival, the optimal approach to therapy in adolescents, as in other age groups, is to adjust the intensity of therapy to individual genetic risk and introduce targeted therapies when indicated.