WASHINGTON, DC — Acute lymphoblastic (or lymphocytic) leukemia (ALL) occurs more often in children than in adults and has much better outcomes in youngsters. ALL accounts for about 30% of all childhood cancers and affects approximately 3,000 children and adolescents each year, with a five-year survival of 94.4% in those under age 5 and 90% in patients younger than 20 years of age.
ALL is a different story in adults, however, where it remains one of the most challenging malignancies. It comprises less than 1% of all cancer cases and has a five-year survival rate of just 43% in patients age 20 and older.
“One hypothesis for this age-based disparity is differences in treatment regimens,” said researchers at the 2023 American Society for Clinical Oncology annual meeting in Chicago, June 2-6.
As current National Comprehensive Cancer Network (NCCN) guidelines provide flexibility in the treatment of young adults with either pediatric or adult regimens, a team of researchers from the George Washington University and the Washington DC VAMC undertook a study of all veterans diagnosed with ALL since 2000 who were between the ages of 18 and 45 at diagnosis to see whether different regimens correlated with different outcomes.
To conduct the study, the team tapped the electronic medical record data in the VA Corporate Data Warehouse to identify patients diagnosed with ALL and then confirmed the diagnosis through a chart review. Ultimately, 260 patients were included in the final analysis, half of whom received a pediatric-inspired regimen.
The researchers discovered that the use of a pediatric regimen more than doubled survival, with an HR of 0.41 (p=0.001), after adjusting for obesity, Philadelphia chromosome status, ALL subtype (B, T, or mixed), and cytogenetic risk. Patients aged 30 to 45 saw similar survival gains on pediatric regimens. White patients experienced significantly improved overall survival relative to people of color (HR) .55, p=0.013) on an adjusted basis. Black patients were half as likely to receive a transplant than non-Black patients, 23% vs. 46%.
Only 7% of patients participated in a clinical trial, with those aged 30 to 45 83% less likely to be clinical trial participants. This older cohort was also 24% less likely to receive a pediatric regimen than patients aged 18 to 30.
Given the findings, use of pediatric regimens into the mid-40s may markedly improve outcomes. “This data demonstrates that treatment with a pediatric regimen significantly improves overall survival in patients up to the age of 45,” the researchers said. “The data also suggests ongoing shortcomings in treatment for young adults with ALL, especially 30 to 45-year-olds, including persistently high use of adult induction regimens, low rates of referral to clinical trials, and significant racial disparities in bone marrow transplants for Black patients.”
- McKinnell Z, Hammudi M, Tuerff D, Hamilton C, Antonio M, Diao G, Liu Shanshan, Subrahmanyam R, Jain MR. Real-world outcomes of veterans 18-45 years old with acute lymphocytic leukemia. 2023 ASCO annual meeting. June 2-6, 2023. J Clin Oncol 41, 2023 (suppl 16; abstr e18852).