Adolescent and young adults (AYAs) with acute lymphoblastic leukemia (ALL) achieved superior survival benefit when treated with pediatric ALL regimens in pediatric settings compared with adult ALL regimens administered in an adult institution, according to a retrospective analysis currently appearing in Blood Advances, the Journal of the American Society of Hematology.

AYAs aged 15-39 years with ALL may receive care in either pediatric or adult cancer settings; however, superior overall survival (OS) was observed in AYA ALL patients receiving front-line treatment in a pediatric compared to an adult setting (hazard ratio [HR], 0.53, 95% confidence interval [CI], 0.37-0.76) or at a National Cancer Institute (NCI)/Children’s Oncology Group (COG) center compared with an adult setting (HR, 0.80; 95% CI, 0.66-0.96).

Statistically significant superior leukemia-specific survival (LSS) was also observed by multivariate analysis with AYAs receiving ALL care in a pediatric setting (HR, 0.51, 95% CI, 0.35-0.74) or a NCI/COG facility (LSS HR, 0.80, 95% CI, 0.65-0.97) vs an adult setting, respectively.

Dr. Lori Muffly, medical oncologist at Stanford Health Care in Palo Alto, CA, USA, and colleagues investigated the patterns of care and outcomes in AYAs with ALL using the California Cancer Registry between 2004 and 2014. They assessed sociodemographics, treatment location, and front-line therapies administered to AYAs diagnosed with ALL during this time period and used Cox regression models to determine the association of ALL treatment, institutions, and regimens with OS and LSS for the entire cohort of AYAs aged 15 to 39 years, a younger cohort of AYAs defined as <25 years, and AYAs treated in the adult cancer setting only.

AYA cancer care is highly variable with many patients receiving adult cancer regimens in an adult facility, despite recommendations advising a pediatric approach.

AYAs with ALL are often caught in the gap between pediatric and adult cancer care and may be referred to receive treatment at either an adult or a pediatric cancer center. Furthermore, if treated at an adult center, an AYA patient with ALL may receive a pediatric or adult ALL first-line treatment regimen, even though numerous review articles, society guidelines, and AYA cancer resources espouse the pediatric approach.

The 1,473 patients in this analysis had a median age at diagnosis of 22 years; 32.3% were aged 15 to 18 years, and 56.8% were less than 25 years. Two-thirds of the cohort was male and 63.7% were of Hispanic race/ethnicity.

The majority (67.7%) of patients were treated in an adult cancer setting. Of patients treated in adult settings, just one-fourth (24.8%) received a front-line pdiatric ALL regimen, and 40.7% were treated at a NCI-designated center. The treatment setting differed significantly by age, with 86.9% and 16.0% of AYA aged 15 through 18 and 19 through 24 years, respectively, treated in a pediatric setting, and >98% of AYA aged 25 through 39 years were treated in an adult setting (p<0.001).

The proportion of AYAs treated in a pediatric setting increased significantly during the study period, at 27.3% from 2004 through 2007, to 34.9% from 2012 through 2014 (p=0.002).