Differences in survival outcomes have persisted among white, black and Hispanic children, adolescents and young adults with acute lymphoblastic leukemia, acute myelogenous leukemia and Hodgkin lymphoma, according to a retrospective analysis of SEER data.
Although survival disparities between black and white children with ALL have been nearly eliminated, other disparities exist — particularly among adolescents and young adults (AYAs) — despite decades of improvements in relative survival.
“Studies report disparities in ALL outcomes, with black and Hispanic patients having considerably lower 5-year survival than non-Hispanic whites,” Justine M. Kahn, MD, from the division of pediatric oncology and stem cell transplantation at Columbia University Medical Center, and colleagues wrote. “Similarly, survival differences based on age and race hold true in pediatric and AYA AML and Hodgkin lymphoma.”
Although the epidemiology of ALL, AML and Hodgkin lymphoma has been investigated, information on survival trends over time had been lacking.
Kahn and colleagues used the SEER database to evaluate data from black and white (n = 27,369; years 1975-2012) and white and Hispanic (n = 20,574; years 1992-2012) children aged 0 to 14 years and AYAs aged 15 to 39 years with ALL, AML and Hodgkin lymphoma.
Improvements in survival of black children with ALL have been greater than improvements for white children, thus narrowing the survival gap between these two cohorts (annual percentage change [APC], 3.01% vs. 1.37%). Five-year survival was 93.3% (95% CI, 91.3-94.9) for white children and 92% (95% CI, 82.9-96.3) for back children between 2003 and 2007.
However, researchers observed a divergence in survival among AYAs with ALL. Survival improvements were greater among white AYAs than black AYAs at 5 years (APC, 3.13% vs. 1.25%) and 10 years (3.74% vs. –1.26%).
Hispanic children and AYAs with ALL demonstrated inferior outcomes compared with white patients (10-year survival from 2000 to 2003, 34.4% vs. 79.1%).
Among those with AML, white children (5-year APC, 4.58% vs. 0.31%; 10-year APC, 5.47% vs. 0.01%) and AYAs (5-year APC, 5.10% vs. 2.07%; 10-year APC, 6.67% vs. 2.55%) experienced greater survival improvements than their black counterparts.
Among those with Hodgkin lymphoma, 10-year survivor improvements were greater for black than white children (APC, 2.4% vs. 0.81%), thus narrowing the survival gap (10-year survival for white vs. black, 92% vs. 95%). However, white AYAs had significant 10-year survival improvements, whereas black AYAs did not (APC, 0.73% vs. 0.53%).
Researchers observed no differences in outcomes between Hispanic and white children and AYAs with AML or Hodgkin lymphoma.
“Improved survival for all patients likely reflects diagnostic and therapeutic advances, such as improvements in cellular and molecular diagnostics, staging, targeted therapies, hematopoietic cell transplantation, supportive care and expansion of pediatric cooperative group trials,” Kahn and colleagues wrote. “Unequal access to these advances, as well as both biological and nonbiological factors (eg, medication adherence, disease biology and pharmacogenomics), may potentially underlie survival disparities between groups.”
The researchers acknowledged the study was limited due to the little data on disease-, treatment- and relapse-specific factors in the SEER registry.
“Particular attention should be paid to Hispanic and black children with ALL and AML because these patients continue to suffer significantly poorer outcomes in comparison with non-Hispanic white children,” they added. “Similarly, characteristics that distinguish the unique cancer burden of adolescents and young adults with ALL and AML should be investigated, and interventions aimed at improving awareness, access and quality cancer care for these patient populations should be implemented.” – by Kristie L. Kahl
Disclosures: Kahn reports no relevant financial disclosures. Please see the full study for a list of all other researchers’ relevant financial disclosures.