Photo by Rhoda Baer
Young adult with cancer receiving chemotherapy
Receiving treatment at specialized cancer centers may improve survival for adolescents and young adults (AYAs) with acute leukemia, according to a study published in Cancer Epidemiology, Biomarkers & Prevention.
The study showed that, when patients were treated at specialized cancer centers, survival rates were similar for younger AYAs and children with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML).
However, older AYAs did not appear to reap the same survival benefit from receiving treatment at a specialized cancer center.
And AYAs of all ages had significantly worse survival than children if they were not treated at specialized cancer centers.
AYAs (patients ages 15 to 39) with ALL and AML have significantly worse survival outcomes than children ages 14 and under, according to study author Julie Wolfson, MD, of the University of Alabama at Birmingham.
“A much smaller percentage of AYAs with cancer are treated at specialized cancer centers than children with cancer,” she added. “We wanted to understand whether this difference in the site of cancer care is associated with the difference in survival outcomes.”
Dr Wolfson and her colleagues used data from the Los Angeles County Cancer Surveillance Program to identify patients diagnosed with ALL or AML from ages 1 to 39.
Patients were said to have been treated at a specialized cancer center if, at any age, they were cared for at any of the National Cancer Institute-designated Comprehensive Cancer Centers (CCC) in Los Angeles County or if, at the age of 21 or younger, they were cared for at any of the Children’s Oncology Group (COG) sites not designated a Comprehensive Cancer Center.
Included in the analysis were 978 patients diagnosed with ALL as a child (ages 1 to 14), 402 patients diagnosed with ALL as an AYA (ages 15 to 39), 131 patients diagnosed with AML as a child, and 359 patients diagnosed with AML as an AYA.
Seventy percent of the children with ALL and 30% of the AYAs with ALL were treated at CCC/COG sites. Seventy-four percent of the children with AML and 22% of the AYAs with AML were treated at CCC/COG sites.
Results in ALL
AYAs diagnosed with ALL at ages 15 to 21 and 22 to 29 who were treated at CCC/COG sites had comparable survival to children who were diagnosed with ALL from ages 10 to 14 and treated at CCC/COG sites. The hazard ratios (HRs) were 1.3 for the 15-21 age group (P=0.3) and 1.2 for the 22-29 age group (P=0.8).
The reference group for this analysis was 10- to 14-year-olds treated at CCC/COG sites because the researchers excluded data from children with ALL ages 1 to 9. These patients were excluded because they have significantly better survival than the other groups, potentially as a result of different disease biology.
The researchers also found that treatment at CCC/COG sites did not improve survival for 30- to 39-year-olds with ALL. The HR for them was 3.4 (P<0.001).
Likewise, all AYAs with ALL who were not treated at CCC/COG sites had worse survival than 10- to 14-year-olds treated at CCC/COG sites. The HRs were 1.9 for the 15-21 age group (P=0.005), 2.6 for the 22-29 age group (P<0.001), and 3.0 for the 30-39 age group (P<0.001).
Results in AML
For AML patients, the reference group was 1- to 14-year-olds treated at CCC/COG sites. Compared to these patients, 15- to 21-year-olds not treated at CCC/COG sites had an increased hazard of death (HR=1.7, P=0.02), whereas 15- to 21-year-olds treated at CCC/COG sites did not (HR=1.3; P=0.4).
All 22- to 39-year-olds, regardless of the site of care, had an increased hazard of death compared to the children treated at CCC/COG sites. The HR was 3.4 (P<0.001) for 22- to 39-year-olds treated at CCC/COG sites, and the HR was 3.0 (P<0.001) for 22- to 39-year-olds not treated at CCC/COG sites.
“The fact that the older AYAs did not appear to benefit from treatment at a specialized cancer center suggests to us that the biology of the disease in these patients differs from that in younger individuals,” Dr Wolfson said.
“The most important thing we can do to help these patients is to enroll them on clinical trials so that we can better understand the biology of the disease and its response to therapy.
