Adolescent and young adult cancer patients found to be well represented in NCI-sponsored clinical trials
Adolescent and young adult patients (AYA) with cancer have not seen the same improvements in survival over the years as their pediatric and older adult counterparts. Some evidence has suggested that this may be due in part to low AYA participation in clinical trials, limiting progress in treating this group of patients.
But an analysis of 25 years of government-funded adult cancer clinical trials found that 8.4 percent of patients enrolled were in the AYA age range (15-39), more than double the 3, 8 percent of AYA patients among all adults with cancer nationally.
We were surprised that the representation of adolescent and young adult patients was as high as it was. AYA patients are consistently considered underrepresented in adult clinical trials.”
Joseph Unger, PhD, MS, a SWOG biostatistician and health researcher at the Fred Hutchinson Cancer Research Center and lead author of the study
The study looked at enrollment data from 444 cancer treatment trials conducted from 1996-2020 by the SWOG Cancer Research Network, a clinical cancer research group funded by the National Cancer Institute (NCI), part of the National Institutes of Health (NIH). The work has just been published in the journal Cancer.
While the average survival times for AYA cancer patients have improved, they have not kept up with the survival time seen for children with cancer or for adults aged 40 and older. Over the 1975-2014 period, survival estimates for these other two groups increased by about 0.9 percent per year, while survival for AYA patients only increased by about 0.5 percent per year.
To gain insight into study participation by this age group, the research team examined patterns of AYA enrollment in Phase I, II, and III treatment trials in the 29 cancers for which SWOG enrolled 100 or more patients over the 25-year period. The team also analyzed demographic factors and cancer types and compared them with data for older cancer patients and for AYA cancer patients in the larger population.
During the period, SWOG enrolled 84,219 patients in the studied treatment trials, with 7,109 of those patients, or 8.4 percent, in the AYA age range. Patients in cancer clinical trials are generally younger than the overall cancer patient population, and in fact, cancer patients aged 65 or older are consistently underrepresented in studies.
Researchers also found that the population of AYA patients enrolled in the studies was more racially and ethnically diverse than the population of elderly patients enrolled in those studies, although it was less diverse than the AYA cancer population in the United States in general. . About 25.0 percent of enrolled AYA patients were identified as belonging to a racial or ethnic minority group, compared with 17.2 percent of enrolled patients age 40 and older. An estimated 29.2 percent of the total US AYA cancer population belongs to a minority group.
“The greater diversity among adolescent and young adult patients is consistent with population trends in general,” said Dr. unger. “If these trends represent a greater willingness of diverse populations to participate in trials, this could hold promise for improving diversity in trials in the coming years.”
The cancers with the highest percentage of AYA participants in these 444 clinical trials were Hodgkin’s disease (67.6 percent of AYA age participants), acute lymphoblastic leukemia (51.6 percent), and acute promyelocytic leukemia (37, 1 percent). The cancer with the highest total number of AYA participants in clinical trials was breast cancer, which in 3,032 patients represented 42.9 percent of all AYA participants during the period.
dr. Unger indicated that while AYA patients were well represented in SWOG studies, their total number may not be enough for a single NCI network group to conduct AYA studies quickly. “It will still be important for the groups to work together in the future,” he said. An important example of such collaboration is SWOG which is currently working with the Children’s Oncology Group to conduct a national trial for advanced stage Hodgkin lymphoma (S1826), which is underway.
SWOG Cancer Research Network
Unge, JM, et al. (2021) Adolescent and Young Adult Enrollment in a National Cancer Institute-sponsored National Clinical Trials Network Research Group for 25 Years. Cancer. doi.org/10.1002/cncr.33855.