Case-linked analysis of clinical trial enrollment among adolescents and young adults at a National Cancer Institute-designated comprehensive cancer center.

backgroundPoor accrual to cancer clinical trials may contribute to the lower improvement in survival observed for adolescents and young adults (AYAs) (those aged 15-39 years) with cancer. This has been difficult to quantify without reliable mechanisms to link incident cases with study enrollments. Using unique resources available at their National Cancer Institute-designated comprehensive cancer center, the authors compared the percentage of AYAs, children, and older adults enrolled onto cancer clinical trials and determined predictors of enrollment.

methodsPatients diagnosed with cancer from January 2008 through December 2012 at 1 pediatric and 2 adult University of Southern California hospitals were identified through the California Cancer Registry and individually linked to institutional trial enrollment databases. The availability of clinical trials was assessed.

resultsAcross the center, the enrollment percentage for AYAs (6%) was equal to that of older adults (6%), but was less than that for children (22%) (P < .01). Within the children's hospital, the AYA enrollment percentage was also less than that for children (15% vs 23%, respectively; P<.01). On multivariate analysis, diagnosis and site of care were found to be predictive of AYA enrollment onto therapeutic and nontherapeutic studies. Hispanic and Asian/Pacific Islander individuals were more likely to enroll onto nontherapeutic studies compared with non-Hispanic whites, but no racial/ethnic difference was observed for therapeutic studies.

conclusionsIn the current study, the percentages of AYAs and older adults enrolled onto therapeutic trials were low but similar. Diagnosis, site of care, and race/ethnicity appear to be predictive of enrollment. Prospective mechanisms must be instituted to capture reasons for nonenrollment of AYAs and develop corrective interventions.