Low Enrollment of Adolescents and Young Adults Onto Cancer Trials: Insights From the Community Clinical Oncology Program

Abstract

Purpose: Stagnant outcomes for adolescents and young adults (AYAs; 15 to 39 years old) with cancer are partly attributed to poor enrollment onto clinical trials. The National Cancer Institute (NCI) Community Clinical Oncology Program (CCOP) was developed to improve clinical trial participation in the community setting, where AYAs are most often treated. Further, many CCOP sites had pediatric and medical oncologists with collaborative potential for AYA recruitment and care. For these reasons, we hypothesized that CCOP sites enrolled proportionately more AYAs than non-CCOP sites onto Children's Oncology Group (COG) trials.

Methods: For the 10-year period 2004 through 2013, the NCI Division of Cancer Prevention database was queried to evaluate enrollments into relevant COG studies. The proportional enrollment of AYAs at CCOP and non-CCOP sites was compared and the change in AYA enrollment patterns assessed. All sites were COG member institutions.

Results: Although CCOP sites enrolled a higher proportion of patients in cancer control studies than non-CCOP sites (3.5% v 1.8%; P < .001), they enrolled a lower proportion of AYAs (24.1% v 28.2%, respectively; P < .001). Proportional AYA enrollment at CCOP sites decreased during the intervals 2004 through 2008 and 2009 through 2013 (26.7% v 21.7%; P < .001).

Conclusion: Despite oncology practice settings that might be expected to achieve otherwise, CCOP sites did not enroll a larger proportion of AYAs in clinical trials than traditional COG institutions. Our findings suggest that the CCOP (now the NCI Community Oncology Research Program) can be leveraged for developing targeted interventions for overcoming AYA enrollment barriers.

FIG 1.

Proportion of Children’s Oncology Group (COG) study enrollments categorized as cancer control or AYA, by institution type (2004 through 2013). Whereas proportional enrollment onto COG cancer control studies was significantly greater at CCOP than non-CCOP sites, the proportional enrollment of AYA patients was significantly lower (see Methods for calculation of cancer control and AYA proportional enrollments). The P value represents the difference in proportional cancer control or AYA enrollment between sites. AYA, adolescent and young adult; CCOP, Community Clinical Oncology Program.

FIG 2.

(A) Proportion of CCOP and non-CCOP study enrollments that were AYA, by study type and time interval. The proportional enrollment of AYAs in all COG studies and in therapeutic studies, in particular, decreased significantly during the 5-year intervals 2004 through 2008 and 2009 through 2013 (see Methods for calculation of AYA proportional enrollment). (B) Proportion of CCOP therapeutic study enrollments that were AYA, by cancer type and time interval. The proportional enrollment of AYAs in trials classified by cancer type did not change significantly during the study intervals, except for a decrease on ALL studies. (C) Proportion of non-CCOP therapeutic study enrollments that were AYA, by cancer type and time interval. The proportional enrollment of AYAs in trials classified by cancer type did not change significantly during the study intervals, except for an increase in AYA patients with AML and RMS. (D) Proportion of CCOP therapeutic study enrollments versus cancer control study enrollments that were AYA, by time interval. The proportional enrollment of AYAs onto cancer control studies at CCOP sites was significantly lower than in therapeutic studies during both 2004 through 2008 and 2009 through 2013. ALL, acute lymphoblastic leukemia; AML, acute myeloid leukemia; AYA, adolescent and young adult; CCOP, Community Clinical Oncology Program; Ewing, Ewing sarcoma; Hodgkin, Hodgkin lymphoma; NHL, non-Hodgkin lymphoma; OS, osteosarcoma; RMS, rhabdomyosarcoma.