Update on Enrollment of Older Adults Onto National Cancer Institute National Clinical Trials Network Trials.

Background: Older adults are a large and growing proportion of cancer cases in the United States, but concerns persist about whether older adults are adequately represented in the cancer clinical trials that test new options for treatment and cancer care.

Methods: This paper describes adult patient enrollments by age group to the National Cancer Institute's National Clinical Trials Network (NCTN) from 2016 to 2021, compares patient enrollment by age with the estimated incident cancer population across cancer types, and explores possible associations between patient age and patient race, ethnicity, and sex.

Results: This analysis found that patients aged 18 to 69 years were overrepresented in NCTN trials, whereas patients aged 70 years and older were underrepresented compared with the estimated incident cancer population. Underrepresentation of older patients was seen across cancer types. Older patients who enrolled to NCTN trials were more likely to be non-Hispanic White than the estimated incident cancer population.

Conclusions: Compared with earlier analyses, NCTN trials are enrolling greater proportions of older adults, primarily driven by higher enrollment among patients aged 65 to 74 years. There is still significant room for improvement, however, especially among patients aged 75 years and older. Additionally, patient demographics should not be viewed in isolation: older Hispanic patients, for instance, were particularly underrepresented among patients enrolled to NCTN trials. The intersection between trial enrollment and age, race, and ethnicity warrants further study so that more targeted enrollment enhancement efforts can be developed that enhance trial diversity across demographic groups.