Systematic review of barriers to the recruitment of older patients with cancer onto clinical trials

Purpose Older patients are significantly underrepresented in cancer clinical trials. A literature review was undertaken to identify the barriers that impede the accrual of this vulnerable population onto clinical trials and to determine what specific strategies are needed to improve the representation of older patients in research studies. Methods A systematic literature search was undertaken using several different strategies to identify relevant articles. Results Nine of 31 relevant papers from 159 citations were included. Age is a significant barrier to recruitment; only a quarter to one third of potentially eligible older patients are enrolled onto trials. Physicians' perceptions, protocol eligibility criteria with restrictions on comorbid conditions, and functional status to optimize treatment tolerability are the most important reasons resulting in the exclusion of older patients. Other barriers include the lack of social support and the need for extra time and resources to enroll these patients. Conversely, older patients do not view their age as an important reason for refusing trials. Conclusion Specific clinical trials confined to older patients should be conducted to evaluate tumor biology, treatment tolerability, and the effect of comorbid conditions. Protocol designs, need to stratify for age and be less restrictive with respect to exclusions on functional status, comorbidity, and previous cancers, such that results are generalizable to older patients. Physician education to dispel unfounded perceptions, improved access to available clinical trials, and provision of personnel and resources to accommodate the unique requirements of an older population are possible solutions to remove the barriers of ageism.