The Need to Improve the Evidence Base for Treating Older Adults With Cancer
In a session Saturday morning at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting (June 2, 2018; Chicago, IL), Artia Hurria, MD, FASCO, City of Hope National Medical Center (CA), detailed the current state of treatment for older patients with cancer and the reasons why further efforts are needed to improve the evidence base in this population.
Dr Hurria began her presentation by citing cancer as a disease strongly associated with aging. Currently, over 60% of cancer cases occur in individuals over the age of 65 years. By the year 2030, she continued, the largest growth in cancer instances is projected to occur in those over the age of 80 years. From 2010 to 2030, the projected rise in cancer incidence is expected to surpass 67% in patients older than 65 years.
Despite these projections, there has not been an accompanying growth in evidence-based data for this age group. From 2001 to 2011, there was limited-to-no change in age distribution of National Cancer Institute (NCI) Cooperative Group clinical treatment trials.
As a result, there is a well-documented underrepresentation of older adults in Food and Drug Administration (FDA) registration trials. The percentage of older adults with cancer and those enrolled in trials is greatest in those aged at least 75 years, Dr Hurria acknowledged, but the greatest opportunity to close the gap is in patients aged at least 70 years.
The conversation shifted toward a comparison to pediatrics and geriatrics, during which Dr Hurria explained that, “In pediatrics, chronological age is the same as functional age, but the same is not true in geriatrics.” In other words, aging is a heterogeneous process that consists of varying degrees of changes in physiology, vulnerability to toxicity, dependence in daily activities, and concern regarding long-term effects of therapy.
Dr Hurria likened the “hallmark of aging” to a “decreased physiologic reserve.” As patients become older, changes in organ function occur, often accompanied by an increase in number of comorbidities and a risk of toxicity that affects cognition and function. These factors—coupled with the high rates of cancer in the older population—signifies an increased importance of integrating geriatrics into oncology. The “geriatric assessment,” therefore, should include factors other than chronological age that predict morbidity and mortality in older adults (ie, functional status, comorbid medical conditions, nutritional status, among others).
Importantly, Dr Hurria added that the “typical” older patient—those needing assistance with daily activities and with multiple comorbid medical conditions treated through polypharmacy—likely did not participate in registration and cooperative group studies and consequently are not represented in standard treatment protocols.
Furthermore, there are multiple gaps of knowledge among geriatric clinicians and oncologists that need to be addressed, Dr Hurria stated. The Institute of Medicine, ASCO, and various other organizations have made efforts to fill knowledge gaps, including recommending increased FDA authority to incentivize and require research on older adults, suggesting improving the conduct of research and research environments to be more inclusive of older adults, and creating a “roadmap” of knowledge gaps and priority areas for research at the cancer and aging interface.
“To move things forward with clinical trials for older adults, it is really about speaking and working with one another,” Dr Hurria said.
She closed her presentation with a reference to the National Institute of Health’s Inclusion Across the Lifespan Policy, with changes toward more inclusive language for older adults.
“We are ready right now to launch and jump. If we do this together, the next 5 to 10 years could be monumental in the older population of patients,” she concluded.—Zachary Bessette