Cancer in a Gerontological Context (2015)

It is time to embed the study of cancer firmly in the context of aging research. Cancer is a disease of aging. Cancer is one of the most commonly diagnosed conditions among older adults posing a threat to healthy aging. Cancer treatments also promote premature aging with negative short- and long-term survivorship implications for patients of all ages (1). The implications of aging on cancer care is one of the biggest challenges the field of oncology currently faces which will only become more acute as the population demographics continue to shift (2). At present, adults aged 65 and older account for 60% of cancer diagnoses, 69% of patients dying of cancer, and over 60% of cancer survivors (3). Despite this, evidence to inform treatment for the majority of cancer patients (older adults) is lacking. Older adults are consistently underrepresented on treatment trials and those who are enrolled are not representative of the typical multimorbid patients seen in clinics (4,5). Even when trials are designed for older adults, few collect outcomes such as maintenance of independence, physical and cognitive limitations, psychosocial well-being, or health care utilization which are critical to inform individualized treatment decisions and optimal models of care for older adults (6).

The link between aging and cancer is central to the entire cancer care continuum. Optimal cancer prevention strategies are informed by the links between aging and disease pathogenesis. Optimal cancer treatments must take into account not only how aging influences tumor biology but how tumors behave differently in the context of an aging microenvironment. We must better understand how the aging process influences the pharmacology of cancer therapeutics. We must investigate the short- and long-term side effects of treatments specifically in older patients, especially those older than 75 years who are rarely enrolled on clinical trials. We must account for the complexity of aging inclusive of multiple chronic conditions, impaired physical performance, and mild cognitive impairment. We must study the longer term effects of cancer treatments on older patients to inform survivorship management. Finally, we must consider the education of the oncology workforce. How will the principles of aging and management of complexity be incorporated into training of residents, fellows, practicing oncologists, and advanced practice providers? Presently, less than 5% of physicians, nurses, physician’s assistants, and pharmacists have geriatric specialization or certification. As an evidence base develops, we must identify strategies for dissemination.

In geriatrics and gerontology, complexity is the norm. Researchers with expertise in geriatrics and gerontology will be critical in helping address many of the unanswered questions in cancer prevention and cancer care. The four articles addressing cancer and aging in the current issue of the Journals of Gerontology are examples of the type of research needed to begin to bridge gaps in knowledge in the field of oncology. The papers span the translational spectrum from disease pathogenesis to cancer survivorship by addressing the following topics: (a) investigation of a signaling pathway that induces senescence and reduces cancer cell migration (Gao et al.), (b) the interplay between the aging microenvironment, tumor biology, and aging phenotype in the context of acute myeloid leukemia (Nip and Rao), (c) incorporation of biomarkers of frailty and senescence in cancer treatment trials (Hubbard and Jatoi), and (d) the association between receipt of cancer chemotherapy and cognitive impairment (Anstey et al.). As the aging research community continues to engage in the investigation and dissemination of cancer-related research, significant advances will be made that will improve the lives of patients threatened by cancer.