Markers of Aging May Improve Cancer Treatment Selection

Incorporating objective biomarkers of functional age could potentially better predict which elderly adults could tolerate cancer treatment, according to a study published in the Journal of Clinical Oncology. Such a measurement could identify those patients most at risk from side effects of cancer treatment, including increased toxicity, functional decline, decreased quality of life, and ultimately, poorer survival.

Elderly patients, the authors say, are quite heterogeneous in their physical ability to tolerate cancer therapy, but standard methods are lacking to assess this risk, as chronological age and comorbidities are not adequate determinants. In a review published Aug. 20, the authors evaluate potential biologic markers of functional aging, including chronic inflammatory markers and markers of cellular senescence.

The most studied markers are those of chronic, systemic inflammation (including C-reactive protein [CRP], tumor necrosis factor-α, and D-dimer). They are compelling because of their ease of measurement, although potentially not “ideal markers” because they are not independent of the pathology of cancer. A variety of studies have tied these markers to acceleration of the aging process, exacerbation of age-related diseases, as well as an association with clinical measures of frailty, functional decline, and a heightened risk of mortality.

“Several chronic inflammatory markers (interlukin-6, D-dimer, and CRP) . . . may have greater predictive ability among patients without baseline functional impairments, suggesting they may identify prefrail patients that may not otherwise have been identified,” write the authors, led by Joleen M. Hubbard, M.D., from the Mayo Clinic (Rochester, Minn.).

In addition to measures of systemic inflammation, circulating markers of cellular senescence, such as p16^INK4a and telomere length, have also been studied as potential biologic markers of aging.

“It is anticipated that there will be a combination or panel of markers that will have the best predictive power of end points such as toxicity, functional decline, quality of life, and survival,” the authors write. “As with the geriatric assessment, patients would potentially be placed into frailty and/or aging categories (i.e., low-, intermediate-, or high-risk groups) to predict risk for the specific end point.”

Hubbard tells DTET that a thorough clinical geriatric assessment can take two hours or more, which is increasingly not feasible in routine clinical practices. However, if markers can provide a reliable measure of frailty in seniors, an economic argument can be made for their inclusion in geriatric workups.

Takeaway: Incorporating objective measures of functional aging could become a part of clinical geriatric oncological evaluation in an attempt to better predict which elderly patients can tolerate cancer treatment.