Trial Information

Clinical and Biological Predictors of Chemotherapy Toxicity in Older Adults

Although cancer is a disease associated with aging, there is no standard tool in oncology
practice that incorporates clinical and biological factors to identify older adults with
cancer who may be more vulnerable to the toxicity of chemotherapy. It is generally
recognized that chronological age tells relatively little about an older adult's
physiological age. Oncologists allude to this when they describe an older adult as: "a
'young' 80-year-old" or "an 'old' 80-year-old," implying factors other than age contribute
to the health status of an older adult. Geriatricians address this by routinely performing a
"geriatric assessment," which measures independent clinical predictors of morbidity and
mortality in older adults. In addition, several potential biomarkers of aging have been
described that are associated with functional decline and mortality among older adults. This
study will identify whether novel biomarkers of aging can predict risk of chemotherapy
toxicity. The current proposal will fill this knowledge gap by melding the principles of
geriatrics with those of oncology to create a tool to assess the clinical and biological
risk factors for chemotherapy toxicity in older adults.

Furthermore, this study will determine the association between chemotherapy toxicity and
dose reductions and/or delays that decrease chemotherapy dose intensity. Maintenance of
chemotherapy dose intensity is necessary to maintain chemotherapy efficacy. Older adults are
at risk for chemotherapy toxicity and if this toxicity results in decreased dose intensity,
the benefits of chemotherapy will be compromised. This study will identify the association
between clinical and biological predictors of grade 2-5 toxicity and relative dose
intensity. Furthermore, this study will identify the specific dose-limiting toxicities.
These data will provide evidence-based criteria to identify those patients whose projected
risk of toxicity would limit dose intensity and compromise the efficacy of standard
treatment. These data could serve as the basis for "vulnerable elderly trials" which would
study an alternate therapy regimen in patients who are predicted to have a significant risk
of toxicity (and compromised efficacy) with the standard regimen.

This proposal unites the fields of geriatrics and oncology, incorporating geriatric
correlates of vulnerability and studying their impact in an aging oncology population. These
data will be used to develop a predictive equation for the risk of chemotherapy toxicity
that can be utilized in daily oncology practice. These data will facilitate decision-making
regarding the risks and benefits of adjuvant chemotherapy in older adults with breast cancer
and ultimately serve as a foundation on which to identify older adults at risk for
chemotherapy toxicity in order to guide interventions to decrease this risk.