60% of all cancers and 70% of cancer mortality occur in people greater than 65 years of age, defining cancer as a disease of older adults. Breast cancer is no exception to this rule where almost half of all new breast cancers in the United States are diagnosed in women 65 years of age or older1. Despite the association between cancer and aging, treatment recommendations and data acquired from prospective clinical trials in older women with breast cancer are sparse. As a result, physicians and older adults have limited data to guide treatment recommendation, make dose adjustments and manage toxicities in older adults. Aging is invariably associated with changes in physiology which can impact the pharmacokinetics and pharmacodynamics of cancer therapy. The potential for increased toxic effects in the older patient becomes an important concern. Therefore, it may not be reasonable to extrapolate data regarding toxicity from clinical trials, which primarily include younger, healthier patients. In addition, the age-related impact of adjuvant therapy on the functional status and quality of life of older versus younger adults has not been rigorously evaluated, and risk factors for toxicity, other than chronological age, need to be studied among older adults receiving anthracycline and non-anthracycline based chemotherapy regimens.
The goal of this study is to prospectively describe the longitudinal trajectory of functional status, comorbidity, and quality of life from before the initiation of chemotherapy to 6 months after the completion of treatment in older (65 and older) and younger (under 65) adults. We will determine the effect of pre-treatment physical functioning on physical recovery (ie, physical function at end of chemotherapy and 6 months later) after the course of adjuvant chemotherapy. In addition, we will explore if factors other than chronological age (functional status, comorbid medical conditions, nutritional status, psychological state, cognitive function, and social support) predict which patients are more likely to experience treatment morbidity (defined as grade 3-5 toxicity, hospitalization or urgent care visits, dose reduction or delay, or premature discontinuation of the planned chemotherapy course)
