The Cancer and Leukemia Group B (CALGB) 369901 trial examined how frailty and older age influence the use of adjuvant hormonal therapy for breast cancer and found that while frailty can deter the start of therapy, frail patients who had started on a regimen were not much more likely to discontinue their treatment early. The results were published in the Journal of Clinical Oncology.
Vanessa B. Sheppard, PhD, of Georgetown Lombardi Comprehensive Cancer Center in Washington, DC, and colleagues found that the odds of a prefrail or frail woman not starting an adjuvant hormonal regimen was 1.63 times higher than that of stronger patients, after adjustment for other variables (P = .013).
The prospective trial enrolled 1,062 women with a mean age of 73 who had invasive nonmetastatic estrogen receptor–positive breast cancer. Patient demographics, as well as healthcare and psychosocial data were assessed at the start of the trial, at 6 months, and then annually for up to 7 years. Frailty was measured based on a previously validated 35-item scale that grouped patients into three categories: prefrail, frail, and robust. The majority of patients (76.4%) were categorized as robust, 18.7% were prefrail, and 4.9% were frail.
Factors related to non-initiation were older age (odds ratio [OR] = 1.04 for every additional year; P = .007), non-white race (OR = 1.71; P = .033), and prefrail or frail state (OR = 1.77; P < .003). The odds of non-initiation of therapy were also higher for the prefrail or frail group compared with the robust group after adjustment for race, age, and stage of disease (OR = 1.63; P = .013). The analysis showed a trend for Medicare prescription coverage being linked to start of therapy, but neither clinical provider nor clinical factors appeared to influence the decision to start treatment.
At 5 years, the therapy continuation rate was 48.5% overall and slightly lower for the frail group compared with the robust group (41% vs 50%, respectively; P = .045). There was a trend toward frail and prefrail states being a risk factor for discontinuation (hazard ratio = 1.32; P = .06). After other factors were considered in a multifactorial analysis, frailty became a non-significant factor for discontinuation (P = .15).
Factors that were significantly associated with adjuvant hormonal therapy discontinuation were older age, not being married, not owning a home, being less optimistic, and having less emotional and tangible support.
According to the authors, this is the first study to examine the role of frailty in the use of adjuvant hormonal therapy among older women.
“The finding that women who were prefrail or frail initiated therapy less often than robust women suggests that there may have been some consideration of the balance of life expectancy and the probability of recurrence within remaining life expectancy,” the authors stated in their discussion, although they do not have the patients’ life expectancy data to test this hypothesis.
Frailty is generally heterogeneous and not always directly correlated with age. Instead, frailty has to do with a patient’s daily functioning capabilities, as well as their physiologic, cognitive, and emotional reserves. “This study illustrates the potential value of considering measures of aging beyond chronologic age in understanding patterns of care for older patients with cancer. Results suggested that consideration of frailty for therapy initiation may be useful to clarify oncology treatment goals and provide data for informed decision making about the balance of benefits and risks of long-term cancer regimens among the growing older patient population,” the authors concluded.