SAN ANTONIO – Breast cancer outcomes haven’t improved to nearly the same impressive extent in older women as in younger women, according to Dr. Hyman B. Muss.
The reasons for this age-related disparity in breast cancer–specific survival include the increased level of comorbidities in the elderly, the underrepresentation of geriatric patients in major clinical trials, and oncologists’ limited geriatric training, he said in his Susan G. Komen for the Cure Brinker Award Lecture for Scientific Distinction in Clinical Research.
Dr. Hyman B. Muss
While the benefits of chemotherapy are similar in seniors and younger patients, the risks of serious toxicity are greater with age, he noted. Here’s where a pretreatment geriatric assessment to identify clinical predictors of morbidity and mortality can be enormously helpful, said Dr. Muss, professor of medicine and director of the geriatric oncology program at the University of North Carolina, Chapel Hill.
A growing body of data speaks to the importance of determining comorbidities to offer optimal treatment to elderly breast cancer patients. In a soon-to-be-published update of the Cancer and Leukemia Group 9343 trial of more than 600 elderly women with early breast cancer, for example, 51% of participants were still alive at the 12-year follow up. Of those who died, just 3% died of breast cancer; the other 46% died from other causes.
"If an elderly breast cancer patient in your office has high blood pressure or a blood sugar of 300 mg/dL, that’s almost more important than whether or not she gets radiation ... is cancer the patient’s major illness or is it something else, like diabetes or cardiac disease? The key thing we should be thinking of is not ‘How old are you?’ but ‘What’s your life expectancy?’ " he said.
Online tools can aid in those evaluations, including Adjuvant! Online (www.adjuvantonline.com). This tool allows one to factor comorbid conditions into clinical decisions about adjuvant therapy in women with early breast cancer. Also helpful is ePrognosis (www.eprognosis.org), which provides several scales to estimate an older community-dwelling individual’s life expectancy without breast cancer. The ePrognosis tool "can help you make a better decision about how aggressively to treat breast cancer. Some of my colleagues are doing this now in the office. It just takes a few minutes and is very user friendly," Dr. Muss said.
He said he is particularly impressed with a predictive tool developed by Dr. Arti Hurria and coworkers at the City of Hope Comprehensive Cancer Center in Duarte, Calif. This tool incorporates a brief geriatric assessment along with several laboratory test results and patient, tumor, and planned chemotherapy characteristics. The results generate a score that’s predictive of grade 3-5 chemotherapy toxicity. This predictive model performed well when tested in 500 older patients with a variety of cancers in a multicenter, prospective study conducted by the Cancer and Aging Research Group (J. Clin. Oncol. 2011;29:3457-65).
The physician’s portion of this brief geriatric assessment takes about 10 minutes and consists of three items: the Timed Up & Go test, a measure of functional status; the Blessed Orientation-Memory-Concentration test, a screen for cognitive function; and the Karnofksy performance status (KPS), a performance status measure commonly used in oncology.
The patient self-report part of the assessment takes 20-30 minutes and consists of validated scales measuring comorbidity, functional status, psychological state, social support, nutrition, and medications.
"If you’re as efficient as I am in the clinic, patients have a lot of time to do this before they see you," Dr. Muss quipped.
Scores of 0-25 are possible on this brief geriatric assessment. In the 500-patient multicenter validation study, grade 3-5 chemotherapy toxicity occurred in 53% of study participants. The incidence was 30% among patients with a score of 0-5, 52% in those with a score of 6-9, 77% with a score of 10 or 11, and 89% with a score of 12-19.
Among the significant predictive variables in this study, five stood out: one or more falls in the past 6 months; hearing impairment; difficulty in walking one block; decreased social activity; and need for assistance in taking medications.
"I’ve read hundreds of history and physical exam reports and I never see those data in there," Dr. Muss observed.
Because many oncologists now rely largely upon the KPS in an effort to predict chemotherapy toxicity, the investigators compared its performance to that of the structured brief geriatric assessment. The KPS paled in comparison.
"We pride ourselves in oncology on our judgment of performance status, but the KPS was just about worthless in predicting this. I think this brief geriatric assessment tool has made a real difference," the oncologist commented.