Hyman Muss, M.D.
It is important to consider quality of life and survival calculations when treating older patients with HER2-positive or triple-negative breast cancer (TNBC), according to a recent talk at the 2017 Lynn Sage Breast Cancer Symposium.
"The real question isn't how old the patient is, but what their life expectancy is," said geriatric oncologist Hyman Muss, M.D., of the University of North Carolina School of Medicine, at the symposium, which was sponsored by Northwestern University's Robert H. Lurie Comprehensive Cancer Center. "Then you calculate the risks and benefits of toxicity, and then put it all together with the defining goals of treatment. And the goal is not always longevity."
For example, while younger patients can still function reasonably well during chemotherapy and will have time to recover from side effects, older patients may be debilitated to the point where they need to move from independent to assisted living, or even full nursing home care. Moreover, patients older than 65 have significantly greater risk of being hospitalized for side effects from chemotherapy. One study showed that for some regimens, their risk was triple that of patients younger than 65.
"This is the worst thing for an older patient," Muss said. "It can be the beginning of going to a skilled nursing facility, falling and having numerous other problems." Staying out of the hospital may take priority over gaining the benefits of chemotherapy, which may be marginal any way if the patient's tumor is one cm or smaller, Muss said.
More than 40 percent of new breast cancer diagnoses are in women 65 and older. In the United States, the median age for a breast cancer diagnosis is 62 years and the median age of death is 68 years, Muss said. But there are also 3 million breast cancer survivors who are older than 65, according to the SEER database.
For older patients, Muss said, clinicians must ask two questions that they might not ask for younger ones:
- Is cancer the patient's major illness?
- What is the patient's life expectancy without cancer?
Using a life expectancy calculator from the University of California at San Francisco, Muss walked through a comparison of two patients in their late 70s. The first had excellent health according to her own assessment, had no health issues besides cancer, and lived entirely independently. Her five-year all-cause mortality risk was between 4 percent and 23 percent. The second, a former smoker, had diabetes and COPD and one hospitalization in the past year, rated her own health as fair. Her five-year mortality risk was 69 percent.
The first patient should receive the same treatment as a younger patient if her cancer is likely to recur within five years, Muss said. The second one has both a higher likelihood of dying from something else before her cancer recurs, and a higher risk of being debilitated by chemotherapy, making the treatment decision much less straightforward.
Muss recommended PREDICT,
a tool from the United Kingdom’s National Health Service that helps clinicians and patients evaluate the benefits of various treatment options following breast cancer surgery. It presents survival estimates with and without adjuvant therapies. The model takes into account all-cause mortality, and recommends adjuvant therapy only for patients with a 5 percent or greater chance of surviving for 10 years. If it's less than 3 percent, adjuvant therapy is not offered at all because the side effects exceed the potential benefit.
While healthy older patients can make treatment choices similar to younger patients, and truly frail ones may need only palliative care, there's an “in between" group that can be treated successfully with some preparation to address their potential vulnerabilities. For example, Muss strongly recommended a cardiology consult if an older patient has risk factors for congestive heart failure. Proactive beta-blockers or ACE inhibitors may help reduce toxicity during treatment.
Muss said sentinel node biopsies might be worth the time and cost to help an older patient decide whether the benefits of chemotherapy are worth the risks and the quality of life impact, especially in cases of triple-negative breast cancers where the tumor is one cm or two cm. "If they say they are absolutely never going to consider chemo, then don't do it," he said. "But sometimes when people say they will never do chemo, it's before the fact, and when they get the results it changes their mind."