Elena Altemus is 89 and has dementia. She often forgets her children's names, and sometimes can't recall whether she lives in Maryland or Italy.
Yet Altemus, who entered a nursing home in November, was screened for breast cancer this summer. "If the screening is not too invasive, why not?" said her daughter, Dorothy Altemus. "I want her to have the best quality of life possible."
But a growing number of geriatricians, cancer specialists and health-system analysts say there are many reasons. Such testing in the nation's oldest patients is highly unlikely to detect lethal disease, hugely expensive and more likely to harm than help since any follow-up testing and treatment is often invasive.
And yet such screening is widespread in the United States, the result of medical culture, aggressive awareness campaigns and financial incentives to doctors.
By looking for cancer in people who are unlikely to benefit, "we find something that wasn't going to hurt the patient, and then we hurt the patient," said Dr. Sei Lee, an associate professor of geriatrics at the University of California-San Francisco.
Nearly 1 in 5 women with severe cognitive impairment—including older patients like Elena Altemus—are still get regular mammograms, according to the American Journal of Public Health—even though they're not recommended for people with a limited life expectancy. And 55 percent of older men with a high risk of death over the next decade still get PSA tests for prostate cancer, according to a 2014 study in JAMA Internal Medicine.
Among people in their 70s and 80s, cancer screenings often detect slow-growing tumors that are unlikely to cause problems in patients' lifetimes. Such patients often die of something else long before their cancers would ever have become a threat, said Dr. Deborah Korenstein, chief of general internal medicine at New York's Memorial Sloan Kettering Cancer Center. Prostate cancers, in particular, are often harmless.
Patients with dementia, for example, rarely live longer than a few years.
"It generally takes about 10 years to see benefit from cancer screening, at least in terms of a mortality benefit," Korenstein said.
Enthusiasm for cancer screenings runs high among patients and doctors, both of whom tend to overestimate the benefits but underappreciate the risks, medical research shows.
In some cases, women are being screened for tumors in organs they no longer have. In a study of women over 30, nearly two-thirds who had undergone a hysterectomy got at least one cervical cancer screening, including one-third who had been screened in the past year, according to a 2014 study in JAMA Internal Medicine.
Even some patients with terminal cancer continue to be screened for other malignancies.
Nine percent of women with advanced cancer—including tumors of the lung, colon or pancreas—received mammograms and 6 percent received cervical cancer screening, according to a 2010 study of Medicare recipients over age 65. Among men on Medicare with incurable cancer, 15 percent were screened for prostate cancer.
Although screenings can extend and improve lives for healthy, younger adults, they tend to inflict more harm than good in people who are old and frail, Korenstein said. Testing can lead to anxiety, invasive follow-up procedures and harsh treatments.
"In patients well into their 80s, with other chronic conditions, it's highly unlikely that they will receive any benefit from screening, and more likely that the harms will outweigh the benefits," said Dr. Cary Gross, a professor at the Yale School of Medicine.
By screening patients near the end of life, doctors often detect tumors that don't need to be found and treated. Researchers estimate that up to two-thirds of prostate cancers are overdiagnosed, as are a third of breast tumors.
"Overdiagnosis is serious," Gross said. "It's a tremendous harm that screening has imposed. ... It's something we're only beginning to reckon with."
A variety of medical specialties—from the American College of Surgeons to the Society of General Internal Medicine—have advised doctors against screening patients with limited time to live.. For example, the American Cancer Society recommends prostate and breast cancer screenings only in patients expected to live 10 years or more.
In November, a coalition of patient advocates, employers and others included prostate screenings in men over age 75 in its list of the top five "low-value" medical procedures. Dr. A. Mark Fendrick, co-director of the coalition, referred to the five procedures as "no-brainers," arguing that health plans should consider refusing to pay for them.
Prostate cancer screening in men over 75 cost Medicare at least $145 million a year, according to a 2014 study in the journal Cancer. Mammograms in this age group cost the federal health plan for seniors more than $410 million a year, according to a 2013 study in JAMA Internal Medicine.
And while cancer screenings generally aren't expensive—a mammogram averages about $100—they can begin a series of follow-up tests and treatments that add to the total cost of care.
Most spending on unnecessary medical care stems not from rare, big-ticket items, such as heart surgeries, but cheaper services that are performed much too often, according to an October study in Health Affairs.
Many older patients expect to continue getting screened, said Dr. Mara Schonberg, an associate professor at Harvard Medical School and Boston's Beth Israel Deaconess Medical Center.
"It's jarring for someone who's been told every year to get screened and then at age 75 you tell them to stop," she said.
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