Minimal benefit in exchange for considerable cost, discomfort and the possibility of complications -- clearly that's a losing proposition, but that is exactly what’s happening with cancer screenings and people over age 65.
A study published in JAMA Internal Medicine looked at screening rates for four types of cancer. Each rate declined as a patient's mortality risk increased, but as many as 55 in 100 patients with a high mortality risk continued to be screened for prostate, breast, cervical and colorectal cancers. And the inappropriate use of screening tests, such as Pap tests for women who had undergone hysterectomy, also was apparent.
"A substantial proportion of the U.S. population with limited life expectancy received prostate, breast, cervical, and colorectal cancer screening that is unlikely to provide net benefit," the researchers concluded.
The harm of such overtesting, the researchers said, is that people at high risk of mortality spend money they needn’t, and are exposed to the risks of invasive procedures.
The analysis involved 27,404 people age 65 and older.
A second study, also in JAMA, showed that if practitioners shortened the time between colonoscopy screenings for colon cancer from 10 years to five, the improvement in quality of life would be minimal, and that it would cost more than $700,000 for what is known as a QALY — a quality-adjusted life year.
“A consensus exists within the medical and scientific communities,” reported MedPageToday.com, “that routine cancer screening is unlikely to benefit people who have limited life expectancy. The consensus is reflected in clinical guidelines and more recently in the American Board of Internal Medicine Foundation's Choosing Wisely program.”
Choosing Wisely is an initiative of medical professionals who want to help patients decide on care that is supported by evidence, that doesn’t duplicate other procedures they’ve had, isn’t harmful and is truly necessary. We’ve written about Choosing Wisely many times (here, here and here), and not always (but often) in glowing terms.
These studies reinforce its best motives.
The researchers wanted to see how well the “consensus” was put into practice. In the first study, they used data from the National Health Interview Survey (NHIS) collected during interviews conducted from 2000 to 2010. One main objective was to compare clinical practice with the Healthy People 2020 goal to promote evidence-based use of cancer screening. Healthy People is a federal government effort that provides science-based, 10-year national objectives for improving the health of all Americans.
The NHIS survey participants answered questions about cancer screening. Breast cancer screening was defined as a mammogram within the last 2 years, cervical cancer screening as a Pap test within the last 3 years, colorectal cancer screening as any screening test (colonoscopy, flexible sigmoidoscopy, or fecal occult blood test) within the last 5 years, and prostate cancer screening as a prostate specific antigen (PSA) test within the last 2 years.
The nine-year mortality risk was calculated for each patient/participant. The estimates factored in age, gender, smoking status, body mass index (overweight/obesity status), comorbidities (the presence of two or more coexisting medical conditions or disease processes), hospitalizations, perceived health and functional measures.
A low risk of dying within 9 years was defined as less than a 1 in 4 chance; intermediate risk was 1 to nearly 2 in 4; high risk was 1 to nearly 3 in 4; and very high risk was a greater than 3 in 4 chance.
By those measures, 8,263 participants had a low risk of death within nine years, 8,655 an intermediate risk, 6,263 a high risk and 4,223 a very high risk.
The older patient population was composed of 87% whites. Slightly more than 4 in 10 were married, 99 in 100 had health insurance, and 96 in 100 had a consistent place where they received health care. Their educational and geographic backgrounds were diverse.
The screening rates by type of cancer and mortality risk (low to very high) were:
- prostate: 64 in 100 (70% to 55%)
- breast: 63 in 100 (74% to 38%)
- cervical: 57 in 100 (70% to 31%)
- colorectal: 47 in 100 (51% to 41%)
Because some clinical guidelines go by age rather than life expectancy, the researchers also crunched the numbers by patient age. They showed that screening rates for breast cancer were 55 in 100 for patients older than 75 and 72 in 100 patients younger than 75; cervical cancer rates were 56 in 100 for women older than 65 and 3 in 4 if they were younger; colorectal cancer screening rates were 3 in 10 for patients older than 85, 46 in 100 for patients 75 to 84 and 1 in 2 for patients younger than 75.
The age analysis didn’t include prostate cancer screening because, as we’ve blogged, the United States Preventive Services Task Force recommends against routine PSA screening at any age.
Cervical cancer screening with a Pap test also was analyzed in the subgroup of women who had a hysterectomy for benign conditions (that is, problems other than cancer). Screening rates were 56 in 100 for low-risk patients, 45 in 100 for intermediate-risk patients and 1 in 3 for women who had a high mortality risk.
An increased mortality risk was associated with a reduced likelihood of screening for all but colorectal cancer. Older age was an independent predictor of a reduced likelihood of screening for all cancers. Married participants and those with higher education, insurance coverage or a consistent place for receiving health care had an increased likelihood of being screened for cancer.
The researchers said that it was tough for clinicians to assess someone’s 10-year life expectancy, so screening guidelines were “impractical” to determine a doctor’s adherence to a certain standard.
But one thing is clear: Although screenings decrease as patients age, they’re still awfully common, despite proven benefit.
The second study focused on colorectal cancer screenings using colonoscopy, in which the doctor inserts a thin, flexible tube into the rectum and up into the lower intestine to view the lining of these organs. The study subjects were 65-year-old Medicare beneficiaries with an average risk of colorectal cancer. At 55 years old, they had received a colonoscopy that was negative.
Researchers compared clinical-guideline recommendations (colonoscopy at 65 and 75) with a more frequent interval of every 3 to 5 years. They measured QALYs gained, additional colonoscopies per QALY gained and additional costs per QALY gained.
Compared with no screening, guideline-based screening colonoscopy prevented 14 cases of colorectal cancer and 7.7 cancer-specific deaths. It resulted in about 63 life years gained per 1,000 beneficiaries screened. Screening at a five-year interval led to prevention of only an additional 1.7 cases of colorectal cancer and 0.6 cancer deaths. The gain of life years per 1,000 beneficiaries screened was only 5.8.
"To achieve this relatively small added benefit, 783 additional colonoscopies had to be performed, causing 1.3 additional complications," the authors wrote.
A three-year screening interval testing people as old as 85 prevented even fewer cancers and cancer deaths. And the life years gained per 1,000 patients screened were fewer, too.
In a commentary accompanying the JAMA studies, Dr. Cary P. Gross of Yale University School of Medicine said that the results support the view that "cancer screening in the 21st century ... is losing its luster.”
"It is particularly important to question screening strategies for older persons," he wrote.
"Patients with a shorter life expectancy have less time to develop clinically significant cancers after a screening test and are more likely to die from noncancer health problems after a cancer diagnosis."
He called for patient information that helps them understand the benefits and harms they can expect from a cancer screening, based on their individual health profile. He also said the medical community should develop quality measures to address the overuse of screening tests.
We’ve been saying that for years.