Cancer screenings common among those with shortest life expectancies

Issue: October 25, 2014

A substantial proportion of older Americans with limited life expectancies undergo routine cancer screening despite the unlikely benefit of the tests in this population, according to study results.

“These results raise concerns about overscreening in these individuals, which not only increases health care expenditure but can lead to patient net harm,” Trevor J. Royce, MD, MS, of the University of North Carolina at Chapel Hill, and colleagues wrote.

Royce and colleagues used data from the population-based National Health Interview Survey (NIHS) from 2000 to 2010 to identify patterns of prostate, breast, cervical and colorectal cancer screenings among individuals with different life expectancies. The analysis included 27,404 participants aged 65 years and older.

Researchers used a validated mortality index specific to NIHS to categorize participants into one of four groups based on their risk for 9-year mortality: low risk (less than 25%), intermediate risk (25% to 49%), high risk (50% to 74%) or very high risk (≥75%).

Results showed 31% to 55% of individuals at very high risk for 9-year mortality reported undergoing a recent screening for one of the four designated cancers. Among that risk group, 54.6% underwent prostate cancer screening within the previous 2 years, 40.8% underwent colorectal cancer screening within the previous 5 years, 37.5% underwent breast cancer screening within the previous 2 years, and 30.6% underwent cervical cancer screening within the prior 3 years (P<.001 for all).

When researchers stratified screening rates by individuals’ 5-year mortality risks, they observed a similar trend. Among those characterized as having a ≥50% risk for 5-year mortality, screening rates were 51.6% for prostate cancer, 40.8% for colorectal cancer, 34.2% for breast cancer and 25.7% for cervical cancer.

In addition, among women who underwent hysterectomy for benign reasons, 34% to 56% reported undergoing a Pap smear within the previous 3 years.

“Creating simple and reliable ways to assess life expectancy in the clinic may allow reduction of unnecessary cancer screening, which can benefit the patient and substantially reduce health care costs,” Royce and colleagues wrote. “There is considerable need for further dissemination efforts to educate physicians and patients regarding the existing screening guidelines and potential net harm from screening in individuals with limited life expectancy.”

Despite the higher-than-expected screening rates for individuals with shorter life expectances, results of a multivariate analysis showed individuals at very high risk for 9-year mortality were significantly less likely than those in the low-risk group to be screened for prostate cancer (OR=0.65; 95% CI, 0.5-0.85), breast cancer (OR=0.43; 95%CI, 0.35-0.53) or cervical cancer (OR=0.5; 95%CI, 0.36-0.7). Those in the very high risk group were more likely to undergo colorectal cancer screening (OR=1.07; 95% CI, 0.92-1.26), but the difference was not statistically significant.

Cary P. Gross

Older age was associated with less screening for all cancer types. Individuals who were married, had more education, had insurance or had a usual place for care were more likely to be screened.

The care patterns observed in this study conflict with multiple guidelines that recommend against cancer screening in patients with short life expectancies, Cary P. Gross, MD, associate professor of internal medicine at Yale School of Medicine and director of the Cancer Outcomes, Public Policy and Effectiveness Research Center at Yale Cancer Center, wrote in an accompanying editorial.

“Other guidelines, such as those for screening colonoscopy, suggest specific screening intervals (10 years, for patients with normal findings), as well as avoiding routine screening past a specific age (75 years),” Gross wrote. “These findings are sobering given the high colorectal cancer screening rates documented by Royce and colleagues among patients with increasing age and shorter life expectancies. This new age of skepticism is providing us with critical tools to better target screening efforts. In situations in which we are uncertain about whether benefits outweigh the risks, we need to bolster our efforts to generate evidence that can inform cancer screening decisions.”

For more information:

Gross CP. JAMA Intern Med. 2014; doi:10.1001/jamainternmed.2014.3901.
Royce TJ. JAMA Intern Med. 2014;doi:10.1001/jamainternmed.2014.3895.

Disclosure: The researchers report no relevant financial disclosures.