NIH urges new efforts to increase colorectal cancer screening

Feb 3, 2010

Colorectal cancer screening rates in the U.S. are finally on the rise, reaching more than half of the eligible screening population. But real progress on expanding access will depend on "utilizing the full range of screening options and evidence-based interventions," according to a draft statement released today by the National Institutes of Health (NIH).

Other key elements needed to increase screening rates are better access to insurance, development of effective outreach programs, and basic population-based research to learn more about the motivations for screening and barriers to obtaining it, wrote panelists at an NIH State-of-the-Science Conference under way this week in Bethesda, MD.

"In general, there has been a slow, steady upward trend in colorectal cancer screening rates within the target population (adults age 50 and older), with overall screening rates increasing from 20% to 30% in 1997 to nearly 60% in 2008, Despite this positive trend, millions of eligible people are not screened by any method," wrote the panel, which convened to address a number of questions including factors that influence the use of screening, quality control, the most effective strategies for achieving greater compliance, and resources and research needed to maximize screening population-wide.

While flexible sigmoidoscopy remains the most common screening test, colonoscopy use is rising the fastest, driven by the need for this modality to confirm and resect lesions found by several other methods including fecal occult blood testing (FOBT) and virtual colonoscopy (also known as CT colonography or CTC).

Whether colonoscopy capacity is sufficient requires additional research but may depend on using other modalities for initial screening, the panel suggested. If FOBT were used as the primary screening strategy, current evidence suggests that colonoscopy capacity may be sufficient. However, if FOBT/sigmoidoscopy were the primary screening paradigm, flexible sigmoidoscopy capacity may fall short.

"If colonoscopy were the primary screening strategy, there is substantial uncertainty that current colonoscopy capacity would be sufficient," they wrote. "Some modeling estimates suggest that colonoscopy capacity may be sufficient if screening targets are achieved over a 5- to 10-year period."

Among the primary national guideline-making bodies, the U.S. Preventive Services Task Force (USPSTF) and the American Cancer Society-U.S. Multisociety Task Force (ACS-USMSTF) now include CTC at five-year intervals as a screening option, the authors noted. The Centers for Medicare and Medicaid Services (CMS) rejected population-wide Medicare coverage of screening last May.

"The most important factor related to being screened for colorectal cancer is access to care -- i.e., having insurance coverage, a usual source of care, or both," the NIH panel wrote. In addition, two socioeconomic characteristics -- income and education level -- are important correlates of screening.

And it's not just the presence of coverage, but the quality of insurance coverage that makes a difference because the cost of co-payments and other factors raise important financial considerations for the patient.

"The structure of insurance is highly variable," the authors wrote. "When studying insurance, it would be better to have a more detailed characterization. For example, among persons with Medicare, those with supplemental policies are more likely to be screened."

Promotion at the healthcare system level is also key. "Studies conducted within integrated healthcare systems -- such as [Veterans Affairs (VA)], Kaiser Permanente, and the National Health Service in the U.K. -- have found that organized approaches to screening dramatically increased colorectal cancer screening rates," they wrote.

As for public promotion, more research into socioeconomic, cultural, and geographic factors is needed to determine which strategies would be most effective in motivating patients to participate in screening.

"Current sources of population-based data that are available for monitoring colorectal cancer screening in the U.S. are inadequate for estimating rates and essentially nonexistent for assessing appropriate use," the authors wrote.

Nevertheless, existing research supports the use of integrated screening efforts at the provider level, including "patient reminder systems and one-on-one interactions with providers, educators, or navigators," they wrote.

In addition, other screening program goals should include:

Tailoring specific approaches to match characteristics and preferences of target population groups to increase colorectal cancer screening
Implementing systems to ensure appropriate follow-up of positive colorectal cancer screening results
Eliminating financial barriers to colorectal cancer screening and appropriate follow-up
Developing systems to ensure high quality of colorectal cancer screening programs

By Eric Barnes
Auntminnie.com staff writer
February 4, 2010

JACR editorial: Medicare used double standard in VC decision, September 22, 2009

NEJM editorial lauds CMS rejection of VC, May 28, 2009

CMS rejects Medicare coverage for virtual colonoscopy, May 12, 2009

American Cancer Society recognizes virtual colonoscopy screening benefit, March 5, 2008