USPSTF Draft Recommendation for CRC Screening Comes at Critical Time in Cancer Care, Says Limburg

Colonoscopy is an examination that allows direct visualization of the entire large intestine and also, if necessary, the final part of the small intestine. It is used as a diagnostic test, allows biopsy extraction and endoscopic therapy.
Paul J. Limburg, MD, highlights the significance of the United States Preventive Services Task Force’s draft guidance for colorectal cancer screening.

In response to emerging epidemiological data demonstrating an increase in colorectal (CRC) cancer diagnoses in patients less than 50 years of age, the United States Preventive Services Task Force (USPSTF) has issued a draft recommendation supporting earlier CRC screening. Under the proposed B grade guidance, all adults would be screened for CRC at 45 years rather than 50 years, the current clinical standard.1

The proposed draft guidance is open to public comment until November 23, 2020. When final, it will replace the USPSTF’s 2016 A grade recommendation that CRC screening should be initiated at 50 years and continue until 75 years.

“We have recognized that CRC can be prevented or treated more effectively when caught early, so a greater emphasis on CRC screening for the screening-eligible population is a good thing. There are convincing data that support that the biggest change between the 2016 USPSTF guidelines and the current draft version, beginning screening at 45 years rather than 50 years,” said Paul J. Limburg, MD, a gastroenterologist at Mayo Clinic in Rochester, Minnesota. Limburg also serves as chief medical officer for screening at Exact Sciences, the maker of the stool DNA test Cologuard®. Cologuard was notably included among the USPSTF-recommended CRC screening options in the proposed guidance.

In an interview with Gastroenterology Advisor, Limburg discussed the significance of the draft recommendation and strategies for increasing screening rates.

Gastroenterology Advisor: Please comment on the USPSTF’s draft recommendation.

Dr Limburg: The recommendation to initiate CRC screening at a younger age is a helpful way to try to reverse some of the emerging trends that we’re seeing with respect to a greater number of new and even fatal cases in younger patients. Beginning screening earlier will help to have an impact [in the context of] some of the emerging statistical data.

As was noted in 2016, modeling data supported a favorable impact of screening at 45 [years], but I think the data were less mature at that point than they are now. Moving screening to 45 [years] will allow the nearly 19 million additional people who would be eligible for screening to have greater access to that preventive service, and should help us [work toward] meeting our public health goals.

I do think there is a reliance on modeling data in some of the USPSTF’s and others’ guidelines. We need to understand what the models are actually showing and how that applies to the real-world setting, and some of the modeling data that are generated and considered by the guideline groups are based on assumptions that are not necessarily real-world.

For example, participation with CRC screening is often modeled at 100% participation over a lifetime, which we all know is not clinically realistic or even possible. So, bringing in some of the real-world data around the different testing strategies and seeing how that affects the outcomes of interest that the models would estimate would give a better sense of the different options’ comparative effectiveness.

Gastroenterology Advisor: In 2016, approximately one-third of eligible adults in the United States pursued CRC screening. To what do you attribute this underutilization?

Dr Limburg: I don’t think CRC screening is always at the top of the list for patients and providers. It can be challenging to focus on; there is more than 1 screening option available, and the conversation is sometimes less likely to happen in a busy primary care practice due to time constraints.

We know that groups like the National Colorectal Cancer Roundtable have set a target of 80% screening participation, and based on [their] latest survey data, only about 68% of people are up-to-date with their CRC screening needs, so we have room for improvement.

By endorsing more than 1 option for CRC screening, the USPSTF truly allows patients and clinicians to choose the test that best suits their needs and preferences. An informed decision-making process where patients understand what tests are available and the advantages and limitations of those different strategies, and are then able to pick the option that works best for them is the way to optimize engagement. As the COVID-19–related restrictions have impacted clinical practice at multiple levels, having the opportunity to continue with CRC screening using a home-based option may have particular relevance.

Gastroenterology Advisor: What can health care providers do to drive screening rates?

Dr Limburg: Recognizing that CRC screening is an opportunity for both genders, that the disease can be detected at a pre-cancerous stage, and that the precancerous lesions, adenomatous polyps, or serrated lesions often aren’t associated with any signs or symptoms emphasizes that having the conversation about CRC screening and picking an option that works best for that clinician-patient relationship is critically important and potentially lifesaving.

CRC screening has to start with the test that the patient and provider select, but has to be followed all the way through. The only way to derive benefit from a non-invasive screening is to follow through with colonoscopy if the initial screening test result is positive. Working together across different stakeholder groups, making sure that we consider CRC screening, is something that we need to commit to both from the onset and all the way through to completion.

[Further,] working together to eliminate any barriers, for example, legislative changes that could help allow patients to have the full CRC screening experience without facing cost share, would help us to continue to drive screening patients participant rates up and beyond that 80% target.


Draft recommendation statement; colorectal cancer: screening. US Preventive Services Task Force. October 27, 2020. Accessed November 3, 2020.