Contemplating colorectal cancer screening choices

Invitations to patients eligible for colorectal cancer screening need not be limited to office visits. A 2018 systematic review and meta-analysis of 73 randomized clinical trials of U.S.-based interventions found that mailing fecal tests more than doubled the likelihood that targeted patients received colorectal cancer screening. A recent trial in Clinical Gastroenterology and Hepatology compared screening completion in community health center patients randomly offered one of three options in an outreach mailing: colonoscopy referral only, fecal immunochemical test (FIT) only, or an active choice of colonoscopy or FIT. At 6 months, 12.8% of patients in the active choice arm had completed screening compared with 11.3% in the FIT-only arm and 5.6% in the colonoscopy-only arm.

As I discussed in a previous post, one problem with screening colonoscopy is that it is frequently repeated at shorter intervals than the recommended 10 years without a good reason. In fact, 10 years may not be long enough. A cohort study in JAMA Oncology suggested that a 15-year rescreening interval may be appropriate for average risk patients without a family history of colorectal cancer and with negative findings on their first screening colonoscopy. Using Swedish register-based data sources, researchers showed that individuals meeting these two criteria between 1990 and 2016 had 15-year standardized colorectal cancer incidence and mortality ratios that were lower than the 10-year cumulative risks in a matched control group.

A U.S. cross-sectional study that relied on data from the national Gastrointestinal Quality Improvement Consortium registry found that most patients with an episode of acute diverticulitis were not more likely to have colorectal cancer diagnosed on a follow-up colonoscopy than asymptomatic patients undergoing a screening colonoscopy. Only those with complicated diverticulitis (i.e., diverticulitis with perforation or abscess) were significantly more likely to have colorectal cancer (adjusted odds ratio = 3.57; 95% CI, 1.59 to 8.01).

Regarding the multitarget stool DNA (MT-sDNA) test for colorectal cancer screening, a study of 500 randomly selected patients in a Midwest health system found that about 1 in 5 had the test ordered inappropriately. The most common reasons for inappropriate ordering were having had a colonoscopy within the previous 10 years, having a family history of colorectal cancer, reporting symptoms suggestive of possible colorectal cancer, being younger than 45 years old, and having a previous diagnosis of adenomatous polyps.

A multitarget stool RNA (MT-sRNA) test with performance characteristics similar to those of the MT-sDNA test was approved in May 2024 by the U.S. Food and Drug Administration. Both tests are more sensitive for colorectal cancer and advanced adenomas than FIT but have lower specificity, resulting in higher false positive rates and more diagnostic colonoscopies. Of note, a research letter demonstrated that lowering the threshold for a positive FIT produced similar sensitivities and specificity as the MT-sRNA test, even without the RNA component of the test.

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This post first appeared on the AFP Community Blog.

Canadian mammography kerfuffle echoes U.S. screening debate, 15 years later

In November 2009, I was a medical officer with the U.S. Preventive Services Task Force (USPSTF) at the Agency for Healthcare Research and Quality. The health reform legislation that would eventually become law as the Affordable Care Act (or "Obamacare" after then-president Obama) was being fiercely debated in Congress. Politicians who opposed expanding health insurance to the poor, self-employed, and employees of small businesses launched all sorts of spurious charges, the worst being that the law would establish "death panels" that would determine whether elderly patients with chronic medical conditions would be allowed to live or die. Into this political maelstrom stepped the USPSTF, releasing an ill-timed update that recommended against routinely screening women aged 40-49 for breast cancer. Contrary to popular belief, this language didn't mean they were advising all women in this age group NOT to be screened; instead, they were empowering patients to make this decision individually in consultation with their physicians, based on their preferences and values.

The current Task Force looked at essentially the same evidence and come to a different conclusion: start screening everybody at age 40, never mind the potential harms. In a Medscape commentary, I explained why I don't believe this change is justified. However, it put a great deal of pressure on our neighbors to the north and the Canadian Task Force on Preventive Health Care to reassess its recommendations and come to a similar conclusion. If Americans are getting screened for breast cancer in their 40s, why shouldn't Canadians too?

The Canadian Task Force released its draft recommendations two weeks ago. In short, they echo the USPSTF's recommendations in 2009 and 2016 and maintain that breast cancer screening should be a "personal choice," particularly for females younger than age 50. "For women aged 40 to 49, based on the current evidence (trials, observational studies, modelling and a review on values and preferences), we suggest not to systematically screen with mammography [emphasis mine]. Because individual values and preferences may differ, those who want to be screened after being informed of the benefits and harms should be offered screening every 2 to 3 years." The supporting data, much of it derived from systematic reviews, is extensive and compelling, including discussion tools for women in various age groups.

Unlike the U.S. 15 years ago, Canada isn't in the midst of a major health reform debate - they've already had an equitable universal health care system for decades, thank you very much. But that hasn't stopped one health official from trying to score cheap political points. The Canadian Minister of Health, Mark Holland, a lifelong politician without any health professions training, has forcefully objected to the CTFPHC's draft recommendations and ordered an unprecedented "external review" that will, no doubt, include conflicted experts such as radiologists who have obvious financial incentives to perform as many mammograms on asymptomatic women as possible.

Here is Holland being interviewed on an Ottawa news channel. When the anchor asks him what he would do if the external review confirms the Task Force's recommendations, he dodges and weaves and avoids answering.

As a former USPSTF member once said, "we can follow the evidence wherever it leads," or we can start with a preordained conclusion and cherry-pick data that supports what we already know to be true. Canada, Mark Holland, and the CTFPHC would do well not to mimic the most expensive, inequitable health care system in the world and associate higher percentages of women receiving mammography in their 40s with better preventive care "quality."

Why medications for AUD should be as popular as GLP-1 agonists for obesity

A recent commentary in the Journal of General Internal Medicine compared anti-obesity medications with medications for alcohol use disorder (AUD). Both chronic conditions are “characterized by behavioral patterns that pose risks of adverse health consequences” and “subject to societal stigma including … the idea that they reflect a lack of personal willpower.” While prescriptions for costly glucagon-like-peptide-1 (GLP-1) agonists for obesity such as semaglutide have skyrocketed, use of less expensive drugs for AUD remains low. The authors suggested that public perceptions that the latter are ineffective or unnecessary, implicit biases of clinicians, and delayed health benefits of alcohol cessation compared to weight loss contribute to the differences in use.

Given the magnitude of the problem, which worsened during the pandemic, an American College of Physicians policy brief advocated “training, payment, and delivery system policies to enable physicians and other qualified health professionals to screen, diagnose, and treat excessive alcohol use and AUD.” Recognizing patients with excessive alcohol use remains a challenge despite a U.S. Preventive Task Force recommendation to routinely screen adults, including pregnant patients, for unhealthy alcohol use and provide brief behavioral counseling interventions to persons engaged in risky or hazardous drinking.

A systematic review in JAMA’s Rational Clinical Examination series concluded that the Alcohol Use Disorders Identification Test (AUDIT) is most the useful tool for identifying AUD in adults and postpartum individuals, while the abbreviated AUDIT-Consumption (AUDIT-C) best identifies excessive alcohol use in children aged 9 to 18 years and older adults. Other studies have found that a single question alcohol screen (“How many times in the past year have you had five (men)/four (women) or more drinks in a day?”) is comparable to the AUDIT-C in detecting unhealthy alcohol use and current AUD in primary care.

Articles in the January 2024 and May 2024 issues of American Family Physician discussed FDA-approved and off-label pharmacotherapies for adults with AUD. According to an Agency for Healthcare Research and Quality review, oral naltrexone, acamprosate, and topiramate have the strongest evidence for reducing alcohol consumption, while injectable naltrexone, baclofen, and gabapentin have weaker supporting evidence. Of the two first-line treatments approved by the FDA for AUD, acamprosate is contraindicated in patients with a creatinine clearance of ≤ 30 mL/min, while naltrexone should be avoided in patients who use opioids or have advanced liver disease. Disulfiram is not more effective than placebo in reducing alcohol consumption.

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This post first appeared on the AFP Community Blog.