Patients want convenience, but at what cost?
Dr. Wilson: Dr. Lin, how are your patients in your family practice handling this study? Have conversations changed around colon cancer screening? What are people asking about these days?
Dr. Lin: I don’t think the conversations have changed in my practice that much. When patients ask about this study, we do discuss the limitations, that it wasn’t designed to assess the maximum benefit of getting a colonoscopy because the majority of people assigned to that group didn’t get colonoscopy.
But I think it is an opportunity in primary care to consider the way we present the options to patients. Because I would guess that a majority of primary care physicians, when they present the options, would say colonoscopy is the gold standard and recommend their patients get it. And they only offer fecal testing to patients who don’t want the colonoscopy or really refuse.
That hasn’t been my practice. I’m usually more agnostic, because there are both harms and benefits. If you get a fecal test, the chance of you having a complication from colonoscopy is automatically lower because most of those people will not get colonoscopy. Now obviously, the complications with colonoscopy are pretty rare and usually self-limited, but they do exist. If you’re doing lots and lots of these, eventually you’ll see them. Probably all primary care physicians have patients who’ve had a complication from colonoscopy and may or may not have regretted it depending on how information was presented.
But I feel like this study reinforces my feeling that we ought to be presenting these, and not saying one is superior or inferior to the other. Instead, I’d base it on what the patient’s priorities are. But I feel like this study reinforces my feeling that we ought to be presenting these, and not saying one is superior or inferior to the other. Instead, I’d base it on what the patient’s priorities are. Is your priority finding every single cancer? Do you want to know exactly what the benefit is? I think with colonoscopy, we’re still trying to figure out exactly what the benefit is. Whereas we can say it pretty confidently for fecal tests because we have those randomized trials.
Dr. Wilson: Dr. Johnson, I think patients who are watching need to know, first of all, that if they do the fecal test route, a positive fecal test does lead to colonoscopy. In some sense, all roads lead to colonoscopy once you have a positive screening test. So, I can certainly see the value of just sort of skipping to that point. But what about this risk-versus-benefit relationship? Colonoscopy, albeit a relatively safe procedure, is still a procedure. There is some risk associated with it. If we can get the same benefit from yearly fecal immunochemical testing, is that a better choice potentially, at least for patients at average risk?
Dr. Johnson: The stool-based testing is really more effective for detection of cancer. That’s not screening, where the entire goal is the prevention of cancer. The fecal-based testing, including the stool-based DNA testing, misses the majority of precancerous polyps. And the fecal immunochemical tests, which Dr. Lin just mentioned, misses virtually all of them. We really want to get to the prevention of cancer, meaning identification and removal of polyps, not just screening for cancer.
Dr. Wilson: Do you see anything on the horizon that could unseat colonoscopy as, to quote Dr. Lin, the potential gold standard for screening for colon cancer?
Dr. Johnson: I think not on the horizon for identification and removal of polyps. That’s really the gold standard. Technology continues to advance. We’ll see what happens. But on the short and intermediate horizon, colonoscopy is going to be needed.
We are finding that some patients are starting to acquiesce to stool-based testing because they can do it at home. Maybe they don’t have to do a prep. We’re talking about screening only here, not about the follow-up of patients who have a family history, patients who have colitis, patients who have had colon polyps, or other reasons. Stool-based testing is not an option for the follow-up of those patients.
Convenience testing, in the face of COVID, also has thrown a wrench into things. Patients may have wanted to stay home and do these tests. Again, we need to be proactive, not reactive. We want to prevent cancer, not detect it.
Changing advice in the face of younger screening thresholds
Dr. Wilson: Dr. Lin, I’m 42 years old. I don’t believe I’m at any increased risk of colon cancer based on my family history or other risk factors. I’m 3 years away from when the U.S. Preventive Services Task Force tells me I should potentially consider starting to screen for colon cancer. That recommendation has recently been moved down from 50 years old to 45 years old. So, it’s on my mind as I approach that age. What do you advise younger patients approaching 45 right now in terms of screening for colon cancer?
Dr. Lin: For patients with the risk factors that Dr. Johnson mentioned, I would recommend screening colonoscopy as the initial test.
Assuming you don’t have those risk factors, I present it as we have a couple of different fecal tests. There’s the traditional one that just looks for blood. Then there’s the newer one that also adds DNA, which is more sensitive for colorectal cancer, but a little less specific, which is a problem just because there are more false positives.
But you need to compare that with colonoscopy, which you only need to get done ideally every 10 years if there are no findings. That is more complete. And theoretically, as we’ve been talking about, it would also prevent as well as detect early cancers.
So, I think it’s really down to your preference in terms of how the various factors that come into play, such as convenience of the test and your level of concern about cancer. I do tell patients that family history of cancer is not terribly predictive of whether you get it or not. A lot of people unfortunately who develop colorectal cancer have no previous family history. Diet will come into play to some extent. There are some things that point to increased risk for colorectal cancer if you have a diet high in red meat and things like that. But ultimately, it really is up to the patient. I lay out the options, and whatever they choose, I’m happy to pursue.
But the most important thing is that they do some test, because doing no test is not going to help anyone. I do agree with the notion that the best test is the test that gets done.
Dr. Wilson: Absolutely. I think the NEJM study supports that, even when we’re talking about colonoscopy.
Dr. Johnson, you’ve had some criticisms about the NEJM study, and I think they make sense. At the same time, as this is the first randomized trial of colonoscopy, it’s kind of the only data we have. Are we going to get better data? Are there other studies going on out there that might help shed some light on what’s turning out to be a complicated issue?
Dr. Johnson: Yes, there are ongoing studies. They’re not taking place within the United States, because you couldn’t get through a no-screening option trial. There are comparative studies that are probably still 5 years away looking at stool-based testing.
But again, we have to recognize that if you do these alternative tests that were eloquently discussed by Dr. Lin, and not the colonoscopy, which would be every 10 years with high-quality performance, that you have to annualize or do them in sequence. It’s important that you follow up on those with regularity. It’s not just a one-time test every 10 years for these individual tests.
And any of the time that those tests are ordered, the patient should be instructed that if it’s positive you need a colonoscopy. We’re seeing a lot of slippage on that front for the stool-based testing. Convenience is not the answer. It’s getting the job done.
Dr. Wilson: Would you agree, Dr. Johnson, that for patients that really don’t want to do the colonoscopy for one reason or another, and you’ve done your best in explaining what you think the risks and benefits are, that you’d rather have them get something than nothing?
Dr. Johnson: Absolutely. It comes down to what I recommend and then what you decide. But I still make the point explicit: If we’ve gone through those checkpoints and it’s positive, we agree that you understand that colonoscopy is the next step.