A world without colonoscopy? 10 gastroenterologists weigh in on the future of GI's top procedure

Colonoscopy has been the bread-and-butter procedure of the GI field for decades, but new technology continues to roll out. Ten GI physicians consider whether or not a new device will ever be able to replace this staple of the gastroenterology field.

Ask a Gastroenterologist is a weekly series of questions posed to GI physicians around the country on business and clinical issues affecting the field of gastroenterology. We invite all gastroenterologists to submit responses. Next week's question: What qualities do gastroenterologists look for in potential physician practice and endoscopy center partners?

Please submit responses to Carrie Pallardy at cpallardy@beckershealthcare.com by Thursday, Sept. 4, at 5 p.m. CST.

Question: Do you think that a new technology will ever be able to replace colonoscopy?

Dr. GarzaAna Garza, MD, Colorectal Institute, Dignity Health Glendale (Calif.) Memorial Hospital and Health Center: This is a complicated question. From a diagnostic perspective, alternatives such as barium enema and CT colonography have similar diagnostic capabilities. CT colonography will have an advantage if it can be done without bowel preparation.  Capsule endoscopy is an emerging technology, which should have similar diagnostic capabilities to colonoscopy. There may be non-imaging techniques such as stool genetic analysis that will help define polyps and cancers, but probably will not help much with mucosal disease such as ulcerative colitis.

Therapeutically, the colonoscope is unique in its ability to biopsy and even remove abnormalities in the colon. I am not aware of any robots or other technology which is competitive with colonoscopy.

Combined, the unique diagnostic and therapeutic capabilities of the colonoscope make it difficult to replace. There is increasing attention to the costs of these various technologies and the costs of colonoscopy will be difficult to beat, particularly for therapeutic functions. In summary, it is possible that new technology will have niche applications to replace colonoscopy, but nothing is on the horizon to replace the overall diagnostic and therapeutic capabilities.

Darrell M. Gray, II, MD, MPH, Director, Community Engagement & Equity in Digestive Health, Division of Gastroenterology, Hepatology, and Nutrition, Division of Cancer Prevention and Control, The Ohio State University Wexner Medical Center (Columbus): Over the past four decades, there have been momentous technological Dr. Darrell Grayadvances in the field of gastroenterology. Specifically in the domain of colorectal cancer screening and diagnosis, we have witnessed the evolution from the era of the rigid sigmoidoscope to a recently FDA-approved noninvasive test that analyzes stool DNA and blood biomarkers to detect the presence of precancerous polyps and cancer. Additionally, patients, providers and payers alike now have a stake in the choice of the screening tool(s) used, of which colonoscopy is the gold standard for being able to both detect and remove precancerous lesions.

However, the best test for colorectal cancer screening is the one to which the patient will comply and that will be completed safely and appropriately. Think about it this way. What good is a colonoscopy if a patient refuses to have it? On the other hand, what good is stool-based testing if a patient doesn't have it performed at a guideline-based interval and/or doesn't have a colonoscopy in follow-up to a positive test result?

I believe that the technology that we use for colorectal cancer screening will continue to evolve, particularly as the demand for less invasive, less expensive and less time-consuming methods increase and our aging population continues to grow. However, I also believe that colonoscopy is here to stay. It will be challenging to replace colonoscopy with a technology that can both detect and remove precancerous lesions during one procedure.  

William Katkov, MD, Providence Saint John's Health Center, Santa Monica, Calif.:Colonoscopy remains the most effective method for the screening and prevention of colon cancer. Dr. KatkovThe goal is to screen as many individuals as possible in the population at risk for colonic neoplasia and malignancy. Noninvasive screening tools are unlikely to replace colonoscopy. In fact, as the screened population expands, the volume of colonoscopy is likely to increase. In some cases, colonoscopy will become a diagnostic rather than a screening tool when it is employed to follow-up a positive non-invasive test.

Dr. David LiebermanDavid A. Lieberman, MD, AGAF, AGA Institute Clinical Research Councillor, Professor of Medicine; Chief, Division of Gastroenterology and Hepatology, Oregon Health and Science University (Portland):  I would suggest that the question might be framed differently:  is it possible that a new technology will change the role of colonoscopy?

Colonoscopy will remain the primary tool for evaluation of higher risk patients — those with a family history of colorectal cancer, past history of polyps or cancer and with lower GI symptoms. In addition, colonoscopy is the primary tool for evaluation of other positive screening tests. It is hard to imagine a biomarker test or imaging that will provide the accuracy and ability to deal with pathology, which is provided by colonoscopy.
 
Colonoscopy is now used commonly for CRC screening of average-risk asymptomatic individuals. Studies show that colonoscopy accounts for about 80 percent of CRC screening in the United States. The test appeals to both patients and primary care providers because of the potential for early cancer detection, but also cancer prevention by detection and removal of precancerous polyps. In addition, studies show that the risk of serious colon neoplasia is low for 10 years after a high-quality negative exam, so it does not need to be repeated often.  

The role of colonoscopy as a primary screening test could evolve with new technology. If a new, less invasive test could achieve the goals of colonoscopy — namely high levels of early cancer and polyp detection — such a test could replace colonoscopy as a primary screening test. Colonoscopy would still be needed to evaluate positive screening tests with other modalities. Current stool-based tests achieve good cancer detection, but fail to detect most patients with advanced polyps. Current imaging tests can detect both cancer and polyps, but is costly, require bowel prep, and if polyps are seen, colonoscopy is recommended, with a second bowel prep. Serum tests to detect molecular markers of risk have not achieved high rates of cancer or polyp detection.  A future non-invasive test, which can achieve high rates of early cancer detection plus detection of advanced polyps, could change the role of colonoscopy in colorectal cancer screening.  

Scott McKnight, MD, colorectal surgeon, Memorial Hermann Sugar Land (Texas): At some point, supply will meet demand. There is no doubt that a less invasive means to screen, survey, and treat the large intestine and rectum is needed. Patients would certainly appreciate it. Imaging modalities currently used approach the sensitivity of colonoscopy for diagnostic purposes. The problem is that to remove a polyp, stop bleeding, or obtain a biopsy, one must traverse to bowel to reach the point of interest. I don't see a less invasive way around this. Perhaps endoscopes will become more easily maneuvered and more precise. Otherwise, I don't see a replacement for the therapeutic benefit of endoscopy.

Manoj K. Mehta, MD, AGAF, Gastroenterology Consultants of the North Shore, SC (Kenilworth, Ill.): The way technologies take root in our society is a complex process. Sometimes, the best technologies don't win. Think BetaMax vs. VHS (or BlueRay vs. DVD if you're younger). Sometimes, technologies are just not in the right place at the right time. WebTV failed in the Dr. Mehta90s but now every new TV is an internet-based "smart TV." Sometimes we just get used to existing means of doing things and are resistant to new ideas no matter how much better they are. Think metric vs. imperial. Lastly, don't forget the impact of economics. Where's the economic incentive to change to metric?

It seems to me the new ideas that succeed best seem to either fill a completely new niche or so radically alter our way of doing things that the tradeoff is acceptable. Examples of new-niche technology include the idea of text messaging and the internet, technologies even their own inventors did not foresee being used as they are. As far as reinventing existing technologies, the iPad was hardly the first tablet. Yet it reigns supreme.

If there was any procedure that could use a radical reinvention, it would be colonoscopy. So, the field is ripe for change. But, in what ways could it change? Could we screen the colon in a different way altogether, such as "virtual colonoscopy”", capsule, or fecal DNA? Some ideas are more promising than others. If we could know which polyps were important, we could ignore many of them. Yes, there have been progresses in that area, including high-resolution fluorescence and confocal endoscopy. Can we use chemoprevention to arrest polyp transformation? Well, we might slow it down but so far it's not enough.

Ultimately, if people have colon polyps, and the progression to cancer cannot be predicted or avoided, somehow we need to go in there and get them out. While there might be new developments in robotics, remote control devices, nanobots, etc., I believe that the existing culture of screening and therapeutic colonoscopy will not change as radically as everyone thinks. There is a vast infrastructure designed around the current system, and despite their being economic pressures to change, there will be even more economic pressures not to. Finally, people have accepted colonoscopy, they deal with the hassles, they often demand it when it is not indicated, they even brag about getting it done instead of it being taboo. As I said, the best ideas don't always win.

So is there a holy grail in colonoscopy? Is there a radical reinvention ready to happen that will change the way we do business? Yes. That missing piece of the puzzle is bowel prep. You know this because each of your patients tells you the same thing: "The procedure was easy, but doctor that prep!" This is the area I foresee radically changing the landscape of colonoscopy, not so much in what we do but how we accomplish it. I think colonoscopy is here to stay. What we need is not virtual colonoscopy. What we need is virtual bowel prep.

Karen Simon, MD, Ventura County Gastroenterology (Camarillo, Calif.): Colorectal cancer is often considered the most preventable, yet least prevented cancer in the United States,Dr. Karen Simon largely due to lack of compliance with regular screening. This is unfortunate because when it comes to colon cancer screening, we have the rare opportunity to actually prevent cancer from ever forming. However, this only works when patients are getting screened regularly. Colonoscopy is the gold standard when it comes to screening, however we know the prep and procedure involved can stand in the way of people getting screened regularly and diagnosed when cancer or pre-cancer is most treatable or preventable. And still, there is a subset of patients who cannot undergo colonoscopy.  

While colonoscopy is always offered as an option, I firmly believe the best test is the one that gets done. Other less invasive or non-invasive screening methods are available for patients who cannot or simply will not undergo colonoscopy.  A new FDA-approved test, Cologuard, looks for both altered DNA and blood biomarkers associated with colorectal cancer and pre-cancer in the stool. Cologuard is an exciting new option available by prescription through a physician and does not require the same dietary restriction or bowel prep associated with colonoscopy and other more invasive screening methods. The patient can take the test in the privacy of their own home and mail their sample back to the lab for testing. If the test yields a positive result, a follow-up colonoscopy is recommended. While not a replacement for colonoscopy, Cologuard serves as another tool for clinicians to offer patients, in an effort to get them screened.

Patrick TakahashiPatrick Takahashi, MD, CMIO and Chief of Gastroenterology Section of St. Vincent Medical Center (Los Angeles): The medical field has seen a tremendous metamorphosis during the latter parts of the 20th century as well as this 21st century. Although colonoscopy has been the gold standard for both diagnostic and therapeutic purposes, I would not be surprised if it will be supplanted with a new technology in the near future.  

Already, there have been improvements radiographically with the advent of virtual colonoscopy. However, this technology is mainly encumbered by an inability to perform any sort of therapeutic procedures within the colon.  Hence, the technology is really limited to a smaller subset of patients, i.e. the elderly or those patients who decline a standard colonoscopy due to risks related to sedation, co-morbidities, advanced age, etc.  

What will replace colonoscopy?  That is anybody's guess. Perhaps a remotely controlled device which can transmit images via Bluetooth or an analogous technology will present itself on the horizon of gastroenterology! Although there is a tremendous amount of technological power within a current colonoscopy, the controls of the device are still rather rudimentary and crude, without significant ergonomic improvements within the past few decades. I for one am looking forward to the next set of advances in the world of gastroenterology.  

Dr. VashiPankaj Vashi, MD, Lead National Medical Director, National Clinical Director of Gastroenterology/Nutrition, Metabolic Support and Gastroenterology, Cancer Treatment Centers of America at Midwestern Regional Medical Center (Zion, Ill.): As new and improved technologies are introduced and procedures evolve, it is our responsibility as medical practitioners and advocates for our patients to determine if they are appropriate and justified. I make it a point to stay well-informed of what's happening in and around the GI field for that very reason. Until something else is proven more effective, colonoscopy remains the gold standard for diagnosis of colorectal cancer in 2014. Recent FDA approval of stool DNA testing, which is extremely sensitive in detecting colon cancers, is another tool we can use; however, they will not replace the colonoscopy. Research supports that the colorectal cancer screening performed with colonoscopy is responsible for dramatic reduction in deaths from that cancer. It also identifies cancers in early stages potentially leading to more favorable outcomes. The other evolving screening tool is CT colonography (CTC). This type of screening is very sensitive and specific, but again patients with abnormal findings will eventually need colonoscopy to biopsy or therapeutic removal of polyps.

Dr. Zelner Richard Zelner, MD, Orange Coast Memorial Medical Center, Fountain Valley, Calif.: Currently, a colonoscope remains the gold standard for both diagnosis and therapy of the colon. There are no other cost effective modalities on the horizon that will take the place of colonoscopy for diagnostic biopsies and therapeutic intervention.

The role of colonoscopy for colorectal cancer screening may become more selective as less invasive modalities become more readily available and cost effective. Cologuard, recently released as an adjunct for colorectal cancer screening, capsule colonoscopy and virtual colonoscopy may all diminish the need for standard colonoscopy in selected individuals.
 
More articles on gastroenterology:
What is the optimal bowel preparation for colonoscopy?
5 things to know about colonoscopy payment: AGA bundle vs. Medicare model
Mayo Clinic to be first to offer Cologuard

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