Cologuard – Cancer Screening Technology, with Dr. Paul Limburg

Episode Transcript

Ariel: Hello everybody, and welcome back to “The Colon Health Podcast.” This is your co-host Ariel Bridges, and I am so excited because we have a very special guest today. He’s a professor of medicine. He’s the chief medical officer for screening at Exact Sciences. He’s a principal investigator for the Cancer Prevention Network. He’s won tons of awesome awards like a Cancer Prevention Laurel, for dedication to community programs for the Cancer Research and Prevention Foundation of America, a career development award from the National Cancer Institute. Ladies and gentlemen, Dr. Paul Limburg. Hi, Dr. Limburg. How are you?

Dr. Limburg: Hi, Ariel. I’m great. Thank you for that very nice introduction. Pleasure to be with you today.

Ariel: Oh my goodness. Thank you so much for being here. One of the things that we really wanna talk about is Cologuard. And for those of you that aren’t familiar Cologuard is intended to screen adults 45 years of age and older, who are at average risk for colorectal cancer by detecting certain DNA markers and blood in the stool. So just to get started, Dr. Limburg, can you kind of share the story of Cologuard’s development and the growth of Exact Science as the company that you are the chief medical officer for?

Dr. Limburg: Yeah, I can Ariel, thanks for that intro. That was a great overview of Cologuard. Maybe just to take a step back and to put it into context, a little bit of information about colorectal cancer screening and the public health burden that this disease incurs. So we know that colorectal cancer is the third most common time type of cancer in the United States, and the second leading cause of cancer deaths. There are studies that have demonstrated the effectiveness of colorectal cancer screening, finding colorectal cancers earlier when they are more treatable or even finding pre-cancerous polyps so that they can be removed and never become cancer. But unfortunately, with respect to average risk screening, we still do not have enough participation from the population to reach our targets, where we have thought that we could do more and truly make a difference in reducing the burden of this all too common disease. So colorectal cancer screening participation is about 67%, maybe 68%, but somewhere in the range of a third of patients who should be screened are not being regularly screened or up to date with the endorsed options. There are also studies that have shown that it’s not one size fits all, different tests or screening options have worked better for different patients. So having an array of options or a choice of options can increase participation. So that was really the framework for developing the Cologuard assay, which as you mentioned, is a stool test that looks for molecular markers and blood that may be associated with colorectal cancer or pre-cancers

Ariel: Awesome. And thank you so much for providing that background. We’ve had some other podcast episodes where we’ve discussed the importance of getting tested and how colon cancer is one of those cancers that is uniquely preventable. And something that really stuck with me that you touched on was having a choice of op options for getting screened so we can increase access. I think a lot of people don’t realize that they actually do have different options. So it’s great that you’re here to shed some of those different options that people have. So you’ve shared a little bit about the practicalities of Cologuard. Can you just dive into a little bit more detail about how it works, how much costs, and how people can get access to this test?

Dr. Limburg: Sure. So Cologuard or multi target stool DNA is another name for the test, is endorsed by major guidelines like United States Prevented Services Task Force, American Cancer Society, the U.S. Multi-Society Task Force, others. And really, it is a home-based option where it’s available through prescription only. Prescription can be obtained from a patient’s primary care provider, can also be obtained through telehealth options Now that we’ve moved to telehealth for lots of our different healthcare needs in the current situation with COVID and post-COVID restrictions on some of our access to onsite facilities. So the home-based Cologuard option after the prescription is provided, the test is ordered, the test can be shipped directly to a person’s home. The sample can be then collected at home returned through express shipping. There is a customer report service that is available 24 hours a day, 7 days a week, 365 days a year in over 240 languages to help address any questions that patients or their providers might have throughout that collection process. Once the sample is returned to the Exact Sciences laboratory takes about two weeks for the result to become available. That result is given to the patient’s provider who ordered the test. And then the follow-up is managed with that provider.

Ariel: Wow. So overall it’s actually, if all things considered, a fairly quick process, if you decided to kind of take this on and do it at home.

Dr. Limburg: It really is. And the test and the process were designed with the user experience in mind, if you will, to try to overcome any barriers to screening participation that patients might perceive based on difficulty with the process. And I think even more so now, having a home-based option makes a whole lot of sense, so that patients who are ready to undergo average risk colorectal cancer screening can meet their needs with a test that truly is delivered to their home and can be returned in a simple, straightforward way.

Ariel: And I love too that it really helps. I feel like a lot of people, there’s a lot of stigma around colonoscopies and getting tested and just things surrounding colon health in general. So it’s great that for people that are maybe a little insecure or worried about those types of perceptions, they can just take care of this at home, in the privacy of their home. I think that’s a great way to extend options like you mentioned earlier and make sure that things are available to a wider range of our population.

Dr. Limburg: It’s important that we recognize that different patients may choose different options, Aerial. And for patients who do undergo Cologuard screening, if the test result is positive, then they should undergo a follow-up colonoscopy. So working closely between primary care and gastroenterology, you know, the test results…positive Cologuard result does need to have that follow up colonoscopy. A negative Cologuard result, most guidelines would repeating that screening test or another screening test at about three years.

Ariel: Awesome. Yes, that’s so important to highlight the follow-up steps necessary. So Cologuard has been released, or since Cologuard has been introduced into the medical world, how would you say that the medical profession has reacted?

Dr. Limburg: I think it’s been seen as another positive option for patients and providers who prefer the characteristics of the Cologuard test. It’s a very accurate test. The sensitivity from a large, nearly 10,000-person study that led to FDA approval for Cologuard, the sensitivity for cancers was 92%. So it’s an accurate, accessible test. To date since the Cologuard was approved in August of 2014, more than 6 million people have been screened with the test.

Ariel: Wow, that’s a lot of people. And of those people, do you know how many were positive?

Dr. Limburg: It’s a great question. We don’t have those data. Exact Sciences laboratories does not have access to all of the follow-up colonoscopy information, but in the study that led to the FDA approval, about 16% of Cologuard tests would be expected to be positive. And then for those that undergo follow-up colonoscopy, the data would be available to show how many had cancers, pre-cancerous, or other findings.

Ariel: And you were touching on this a little bit earlier about how COVID has affected all of our healthcare access in the way that we’re approaching healthcare these days. How have you seen it affect cancer screenings in general, and how did you see it affect Cologuard orders in particular?

Dr. Limburg: Yeah. Great question. So I think we would all remember that just over a year ago, during the initial phases of the pandemic, really participation in lots of healthcare opportunities, preventive services in particular declined dramatically. And Ned Sharpless who was the director of the U.S. National Cancer Institute has commented that by his estimate, nearly 10,000 excess deaths from colon and breast cancers over the next decade are projected because of those declines in participation with different screening opportunities. So I think we are just now starting to see some rich turn towards numbers that are more consistent with the trends we were seeing prior to the pandemic. We still haven’t caught up completely, but I do think that with the new norm, if there is one, people do have access to meet their colorectal cancer screening needs in multiple different ways. So my encouragements would be that people should you aware of what’s available in their community, find an option that works best for them, and then work with their clinicians to make sure that they can get the test ordered that will work best for them.

Ariel: Yes, we are all about that access, being informed about your different options, especially in light of how things have changed and may have…will continue to change as we continue to navigate this pandemic. I still am thinking about how many people have been able to utilize Cologuard since it’s been created. And you were touching on how it’s effective that’s you said I believe in 92% detection rate, is that right?

Dr. Limburg Sensitivity. Yep, exactly.

Ariel: And how do you imagine this sort of thing changing the medical industry’s approach to colorectal cancer screening moving forward?

Dr. Limburg: Well, recognizing that over 50,000 people per year are dying from what should be in large part a preventable disease is really a mission that everyone can work on together. So trying to make sure that there’s enough education out there for patients and individuals to recognize when they should be screened for colorectal cancer, what their risk factors are, what the options are, what the follow through should be, all of that is extremely important. And we all need to work together to make sure that we can get that critical information out through multiple different communication channels, including this podcast. So thank you for that. I do think that being able to, again, appreciate that colorectal cancer screening is available and it’s important, even if somebody doesn’t have symptoms, starting now at age 45, if somebody doesn’t have other colorectal cancer risk factors is endorsed by major guideline groups and really should be a goal that we set for all of our patients, family members, community members, as healthcare providers.

Ariel: Yes, I am particularly passionate about educating people about their options and just the state of their health in general, so they can better advocate for themselves and their needs. I feel like a lot of people get caught up in feeling like they’re forced to move in a particular direction or that they only have certain options, but it’s things like Cologuard that have people realize that there are different options for them and things that they can do that make them feel more comfortable and are better suited for them and their needs. This is awesome and really promising. A step in the right direction, like you said, in joining together and making this our mission of decreasing something that should be and can be preventable. Or I’m curious to hear what you think some of the largest changes to medicine and lab techniques will be, or that we can expect to see over the next 5 to 10 years. Seeing Cologuard and everything that it’s done so far is makes me at least very optimistic about the future. I’d love to hear some of your thoughts on what we might be able to expect soon.

Dr. Limburg: You know, medicine is always in a state of evolution, Ariel, and with the molecular tools and technologies and understanding of disease processes that are occurring every day, I do see the, the landscape continuing to change in a positive way. Starting with Cologuard, there’s a next generation Cologuard test that is currently being evaluated with a goal of improving performance and making an even better test available to patients and providers. Beyond that, the idea of using a blood sample to screen for colorectal cancer, or maybe even multiple cancers from a single specimen is also being actively pursued by different groups, Exact Sciences included. So I think it’s gonna be an exciting time over the next couple of years here. And I do think that being able to detect disease early, intervene more effectively hopefully will result in fewer people, fewer families being impacted by colorectal and other cancers.

Ariel: Wow. So the potential for you’re showing up for your annual physical, you’re getting your routine blood work, and just a panel to check out different cancers. Is that kind of along the lines of what you’re describing?

Dr. Limburg: It is. And I think the technology looks very promising. There are still some big questions about how would that test be applied. When would we start screening with a blood sample? How often would we need to repeat the test? How cost effective would it be? What would we do with positive results and negative follow-up test results? So there’s a lot of questions that need to be addressed, but I’m optimistic that the future of cancer screening will continue to look different than it does today and the outcomes will continue to improve as well.

Ariel: I think that is incredibly encouraging. Wow. That’s very exciting. So we are just about finishing up. You shared such helpful and exciting information today. Is there any parting information or words that you’d like to share with our listeners about Cologuard or anything else surrounding colon cancer and colon health?

Dr. Limburg: I would just say, Ariel, that the bottom line is colorectal cancer screening works. There are multiple test options that are available even now with the changes that we’re all facing with respect to the pandemic. But find an option that works that is available and that a patient is willing to complete so that we can make sure that we don’t incur a second wave of preventable disease resulting from the changes, the disruption in clinical practice that we’re all facing today.

Ariel: Excellent. Dr. Limburg, thank you so much for being here. We so appreciate it.

Dr. Limburg: Ariel, it was my pleasure.