Current Treatment Options for Recurrent Colorectal Cancer

Podcast Transcript

Scott Steele: Butts and Guts, A Cleveland Clinic podcast, exploring your digestive and surgical health from end-to-end.

Hi again everyone, and welcome to another episode of Butts and Guts. I'm your host, Scott Steele, the president of Maine campus and colorectal surgeon, and we're very pleased to have one of the newest members of our colorectal surgery department, Dr. Haniee Chung, who is joining us here as a cancer expert and colorectal surgeon here at the Cleveland Clinic. Dr. Chung, welcome to Butts and Guts.

Dr. Haniee Chung: Thank you so much for having me.

Scott Steele: So for those of our longtime listeners, they know we always like to start out a little bit about your background. So can you tell us where you're from, where'd you train, and how did you come to the point that you're here at the Cleveland Clinic?

Dr. Haniee Chung: Yeah, I am, well, originally from Korea. I'm a third culture kid. I grew up in Korea, moved around a bit, lived in Singapore, the Midwest. Most of my training was in Wash U and St. Louis in the Midwest. And then I took my first job out on the East Coast at Hopkins where that was a unique opportunity to establish a rectal cancer practice, which exposed me to really challenging cases of aggressive and recurring cancer cases. And that kind of put me in touch with folks here at Cleveland and I have good friends here who I trained with, and that's what brings me here.

Scott Steele: Well, we're so excited and lucky to have you here. And so today we're going to talk a little bit about the treatment for recurrent colorectal cancer. So before we dive into that, for those of you haven't listened to prior episodes, Dr. Chung, can you give us a little bit of an overview of colorectal cancer in general?

Dr. Haniee Chung: Well, very technically speaking, colon cancer and rectal cancer is classified separately for more nuanced discussion of staging and treatment. But in general, cancers of the lower GI tract are still common. The fourth most common cancer in the US and the second most common cause of cancer deaths. The vast majority of colorectal cancers develop from polyps, which are benign growths in the lining of the GI tract. When it's caught early and removed, the risk for progression to cancer is significantly reduced.

What's interesting about colorectal cancer trends is that with the advent of screening for colon cancer in the eighties, there's been a steady decrease in the incidence, but the age of patients being diagnosed with colorectal cancer is getting younger. The median age of colorectal cancer diagnosis in 2000 was 72. Now, it's 66. And what's most alarming is that patients who are under 40 are seeing the biggest increases in diagnosis of colorectal cancer, and these patients also tend to present with more aggressive cancers.

Scott Steele: So you brought up a really good point there that the colon and the rectum, although I always tell my patients we're one long garden hose from our mouth all the way to the bottom, colon and rectal cancers are different. But in general, can you give us a scope in terms of how much colorectal cancer in general or colon cancer, rectal cancer leads to recurrence?

Dr. Haniee Chung: Yeah, overall, about 30 to 40% of patients develop recurrent cancer after their original cancer has been treated. Now, this is a sweeping statement because depending on the stage at diagnosis, patients have different levels of risk for recurrence.

Scott Steele: Yeah. You mentioned stage. So can you talk a little bit about how that stage influences the likelihood of it coming back?

Dr. Haniee Chung: In early stage cancer, so stage one or two where the cancer is contained to the colon itself, the risk of recurrence is low, but not zero. More commonly, recurrence occurs locally, in other words, at the site of the original cancer. In more advanced stage cancer, stage three or four where the cancer has already spread into the lymph system or to other organs, that risk of recurrence increases. And in these cases, the more likely picture is that cancers recur systemically elsewhere in the body, not necessarily just at the site of the original tumor.

Scott Steele: So Haniee, if somebody has an operation, let's just say colon cancer for general, they have an operation and the cancer comes back in a different part of the colon, do we consider that a recurrence or is that a new lesion?

Dr. Haniee Chung: It depends on the timing and the location. So if the tumor recurs right at the site where the patient had surgery initially, that's generally considered a recurrence. Cancer that's found in a different part of the colon is considered primarily a new lesion. And that's one of the reasons why patients with a history of colon cancer need to be surveyed closely with colonoscopy even after their first cancer is treated.

Scott Steele: Yeah, absolutely. So we talked a little bit about how the stage influences the risk of it coming back, but are there other factors that influences the likelihood of it recurring?

Dr. Haniee Chung: Yeah, a large part of it has to do with the stage as we talked about, and then the characteristics of the tumor to begin with. Certain cancers, the cells just behave better or worse than others. Biologically aggressive tumors tend to be higher stage at diagnosis, and even after treatment, they're more likely to return. So there are features of the cancer that we look at after surgery to help determine those risks, to get a sense of how the cancer behaves in the body.

The other really important factor is the quality of the treatment that was given. There are strict quality measures in place to make sure that surgical treatment removes adequate amounts of tissue surrounding the tumor as well as the lymph nodes that drain the tumor so that there's as much assurance that little to no cancer cells are left behind. It's not a guarantee of course, because there could be invisible cancer cells in the body that could cause recurrence down the line, but we do our best to adhere to the principles of oncological clearance to minimize the risk as much as possible.

So receiving initial cancer treatment at an expert center where surgeons have training and experience in cancer surgery is very important. We know from studies that centers that perform a lot of cancer operations have better outcomes including recurrence free survival.

Scott Steele: So we'll get into surveillance and how we follow people after they get initial treatment for colorectal cancer in a bit, but we don't want it to come back. So are there any lifestyle modifications a patient can adapt to to reduce some of their risk of it returning?

Dr. Haniee Chung: Yes and no. There's been a lot of interest in studying things like dietary habits and exercise regimens on the prevention of cancers in general, but studies like that are hard to design. So no one really knows, in the sense that we can't point to data to say that something definitively prevents cancer. The use of certain medicines like aspirin has been proven to be effective in reducing recurrence in certain types of cancer and cases of colorectal cancer, but it's not a universal recommendation.

Some past studies have shown that a high fiber diet can promote gut health and may reduce the risk of developing chronic inflammation and other changes like polyp formation in the colon. So that is something that I recommend to all my patients, particularly because it's such a simple practice and because there are other added health benefits of a high fiber diet like reduced cholesterol and weight management.

Most importantly, and perhaps this falls under lifestyle, but goes along with surveillance, is that once a patient's been diagnosed and treated, they need to undergo close surveillance.

Scott Steele: So on previous podcasts, we talked a little bit about the initial diagnosis, signs, symptoms that may be difficult to distinguish from more routine things like hemorrhoids, but do the signs and symptoms most commonly at the time of recurrence differ at all from the time of initial diagnosis?

Dr. Haniee Chung: Now, the most common symptoms for both an initial diagnosis of cancer and for recurrence of cancer is no symptoms. And this is what's really difficult sometimes for patients because they may have done all the right things, they've gotten their treatment, they're doing their surveillance, and they feel fine, but then they're given a diagnosis of recurrence. When patients do present with symptoms, they can be similar to their initial diagnosis. There are things like changes to bowel habits, blood in the stool, bloating, pain, weight loss, but symptoms can be pretty unreliable. And so objective tests like lab work, imaging studies, and colonoscopy are really key.

Scott Steele: So we talked a little bit about that, but let's dig in here a little bit more. So can you talk about surveillance testing? What are the specific tests and kind of how often do they happen?

Dr. Haniee Chung: Yeah. All patients who carry a diagnosis of colorectal cancer after finishing treatment need to be followed every three to six months for the first two years, and then every six to 12 months for another three years. We don't call a patient cancer-free until they're five years out. Patients need to undergo a history and physical, lab work, including tumor marker tests, CT scans and colonoscopy. It's not one particular test, but the combination of these things and the clinical evaluation to put them all together, that really helps with early detection of recurrence.

Scott Steele: So let's just say that everybody did the right thing and unfortunately, you get a recurrence. What treatment options are available and how do they compare to the initial treatment?

Dr. Haniee Chung: When recurrence is local, in other words, right at the site of the tumor bed, the question is, is it small enough to be re-resected by surgery? If so, then a re-operation may be the best answer. If it's not, then additional therapy like chemotherapy or radiation may be needed to attempt tumor shrinkage to get it to a place where it's small enough for re-resection. When the recurrence is systemic in the lymph system or in distant organs most often, some of the systemic therapy like chemotherapy is recommended first. Colorectal cancers like to go to the liver and the lungs, and in those cases, usually after receiving systemic treatment, those spots can also be evaluated for resectability. So liver resection, lung resection, or local therapy like radiation, targeted chemo and ablation may be possible based on the clinical situation.

Scott Steele: On previous Butts and Guts podcast, we talked about immunotherapy, and I encourage all of our listeners who are interested in this to go back and listen to those episodes. But has immunotherapy changed the landscape for treatment of what we're talking about today, the recurrent colorectal cancer, and particularly for patients who have those maybe specific genetic mutations and/or biomarkers?

Dr. Haniee Chung: Yes. The most encouraging aspect of immunotherapy is that it is a systemic treatment that is very well tolerated, much better than available chemotherapy. It allows for treatment of the whole body with a much better side effect profile than chemotherapy. The other encouraging aspect is that when patients are treated appropriately, we have seen very effective response in some patients. So this is a great option for, say, an elderly patient who would not tolerate surgery or chemotherapy well. It's also a great option for someone who has a very large or widely spread cancer to receive immunotherapy to reduce the size and extent cancer to turn an unresectable cancer into resectable.

But the existing immunotherapeutic agents are only effective against tumors with a specific genetic mutation, and that occurs in a minority of tumors, about 12%. Nowadays in expert centers, all cancer cells are automatically tested for this defect to see if a patient would qualify for immunotherapy. And even in cases where immunotherapy is given and there is good response, surgery is still recommended to remove the tumor bed because of the risk for recurrence. And then of course, not all patients who qualify for and receive immunotherapy is guaranteed to have a good response. The response rate to treatment is stated at about 30 to 40%.

Scott Steele: Great points, and we do go ahead and test the tumors here at the Cleveland Clinic, but what are the most current advances in precision medicine and targeted therapies for recurrent colorectal cancer? And are genetic testing results used to guide any of these treatment decisions?

Dr. Haniee Chung: Yeah, there's a lot of research being done on developing therapies specific to individual tumors. One exciting development is that we can sequence the DNA mutations within tumor cells to be able to measure the levels of the circulating DNA in the blood, both before and after treatment. It's a way for us to monitor genetic material shed by a patient's tumor to check if treatment was effective and to monitor for recurrence. More broad genetic tests can also check for certain mutations that allow us to use or decide not to use certain treatments based on what the tumor is sensitive to.

Scott Steele: So let's look ahead a little bit into the future. So what emerging technologies or treatment approaches show the most promise for our patients with recurrent colorectal cancer?

Dr. Haniee Chung: Yeah. Well, as a surgeon who treats recurrent cancers, I've been particularly excited about advances in technology that help improve the identification and resection of aggressive cancers. Recurrences can be difficult to address surgically oftentimes because the patient has already undergone an operation or even received other types of treatments like radiation, which make the tissues difficult to handle. And the planes between tumor and normal structures can be almost impossible to tell. So work is being done to understand the differences between tumor tissue and scar tissue so that we can perform more accurate surgery. And that's exciting, but it's in very early stages. Other technology, like applying 3D imaging to preoperative patient scans and using that in real time in the operating room to determine accuracy of the anatomy is also promising. But all of these are kind of in progress and work needs to be done before they're ready to use.

Scott Steele: So now it's time for our quick hitters. It's a chance to get to know you a little bit better. So first of all, what was your first car?

Dr. Haniee Chung: It was a '96 Toyota Corolla.

Scott Steele: What is your favorite dessert?

Dr. Haniee Chung: Ice cream.

Scott Steele: Best trip you've ever been on?

Dr. Haniee Chung: I just got back from my honeymoon to Europe. My favorite part of that was visiting Switzerland.

Scott Steele: Beautiful. So finally, if you could go back to your graduating high school self and give them one piece of advice, what would you tell them?

Dr. Haniee Chung: Calm down and relax. It's all going to be okay.

Scott Steele: Fantastic. So give us a final take-home message to our listeners regarding the treatment of recurrent colorectal cancer.

Dr. Haniee Chung: Yeah. Colon cancer and rectal cancer are very treatable even when it's recurrent, but the best chance of successful cancer treatment is the first chance. So seeking cancer treatment at an expert center where providers are cancer-minded is the optimal approach to prevent recurrences in the future.

Scott Steele: That's fantastic. Great advice. And so to learn more about colorectal cancer treatment options, please visit clevelandclinic.org/coloncancercare. That's clevelandclinic.org/coloncancercare. And to make an appointment with a colon cancer specialist, please call our cancer answer line at 866.223.8100. That's 866.223.8100. Dr. Chung, thanks so much for joining us here on Butts and Guts.

Dr. Haniee Chung: Thanks for having me.

Scott Steele: That wraps things up here at Cleveland Clinic. Until next time, thanks for listening to Butts and Guts.