Transcript:John L. Marshall, MD: Hello, and thank you for joining this OncLive Peer Exchange, “The Biology of Extending Survival in Metastatic Colorectal Cancer.” Research is helping define subsets in colorectal cancer that, increasingly, impact everyday clinical practice. The resulting enhanced understanding of the underlying biology of the disease has led to a more nuanced treatment approach.

I’m Dr. John Marshall, and I’m professor and chief of the Division of Hematology/Oncology at Georgetown University Hospital, and I’m the director of the Ruesch Center for the Cure of GI Cancers in Washington, DC. In this OncLive global Peer Exchange, I welcome our panel of international experts in gastrointestinal cancers, who will discuss today’s evidence-based strategies in advanced disease. The discussion will also include emerging data in immunotherapy, targeted therapy, and an update in tumor sidedness. Joining this discussion are very good friends of mine: Dr. Dirk Arnold, a medical oncologist, a professor, and the head of Instituto CUF de Oncologia in Lisbon, Portugal, and a professor of medicine at the University of Hamburg in Germany. Dirk, welcome.

Dirk Arnold, MD, PhD: Thank you, John.

John L. Marshall, MD: Second, Dr. Fortunato Ciardiello, full professor of medical oncology and director of the Department of Clinical and Experimental Medicine at Seconda Università di Napoli in Naples, Italy. Fortunato, welcome.

Fortunato Ciardiello, MD, PhD: Thank you.

John L. Marshall, MD: Dr. Paul Helft, a longtime friend and professor of medicine for the Division of Hematology/Oncology at the Indiana School of Medicine of the Indiana University Melvin and Bren Simon Cancer Center in Indianapolis, Indiana. Paul, welcome.

Paul R. Helft, MD: Thank you.

John L. Marshall, MD: And Dr. Tony Bekaii-Saab, a very good friend of mine and a professor at the Mayo Clinic College of Medicine and the science coleader of the GI Cancer Program at the Mayo Clinic Cancer Center in Arizona. Tony, welcome.

Tanios Bekaii-Saab, MD: Thank you, John.

John L. Marshall, MD: Thank you for making it here on an early morning, here in Chicago, at the 2017 ASCO Annual Meeting. It’s been a big meeting, and a lot of important stuff is emerging around colon cancer. Our audience out there wants to know how this stuff impacts their day-to-day treatment, so let’s dive right in. I want to start by discussing what, to me, has just totally changed my practice—I didn’t sign up to take care of kids with colon cancer. I’ve got a 17-year-old with stage 3 colon cancer. We’re all seeing an emergence of these young folks with colon cancer. Paul, tell us a little bit about what you’re seeing and some of the emerging data around young people with colon cancer.

Paul R. Helft, MD: This is really an interesting story. If you would ask those of us who’ve always practiced in academic medical centers, we’ve always thought that colon cancer was a disease of younger people, in fact. On average, we see patients 10 to 20 years younger than the median for United States adults, and the same is largely true in European centers as well. But it’s very clear, even though data have suggested for decades that—at least in United States populations—the median age of incidence of colorectal cancer has been relatively stable at around age 70, younger people are getting it more often. And in fact, if you look at the population at large, we have seen as much as a 50% increase in patients, overall, under the age of 50—which is the age, at least in United States adults, where we begin to screen patients for colorectal cancer in the first place.

John L. Marshall, MD: Fortunato, is this happening in your practice too? Or is this a United States problem?

Fortunato Ciardiello, MD, PhD: I am afraid the disease will probably become a problem, more and more, worldwide. I don’t know the causes. It could be that in Europe, we are using the Anglo-Saxon American style of eating. We are not using the Mediterranean diet that is protecting us much more than a diet that is very rich in meat. I don’t know. But really, we are seeing younger and younger patients— although, in the general population, the prevalence is still in patients 60 to 65 years or older.

Basically, we face 2 different groups of patients: very young patients and patients who are in the elderly stage of their life. And then we have the problems as to whether they are fit or not, or if there are other comorbidities that appear, very often, in this age of patients. We will have 2 different types of patients whom we have to deal with, and the way to screen the general population will become a major issue.

John L. Marshall, MD: We’ll talk about that, but is this something molecular? The first question I always have when I have any patient nowadays, but a young patient specifically, is, are they MSI-high? And most of the time, these are not Lynch syndrome patients, right?

Dirk Arnold, MD, PhD: That’s true. Yet if you go to the Gulf region, or if you go to the far Middle East, you have an even younger population—a high proportion of patients approaching the end of their 20s and their early 30s being diagnosed with colon cancer. Genetically, this is not understood. It’s not a typical alteration. It’s not a typical germ line mutation, or whatever we do see, which explains this phenomenon.

John L. Marshall, MD: When we compare next-generation sequencing of young versus old patients, we’re not seeing a big, different pattern. It’s that it’s colon cancer as we know it to be, but it’s not very different. Should we change our screening guidelines? In Europe, you guys are screening at what age? At 50?

Dirk Arnold, MD, PhD: Yes.

Fortunato Ciardiello, MD, PhD: Yes.

John L. Marshall, MD: Is it a colonoscopy? Or is it fecal occult blood testing? Where are you with that?

Fortunato Ciardiello, MD, PhD: Fecal blood testing is the first type, at least in Italy. And then, if it’s positive, we go to colonoscopy.

John L. Marshall, MD: In Germany, what is it?

Dirk Arnold, MD, PhD: In Germany, it’s colonoscopy country. We offer a colonoscopy to anyone at the age of 50 or older, and we skip fecal occult blood testing. We offer it to only those individuals who do not like to undergo a colonoscopy. And unfortunately, the pick-up rate for colonoscopy is not great; therefore, this stresses the necessity to have a stepped approach—first, potentially do a fecal or a blood test and then have a colonoscopy done to increase the acceptance rate, although it’s offered.

Fortunato Ciardiello, MD, PhD: That’s why occult blood testing in the feces is done in Italy. Otherwise, the acceptance in the general population would be very, very low—of the colonoscopy.

John L. Marshall, MD: You certainly get a higher acceptance. It’s cheaper. It’s of proven benefit.

Fortunato Ciardiello, MD, PhD: The positivity, in general, is between 10% and 20%, and only 10% to 20% of people screened go to endoscopy.

Transcript Edited for Clarity