Although sporadic colon cancer accounts for approximately 95 percent of all colon cancers, the incidence of hereditary colon cancer has been rising and is increasingly being detected in younger patients, according to Zane Cohen, MD, FACS, FRCSC, director, Zane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, and professor of surgery, University of Toronto, ON.

Dr. Cohen will discuss the evolving science and surgical best practices related to hereditary colon cancer, particularly Lynch syndrome, during Tuesday’s Herand Abcarian Lecture, Privilege and Responsibility: A 20-Year Journey.

“Over the last 20 years, we have learned a great deal about the genetics of hereditary colon cancer, and it seems that every year or two there are new genetic syndromes that involve colon cancer that are coming to the fore,” Dr. Cohen said. “If you look at the worldwide population of colon cancer, and particularly in North America, the actual numbers of colon cancer are decreasing slightly. But we are seeing more younger patients under the age of 50 who are developing colon cancer.”

In that younger cohort, an estimated 40 to 50 percent of patients will have a pathogenetic variant (genetic mutation) that can be identified, Dr. Cohen noted.

“It’s this newer trend of younger patients who are developing colon cancer that we really need to be aware of,” he added. “A lot of them are going to have a pathogenetic variant, and that means that the surgical procedure may be different, the prophylaxis for them may be different, everything may be different.”

Younger patients with hereditary colon cancer may be at higher risk for developing other cancers, Dr. Cohen said, and surgeons may want to consider sending them to a genetic counselor as part of a team management approach. Family histories, he added, are especially important in these patients.

“When you have a patient sitting across from you in your office and you’re talking about colon cancer, you have to be aware of the family history,” Dr. Cohen said. “You have to be aware of what form of colon cancer they have, what syndrome they fall into, and you have to understand that you have a responsibility to that patient and to their whole family to get them to proper care.”

Proper care, he emphasized, means more than just testing and treating the patient.

“If you test them and they’re positive, you have a responsibility to ensure that their whole family is tested,” Dr. Cohen said. “Some might say that’s not the job of the surgeon, that it’s the job of the genetic counselor. But the genetic counselor doesn’t identify them—we identify them. They have to be followed, and I think we have to take the lead in making sure that happens.”