Talking colorectal cancer with U of M

MINNEAPOLIS/ST. PAUL (3/01/2024) — March is National Colorectal Cancer Awareness Month. According to the American Cancer Society, there has been a steep rise in colorectal cancer cases among young adults in recent years. One in five cases are in people 54 years or younger — an 11% increase from 1995. As a whole, in the U.S., colorectal cancer is the third most common cancer among men and women with nearly 150,000 new cases each year.

Emil Lou, MD, PhD, FACP, a physician-scientist and gastrointestinal oncologist with the Masonic Cancer Center, University of Minnesota Medical School and M Health Fairview, answers questions on the symptoms, treatment and screening for colorectal cancer.

Q: What is colorectal cancer?

Dr. Lou: The term colorectal cancer describes all cases of cancer that start in the colon or rectum. Broadly, this term may also be used to describe cancers that start in the small intestines or appendix, which are relatively less common but nonetheless treated similarly. The way I usually describe the anatomy to patients is that we eat food that passes through the esophagus, stomach and into a long and winding part of the digestive tract called the small intestines before passing digested remaining portions to the colon and the rectum. 

Q: How is colorectal cancer detected? What are the symptoms?

Dr. Lou: Colorectal cancer is one of the few cancer types for which we have accessible, validated and approved methods of screening in order to find the cancer early. A central purpose of cancer screening is to detect cancers at an earlier stage, hopefully at a point where it is treatable and even curable. Many cases of colorectal cancer can be first found on a colonoscopy. However, in other patients, the cancer may be found when symptoms develop, such as bleeding in the stool, abdominal pain or other concerning symptoms that require further evaluation. It is vital that people recognize these symptoms and bring it up to their doctors and other care providers as soon as possible if the symptoms cannot be explained by other causes. Early and accurate diagnosis of colorectal cancers can make a difference in improving outcomes.

Q: What is the recommended age to screen for colorectal cancer?

Dr. Lou: For many years, the general consensus from medical experts was for people at average-risk of colorectal cancer to start screenings at age 50. During that time, an exception to this rule was if you have had a close relative — like a parent or sibling — diagnosed with colorectal cancer at a relatively young age. For example, if a parent were diagnosed at age 52, then it would be recommended that their child start colorectal cancer screenings as early as 10 years before the age of their parent’s diagnosis, in this case, age 42. The number of colorectal cancers linked to hereditary causes is surprisingly low, usually less than 10%. Nonetheless, over the past 10-15 years, there has been an alarming overall trend seen in the rise of people under the age of 50 being diagnosed with colorectal cancer; in many cases, they are at advanced stages by the time they are diagnosed, and such cases can be more aggressive and difficult to treat.  This rise led to lots of debate about whether Americans should consider screening sooner than age 50, in order to catch these cases earlier. In 2018, the American Cancer Society and other medical societies recommended lowering the age of first colorectal cancer screening to 45. In the years to come, that guideline may change yet again. No matter your age, if you develop unusual symptoms, including abdominal cramps or bleeding in the stool, that after medical evaluation are not explained by other causes, then colorectal cancer should be considered a potential cause. Talk to your doctors about getting screened. It's one of the few cancers that we have effective screening tests for. 

Q: What are the treatment options for colorectal cancer?

Dr. Lou: The treatment options for colorectal cancer are mainly determined by the stage of the cancer. Stage means how far the cancer is from where it began and is classified as stages 1, 2, 3 or 4. 

Cancers that remain contained and small at the time of diagnosis — considered early stage — may be removed by a surgeon. The surgery, in those cases, is performed with the goal of curing it. The success rate can be very high. When the cancer has escaped into lymph nodes — small sacs that naturally surround our organs and give fluid back to our bloodstream — that means the cancer is in a higher stage, often called stage 3. In this case, a standard recommendation would be surgery followed by some form of chemotherapy, with the goal of reducing the risk that the microscopic cancer cells can spread and cause the cancer to return in the future. Stage 4 is the highest stage and occurs when the cancer has spread to other sites from where it started. Chemotherapy is the standard recommended treatment. In some cases, if there is very limited spread, surgery may also be offered. Over the past decade, there have been a lot of promising advances in genomic testing of tumors. More and more, we can use that information to tailor treatment to an individual patient’s form of cancer using targeted therapy and possibly immunotherapies. These advances show a lot of promise for treating this form of cancer more effectively.

Q: What are you doing to advance colorectal cancer research?

Dr. Lou: In addition to treating patients with gastrointestinal cancers at the Masonic Cancer Center, I am a researcher. I lead a laboratory that investigates colorectal cancers at the cellular and molecular levels, with the goal of trying to figure out how these cancer cells communicate with each other and how this communication is vital to the growth of tumors. If this communication is truly as critical as we believe, then stopping or interfering with it would be a unique way we can halt tumor growth and stop colorectal cancers. 

I also lead efforts to integrate new technologies, such as application of molecular diagnostics, to understand new ways we can treat patients. In several ongoing studies with collaborators at the University of Minnesota and the National Institutes of Health, we are examining new molecular changes discovered in tumors from patients treated at the University. We believe some of these mutations may give us better insight into what drives the formation of colorectal cancers and why some forms are more resistant to treatment. Above all, my team and I are dedicated to advancing colorectal cancer research because we owe it to all patients — past, current and future — to find ways to better treat this cancer and aim for cures.

Dr. Emil Lou is an oncologist at the University of Minnesota Medical School and M Health Fairview. His areas of expertise include colorectal, pancreatic, esophageal and gastric cancers.

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