Colorectal cancer is a cancer of the colon or rectum, which is also known as your large intestine. The American Cancer Society estimates that there will be 104,610 new cases of colon cancer and 43,340 new cases of rectal cancer in the United States in 2020.

With colorectal cancer our goal is to identify it before it becomes cancer or during the very early stages of disease. A procedure called a colonoscopy gives a gastroenterologist a direct view of the colon. Through this procedure we can identify a polyp – a little extra bit of tissue in the colon -- that may become colon cancer. If we see a polyp, we remove it during the procedure, so it doesn’t grow into a cancer. The polyp is then sent for further testing to determine if it is pre-cancerous or cancerous.  

What are colorectal cancer risk factors?

There are various colorectal cancer risk factors. I like to stress to my patients that there are some colorectal cancer risk factors that we can change, modify and decrease, while there are others we can’t change or decrease (such as family history or genetics).

The colorectal cancer risk factors that we may be able to change are often related to making healthier lifestyle choices. These lifestyle changes are the same recommendations that reduce your risk of heart disease and can lead to better overall health when we practice healthy habits.

Colorectal cancer risk factors that we can modify:

  • Being overweight: extra weight increases the colon cancer risk in both men and women, but more in men. Making healthy food choices and eating a balanced diet can help you lose weight.
  • Physical inactivity: not getting physical activity increases your colon cancer risk. Even walking or light exercise can help your overall health and decrease your risk of disease.
  • Eating healthy: a diet high in red meat and processed foods such as beef, hot dogs, pork and some lunch meats are linked to a higher risk for colorectal cancer.
  • Smoking: smoking increases your risk of ALL cancers including colorectal cancer. Quitting smoking can decrease colorectal cancer risk, as well as heart disease and other conditions.
  • Drinking alcohol: moderate to heavy alcohol intake is associated with an increased colorectal cancer risk so limit your intake to no more than two drinks a day for men and one drink a day for women. Sometimes your doctor may recommend no alcohol at all, based on your other medical illnesses or conditions.

Colorectal cancer risk factors that we cannot modify:

  • Genetics: some individuals may have a genetic makeup that gives them a higher risk of growing polyps or developing colorectal cancer.
  • Age: anyone can get colorectal cancer at any age; however, the risk of colon cancer increases with age and it is more common after ages 45 to 50.
  • Medical history: a prior personal history of polyps increases your risk of colorectal cancer. Your doctor may recommend more frequent colonoscopies to remove polyps as they grow and prevent them from becoming cancerous.
  • Certain medical conditions: patients with chronic inflammation of the colon such as in Crohn’s Disease or ulcerative colitis are at an increased risk and screening should begin much earlier than the standard ages of 45 to 50. You should be under the care of a gastroenterologist for these conditions, and your gastroenterologist will alert you when you should start screenings.
  • Family history: having colorectal cancer in the family or a family history of colon polyps increases your risk of colon cancer, and you need to start screening early. It’s important to talk to family members and find out if they had polyps or cancers identified during their colonoscopies
  • Genetic syndromes: about five percent of the population have a genetic syndrome that puts them at an increased risk for colon cancer and other cancers. One of these conditions is Lynch Syndrome. Patients with this syndrome tend to develop colon cancer at younger ages, even before they have a chance to grow a polyp. If a family has a history of many cancers or cancers in young people, they should see a genetics specialist to see if they have a high-risk syndrome.

Are some groups at a higher risk?

It’s important to note that individuals from certain racial and ethnic backgrounds have been found to be at an increased risk for colorectal cancer. We do not understand necessarily why this is but notice a higher risk in the following groups:

  • African Americans. This group has the highest incidence of colorectal cancer of all race groups in the United States.
  • Jewish individuals of Eastern European descent (Ashkenazi Jews). This group has one of the highest risks of colorectal cancer in the world.  
  • Patients with type 2 diabetes. This typically applies to non-insulin dependent diabetics. Because of the known increased risk, it is recommended that you speak to your doctor to determine if you should start screening earlier.

The importance of family history

We consider colorectal cancer to be a preventable disease. That’s why a family history is so important. When I meet a patient, I spend a lot of time taking a detailed family history. This helps to identify if a patient may be in one of the groups of individuals who are at higher risk for colon cancer (among other cancers) and this helps to determine at what age screenings should begin.

The best advice I can give to all patients is to make lifestyle changes to help you take better control of your overall health. These include a balanced, healthy diet with moderate exercise. Even just taking a walk or using the stairs instead of the elevator can help improve your overall health. Also, spend time talking to your family and learning about your family medical history. You can discover trends that can be brought to your doctor’s attention and determine if you should see a GI specialist to start screening early. You’re never too young to have that conversation.

You can learn more about colorectal cancer and colonoscopy here.

Dr. Sarah Hyder

Sarah M. Hyder, MD

Dr. Sarah Hyder is the director of endoscopic ultrasound at Rhode Island Hospital, specializing in pancreatobiliary disease and therapeutic endoscopy as a gastroenterologist at Lifespan Physician Group Gastroenterology.