Colon cancer, also known as colorectal cancer, is the second-leading cause of cancer deaths in men and women in the world. In 2020, 915,880 died of colon cancer, including rectal cancer.

The good news is colon cancer is one of the few forms of cancers that can be easily prevented with timely and appropriate screening. As men and women over the age of 45 have become more aggressive about getting screened, combined with making healthy lifestyle choices to reduce risk factors, the incidence of colorectal cancers has been declining since the mid-1980s.

What are the major risk factors for colorectal cancer?

• Age – As we get older, the chance of developing this cancer increases. However, there has been an increase in younger patients getting aggressive colorectal cancers.

• Obesity – As obesity increases among the American population, the risk of colorectal cancer also increases.

• Smoking – Smokers are more likely to develop this cancer than nonsmokers.

• Family history – Genetics are a major risk factor for developing colorectal cancer in families. Certain genes have been identified as signs of potential colorectal cancer. In addition, personal history of inflammatory bowel disease, such as ulcerative colitis and Crohn’s, increases risk of developing colorectal cancers.

• Activity level – Physically inactive people are at higher risk of developing colorectal cancer.

• Alcohol – Colorectal cancer has been linked to moderate and heavy alcohol use.

Anyone with risk factors should consult their physician for appropriate recommendations for a screening procedure. Early detection is key to long-term survival. Unfortunately, during the pandemic, many people delayed or canceled their colonoscopy screening.

Fortunately, post-COVID-19 screening rates have returned to near normal, but EPIC Research reports “it might take years to fully realize the impact of missed screening over the last three years.” In addition, the American Cancer Society reports the percentage of cases diagnosed with advanced stage colorectal cancer increased from 52% in the mid-2000s to 60% in 2019.

Staging for colorectal cancer

Staging is conducted with the help of colonoscopies, CAT scans and blood work. In rectal cancer, diagnostic testing via magnetic resonance imaging and rectal ultrasound are required to appropriately stage the cancer.

Stages 1 and 2 have the best prognosis. These are cancers limited to the wall of the colon and rectum. The main treatment for these early stage cancers is surgery, which has proved curative for most patients. If the tumor has progressed to stage 3, colon cancer can only be established after surgery and patients will require chemotherapy to cure and prevent recurrence.

For stage 4 patients, the prognosis is worse, which is why the goal is always early detection to prevent late-stage diagnosis whereby the treatment remains either chemotherapy and/or targeted therapies.

Colonoscopies are still the best screening available

A colonoscopy remains the “gold standard” in screening for colorectal cancer. There are newer colorectal cancer screening tests such as DNA-based testing, Cologuard or the fecal immunochemical test. For people with average risk, tests have become good alternatives to a colonoscopy. However, patients who test positive from noninvasive screenings will require a colonoscopy.

There remain challenges to providing testing. There is a disparity in access, as well as an acute shortage of gastroenterologists to meet the increasing number of people who need screening procedures. Worse, the rate of people getting screened is much lower in Black and Hispanic populations.

Even with testing issues, the survival rate for colon cancer patients – even those with late-stage disease – is much better today than two decades ago. The five-year survival rate for stage 3 colorectal cancer ranges between 70% to 75% depending on the age of the patient at diagnosis. The survival rate dropped to 35% to 40% for stage 4 cancer. Early detection of cancers in stages 1 and 2 has a five-year survival rate of more than 90%.

Life after cure

The medical community treats colon cancer patients like they have a chronic illness. Survivorship programs and developing a healthy lifestyle to prevent other cancers are important to ensure the cancer does not come back. Good food, healthy nutrition, exercise and supplements, including vitamin C, may play a role in prevention. Routine checkups, including scheduled colonoscopies, are extremely important. Many patients suffer long-term side effects because of the treatment, which may need to be addressed by a specialist. Integrated medicine programs always are very helpful for these patients.

If you are 45 or older, schedule your colonoscopy. If for some reason you cannot get one, consider alternate screening such as a FIT or Cologuard test.

• Pankaj Vashi, MD, AGAF, FASPEN, is the vice chief of staff and medical director of gastroenterology/nutrition and metabolic support at City of Hope Chicago. Dr. Vashi works in the City of Hope GI Cancer Center as part of a multidisciplinary team of cancer experts.