Identify your risk level for colon cancer. Then share the results with your doctor.
The American Cancer Society recommends that people with an average risk of colorectal cancer (CRC) start screening at age 45.1,2 However, people with higher risks may need to consider screening sooner.1,3,4 Use this downloadable question guide that includes points to cover when you meet with your doctor.
A: The age at which you should get your first colorectal screening depends on a variety of risk factors which you should discuss with your doctor.1 The American Cancer Society recommends people with average risk factors get screened starting at age 45 and at regular intervals thereafter.1 People with higher risk for CRC may need to be screened earlier and more frequently as recommended by their physician.1-4
A: Some of the most common risk factors for colorectal cancer are:
Age. Your risk of colorectal cancer increases with age. About 90% of cases occur in people who are 50 years old or older.4 Although rates have declined in people over the age of 50 and are rising in people under 50 years of age.1,2,4
A personal or family history of colorectal cancer or colorectal polyps.1,2,4,5
Obesity. "Increased waist circumference in adulthood alone is associated with a 53% increased risk of colon cancer."6
Having inflammatory bowel diseases, such as Crohn's disease or ulcerative colitis or diverticulitis.1,3
Ethnic background. Risk factors for the early development of colorectal cancer in young adults (30s and 40s), include people of African or Asian descent.1,7
A sedentary lifestyle. A lack of physical activity increases your risk of colorectal cancer. Regular exercise may reduce your risk.8
Smoking increases the risk of developing colorectal polyps two to three times.8
Dietary habits and obesity. Western diets rich in red meat and processed foods may increase your risk for colon cancer.6,8,9
Diabetes. Those with diabetes or insulin resistance are at a greater risk for colorectal cancer.1
A: Colorectal cancer is the third leading cause of cancer-related deaths in the United States.6 Colorectal cancer is a common and preventable cancer.1 In the Western world, the lifetime risk of CRC is around 5%.8 In the United States, approximately 145,600 cases of CRC are diagnosed annually.1
A: There are many screening options available, including stool test, flexible sigmoidoscopy, CT colonography (virtual colonoscopy), and colonoscopy.1 Doctors can identify and remove polyps during a colonoscopy procedure.10, 11 Meet with your healthcare provider to discuss whether you should get screened and which screening method is right for you.
CRC screening also has potential harms. Harms are associated with injury to the colon or other complications related to colonoscopy. The primary harms from screening colonoscopy include perforation and bleeding, which occur more commonly if polypectomy is performed. The harms are small but increase with age, primarily because the possible complications from colonoscopy (bleeding, infection, or a hole in the intestine) increase with age.2
A: Polyps are mushroom-shaped growths that can occur on the inside walls of your colon. They can become cancerous over time, and spread to other areas of the body. About two-thirds of colon polyps are the precancerous type known as adenomas.9 However, only 5% of adenomas progress to cancer.9
A: Adenoma detection rates are the percent of screening colonoscopies performed by a physician that detect one or more confirmed adenomas or adenocarcinomas (poylps).11
ADR is a quality benchmark used by medical societies. Currently, professional societies recommend adenoma detection rates of 15% or higher for women and 25% or higher for men, as 25% or higher for patients as indicators of adequate colonoscopy.1,11 Each 1% increase in ADR is correlated with a 3% risk reduction of developing colon cancer.11 ADR rates vary among doctors and patients can inquire about a physician's ADR rate when selecting a physician.11
Ahmed M. Colon Cancer: A clinician’s perspective in 2019. Gastroenterology Research. 2020;13(1):1–10
Wolf AMD, Fontham ETH, Church TR, et al. Colorectal cancer screening for average-risk adults: 2018 guideline update from the American Cancer Society. CA: a cancer journal for clinicians. 2018; 68(4):250–281.
Gausman V, Dornblaser D, Anand S, et al. Risk factors associated with early-onset colorectal cancer. Clinical Gastroenterology and Hepatology. 2020;18(12):2752–2759.
Bailey CE, Hu C-Y, You YN, et al. Increasing disparities in the age-related incidences of colon and rectal cancers in the United States, 1975-2010. JAMA surgery. 2015.
Sekiguchi M, Kakugawa Y, Nakamura K, et al. Family history of colorectal cancer and prevalence of advanced colorectal neoplasia in asymptomatic screened populations in different age groups. Gastrointestinal Endoscopy. 2020;91(6):1361–1370.
Schaberg MN, Smith KS, Greene MW, Frugé AD. Characterizing demographic and geographical differences in health beliefs and dietary habits related to colon cancer risk in U.S. adults. Frontiers in nutrition. 2020;7:568643.
DeSantis CE, Siegel RL, Sauer AG, et al. Cancer statistics for African Americans, 2016: Progress and opportunities in reducing racial disparities. CA: A Cancer Journal for Clinicians. 2016;66(4):290
Øines M, Helsingen LM, Bretthauer M, Emilsson L. Epidemiology and risk factors of colorectal polyps. Best Practice & Research Clinical Gastroenterology. 2017;31(4):419–424.
They found colon polyps: now what? Follow-up exams at the right time are essential to prevent cancer from developing. Harvard men’s health watch. 2013;18(1):5.
Ransohoff DF. How much does colonoscopy reduce colon cancer mortality? Ann Intern Med. 2009;150(1):50–52.
Corley DA, Jenson CD, Marks AR JR, et al. Adenoma detection rate and risk of colorectal cancer and death. The New England Journal of Medicine. 2014;370:2539–2541.