Colorectal Cancer – Epidemiology

Epidemiology

  • Colorectal cancer is the third most common cancer worldwide1 and represents 8.1% of all new cancer cases in the United States.2
  • Colorectal cancer affects up to 5% of the population, with 150,000 new cases each year in the United States alone.3
  • Approximately 51,000 people in the United States will die from colorectal cancer in 2019.4
  • About 40% of patients with colon cancer have localized cancer that can be treated surgically.2,5 The 5-year relative survival of patients with localized CRC is 90%.2
  • The 5-year survival rate of patients with metastatic CRC (mCRC) is 13.8%.2
  • An estimated 64.5% of individuals with CRC survive 5 years or more.2
  • About 5% of people who develop colon cancers have a hereditary link.6
  • Colorectal cancer is most frequently diagnosed among people aged 65–74 years. The median age at diagnosis is 67 years, and the median age at death is 73 years.2

Risk factors

  • Lifestyle factors such as being overweight or obese, physical inactivity, smoking, heavy alcohol use, and diets high in red and processed meat (particularly if fried, broiled, or grilled) increase the risk of colorectal cancer.6 High dietary fiber intake may decrease the risk of CRC.7
  • Older individuals have the highest rates of CRC, which is much more common after age 50 years.4,6 Incidence rates declined by 3.7% in adults ≥55 years of age but increased by 1.8% in those younger than age 55 years from 2006 to 2015.4
  • Patients with a history of adenomas (particularly if greater than 1 cm) and CRC are at increased risk of developing CRC.7
  • A history of CRC or adenomatous polyps in a first-degree relative (parent, sibling, or child) increases the risk of developing CRC. The risk is higher if a relative was diagnosed with cancer before the age of 45. Individuals with a family history of CRC may need to be screened before the age of 45.6
  • Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease, leads to chronic inflammation of the bowel and dysplasia. IBD increases the risk of developing CRC.6
  • Approximately 5% of people who develop CRC have an inherited syndrome that predisposes them to the disease.6
    • Lynch syndrome accounts for 2–4% of CRC cases. This syndrome is often caused by a mutation in the MLH2 or MSH2 DNA repair genes and carries an 80% lifetime risk of CRC.
    • Familial adenomatous polyposis accounts for 1% of all CRC cases. This syndrome is caused by a mutation of the APC gene and leads to the development of hundreds or thousands of polyps, often starting at the age of 10 or 12 years. Almost all individuals with this syndrome will develop CRC by the age of 40.
    • Peutz-Jeghers syndrome (PJS)
    • MYH-associated polyposis (MAP)

References

  1. Bray F, Ferlay J, Soerjorataram I et al. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018;68:394-424.
  2. National Cancer Institute. SEER Cancer Stat Facts: colorectal cancer. https://seer.cancer.gov/statfacts/html/colorect.html
  3. Johns Hopkins Medicine. Sporadic (nonhereditary) colorectal cancer. https://www.hopkinsmedicine.org/gastroenterology_hepatology/_pdfs/small_large_intestine/sporadic_nonhereditary_colorectal_cancer.pdf
  4. American Cancer Society. Cancer Facts & Figures 2019. https://www.cancer.org/content/dam/cancer-org/research/cancer-facts-and-statistics/annual-cancer-facts-and-figures/2019/cancer-facts-and-figures-2019.pdf
  5. Johns Hopkins Medicine. Colorectal cancer center. https://www.hopkinsmedicine.org/kimmel_cancer_center/centers/colorectal_cancer/about_colon_cancer/
  6. American Cancer Society. Colorectal cancer risk factors. https://www.cancer.org/cancer/colon-rectal-cancer/causes-risks-prevention/risk-factors.html
  7. American Cancer Society. Colorectal Cancer Facts & Figures 2017–2019. https://www.cancer.org/content/dam/cancer-org/research/cancer-facts-and-statistics/colorectal-cancer-facts-and-figures/colorectal-cancer-facts-and-figures-2017-2019.pdf