From the Guidelines
High-risk patients for colon cancer include those with a family history of colorectal cancer, especially first-degree relatives diagnosed before age 60, and individuals with inherited syndromes such as Lynch syndrome or familial adenomatous polyposis (FAP) 1. These individuals are at a higher risk of developing colon cancer due to genetic mutations or chronic inflammation. Other high-risk groups include:
- Patients with inflammatory bowel disease (particularly ulcerative colitis or Crohn's disease with colonic involvement) 1
- Those with a personal history of colorectal cancer or advanced adenomatous polyps 1
- Individuals with certain racial backgrounds, particularly African Americans 1 Additional risk factors include:
- Obesity
- Smoking
- Heavy alcohol consumption
- Diets high in red or processed meats
- Physical inactivity Age is also a significant factor, with risk increasing substantially after age 50 1. These high-risk patients typically require earlier screening, often beginning at age 40 or 10 years before the youngest affected relative's diagnosis, and more frequent surveillance with colonoscopy rather than less invasive screening methods 1. The increased risk stems from genetic mutations, chronic inflammation, or lifestyle factors that promote abnormal cell growth in the colon's lining, potentially leading to polyp formation and eventual malignant transformation. It is essential to identify these high-risk individuals and provide targeted surveillance and management to reduce the risk of colon cancer and improve outcomes 1.
From the Research
Characteristics of High-Risk Patients for Colorectal Cancer
- Patients with a positive family history have an increased risk of colorectal cancer (CRC) 2
- Defined familial syndromes associated with extremely high risks of CRC, such as hereditary non-polyposis colorectal syndrome or familial adenomatous polyposis, require specialized management approaches 2, 3
- Individuals at increased risk of developing colorectal cancer include those with a personal or family history of advanced adenomas or colorectal cancer, a personal history of inflammatory bowel disease, or genetic polyposis syndromes 4
- Between 3 and 6% of all CRCs are attributed to well-defined inherited syndromes, including Lynch syndrome, familial adenomatous polyposis (FAP), MUTYH-associated polyposis (MAP), and several hamartomatous polyposis conditions 3
- 20%-30% of all colon cancer cases have a potentially definable inherited cause, and 3%-5% of colon cancers occur in genetically defined high-risk colon cancer family syndromes 5
Specific High-Risk Groups
- Individuals who have a first-degree relative with colorectal cancer or advanced adenoma diagnosed before 60 years of age or two first-degree relatives diagnosed at any age should be advised to start screening colonoscopy at 40 years of age or 10 years younger than the earliest diagnosis in their family, whichever comes first 4
- Individuals with ulcerative colitis or Crohn disease with colonic involvement should undergo colonoscopy starting eight to 10 years after the onset of symptoms and be repeated every one to three years 4
- Individuals who have a first-degree relative with hereditary nonpolyposis colorectal cancer should begin colonoscopy at 25 years of age and repeat colonoscopy every one to two years 4
- Persons with a family history of adenomatous polyposis syndromes should begin screening at 10 years of age or in a person's mid-20s, depending on the syndrome; repeat colonoscopy is typically required every one to two years 4
- Screening colonoscopy should begin at eight years of age in individuals with Peutz-Jeghers syndrome 4