Screening for Colorectal Cancer Based on Risk Level

Colorectal cancer is a significant health concern in the United States, but timely screening can make a world of difference in early detection and treatment. When it comes to colorectal cancer screening, one size does not fit all. The key to effective screening is understanding your risk level and knowing when to start.

If you’re not sure of your personal risk level, or if you should get screened, not to worry. In this article, we'll explore when individuals should begin colorectal cancer screening based on their risk level: average risk, increased risk, and high risk based on the different colorectal cancer risk factors. We also delve into the recommended screening methods for each risk level and how frequently you should get screened.

Individuals at average risk for colorectal cancer are those who do not have any specific risk factors. The following conditions should be met in order to be considered of average risk:

• No personal or family history of colorectal cancer
• No personal history of inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
• No confirmed or suspected hereditary colorectal cancer syndrome, including Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) and familial adenomatous polyposis (FAP)
• No personal history of receiving radiation therapy to the abdominal or pelvic area in treating a prior cancer

Individuals who fall into this category should initiate screening at the age of 4 — 5 years earlier than the previously recommended 50 years of age. The earlier screening age accounts for the rising incidence of colorectal cancer in younger adults, and ensures that the disease is detected as early as possible.

The screening methods and screening intervals recommended for average-risk individuals are stool-based tests such as:

• Fecal occult blood test (FOBT) every year
• Fecal immunochemical test (FIT) every year
• Multitarget stool DNA test every three years
• CT colonography (virtual colonoscopy) every 5 years
• Flexible sigmoidoscopy (FSIG) every 5 years
• Colonoscopy every 10 years

Individuals with an increased risk of colorectal cancer may have family history, certain medical conditions, or other factors that raise their susceptibility. These factors include:

• Family history: If you have a first-degree relative (parent, sibling, or child) who had colorectal cancer or advanced adenomas, you should start screening at age 40 or 10 years earlier than the youngest age at diagnosis within your family, whichever comes first.
• Personal history: If you've had colorectal cancer or certain types of polyps before, your screening should begin earlier and be more frequent, as advised by your doctor.
• Inflammatory bowel disease (IBD): Patients with conditions like Crohn's disease or ulcerative colitis should commence screening earlier and undergo more frequent surveillance.

For increased risk individuals, screening is recommended at age 40 or earlier, as advised by your healthcare provider. The recommended screening methods may include colonoscopy every five years, flexible sigmoidoscopy, or other tests such as a double-contrast barium enema.

High-risk individuals face the greatest likelihood of developing colorectal cancer. This category includes those with certain hereditary conditions, such as Lynch syndrome or familial adenomatous polyposis (FAP). Alternatively, a genetic test reveals high-risk mutation, or radiation therapy to treat a prior cancer in the abdominal or pelvic area would also place you in the high-risk bracket.

In these cases, screening can start as early as adolescence or the late teens (for hereditary or genetic conditions), and it usually involves more frequent monitoring. The recommended methods may include annual colonoscopy or other specialized tests tailored to the specific condition.

These recommendations are broad guidelines, and you should continue to consult with your healthcare provider on the necessity of colorectal cancer screening based on your risk level. As screening when it is not required may impose some personal financial burden, in all cases, your healthcare provider will help you determine the most appropriate screening schedule based on your individual risk factors.