The criteria for defining high-risk most commonly includes ages between 50-74 and other criteria, such as family history, based on clinical practice guidelines.
However, many screening programs do not include individuals at high risk. Some screening registries have similar screening recommendations for increased risk and high-risk individuals, and high or increased risk individuals may still be reached through population-based screening programs intended for individuals at average risk.
Definitions of high-risk for colorectal cancer
| P/T |
Target age |
Definition of high risk |
| YT |
- Age 50, or 10 years earlier than the age their relative was diagnosed with colorectal cancer, whichever comes first
|
- People who are asymptomatic and have a family history of colorectal cancer that includes one or more first-degree relatives (parent, sibling, or child) diagnosed with the disease
|
| NT |
- Age 40, or 10 years earlier than the youngest relative’s age at diagnosis, whichever comes first
|
- Based on clinical guidelines
|
| NU |
|
- Based on clinical guidelines; refer to specialist
|
| BC |
- 10 years prior to diagnosis of first-degree relative with colon cancer
|
– |
| AB |
- Depends on family history or genetic syndromes
|
- High-risk conditions such as Lynch syndrome or familial adenomatous polyposis
|
| SK |
|
|
| MB |
- Age 40, or 10 years earlier than the youngest relative’s age at diagnosis, whichever comes first
|
- Family history of one first-degree relative diagnosed with colorectal cancer before age 60 or two or more first-degree relatives diagnosed with colorectal cancer at any age.
- Personal history of CRC or high-risk adenomas requiring surveillance, irritable bowel disease (IBD) with associated colitis, or confirmed Lynch syndrome or Familial adenomatous polyposis (FAP)
- The program does not intentionally recruit high-risk individuals for FIT screening. High-risk individuals can access colonoscopy screening through healthcare provider
|
| ON |
|
- High-risk people are managed outside screening program
|
| QC* |
– |
– |
| NB |
N/A |
- Based on clinical guidelines; high-risk definition is not specified. Guideline definitions use the terms average risk and not-average risk
|
| NS |
- Depends on genetic syndrome
|
- High-risk individuals should access colonoscopy through their healthcare provider
|
| PE |
- Depends on genetic conditions
- Hereditary nonpolyposis colorectal cancer (HNPCC): Start at age 20, or 10 years younger than affected relative for those with HNPCC
- Familial adenomatous polyposis (FAP): Start age between 10–12 for those with FAP
- Attenuated adenomatous polyposis coli (AFAP): Start age between 16–18 for those with AFAP
|
- The increased risk definition in guidelines includes high-risk individuals with a genetic condition of HNPCC, FAP, or AFAP
- High-risk individuals are not identified by the program. Individuals 50–74 with any increased risk are invited by letter to self-identify their condition and discuss screening option with PCP
|
| NL |
|
- High-risk individuals should access colonoscopy through their healthcare provider
|
*QC: Monitoring and management algorithms have been revised based on risk and clinical follow-up according to pathology. There are currently three risk categories : moderate risk, slightly increased risk and moderately increased risk. High-risk individuals are included in the moderately increased risk algorithms, but do not have their own specific definition or algorithm.
-No information was provided at the time the data were collected.
Recommendations for individuals at high-risk of colorectal cancer
| P/T |
Screening recommendation for high-risk population |
Follow-up recommendation after normal colonoscopy |
| YT |
- Participants with high-risk adenoma(s) identified are recalled for colonoscopy in 2-3 years
- Participants with a strong family history are referred at age 40, or 10 years prior to index case, whichever comes first
- Participants with a personal history of adenomas who have high risks polyp(s) identified are recalled for colonoscopy in 2–3 years
|
- After a normal colonoscopy, participants are recalled for colonoscopy in five years; FIT not recommended
- Participants with a strong family history and normal colonoscopy are recalled for colonoscopy in five years; FIT not recommended
- Participants with a personal history of adenomas and normal colonoscopy are recalled for colonoscopy in five years; FIT not recommended
|
| NT |
|
|
| NU |
- Refer to specialist (out of Territory) for tailored screening
|
- As per specialist recommendations
|
| BC |
- 10 years prior to diagnosis of first-degree relative
|
|
| AB |
- Individuals with high-risk conditions are outside the recommendations of the Alberta Colorectal Screening Program
- Individuals with high-risk conditions should have an established relationship with either a local CRC screening centre or an endoscopist for ongoing care and monitoring
|
|
| SK |
- FIT is not recommended; refer directly to colonoscopy as per guidelines
|
|
| MB |
- Screening through colonoscopy
|
- Participants at high risk due to family history should get colonoscopy every 5–10 years starting at age 40, or five years earlier than the youngest relative’s diagnosis
- Participants at high risk due to personal history should seek surveillance and manage as directed by endoscopist
|
| ON |
- The program does not currently have recommendations for screening people at high risk of colon cancer due to hereditary colon cancer syndromes. People who are at high risk should not be screened with FIT and should talk to their doctor about how and when to get screened*
|
N/A |
| QC |
|
|
| NB |
- See clinical guidelines for not-average risk screening
|
|
| NS |
- Participants at high risk due to family history suggesting inherited cancer syndrome should get genetics testing and follow high-risk screening guidelines based upon results
|
|
| PE |
- Colonoscopy screening for those with HNPCC
- Sigmoidoscopy screening for those with FAP
- Colonoscopy screening for those with AFAP
|
- Colonoscopy every 1–2 years for those with HNPCC
- Annual sigmoidoscopy for those with FAP
- Annual colonoscopy for those with AFAP
|
| NL |
- Specialist care recommended for those with FAP or AFAP, HNPCC or Lynch syndrome, IBS, or other identified genetic mutation
|
|
*ON: Ontario’s Ministry of Health provides funding for genetic testing for Lynch syndrome based on criteria set by the Ministry. Ontario Health (Cancer Care Ontario) also provides funding to select labs in the province to perform reflex testing to screen for Lynch syndrome in patients under 70 years of age with invasive colorectal cancer (CRC) and endometrial cancer tumours
Abbreviations:
- AFAP: Attenuated adenomatous polyposis
- FAP: Familial adenomatous polyposis
- HNPCC: Hereditary nonpolyposis colorectal cancer
