There are several credible tools available to help you better understand your breast cancer risk and inform your decision-making about breast cancer risk reduction and screening options for the earlier detection of breast cancer.
No tool can predict whether or not you will develop breast cancer. However, risk assessment tools can help you gain a more thorough understanding of what breast cancer
risk factors are and what they mean for your health.
These tools have strengths and limitations. Most importantly, no single tool takes all of the known breast cancer risk factors into account. This means that each tool can only provide an estimation of risk based on the risk factors it assesses.
As no single tool gives a complete and comprehensive assessment of breast cancer risk, think about the results alongside other sources of information. The Canadian Breast Cancer Foundation encourages you to consider having a conversation with a health care provider to help you understand your personal breast cancer risk, ways to reduce the risk, and your screening options to detect breast cancer earlier.
Using online risk assessment tools: Things to consider
Some online tools have been created to help the public learn more about breast cancer risk. You may have come across some of these tools on the Internet. A well-designed tool can provide you with an indication of your risk of developing breast cancer, based on the risk factors included in the tool.
If you use an online breast cancer risk assessment tool, please consider the following:
- Use a tool that has been developed by a credible and trustworthy source (e.g. a recognized research body, academic institution, health charity or government).
- The tool should provide you with information about how it was developed and its benefits and limitations, including what it can tell you about breast cancer risk and what it cannot tell you. Look for this information and read it before you use the tool. This can help you to better understand the tool and its results.
- Base your health decision-making on information from different, credible sources and consider using what you’ve learned to inform a conversation with a health care provider.
Risk assessment tools: At a glance
Gail Model – National Cancer Institute
The Gail model is used to estimate a woman’s risk of developing
invasive breast cancer over specific periods of time. Health care providers may use this model to assess breast cancer risk, inform decision-making about chemoprevention strategies, or to help determine eligibility for clinical trials.
How the tool works
The Gail model considers the following factors to assess breast cancer risk:
- Personal medical history, including the number of previous breast biopsies and the presence of atypical hyperplasia (a precancerous condition) in a previous biopsy
- Reproductive history (age at the start of menstruation and age at the first live birth of a child)
- Family history of breast cancer among first-degree relatives
Limitations
- The model considers limited information about family breast cancer history, which could underestimate risk
- It does not include several breast cancer-specific risk factors, such as personal history of breast cancer, use of hormone replacement therapy, breast density, breast feeding, or age at menopause
- It does not include lifestyle factors that may increase risk, such as smoking, alcohol consumption, diet or physical inactivity
Breast Cancer Risk Assessment Tool – National Cancer Institute
How the tool works
The tool estimates breast cancer risk based on the following risk factors:
- Age
- Age at first period
- Age at first live birth of a child
- Family history of breast cancer
- Personal history of breast cancer
- Number of past breast biopsies, including number of breast biopsies that showed atypical hyperplasia (a precancerous condition that increases breast cancer risk)
- Race/ethnicity
When you use the tool, its score provides an estimate of the average risk for a group of women with similar risk factors.
- For example, if the tool gives you a score of 1.7 per cent, this means that an estimated 1.7 per cent of women with similar risk factors will develop breast cancer in the next 5 years.
Limitations
See above for the Gail model’s limitations.
Tools to identify people at higher breast cancer risk
If you think you may be at a
higher risk of breast cancer, there are tools that cover a more comprehensive set of risk factors. They are used to help assess individual breast cancer risk and to inform decision-making about genetic counselling and testing.
IBIS Breast Cancer Risk Evaluation Tool
The
IBIS tool (also called the Tyrer-Cuzick model) is used to calculate a person’s likelihood of carrying the BRCA 1 or 2 mutations, which are associated with increased breast cancer risk. It estimates the likelihood of a woman developing breast cancer in 10 years and over the course of her lifetime. The tool is used to help inform a person’s decision-making about genetic counselling and testing.
How the tool works
The tool estimates breast cancer risk based on the following risk factors:
- Age
- Age at first live birth of a child
- Age at menopause
- Height and weight
- Use of hormone replacement therapy
- Comprehensive family history
RESULTS: Genetic counselling is advised when the model predicts a 10% or greater chance that the person has a mutation of the BRCA1, BRCA2, or both genes.
Limitations
- The tool does not include risk factors associated with lifestyle or breast density
Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA)
The
BOADICEA is a model used to calculate the risks of breast and ovarian cancer in women. It calculates the probability that a woman is a carrier of any cancer-associated mutations in the BRCA 1 or BRCA 2 gene. It also estimates the likelihood of a woman developing breast cancer in 5 years, and over the course of her lifetime. The tool is used to help inform a woman’s decision-making about genetic counselling and testing.
How the tool works
The tool estimates breast cancer risk based on:
- Family cancer history
- Genetic mutation status
RESULTS: A decision to go for genetic counselling is usually made when the model predicts a 10% or greater chance that the patient has a mutation of the BRCA1, BRCA2, or both genes.
Limitations
- The major limitation of this tool is that it only considers genetic mutation status and family history. It does not take any other breast cancer risk factors into account.
- The tool was developed using data for the United Kingdom. It may be applicable to populations in other high-income countries, however estimations of risk in other populations may be unreliable.
More information
Understanding breast cancer risk
Assessing personal risk
Genetic counselling and testing
Breast cancer risk factors