Breast Cancer Screening for People at High Risk
The Ontario Breast Screening Program (OBSP) screens women, trans and nonbinary people ages 30 to 69 who meet the High Risk OBSP eligibility criteria once a year with mammography and breast magnetic resonance imaging (MRI) or screening breast ultrasound if breast MRI is not medically appropriate.
Who is Eligible?
People ages 30 to 69 can get screened through the High Risk OBSP if they have a referral from their primary care provider, a valid Ontario Health Insurance Plan number, no breast cancer symptoms and meet criteria listed in Category A or B.
Category A – Eligible for direct entry into the High Risk OBSP based on personal and family history. To fall under this category, at least one of the following criteria must be met:
- Known carrier of a pathogenic or likely pathogenic gene variant (e.g., BRCA1, BRCA2, TP53, PALB2) that increases their risk for breast cancer
- Have not had genetic testing, but have had genetic counselling because they are a first-degree relative of a carrier of a pathogenic or likely pathogenic variant (e.g., BRCA1, BRCA2, TP53, PALB2) that increases their risk for breast cancer
- Previously assessed by a genetics clinic (using the IBIS or CanRisk risk assessment tools) as having a 25% or greater lifetime risk for breast cancer based on personal and family history
- Have had radiation therapy to the chest to treat another cancer (e.g., Hodgkin lymphoma) before age 30 and at least eight years ago
Category B – Genetic assessment required (i.e., counselling and/or testing) to determine eligibility for the High Risk OBSP. To fall under this category, at least one of the following criteria must be met:
- An identified pathogenic or likely pathogenic gene variant that is associated with breast cancer risk (e.g., BRCA1, BRCA2, TP53, PALB2) in a close blood relative
- A personal or family history of a cancer suggestive of a hereditary breast cancer syndrome
People with a personal history of breast cancer and/or breast implants may get screened through the High Risk OBSP if they meet program eligibility criteria.
The High Risk OBSP does not accept new participants over age 70. However, when participants already in the High Risk OBSP turn 70, the program will continue to screen them with mammography only every year until they are age 74.
High Risk OBSP sites do not send letters to people over age 74 about participating in the program. To continue screening through the High Risk OBSP, a referral is required from a primary care provider.