What is Breast Cancer

Breast cancer starts in the breast tissue. It occurs when abnormal cells in the breast tissue multiply and form a tumour that may spread.

Most cases are found in people age 50 and over.

There are 2 ways to describe breast cancer:

• Invasive breast cancers extend beyond the wall of the milk duct and into the surrounding tissues.
• Non-invasive breast cancers do not extend beyond the wall of the milk duct into the surrounding breast tissues.

To learn more about breast cancer, visit the Canadian Cancer Society

Breast Cancer Screening

The goal of breast cancer screening is to detect cancer early and provide treatment. Mammography is currently the recommended test used to detect breast cancer.

It is important to find breast cancer early because:

• There is a better chance of treating the cancer successfully
• It is less likely to spread
• There may be more treatment options
• When breast cancer is caught early, 90% of people fully recover after treatment

Overview: Ontario Breast Screening Program (OBSP)

First established in 1990, the Ontario Breast Screening Program (OBSP) provides high quality breast cancer screening services to women, Two-Spirit, trans and nonbinary people living in Ontario. It is operated by Cancer Care Ontario and funded by the Ontario Ministry of Health and Long-Term Care.

Who Should Get Screened

The OBSP currently accepts women who fall into the following categories

If you are 30 to 69 years old and confirmed high risk:

The Ontario Breast Screening Program (OBSP) recommends getting a mammogram with an MRI (a test that uses radio waves and a magnetic field to create different images of the breast) or ultrasound (a test that uses sound waves to create images of the breast) every year.

High-risk status is based on a family or medical history of breast cancer and must be confirmed by a doctor or genetic counsellor. Breast cancer testing for eligible people at high risk is covered by OHIP.

Talk with your doctor or nurse practitioner if you think you have family or medical history related to breast cancer or other criteria that may place you at high risk.

If you are 40 to 49 years old:

As of October 8, 2024, you can self-refer for mammograms beginning at age 40. You will not need a doctor or nurse practitioner’s referral and the service is covered by OHIP.

Talk to your doctor, nurse practitioner or call Health811 to have a conversation about your risk of cancer, the potential benefits and risks of breast cancer screening and your preferences and values for screening to determine if it is right for you. You can also go to myCANCERiQ to complete a cancer risk assessment.

You will be able to book an appointment by contacting your nearest Ontario Breast Screening Program location or call 1-800-668-9304. You cannot book an appointment until fall 2024.

If you are 50 to 74 years old:

The Ontario Breast Screening Program recommends getting a mammogram every 2 years. You don’t need a doctor or nurse practitioner's referral and the service is covered by OHIP.

To book an appointment, contact your nearest Ontario Breast Screening Program location or call 1-800-668-9304

If you are over 74 years old:

Speak with your doctor or nurse practitioner about getting tested for breast cancer

If you choose to get tested, you will need a referral for a mammogram from your doctor or nurse practitioner. This service is covered by OHIP with a referral.

How to get a mammogram

All physicians and nurse practitioners in our Family Health Team are members of the OBSP.

• When you go for your first mammogram, you will automatically be entered as part of the OBSP. You will receive reminder letters for your screening from the program, and copies of your test results are sent to your family doctor to review.
• People aged 40 and over who are at average risk may refer themselves to the OBSP. To self-refer, please by contacting your nearest Ontario Breast Screening Program location or call 1-800-668-9304 to make an appointment.
• People between the ages of 30 to 69 who are at high risk will need a referral from their doctor or nurse practitioner to be screened at an OBSP centre.

Online Resources

Breast cancer testing and screening (Ontario Ministry of Health) 

myCANCERiQ

Cancer Care Ontario - Breast Cancer Screening for People Ages 40 to 49

Ontario Health Wait Times

Edited October 2024