Deciding to have a breast screening mammogram (x-ray) is your choice.
To give your informed consent you'll need to understand:
- what breast screening can do
- what breast screening cannot do
- risks
What breast cancer screening can do
Breast cancer screening can show breast cancers at an early stage. This is when the cancers are too small for you or your GP to see or feel.
If breast cancer is found early, it’s easier to treat and there’s a better chance of recovery.
Research shows that women age 50 and over are at a higher risk of getting breast cancer.
What breast screening cannot do
The main limitations of breast screening are:
- it does not prevent breast cancer
- it may not help if you already have advanced stage breast cancer
- you can still develop cancer after your breast screening mammogram (interval cancer)
- inaccurate results
- overdiagnosis
Developing cancer after your breast screening mammogram
A negative (normal) breast screening mammogram result:
- means that there were no abnormalities found
- does not guarantee you are clear of breast cancer
You can develop breast cancer between breast screening mammograms.
This is known as interval cancer - because it is found in the time (interval) between your previous breast screening mammogram and your next breast screening mammogram.
Interval cancer can be a cancer that either:
- developed between your breast screening mammograms
- was there at your last breast screening mammogram but was not found - this type is rare
Interval cancers are not common. But they happen in every screening programme across the world.
For every 1,000 women in Ireland who have had a BreastCheck mammogram:
- 2 will develop breast cancer before their next breast screening mammogram
- 998 will not develop breast cancer before their next breast screening mammogram
This is why it is important to have the breast screening mammogram every 2 years and check your breasts regularly for signs of breast cancer.
Urgent advice: Contact your GP as soon as possible if:
- you have symptoms of breast cancer
Do this even if you have had a recent normal breast screening result.
False negative results
There is a small chance your breast screening mammogram result is negative but cancer is present.
This is known as a false negative result, and can happen in any screening programme across the world.
Around 2 out of every 1,000 women who have a breast screening mammogram will receive a false negative result.
False positive results
Around 3 in every 100 women who have a breast screening mammogram will receive a false positive result.
This is when your breast screening mammogram finds an abormality but you do not have cancer.
Risks
The main risks of breast screening are overdiagnosis, overtreatment and the radiation you are exposed to during a mammogram.
Overdiagnosis and overtreatment
Overdiagnosis is finding a breast cancer that would never cause trouble in your lifetime. Sometimes when breast cancer is found at an early stage it's not possible to tell if it is harmless or aggressive.
Overdiagnosis can lead to overtreatment. This is when harmless lesions are found and you get treatment, such as surgery, that you may not need.
Radiation
A mammogram is a breast x-ray. An x-ray is a type of radiation that can pass through the body and is turned into an image.
During the x-ray, your breasts are exposed to a very small amount of radiation. But this amount causes no significant risk to your health.
Having x-rays carries a risk of causing cancer many years or decades later. But this risk is very small.
For example, an x-ray of your chest, arms, legs or teeth has a 1 in 1 million chance of causing cancer.
If you have any concerns about the potential risks of having a mammogram, contact us.