Breasts are mainly made of fat and glands. In females, these glands produce milk after birth.
Sometimes, the cells that make up the breasts become malignant. This means that they do not work properly any more and multiply uncontrollably, causing a tumour to grow. When this happens, this is called breast cancer. Breast cancer can also occur in men, although it is extremely rare.
Due to treatment of the first cancer, survivors sometimes have a higher risk of breast cancer. There are a number of things anyone can do that may lower the risk of having breast cancer, such as reaching or maintaining a healthy weight and to avoiding drinking (too much) alcohol.
Am I at higher risk of breast cancer?
Anyone, including people who have never had cancer treatment, may develop breast cancer. However, there are some cancer treatments that may increase the risk of having breast cancer as a subsequent tumour later in life.
The following treatment can increase the risk of breast cancer:
Radiotherapy (10 Gy or more) to the chest or upper abdomen, when the breast area is included
You can find out if you had any of these treatments by looking at your treatment summary. If you do not have a treatment summary or if you have any questions, do contact your treating hospital.
If you develop breast cancer, it does not always mean that this is caused by treatment for your first cancer. Breast cancer is common and for most women the cause is unknown. However, adopting or maintaining a healthy lifestyle can lower the risk of developing breast cancer. For more information on taking up a healthier lifestyle, please read: Health promotion. If breast cancer or ovarian cancer at an unusually young age is common in your family, this may also increase your risk of having breast cancer.
What are the symptoms and signs of breast cancer?
There are symptoms and signs that can tell you if you might have breast cancer. You might not have these symptoms and signs at the moment, but it is important to be aware of them in case they may develop in the future.
Symptoms and signs of breast cancer are:
A new lump, bump or thick area in one of the breasts that was not there before.
Changes in size or shape of one or both breasts.
Changes in the appearance or position of one or both nipples.
Changes in the appearance of the skin on or around the nipple(s). Sometimes the skin becomes scaly, crusty, red, hot or itchy.
Fluid leaking from one or both nipples.
A lump or swelling in one or both armpits.
Breast cancer usually does not cause any pain in the breast(s).
Early diagnosis and treatment of breast cancer is very important. If you experience any of these symptoms or signs, please contact your general practitioner or follow-up care specialist soon.
I am at higher risk of breast cancer. What tests should I have and when?
Anyone, including people who have never had cancer treatment, is advised to inspect their breasts regularly. It is important that whenever you notice changes in your breast (see figure) or when you are in doubt, that you discuss this with your general practitioner or follow-up care specialist.
If you received radiotherapy to the chest or upper abdomen and, therefore, are at higher risk of breast cancer, it is advised to have the following tests every year after the age of 25 or 8 years after radiation treatment ended, whichever occurs last. It is advised to continue testing at least until the age of 60 years:
Have a mammogram and MRI scan of the breasts done. A mammogram and MRI scan are both diagnostic tests that can visualise the breasts.
Having a mammogram or an MRI both have their advantages and disadvantages, for example:
Having a mammogram to test for breast cancer:
Mammograms have a good track record of detecting breast cancer.
Having a mammogram may help to identify the disease in an early stage. This could help treat the tumour more easily.
A mammogram is a relatively inexpensive test to perform and should be covered by most national health service programs and insurance plans.
If you do not develop breast cancer, having a mammogram could make you feel reassured that you do not have breast cancer.
A mammogram can cause anxiety when you are waiting for test results.
You may experience pain during the mammogram due to the pressure on your breasts.
You will be exposed to a small amount of radiation during the mammogram. For example, in a woman treated with moderate to high dose chest radiation for a childhood cancer, the additional radiation exposure that would result from 50 mammograms (annual mammogram from age 25 to 74) is less than 1% of the total amount.
Mammograms may not be as accurate for breast cancer screening in young women with dense breast tissue. Dense breast tissue means that there is less fatty tissue and more dense tissue including milk glands, milk ducts and supportive tissue, which is more common in younger women.
Having a MRI to test for breast cancer:
Breast MRI is more accurate in detecting a hidden breast cancer in young women with dense breast tissue
For some people, especially when claustrophobic, having an MRI scan can be stressful. Imaging professionals should be able to help with positioning to minimise discomfort.
You may not be able to have a breast MRI if you have any medical devices or metal hardware in your body or if you have a MRI contrast allergy. However, many modern devices are MRI compatible.
You may need to have the breast MRI performed during a specific time in your menstrual cycle.
If you have poor kidney function, an MRI with gadolinium contrast may place you at risk of kidney damage (a syndrome called nephrogenic systemic fibrosis).
An MRI scan can be costly and may not be covered by your health insurance.
If breast and/or ovarian cancer runs in your family and you are worried that you may get it too, please inform your general practitioner or follow-up care specialist. If you want, they may request a genetic test that can tell if you have inherited one of the breast and/or ovarian cancer genes.
What happens if I (might) have breast cancer?
If you (might) have breast cancer, your general practitioner or follow-up care specialist will refer you to an oncology team. This team may include, but is not limited to:
Breast surgeon (surgeon specialised in breasts)
Medical oncologist (physician specialised in cancer)
Radiation oncologist (physician specialised in treating cancer with radiotherapy)
The specialist may discuss different treatment options with you.
What else can I do?
Knowing that you may be at increased risk of subsequent cancer can be difficult. Talking to friends and family can be helpful as well as specialist counselling and/or contact with support groups, such as patient organisations. For more information on taking care of your mental health, please read: Mental health problems.
To lower your risk of breast cancer, adopting or maintaining a healthy lifestyle is extremely important. In particular, it is important to reach or maintain a healthy weight and to avoid drinking (too much) alcohol. Taking care of your mental health may be beneficial; even small changes to your lifestyle can have a positive impact on both your physical and mental health. For more information on taking up a healthier lifestyle, please read: Health promotion.
It is important that you are aware of the possibility of developing breast cancer and that you know the symptoms and signs. If you have any further questions or the information in this brochure concerns you, please contact your general practitioner or follow-up care specialist.
Where can I find more information?
You may find more information about breast cancer online. However, it is important to be aware that this information is not always up to date or accurate.
Some sources of further information are:
CoppaFeel!: Here you can find more information about breast cancer and instructions for self-testing
On this website, you can also find more information related to this topic:
While the PanCare PLAIN information group strives to provide accurate and complete information that is up-to-date as of the date of publication, you can check with your general practitioner or follow-up care specialist if this summary reflects the most up-to-date information available and whether it is relevant for you.
Please do not rely solely on this information. It is best to also seek the advice of a qualified medical practitioner if you have questions regarding a specific medical condition, disease, diagnosis or symptom.
No warranty or representation, expressed or implied, is made concerning the accuracy, reliability, completeness, relevance, or timeliness of this information. PanCare has produced the English version and PanCare is not responsible for the translated versions of this summary.
 Mulder, R.L. et al. (2020) Updated Breast Cancer Surveillance Recommendations for Female Survivors of Childhood, Adolescent, and Young Adult Cancer From the International Guideline Harmonization Group. Available at: https://ascopubs.org/doi/10.1200/JCO.20.00562