Second cancer: Breast cancer

What is breast cancer (as a second form of cancer)?

This page belongs to Second form of cancer. We recommend reading that information first.

The breasts consist mainly of fat and glands. In women, the glands produce milk after childbirth. Sometimes breast cells begin to divide uncontrollably and form a malignant tumor. This is called breast cancer. Breast cancer does not only occur in women, but occasionally also in men. The chance of developing breast cancer after childhood cancer is very small. You can do a number of things to reduce the risk of breast cancer, such as maintaining a healthy weight and drinking little or no alcohol.

Do I have an increased risk of breast cancer?

Everyone, including people who have not had cancer, can develop breast cancer. However, some cancer treatments can increase the risk.

The following treatments can increase the risk of breast cancer:

Female survivors who have been treated with:

• Radiation therapy ≥10 Gy at a volume that irradiates the breasts

• Radiation therapy to the upper abdomen that can extend above the diaphragm, likely affecting breast tissue at a young age

• ≥200 mg/m² doxorubicin

You can see in your treatment summary whether you received this radiation therapy. If you do not have a summary, you can contact the LATER clinic or the hospital where you were treated. Breast cancer is not always caused by treatment. Breast cancer is common, and the cause is usually unknown. A family history of breast cancer or ovarian cancer at a young age can increase your risk of breast cancer.

What are the symptoms and signs of breast cancer?

Certain symptoms and signs may indicate breast cancer. Even if you do not have these symptoms at the moment, it is important to recognize them.

The following symptoms and signs may indicate breast cancer:

• Small lump or area that feels different

• Changes in size or shape of one or both breasts

• Inverted nipple

• Changes to the nipple

• Fluid from the nipple

• Swelling in the armpit

• Changes to the skin of the breast

• Breast that feels warm

• Breast cancer usually does not cause pain

Rapid diagnosis and treatment of breast cancer are very important. If you recognize any of these symptoms or signs, contact your general practitioner immediately.

I have an increased risk of breast cancer. What tests are necessary and when?

For every woman, including women who have never had cancer, the recommendation is to regularly check your breasts yourself. If you notice changes or have doubts, go to your general practitioner.

If you have had radiation to the chest or upper abdomen, the recommendation is to have the following done annually from age 25 or from 8 years after the end of radiation until age 60:

• A mammogram

• An MRI scan of both breasts

Mammography

A mammogram is a special medical technique in which breast tissue is visualized using a low dose of X-ray radiation. This technique is also used in the population screening program for breast cancer. Small calcifications that are not visible on an MRI can be detected with this method.

MRI

Magnetic resonance imaging (MRI) is a technique that uses magnetic fields and computer technology to create detailed images of the breast. Contrast medium is usually administered during this procedure. Small abnormalities, especially in young women, can be detected with this method.

If breast and/or ovarian cancer occurs more frequently in your family, genetic testing can determine whether you have a hereditary predisposition.

What happens if I (might) have breast cancer?

If you (might) have breast cancer, your general practitioner or LATER physician will refer you to an oncology team. This team consists of:

• Breast surgeon

• Medical oncologist

• Radiation oncologist

The oncology team will conduct further tests and discuss treatment options with you if necessary.

What else can I do?

Living with an (increased risk of) breast cancer can be difficult. Talking with friends and family can help. Contact with people in a similar situation can also provide support, for example through a patient association such as VOX, part of the Dutch Childhood Cancer Association.

Above all, take good care of yourself. You can reduce the risk of breast cancer with a healthy lifestyle. It is especially important to maintain a healthy weight and drink little or no alcohol. Also take care of your mental health. Small changes can already have a positive impact on your physical and mental wellbeing.

It is important that you know you have an increased risk of breast cancer and that you recognize the symptoms and signs. If you have questions or are concerned, contact your general practitioner or LATER physician.

Where can I find more information?

This LATER website also contains information about:

• Healthy lifestyle

• Mental health

In the PanCare Plain Language Summaries you will find links to reliable information in English.

You can search for information about breast cancer online, but keep in mind that it is not always up-to-date and accurate.

Disclaimer

This information is based on the plain language summary of the guideline below, created by the PanCare Plain Information Group, and has been adapted to the Dutch LATER guideline where necessary. If you experience symptoms and signs, do not rely solely on this information, but consult your general practitioner, LATER physician, or specialist.

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