This information is about a condition called Paget’s disease of the breast. It should ideally be read with our general information about breast cancer and ductal carcinoma in situ (DCIS).

Paget’s disease of the breast is an eczema-like change in the skin of the nipple, and 9 out of 10 women who have this have an underlying breast cancer. The underlying breast cancer may be an invasive breast cancer or ductal carcinoma in situ (DCIS). In DCIS, the cancer cells are completely contained within the milk ducts.

Around half of the women who have Paget’s disease will have a breast lump that can be felt at the time it is diagnosed.

Paget’s disease occurs in about 1–2 out of every 100 women with breast cancer. It usually occurs in women in their 50s, but can occur at an younger or older age.

It can affect men, but this is extremely rare. It usually first appears as a scaly, red rash affecting the nipple and sometimes the dark area of skin surrounding the nipple (the areola). The rash always affects the nipple first, and may then affect the areola. It does not go away and may become sore. The area may bleed slightly.

The cause of Paget's disease is unknown, but certain women seem to be at a higher risk of developing breast cancer. This includes women who have never had children, or had them late in life, women who started their periods at a young age or who had a late menopause, and women who have a strong family history of breast cancer.

The first symptom is usually an eczema-like rash, as described earlier. The skin of the nipple and areola may be red and inflamed. There may also be crusting, bleeding and ulceration. Some women have an itching or burning sensation. Fluid (discharge) may leak from the abnormal area of cells. The nipple may turn inwards (be inverted). There may or may not be a lump in the breast.

Paget’s disease can be confused with other skin conditions such as eczema, dermatitis or psoriasis, as they can look very similar. This can make Paget’s disease difficult to diagnose.

Paget’s disease usually first affects the nipple, and then the surrounding tissue. Other skin conditions usually affect the areola (the dark area of skin around the nipple) first, and then spread into the nipple.

Several tests may be carried out to diagnose Paget’s disease of the breast. They may include the following:

Mammogram (breast x-ray) Mammograms may be used to look for changes in the affected breast, and to check the other breast.

Ultrasound scan A gel is spread on the breast and a small device, which emits sound waves, is rubbed over the area. The echoes are converted into a picture of the breast tissue by a computer. This test is painless and takes just a few minutes.

Biopsy This is the main test for cancer cells below the skin surface. A small sample of skin and underlying breast tissue is taken and sent to the laboratory to be examined under a microscope. A local anaesthetic is usually given before the biopsy is carried out, to numb the area. The biopsy may be taken at the same time as an ultrasound, to ensure that it is taken from the abnormal area.

Imprint or scrape cytology Cells from the affected area can be scraped, or pressed, onto a glass slide to be examined under a microscope.

The treatment of Paget's disease of the breast will depend on:

• whether or not there is an underlying breast cancer
• whether it is DCIS or an invasive tumour
• how much of the breast is affected.

Surgery

Surgery is the main treatment for Paget’s disease. Removal of the breast (mastectomy) may be recommended, especially if the cancer is affecting a wide area (is extensive), is close to the nipple, or if there is DCIS in a number of areas in the breast (multi-focal). Some of the lymph nodes in the under-arm area may also be removed. If you have a mastectomy, it may be possible to have a breast reconstruction operation, either at the same time, or as a second operation some months later.

Surgery aimed at removing as little of the breast tissue as possible (breast-conserving therapy) may be possible if the cancer, or DCIS, is found to be close to the nipple and only affecting a small area of underlying tissue. This involves the removal of the nipple, areola, and an area of underlying normal tissue around it.

For some people, no further treatment will be needed after surgery. Others may need to have radiotherapy, hormonal therapy or chemotherapy. These may be used separately or together.

Radiotherapy

Radiotherapy treats cancer by using high‑energy x-rays to destroy the cancer cells, while doing as little harm as possible to the healthy cells. Radiotherapy to the remaining breast tissue is usually recommended after breast-conserving surgery.

Hormonal therapy

Hormonal therapies are commonly used for treating breast cancer. They reduce the production of hormones within the body, or prevent the hormones from stimulating the cancer cells to grow. Hormonal therapy is mainly used if the cancer is invasive, but may also be given to women who have DCIS. Tamoxifen and anastrozole (Arimidex®) are two commonly used hormonal treatments.

Chemotherapy

Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. It is not used to treat an underlying DCIS, but may be given if the cancer is invasive.

Trastuzumab (Herceptin®)

Herceptin is one of a new group of drugs called monoclonal antibodies.

Some breast cells divide and grow when a protein (human epidermal growth factor) attaches itself to another protein called HER2. Herceptin blocks this process by attaching itself to the HER2 protein so that the epidermal growth factor cannot reach the breast cancer cells.

Herceptin only works in people who have high levels of the HER2 protein, which you can be tested for.

It can be used to treat early breast cancer or breast cancer which has spread (secondary breast cancer).

Research into treatments for Paget’s disease of the breast is ongoing. Cancer doctors use clinical trials to assess new treatments. Before any trial is allowed to take place, an ethics committee must have approved it and agreed that the trial is in the interest of patients.

You may be asked to take part in a clinical trial. Your doctor must discuss the treatment with you so that you have a full understanding of the trial and what it involves. You may decide not to take part, or withdraw from a trial at any stage. You will then receive the best standard treatment available.

You may have many different emotions, including anger, resentment, guilt, anxiety and fear. These are all normal reactions, and are part of the process many people go through in trying to come to terms with their illness.

This section has been compiled using information from a number of reliable sources, including:

• Oxford Textbook of Oncology (2nd edition). Eds Souhami et al. Oxford University Press, 2002
• Cancer of the Breast (5th edition). Eds Donegan and Spratt, Saunders, 2002
• Cancer and Its Management (4th edition). Souhami and Tobias, Oxford Blackwell Scientific Publications, 2003.

For further references, please see the general bibliography.