Paget disease and eczema are two conditions that can affect the skin of the breast. Although both may cause similar symptoms, they are very different. Paget disease is a rare type of breast cancer. Eczema is a common skin condition.

Paget disease only accounts for 0.5 to 5% of breast cancer cases. It causes skin changes such as itching, scaling, redness or discoloration, and a nipple discharge that is yellow or bloody.

Conversely, eczema affects more than 31 million people in the United States. It can occur on any area of the skin, causing redness or discoloration, itching, and patches of dry skin. There are different types of eczema, and the cause can vary from person to person.

This article covers the differences between Paget disease and eczema, including appearance, symptoms, and treatments.

Paget disease of the breast is a rare type of cancer. It typically affects only one breast, causing eczema-like changes to the skin of the nipple and areola.

Symptoms include:

  • itching or tingling
  • redness or discoloration
  • flaking, crusty, or thickened skin
  • nipple flattening
  • yellowish or bloody nipple discharge
  • a lump behind the nipple
  • an inverted or flattened nipple

Eczema, or dermatitis, may cause similar skin changes. However, it is not cancer and does not cause a lump under the skin. Symptoms include:

The key difference in appearance between the two conditions is that Paget disease only affects the nipple, while eczema rarely does.

Additionally, Paget disease usually affects one breast only, while eczema can affect both. Eczema can also affect other parts of the body.

It is important to note that Paget disease is rare. However, it is best for anyone who notices changes in the skin around the nipple or on the breast to contact their doctor as soon as possible rather than assume it is eczema or another skin condition.

Because Paget disease of the breast is a type of cancer, people with the condition who receive an earlier diagnosis are more likely to have a better outlook. If the person does not have it, a doctor will be able to identify the cause of the symptoms and recommend treatments to reduce them.

A doctor’s assessment typically begins with a review of the person’s medical history and a physical examination. They may inquire about symptoms, affected areas, any previous history of eczema, and any personal or family history of breast cancer.

During the physical exam, the doctor will look for changes to the skin of the nipple and feel for lumps. These findings may be enough for them to diagnose eczema.

However, some people with Paget disease of the breast receive an eczema diagnosis first, which then delays their treatment. For this reason, it is best for doctors to request further testing if they have any doubts about the diagnosis.

This may include:

  • a skin biopsy, which tests a small sample of skin for cancer, infection, or other changes
  • a breast biopsy, which tests a sample of tissue from deeper inside the breast
  • medical imaging, such as mammography, ultrasound, or MRI

Doctors are not sure what causes Paget disease of the breast. However, there are two theories.

The first theory is that a specific type of cancer cell, known as a Paget cell, breaks off from a tumor deeper inside the breast and travels through the milk duct, where it reaches the nipple. This enables cancer to affect the nipple and surrounding skin.

In 80–90% of cases, Paget disease occurs alongside other cancers, such as ductal carcinoma in situ or infiltrating ductal carcinoma, a type of invasive breast cancer. This would suggest a relationship between other cancers and Paget disease.

However, there are rare cases when people have Paget disease on its own. Because of this, some people believe that Paget disease is a separate, spontaneous process unrelated to other cancers.

A person’s genes and diet may affect their risk of developing Paget disease. Exposure to UV rays, certain chemicals, or radiation may also be contributing factors.

The most common form of eczema, atopic dermatitis, probably occurs due to a combination of factors that impair the skin barrier, making it less able to retain moisture. Because the skin is dry, it becomes reactive to substances or irritants, resulting in inflammation.

Some examples of potential triggers for eczema on the breasts include:

  • topical products, such as soaps, cosmetics, or fragrances
  • laundry detergents
  • rough fabrics
  • stress

Surgery is typically the first treatment for Paget disease. Depending on the size and location of the cancer, a surgeon may use a lumpectomy to remove growths or breast-conserving surgery, which removes the nipple and areola.

Alternatively, a mastectomy removes the entire breast in the case of larger or deeper growths. A doctor may recommend combining this with additional treatments, such as:

Health professionals may perform a lymph node biopsy to determine which treatment to use, as this can show whether the cancer has spread further.

The treatments above reduce the risk of breast cancer returning to the same site or developing in the other breast or elsewhere in the body.

Treatment for eczema focuses on controlling symptoms. Approaches a doctor recommends may vary depending on the cause. For example, if irritation from a skin care product is making symptoms worse, stopping using it may help.

Topical treatments can also help, such as:

  • using gentle soaps or cleansers when washing
  • applying topical corticosteroids to reduce inflammation
  • applying moisturizers and emollients to hydrate the skin

Learn more about remedies for eczema.

In addition to eczema, other conditions that can cause similar symptoms to Paget disease include:

Because of this, it is important not to try and self-diagnose rashes that appear on the breasts. A doctor can offer advice and treatments, if needed, for any new symptoms affecting the nipples or the skin on the breast.

Paget disease and eczema are both conditions that affect the skin of the breast and can cause similar symptoms. Doctors sometimes initially misdiagnose Paget disease of the breast as eczema.

Eczema is a common inflammatory skin condition that can range from mild to severe, while Paget disease is a rare form of cancer and can be life threatening. Their treatments vary significantly, as does the outlook for people with each condition.

Although Paget disease is rare, it is best for anyone who notices changes to the breast or nipple to seek medical advice as soon as possible to determine the cause.