The disease is named after Sir James Paget who first reported the link between changes in the nipple and underlying breast cancer.
Most cases of Paget's disease are found in menopausal women, but it can also appear in women as young as 20, although this is rare.
This article looks at the causes, symptoms, diagnosis, and treatment of Paget's disease.
Contents of this article:
What is Paget's disease of the breast?
Paget's disease indicates a 90 percent chance of an underlying breast cancer.
Paget's disease indicates underlying breast cancer, either ductal carcinoma in situ (DCIS), or invasive breast cancer.
It was initially believed that the affected cells were not cancerous, but it was later proven that Paget's cells were indeed malignant.
The symptoms of Paget's disease can be mistaken for an innocuous skin condition and as a result it is sometimes dismissed and diagnosis is delayed. However, the condition indicates the presence of a breast cancer that may prove fatal if left untreated.
Most patients diagnosed with the disease are over the age of 50, but rare cases have been diagnosed in people in their 20s. The average age at diagnosis is 62 for women and 69 for men. However, the disease is rare in both sexes.
Symptoms of Paget's disease of the breast
On average, a woman may experience signs and symptoms for 6-8 months before a diagnosis is made. Symptoms of Paget's disease vary depending on the stage of development. They usually only occur in one breast.
The main symptoms include:
- flaky or scaly skin on the nipple that does not heal over time
- straw-colored or bloody nipple discharge
- flattened or inverted nipples
The earliest symptom of Paget's disease is often an eczema-like rash, usually affecting only one nipple. The skin of the nipple and the dark skin around it (areola) may become red, itchy, and inflamed. Some women have an itching or burning sensation.
Other symptoms can include:
- fluid discharge from the abnormal area of cells
- there may or may be not be a lump in the breast
- there can be redness, oozing, and crusting
- there may be a sore that does not heal
The symptoms usually affect the nipple initially, then spread to the areola, and finally the breast. It is common for the symptoms to disappear temporarily, which may falsely lead an individual to believe that the condition has resolved.
Paget's disease vs. eczema
Paget's disease may sometimes be mistaken for eczema.
Paget's disease is difficult to diagnose due to its resemblance to dermatitis and eczema. The latter, unlike Paget's disease, usually affects the areola first and then the nipple.
Most women do not visit the doctor because they mistake the condition for contact dermatitis or eczema. Women who feel a lump or notice skin irritation that does not heal for over a month are advised to seek the opinion of a specialist.
A person may also experience crusty, oozing, or hardened skin resembling eczema on the nipple, areola, or both. The skin changes may fluctuate early on, making it appear as if the skin is healing on its own.
Some patients complain of burning sensations in the nipples or breasts. These symptoms usually occur in more advanced stages, when serious destruction of the skin often prompts them to visit a doctor.
Lumps or masses in the breast may occur in up to 50 percent of people. In more advanced stages the disease may cause tingling, increased sensitivity, and pain.
Causes of Paget's disease of the breast
The exact cause of Paget's disease of the breast is unknown. However, there are two theories. The leading theory is that there is already a cancer of the breast, and some of these cells migrate through the milk ducts to the surface of the nipple.
Another theory is that the skin cells of the nipple spontaneously transform into cancer cells. In a few cases of Paget's disease, there is no underlying breast cancer, or if a tumor is present, it is unrelated to the disease in the nipple.
Risk factors for Paget's disease
The risk factors for developing Paget's disease are similar to those for other types of breast cancer and include:
- age - the risk increases as we age
- previous personal history of breast cancer or breast abnormalities
- relatives with breast cancer
- denser breast tissue
- being overweight or obese
- hormone replacement therapy
- excessive alcohol consumption
Diagnosing Paget's disease of the breast
One of the most common methods of diagnosing Paget's disease of the breast is a mammogram.
Recommended tests are a mammogram and a biopsy to confirm the diagnosis.
During a physical examination, the doctor examines the unusual areas of the breast, especially the skin on and around the nipples and feels for any lumps or areas of thickening.
A biopsy is the most commonly used test to diagnose Paget's disease. A biopsy involves removing a tissue sample from the affected area and examining it under a microscope. There are a number of different biopsy techniques. These include:
- a surface biopsy - gently scraping cells from the skin surface
- a shave biopsy - shaving off the top layer of skin
- a punch biopsy - removing a small disc of skin with a circular tool
- a wedge biopsy - removing a small wedge of skin with a scalpel
A pathologist may use a technique called immunohistochemistry, which involves staining tissues to identify specific cells. It helps to differentiate Paget's disease cells from other cell types.
Samples of nipple discharge may also be examined under the microscope to check if Paget cells are present.
Another technique is called Imprint or scrape cytology. This involves scraping cells from the affected area, or pressing them onto a glass slide to be examined under the microscope.
Treatment options for Paget's disease of the breast
Surgery is the most common treatment for Paget's disease of the breast. The specific treatment depends on the characteristics of the underlying breast cancer.
A modified radical mastectomy may be recommended when invasive cancer or ductal carcinoma in situ (DCIS) has been diagnosed. In this operation, a surgeon removes the breast, the lining over the chest muscles, and some of the lymph nodes under the arm.
In cases where underlying breast cancer is not invasive, the surgeon may perform a simple mastectomy to remove only the breast and the lining over the chest muscles.
Alternatively, patients whose disease is confined to the nipple and the surrounding area may undergo breast-conserving surgery or lumpectomy followed by radiation therapy. During breast-conserving surgery, a surgeon removes the nipple, areola, and the entire portion of the breast believed to contain the cancerous cells. In most cases, radiation therapy is also used to help prevent the cancer from returning.
Preventing Paget's disease of the breast
Paget's disease of the breast cannot be prevented. However, one may prevent complications, such as osteoarthritis, by taking certain medications, maintaining a healthy weight, and regularly exercising.