Paget's disease of the breast

Paget's disease of the breast (also known as Paget's disease of the nipple ) is a malignant condition that outwardly may have the appearance of eczema, with skin changes involving the nipple of the breast.

The condition occurs when Paget's cells, which are large and irregular, form in the skin of the nipple. Although Paget believed the cells were not cancerous, it was later proved that the cells were themselves malignant, in addition to indicating another underlying breast cancer. Since the condition in itself is often innocuous and limited to a surface appearance, it is sometimes dismissed, although actually indicative of a very serious underlying condition, breast cancer.

Extramammary Paget's disease (EMPD) has the same histologic features as Paget's disease of the breast but different locations.

Symptoms


On average, a woman may experience signs and symptoms for six to eight months before a diagnosis is made.

Paget's disease's symptoms may vary based on the stage of the disease. However, the main symptoms that can occur in Paget's disease include flaky or scaly skin on the nipple, straw-colored or bloody nipple discharge, skin and nipple changes in only one breast or the flattened nipples. Patients may also experience crusty, oozing or hardened skin resembling eczema, on the nipple, areola or both and fluctuating skin changes early on, making it appear as if the skin is healing on its own. Some patients complain of burning sensations on the nipples or breasts. These symptoms usually occur in more advanced stages, when serious destruction of the skin often prompts the patient to consult. Lumps or masses in the breast occur in 50% of the patients. In more advanced stages, the disease may cause tingling, increased sensitivity and pain.

The first symptom is usually an eczema-like rash, usually only affecting one nipple. The skin of the nipple and areola may be red, itchy and inflamed. 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, and there may be redness, oozing and crusting, and a sore that does not heal.

The symptoms usually affect the nipple and then spread to the areola and then the breast. It is common for the symptoms to disappear for a while, which may make the patient think incorrectly that the condition has cleared up spontaneously.

Most women do not visit the doctor because they take Paget's disease to be minor contact dermatitis or eczema. A lump or skin irritation that does not seem to heal for over a month indicates that attention by a specialist is needed.

Diagnosis
Recommended tests are a mammogram and a biopsy to confirm the diagnosis, and cytopathology may also be helpful.

Paget's disease is difficult to diagnose due to its resemblance to dermatitis and eczema. Eczema tends to affect the areola first and then the nipple whereas paget's spreads from the nipple.

During a physical examination the doctor examines the unusual areas of the breast, especially the appearance of the skin on and around the nipples and feeling for any lumps or areas of thickening.

The most common test used to diagnose Paget's disease is the biopsy, removal of a tissue sample from the affected area which is then examined under the microscope by a pathologist, who distinguishes Paget cells from other cell types by staining tissues to identify specific cells (immunohistochemistry).

Samples of nipple discharge may also be examined under the microscope to determine whether Paget cells are present.

Imprint or scrape cytopathology may be useful: scraping cells from the affected area, or pressing them onto a glass slide to be examined under the microscope.

Treatment
Paget's disease of the breast is a type of cancer of the breast. Treatment usually involves a lumpectomy or mastectomy to surgically remove the tumour. Chemotherapy and/or radiotherapy may be necessary.

Paget's disease is mainly treated with surgery. However, the specific treatment often depends on the characteristics of the underlying breast cancer.

Invasive cancer or extensive ductal carcinoma in situ is primarily treated with modified radical mastectomies. The procedure consists in the removal of the breast, the lining over the chest muscles and a part of the lymph nodes from under the arm. In cases of non-invasive cancers, simple mastectomies are performed in which only the breast with the lining over the chest muscles are removed.

Patients suffering from cancer that has not spread beyond the nipple and the surrounding area are often treated with breast-conserving surgery or lumpectomy. They usually undergo radiation therapy after the actual procedure to prevent recurrence. A breast-conserving surgery consists in the removal of the nipple, areola and the part of the breast that is affected by cancer.

In most cases, adjuvant treatment is part of the treatment schema. This type of treatment is normally given to patients with cancer to prevent a potential recurrence of the disease. Whether adjuvant therapy is needed is considered upon the type of cancer and if the cancer cells have spread to the lymph nodes. In Paget's disease, the most common type of adjuvant therapy is radiation following breast-conservative surgery.

Adjuvant therapy may also consist of anticancer drugs or hormone therapies. Hormonal therapy reduces the production of hormones within the body, or prevent the hormones from stimulating the cancer cells to grow and it is commonly used in cases of invasive cancer by the mean of drugs such as tamoxifen and anastrozole.

Research into treatments for Paget's disease of the breast is ongoing. Cancer doctors use clinical trials to assess new treatments.

Prognosis
If lymph nodes are negative, the five year and ten year survival is 85% and 79% respectively. If the lymph nodes are positive, it is 32% and 28%. Involvement of the lymph nodes do not directly cause any harm but it is a merely an indicator of systemic spread.

Furthermore, patients with an identifiable associated underlying breast tumor have a survival rate of 38-40% at 5 years and a survival rate of 22-33% at 10 years. The death rate of metastatic breast carcinoma in patients with mammary Paget's disease and underlying cancer is 61.3%, with a 10-year cumulative survival rate of 33%.

Epidemiology
Most patients diagnosed with Paget's disease of the nipple are over age 50, but rare cases have been diagnosed in patients in their 20s. The average age at diagnosis is 62 for women and 69 for men. The disease is rare among both women and men.

History
The condition is named after Sir James Paget, an English surgeon who first described it in 1875. Several other diseases are also named after Paget.