Paget's disease of the breast

Definition

Paget's disease of the breast is a rare type of breast cancer that is characterized by a red, scaly lesion on the nipple and surrounding tissue (areola).

Description

Paget's disease of the breast, also called mammary Paget's disease, is a rare breast condition that is often associated with underlying breast cancer. It is believed that Paget's disease of the breast occurs when invasive carcinoma or intraductal carcinoma (cancer of the milk ducts) spreads through the milk ducts to the nipple.

Although in most cases the underlying breast cancer is extensive, in 10% of the cases, cancer only affects the nipple and surrounding tissue. Rarely, there is no detectable underlying breast cancer. Paget's disease located elsewhere on the body (extramammary Paget's disease) is rarely associated with an underlying invasive cancer. This type of Paget's disease, most commonly found on and around the genitals, is believed to arise directly from the cells lining certain sweat gland ducts. Possibly, the few cases of mammary Paget's disease without an underlying breast cancer have a similar origin.

Paget's disease of the breast accounts for 2% of all breast cancers. On average, women are 62 years old and men are 69 years old at diagnosis. Breast cancer rarely occurs in men.

Causes and symptoms

The causes of Paget's disease of the breast are unknown. The most common signs and symptoms of Paget's disease include redness, scaling, and flaking on and around the nipple and areola. Other symptoms include itching, tingling, burning, oversensitivity, or pain. The lesion may bleed or weep and open sores (ulcers) may be present.

Diagnosis

A thorough breast examination would be performed. A breast mass can be felt (palpated) in about half of the women with Paget's disease. Mammography and ultrasonography should be conducted to look for cancer within the breast that cannot be felt.

The definitive diagnosis of Paget's disease is the presence of a certain cell type, called Paget's cells, in the skin of the nipple. A tissue sample may be easily obtained by touching a microscope slide to a weeping lesion or by scraping a scaly or crusted lesion gently with a microscope slide. Alternatively, a sample of the lesion may be obtained by cutting out a small piece of nipple tissue (biopsy). The biopsy would be performed with local anesthetic in the physician's office. If a mass was felt, a breast biopsy would be performed.

Treatments and prognosis

Treatments

The traditional treatment of Paget's disease of the breast is to surgically remove the breast (mastectomy). Conservative surgery, (nipple-areolar sacrificing lumpectomy) in which just the nipple, areola, and underlying tissue are removed, may be sufficient in some cases. The underarm (axillary) lymph nodes are rarely sampled or removed (lymphadenectomy), unless an underlying invasive cancer is a concern.

Radiation therapy may be used as adjuvant therapy to complement the surgical treatment, and if a lumpectomy is performed, radiation must be employed. Radiation therapy uses high-energy radiation from x rays and gamma rays to kill the cancer cells. The skin in the treated area may become red and dry, and fatigue is also a common side effect.

Chemotherapy, also used as adjuvant therapy if an underlying invasive breast cancer is found, uses drugs to kill the cancer cells. The side effects of chemotherapy include stomach upset, vomiting, appetite loss (anorexia), hair loss (alopecia), mouth or vaginal sores, fatigue, menstrual cycle changes, premature menopause, and low white blood cell counts with an increased risk of infection.

Prognosis

As with other breast cancers, the prognosis of Paget's disease depends on the extent of the cancer and whether it has spread to the lymph nodes and other organs.

Paget's disease alone

The survival rate of women with Paget's disease of the breast alone is 99.5%.

Paget's disease with invasive breast cancer

The prognosis for Paget's disease and invasive cancer is based on the stage of the underlying breast cancer. Staging for breast cancer is as follows:

• Stage 1-The cancer is no larger than 2 cm (0.8 in) and no cancer cells are found in the lymph nodes.

• Stage 2-The cancer is between 2 cm and 5 cm, and the cancer has spread to the lymph nodes.

• Stage 3A-Tumor is larger than 5 cm (2 in) or is smaller than 5 cm, but has spread to the lymph nodes, which have grown into each other.

• Stage 3B-Cancer has spread to tissues near the breast, (local invasion), or to lymph nodes inside the chest wall, along the breastbone.

• Stage 4-Cancer has spread to skin and lymph nodes beyond the axilla (regional lymph nodes) or to other organs of the body.

The prognosis depends on the type and stage of cancer. Over 80% of stage I patients are cured by current therapies. Stage II patients survive overall about 70% of the time, those with more extensive lymph nodal involvement doing worse than those with disease confined to the breast. About 40% of stage III patients survive five years, and about 20% of stage IV patients do so.

Alternative and complementary therapies

Although alternative and complementary therapies are used by many cancer patients, very few controlled studies on the effectiveness of such therapies exist. Mind-body techniques such as biofeedback, visualization, meditation, and yoga, have not shown any effect in reducing cancer but they can reduce stress and lessen some of the side effects of cancer treatments.

A few studies found an association between longer survival time and a diet high in beta-carotene and fruits. Acupuncture has been found to relieve chemotherapy-induced nausea and vomiting and reduce pain. In some studies, mistletoe has been shown to reduce tumor size, extend survival time, and enhance immune function. Other studies have failed to show a response to mistletoe treatment.

For more comprehensive information, the patient should consult the book on complementary and alternative medicine published by the American Cancer Society listed in the Resources section.

Prevention

There are no specific factors that increase a person's risk of developing Paget's disease. Men who are at an increased risk of developing breast cancer include those who have had radiation exposure and those with Klinefelter's syndrome. Women's risk factors for breast cancer include:

• a personal history of breast cancer

• a family history of breast cancer

• alterations in certain genes (e.g. BRCA1 and BRCA2)

• changes in breast tissue (e.g. lobular carcinoma in situ or atypical hyperplasia)

• long-term exposure to estrogen (e.g. early age at first menstruation or late menopause), and possibly use of hormone replacement therapy

• exposure to diethylstilbestrol (DES) before birth

• first pregnancy after 30 years of age

• alcohol consumption

Regularly scheduled screening mammograms are recommended for all women over the age of 40 years. Those with a significant family history (one or more first-degree relatives who have been treated for breast cancer), should start annual mammograms 10 years younger than the youngest relative was when she was diagnosed, but not earlier than 35. Monthly breast self examinations and yearly clinical breast examinations are recommended for all women. Daily exercise, totalling two to four hours a week, decreases a woman's risk of breast cancer by 50% to 75%. Women with a high risk of breast cancer may take the drug tamoxifen, which has been shown to reduce the occurrence (or recurrence) of breast cancer. Women at a very high risk may choose to have a mastectomy to prevent breast cancer (prophylactic mastectomy).

Special concerns

Of special concern to the young woman with breast cancer is the impact that treatment will have on her fertility and body image. Depression is common. There is ongoing research investigating whether timing breast cancer surgery to coincide with the luteal phase (after ovulation) of the menstrual cycle leads to an increased survival rate.

KEY TERMS

Areola

The darkened area that surrounds the nipple.

Diethylstilbestrol (DES)

A medication used between 1945 and 1970 to prevent miscarriage.

Extramammary Paget's disease

Paget's disease that is located anywhere on the body, excluding the breasts.

Luteal phase

That part of the menstrual cycle that begins after ovulation and ends at menstruation.

Mastectomy

Surgical removal of breast tissue. Mastectomy may be partial, when only some tissue is removed, or radical, when all breast tissue and adjacent tissues are removed.

QUESTIONS TO ASK THE DOCTOR
• What type of cancer do I have?

• What stage of cancer do I have?

• What is the five-year survival rate for women with this type and stage of cancer?

• Has the cancer spread?

• What are my treatment options?

• How much breast tissue will you be removing?

• Where will the scars be?

• What will my breast look like after surgery?

• When can I have breast reconstruction?

• What are the risks and side effects of these treatments?

• What medications can I take to relieve treatment side effects?

• Are there any clinical studies underway that would be appropriate for me?

• What effective alternative or complementary treatments are available for this type of cancer?

• How debilitating is the treatment? Will I be able to continue working?

• Are there any local support groups for breast cancer patients?

• What is the chance that the cancer will recur?

• Is there anything I can do to prevent recurrence?

• How often will I have follow-up examinations?