Breast Cancer Health Article

Definition

Breast cancer is the abnormal growth and uncontrolled division of cells in the breast. Cancer cells can invade and destroy surrounding tissue, and may metastasize (spread) throughout the body via blood or lymph fluid to other parts of the body.

Description

Breast cancer is a leading cause of morbidity (illness) and mortality (death) for women. It is the second most common cause of cancer death among American women; every year, about 180,000 women are diagnosed with the disease.

Every woman is at risk for breast cancer. If a woman lives to age 85, there is one chance in nine that she will develop the condition sometime during the rest of her life. Age is an established risk factor; the risk of developing the disease increases with advancing age. The breast cancer risk of a 25-year-old woman is only one out of 19,608; by age 45, it is one in 93. More than 75% of all breast cancers are detected in women over age 50.

Causes and symptoms

There are a number of risk factors for the development of breast cancer, including:

• family history of breast cancer in first-degree relatives (mother, sister, or daughter)
• early onset of menstruation and late menopause
• reproductive history (women who never had children or have children late in life and women who have never breastfed have increased risk)
• history of abnormal breast biopsies

More than 75% of all breast cancers are diagnosed in women without a family history or other major risk factor for the disease. Inherited gene alterations also place women at risk for developing breast cancer at younger ages. About 20% of cases occur in families with a history of breast cancer. A breast cancer gene was discovered in 1994, however, only about 5% of breast cancers are believed to be related to the gene.

Some studies suggest that high fat diets, obesity, radiation exposure, or alcohol consumption contribute to the risk profile. Researchers have found that for certain women, hormone replacement therapy may contribute to the development of breast cancer. While one or more risk factors may boost a woman's chances of developing breast cancer, the interplay of factors is complex.

Not all lumps detected in the breast are malignant (cancerous). Many are benign and may be related to other breast diseases such as fibrocystic breast disease and require no treatment or simply the removal of the lump. All women should be taught to perform regular, monthly breast self-examinations (BSE) to detect any

changes in breast tissue. Health professionals should also encourage women to schedule a screening mammography, which is a breast x ray that will detect cysts or tumors too small to be found during self-examination.

Changes in the breast that may be a sign of breast cancer include:

• lump or thickening in breast or armpit
• changes in a nipple (thickening, pulling in, bleeding, or discharge)
• dimpled or reddened skin over the breast
• change in breast size or shape
• abnormality on a mammogram

Diagnosis

More than 90% of all breast cancers are detected by mammography. The American Cancer Society guidelines recommend screening mammograms every one to two years for women between 40 and 49, and every year after age 50. Women with a family history of breast cancer will be advised to have a mammogram every year at an earlier age.

Typically, mammography screening includes two views of each breast, one from above, and one from the side. Generally, the radiology technician examines the images immediately to make sure no further x rays are needed, or to decide whether an ultrasound may be required.

If an irregularity is detected, such as a mass, changes from earlier mammograms, abnormalities of the skin, or enlargement of the lymph nodes, further testing may be recommended. Diagnostic testing may include ultra- sound of the breast, a biopsy, or needle sampling, or consultation with a breast surgeon.

Biopsy of the breast is a removal of breast tissue for examination by a pathologist. An excisional biopsy is a surgical procedure in which the entire lump area and a margin of surrounding tissue are removed for examination. If the mass is very large, an incisional biopsy is performed to remove a portion of the suspicious area. Needle biopsy may be performed using two different methods. An aspiration needle biopsy uses a very fine needle to withdraw cells and fluid from the mass for analysis. A large core needle biopsy uses a larger diameter needle to remove small pieces of tissue from the mass that can be analyzed. These analyses determine whether the mass is benign or cancerous and whether further treatment is required.

To determine if the cancer has metastasized, physicians remove some axillary (underarm) lymph nodes to examine them for the presence of cancer cells. Lymph node dissection, the procedure that determines whether cancer cells are in the lymph nodes, is part of the process of staging (classifying the extent) the cancer. Breast cancer is rated from Stage 0 to Stage IV. The staging process uses an array diagnostic information to describe the extent of disease and includes:

• Stage 1: The cancer is no larger than 0.8 in (2 cm) and no cancer cells are found in the lymph nodes.
• Stage 2: The cancer is no larger than 0.8 in (2 cm) and has spread to the lymph nodes, or is larger than 0.8 in (2 cm), but has not spread to the lymph nodes.
• Stage 3A: The tumor is larger than 2 in (5 cm) and has spread to the lymph nodes, or is smaller than 2 in (5 cm), but has spread to the lymph nodes, which have blended together.
• Stage 3B: Cancer has spread to tissues near the breast or to internal mammary lymph nodes.
• Stage 4: Cancer has spread to skin and lymph nodes near the collarbone or to other organs of the body.