Breast Cancer

The Breasts

Each breast has 15 to 20 overlapping sections called lobes. Within each lobe are many smaller lobule, which end in dozens of tiny bulbs that can produce milk. The lobes, lobules, and bulbs are all linked by thin tubes called duct. These ducts lead to the nipple in the center of a dark area of skin called the areola. Fat fills the spaces around the lobules and ducts. There are no muscles in the breast, but muscles lie under each breast and cover the ribs.

Each breast also contains blood vessels and vessels that carry colorless fluid called lymph. The lymph vessels lead to small bean-shaped organs called lymph node. Clusters of lymph nodes are found near the breast in the axilla (under the arm), above the collarbone, and in the chest. Lymph nodes are also found in many other parts of the body.

Types of Breast Cancer

The most common type of breast cancer begins in the lining of the ducts and is called ductal carcinoma. Another type, called lobular carcinoma, arises in the lobules.

When breast cancer spreads outside the breast, cancer cells are often found in the lymph nodes under the arm (axillary lymph nodes). If the cancer has reached these nodes, it may mean that cancer cells have spread to other parts of the body--other lymph nodes and other organs, such as the bones, liver, or lungs--via the lymphatic system or the bloodstream.

Cancer that spreads is the same disease and has the same name as the original (primary) cancer. When breast cancer spreads, it is called metastatic breast cancer, even though the secondary tumor is in another organ. Doctors sometimes call this distant disease.

Risk Factors for Breast Cancer

The risk of breast cancer increases gradually as a woman gets older. This disease is uncommon in women under the age of 35. All women age 40 and older are at risk for breast cancer. However, most breast cancers occur in women over the age of 50, and the risk is especially high for women over age 60.
Research has shown that the following conditions place a woman at increased risk for breast cancer:

• Personal history of breast cancer. Women who have had breast cancer face an increased risk of getting breast cancer again
• Genetic alterations. Changes in certain genes (BRCA1, BRCA2, and others) make women more susceptible to breast cancer. In families in which many women have had the disease, gene testing can show whether a woman has specific genetic changes known to increase the susceptibility to breast cancer. Doctors may suggest ways to try to delay or prevent breast cancer, or improve the detection of breast cancer in women who have the genetic alterations
• Family history. A woman's risk for developing breast cancer increases if her mother, sister, daughter, or two or more other close relatives, such as cousins, have a history of breast cancer, especially at a young age
• Certain breast changes. Having a diagnosis of atypical hyperplasia or lobular carcinoma in situ (LCIS) or having had two or more breast biopsy for other benign conditions may increase a woman's risk for developing cancer. Other factors associated with an increased risk for breast cancer include:
• Breast density. Women age 45 and older whose mammogram show at least 75 percent dense tissue are at increased risk. Dense breasts contain many glands and ligaments, which makes breast tumors difficult to see, and the dense tissue itself is associated with an increased chance of developing breast cancer
• Radiation therapy. Women whose breasts were exposed to radiation during their childhood, especially those who were treated with radiation for Hodgkin's disease, are at an increased risk for developing breast cancer throughout their lives. Studies show that the younger a woman was when she received her treatment, the higher her risk for developing breast cancer later in life.
• Late childbearing. Women who had their first child after the age of 30 have a greater chance of developing breast cancer than women who had their children at a younger age.

Also at a somewhat increased risk for developing breast cancer are women who started menstruating at an early age (before age 12), experienced menopause late (after age 55), never had children, or took hormone replacement therapy or birth control pills for long periods of time. Each of these factors increases the amount of time a woman's body is exposed to estrogens. The longer this exposure, the more likely she is to develop breast cancer.

In most cases, doctors cannot explain why a woman develops breast cancer. Studies show that most women who develop breast cancer have none of the risk factors listed above, other than the risk that comes with growing older. Also, most women with known risk factors do not get breast cancer. Scientists are conducting research into the causes of breast cancer to learn more about risk factors and ways of preventing this disease.

Early Detection

When breast cancer is found and treated early, the chances for survival are better. Women can take an active part in the early detection of breast cancer by having regular screening mammograms and clinical breast exams (breast exams performed by health professionals). Some women also perform breast self-exams.

A screening mammogram is the best tool available for finding breast cancer early, before symptoms appear. A mammogram is a special kind of x-ray. It is different from a chest x-ray or x-rays of other parts of the body. Screening mammograms are used to look for breast changes in women who have no signs of breast cancer.

Mammograms can often detect breast cancer before it can be felt. Also, a mammogram can show small deposits of calcium in the breast. Although most calcium deposits are benign, a cluster of very tiny specks of calcium (called microcalcifications) may be an early sign of cancer.

Although mammograms are the best way to find breast cancer early, they do have some limitations. A mammogram may miss some cancers that are present (false negative) or may find things that turn out not to be cancer (false positive). And detecting a tumor early does not guarantee that a woman's life will be saved. Some fast-growing cancers may already have spread to other parts of the body before being detected.

Still, regularly scheduled screening mammograms, together with clinical breast exams, offer the best chance of finding and treating breast cancer early. Studies show that mammograms reduce the risk of dying from breast cancer. The National Cancer Institute recommends that women in their forties and older have mammograms on a regular basis, every 1 to 2 years.

Women should talk with their doctor about factors that can increase the risk for breast cancer. Women of any age who are at higher risk for this disease should ask their doctor when to begin and how often to have screening mammograms and breast exams.

Some women perform monthly breast self-exams to check for any changes in their breasts. When doing a breast self-exam, it's important to remember that each woman's breasts are different, and that changes can occur because of aging, the menstrual cycle, pregnancy, menopause, or taking birth control pills or other hormones. It is normal for the breasts to feel a little lumpy and uneven. Also, it is common for a woman's breasts to be swollen and tender right before or during her menstrual period. Remember that for women in their forties and older, a monthly breast self-exam is not a substitute for regularly scheduled screening mammograms and clinical breast exams by a health professional.

Symptoms

Early breast cancer usually does not cause pain. In fact, when breast cancer first develops, there may be no symptoms at all. But as the cancer grows, it can cause changes that women should watch for:

• A lump or thickening in or near the breast or in the underarm area;
• A change in the size or shape of the breast;
• Nipple discharge or tenderness, or the nipple pulled back (inversion) into the breast;
• Ridges or pitting of the breast (the skin looks like the skin of an orange; or
• A change in the way the skin of the breast, areola, or nipple looks or feels (for example, warm, swollen, red, or scaly).

A woman should see her doctor about any symptoms like these. Most often, they are not cancer, but it's important to check with the doctor so that any problems can be diagnosed and treated as early as possible.

Diagnosis

An abnormal area on a mammogram, a lump, or other changes in the breast can be caused by cancer or by other, less serious problems. To find out the cause of any of these signs or symptoms, a woman's doctor does a careful physical exam and asks about her personal and family medical history. In addition to checking general signs of health, the doctor may do one or more of the breast exams described on the following page.

• Palpation. The doctor can tell a lot about a lump (its size, its texture, and whether it moves easily) by palpation, carefully feeling the lump and the tissue around it. Benign lumps often feel different from cancerous ones.
• Mammography. X-rays of the breast can give the doctor important information about a breast lump. If an area on the mammogram looks suspicious or is not clear, additional mammograms may be needed.
• Ultrasonography. Using high-frequency sound waves, ultrasonography can often show whether a lump is solid or filled with fluid. This exam may be used along with mammography.

Based on these exams, the doctor may decide that no further tests are needed and no treatment is necessary. (In such cases, the doctor may need to check the woman regularly to watch for any changes.)

Often, however, fluid or tissue must be removed from the breast to make a diagnosis. A woman's doctor may refer her for further evaluation to a surgeon or other health care professional who has experience with breast diseases. These doctors may perform:

• Fine needle aspiration. A thin needle is used to remove fluid from a breast lump. This procedure may show whether a lump is a fluid-filled cyst (not cancer) or a solid mass (which may or may not be cancer). Clear fluid removed from a cyst may not need to be checked by a lab.
• Needle biopsy. Using special techniques, tissue can be removed with a needle from an area that is suspicious on a mammogram but cannot be felt. Tissue removed in a needle biopsy goes to a lab to be checked by a pathologist for cancer cells.
• Surgical biopsy. The surgeon cuts out part or all of a lump or suspicious area. A pathologist examines the tissue under a microscope to check for cancer cells.

When a woman needs a biopsy, these are some questions she may want to ask her doctor:

• What type of biopsy will I have? Why?
• How long will it take? Will I be awake? Will it hurt?
• How soon will I know the results? ? If I do have cancer, who will talk with me about treatment? When?

When Cancer Is Found

When cancer is found, the pathologist can tell what kind of cancer it is (whether it began in a duct or a lobule) and whether it is invasive cancer (has invaded nearby tissues in the breast).

Special lab tests of the tissue help the doctor learn more about the cancer. For example, hormone receptor test (estrogen and progesterone receptor tests) can help predict whether the cancer is sensitive to hormones. Positive test results mean hormones help the cancer grow, and the cancer is likely to respond to hormonal therapy. Other lab tests are sometimes done to help the doctor predict whether the cancer is likely to grow slowly or quickly. The doctor may order x-rays and blood tests. The doctor may also do special exams of the bones, liver, or lungs because breast cancer may spread to these areas.

If the diagnosis is cancer, the patient may want to ask these questions:

• What kind of breast cancer do I have? Is it invasive?
• What did the hormone receptor test show? What other lab tests were done on the tumor tissue, and what did they show?
• How will this information help in deciding what type of treatment or further tests to recommend?

The patient's doctor may refer her to other doctors who specialize in treating cancer, or she may ask for a referral. Treatment generally begins within a few weeks after the diagnosis. There will be time for the woman to talk with the doctor about her treatment choices, to get a second opinion, and to prepare herself and her loved ones.

Back to Top