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Breast Cancer

What is breast cancer and why does it happen?

Breast cancer is the second most common cancer in women, and is found in one in eight women in the United States. It is a group of diseases in which cells in the tissues of the breast become abnormal and divide without order or control. These malignant cells form too much tissue and become a tumor. The tumor can grow into nearby tissue or cells break away and enter the bloodstream or lymphatic system eventually affecting other organs. The spread of cancer is called metastasis.

Breast Structure

Breast cancer is identified by different names, depending on where it starts in the woman's breast. A woman's breast is made up of breast tissue, blood vessels, nerves, ducts, lobes and lobules. The breast is made up of about 20 sections called lobes and these have smaller sections, which are the lobules. The lobules of the breast make the milk and the ducts are the tubes that carry the milk to the nipple. The lobes and lobules are connected by the ducts.

What is "ductal" breast cancer?

If a woman has "ductal cancer," it means that the cancer starts in the ducts of the breast. Ductal cancer is the most common type and makes up about 86% of all breast cancers. On the other hand, lobular cancer, which starts in the lobules, makes up about 12% of breast cancers. The other 2% start in the surrounding tissues.

If the cancer grows outside the duct where it starts (meaning the cancer penetrated through the duct), it is called infiltrating or invasive ductal cancer. Mastectomy (removal of the breast) is usually recommended by physicians for invasive ductal carcinoma. If the cancer does not grow outside the duct it will be called intraductal carcinoma or ductal carcinoma in situ, which may be also be termed precancer.

What causes breast cancer?

Scientists do not know the exact cause of breast cancer but they have identified high risk factors for this disease. The most significant are 1) age, 2) family history, and 3) personal history:

  1. Age: Breast cancer risk increases with age. Over two-thirds of breast cancer occurs in women over age 50.
  2. Family History: Family history plays an important role. If a woman's sister or mother has had breast cancer, the chances of getting breast cancer are doubled. Family genes increase the risk of breast cancer. They are called BRCA1 and BRCA2 but only account for 5-10% of all breast cancers. Women who have a family history of breast cancer, or who have a history of benign breast cysts are high risk. Lesser risks that may be genetic include starting menstruation before age 12, late age at menopause (after 55).
  3. Personal History: Personal history also plays a role in breast cancer risk. This can include exposure to environmental contaminants, remaining childless or having the first child after age 30. More recent findings also show that a diet high in fat may increase the chance of breast cancer development.

What is the difference between flat and round breast tumor masses?

Malignant tumors do vary in size, shape, and the rate of dividing cells. The most common type of breast cancer starts in the lining of the ducts called ductal carcinoma. Another less common type of breast cancer, lobular carcinoma, arises in the lobules at the end of the ducts. When the type is diagnosed, it is determined if the cancer is invasive or non invasive. If it is invasive, it has grown into surrounding tissues outside the duct or lobule where it started. Invasive carcinoma is also called infiltrating ductal or lobular carcinoma. An invasive ductal cancer looks like or feels like a firm lump because scar tissue forms around the cancer cells. Invasive lobular cancer is flatter because the cells form finger projections into the surrounding tissues. Rather than feeling a hard round lump, it feels like a thickening. It is difficult for the surgeon to tell if all the lobular cancer is removed with surgery because of the small projections. Lobular cancers do grow to a larger size like you described before they are detected. There are other variations of invasive ductal cancer that are named according to the shape and characteristics of the cancer cells. Examples are tubular (cells look like tubes), papillary (cells stick out like papules or fingers), medullary (cells have same color as brain tissue), mucinous (cells make mucus). This detailed answer is intended to explain the difference between flat and round masses and why the surgeon did not get all of the mass with the first surgery.

I have breast cancer and am wondering about all of the treatment options available to me.

The standard treatment for breast cancer has been surgery mastectomy or lumpectomy, radiation therapy, chemotherapy or a combination of the three.

In the past few years, new approaches have been successful for certain cases. "Adjuvant therapy" is an extra treatment which is added to the primary treatment in order to prevent a recurrence of the cancer and to prolong survival. An example of adjuvant therapy is the use of the drug, Tamoxifen, for up to five years after chemotherapy, radiation or surgery. Bone marrow transplantation has had limited success. Another treatment that is gaining success is called "Modification of the Immunologic System." This type of treatment uses the body's own regulatory system to resist the invasion of the cancer cells. These agents, classified as biologic response modifiers, are derived from the body's own natural products. Hyperthermia treatment is being studied at this time. This form of treatment uses heat to kill cancer cells.

Doctors may choose from different types of treatment depending upon the extent of the disease at the time of diagnosis, your medical history, the type of tumor, and other factors. Before you consent to any course of treatment, the doctor should let you know the recommended procedure, its purpose, the risks and side effects associated with it, other alternatives, and the advantages and disadvantages of one treatment over another. You may want to seek a second opinion, ask for consultation from an oncologist (a doctor specializing in cancer), or from a plastic surgeon.

Other sources of information you may want to gather are from the American Cancer Society in your area. Look in the telephone book for the number to call. Also, you can call the Cancer Information Service which is a toll free telephone service to answer any questions about cancer. Call 1-800-4-CANCER for that service. The American Cancer Society has many pamphlets and books to educate you and your family about breast cancer. They will give you the names of support groups that will help you through this period of time of treatment and even after. The support groups are women who have had breast cancer and have many things in common. These women who had the same experiences will take away some of the fears that you are all bound to have. Don't forget to go to your local library for books and literature about breast cancer.

What are the symptoms of breast cancer?

The most common symptom found by the woman herself or a health care provider is a painless lump in the breast. At times, a painful lump turns out to be cancer. The characteristics of a cancerous lump are: it is hard, not well defined, and is immovable. Occasionally, breast cancer appears as a lump in the armpit or axilla. One lump or several in the armpit can be a symptom of breast cancer, but can also be due to noncancerous conditions. Bleeding from the nipple is not a common sign of cancer but it can possibly indicate cancer, especially if it is from one side only. Only 4% of nipple discharge on one side is cancer.

A more difficult symptom to be found by the woman herself is a thickening of the tissue somewhere in the breast. Any change in breast size or shape can be due to either non-cancerous conditions or cancer. For example, if one breast becomes more pendulous or the nipples are at different levels, cancer is a possibility. Swelling or edema occurs where the tumor is which causes the ligaments in the breast tissue to pull on the overlying skin causing dimpling of the skin. This is highly suggestive of breast cancer.

Other symptoms that may indicate the possibility of breast cancer are a redness of the skin over a portion of the breast, dimpling of the skin, an orange peel appearance on the skin, redness or scaliness of the nipple, or nipple pain or retraction (turning inward). When the tumor spreads along the ducts, it may pull on the nipple, causing it to invert or turn inward. When tumor cells are multiplying rapidly, they need extra blood supply. A woman may notice more prominent veins running across the breast than usual.

If the early symptoms are ignored and the lump grows to a large size, the skin may become ulcerated, become infected and have a bad odor. This is called ulceration and fungation. In the most advanced cases, the normal lymph drainage is blocked, causing the entire arm to swell in a condition called lymphedema. It is most unfortunate if breast cancer advances to any of these of signs and symptoms. Women who do a breast self exam every month are able to detect changes in the density of the tissue much more easily than a woman who does not know her breast well.

Breast cancer can also be present with no physical symptoms, but still be detectable with a mammogram. A mammogram can detect a small tumor two years before a lump can be felt with breast examination. This is the reason that a mammogram every year at the age of 40 and over is so important for breast health.

The American Cancer Society's guidelines for early detection of breast cancer improve the chances for early treatment and cure. They are:

  1. Breast Self-Exam: Women age 20 and older should perform a breast self examination every month.
  2. Breast Physical Exam: Between the ages of 20 and 39, women should have a clinical breast examination by a health professional every 3 years. After age 40, women should have a breast exam by a health professional every year.
  3. Mammogram: An annual screening mammogram for women age 40 and older.

A yearly mammogram for women age 40 is the best screening device we have to date to identify breast cancer, even before any of the above signs and symptoms occur. A mammogram can detect a tumor less than 1/4 inch or 1/2 cm whereas a tumor usually cannot be felt until it is 1/2 inch or 1 cm. Also, a mammogram will detect deposits of calcium called calcifications that look like white dots on the x-ray. The calcifications cannot be felt, but many times are indications of a malignancy. Early detection is the key to longer survival and cure.

Image of Breast

I have read that it is most common for breast cancer to appear first in the left breast. Is there a reason that you know of?

The occurrence of breast cancer can be a predictable pattern for both in situ and invasive carcinomas. Cancers arise most frequently in the upper and outer hemisphere of the breast than the medial or lower hemisphere. If you divide the breast in four quadrants, the upper outer quadrant has a higher incidence of cancer. The least frequent location of breast cancer is the lower inner quadrant. Another way to describe the location of frequency is to look at the breast like a clock. Breast cancer is more frequent between 12 and 3 of the left breast and between 12 and 9 in the right breast. The distribution of breast cancer is related to the tissue volume of the breast. The breast tissue volume is slightly greater in the left breast than the right, which may account for a slight predominance of cancer in the left breast. The left breast may have as much as 2-3% more tissue volume than the right but not always. Some studies have shown the frequency of breast cancer higher in the right breast.

Where can breast cancer spread after a surgery has been performed (lump removed)?

When a breast cancer tumor is removed surgically, it is analyzed in the laboratory for the type of cancer, that is, where it started in the breast and the stage of the cancer. It is important to determine whether the cancer has invaded surrounding tissue and lymph nodes or if it has stayed in the place of origin and not spread. The pre-invasive form is known as "in situ" cancer (staying in place). If the tumor or cancerous breast tissue is removed at this early stage, the spread is prevented. If it has spread, it will be detected in the surrounding tissue and lymph nodes and be classified as invasive, or have the potential to grow in other parts of the body. The spread of breast cancer can be classified in terms of stages. Staging is a system for classifying cancer according to the size of the tumor, local extension to the chest wall or skin, the number and location of lymph nodes involved, and whether the cancer has spread to other parts of the body. It is important to emphasize the in situ tumor that has stayed in place has not spread anywhere as yet and will not spread if removed at this stage.

Other Risk Factors

Recently I have been diagnosed with calcifications in my breast and elevated prolactin levels. I've read that elevated prolactin levels are indeed associated with breast cancer. What can you tell me about this?

Prolactin is one of the hormones secreted by the anterior pituitary gland, known to be involved in breast development and to stimulate and sustain lactation in postpartum women. During breast maturation, the mammary gland lobules are formed. The lobules are where milk is made during lactation. Normally, this process occurs throughout pregnancy. There are researchers who have published studies indicating that breast cancer risk is lowered when the maturation stage is completed early. This explains why the incidence of breast cancer is reduced with those women who have early pregnancies and why women who did not have children have an increased risk of breast cancer. Research is being done now to develop treatments that can speed up breast maturation in young women.

There are different reasons for increased prolactin. One condition called galactorrhea is manifested by excessive or spontaneous milk flow when not breast feeding. Something in the woman's body is abnormal. Among others, one reason for the increased prolactin with galactorrhea may be a small tumor in the anterior pituitary. A medication can block the prolactin production. There have been studies of the prolactin receptors in women with breast cancer. The prolactin receptors facilitate the growth of breast cancer cell lines which suggest some breast cancers may be prolactin dependent. More studies are being done to determine the clinical correlation of breast cancer and prolactin. I encourage you to discuss the qualities of the calcifications you have, as to whether they look to be harmless or cancerous. The calcifications can be biopsied so that you know for sure.

What are some recently dispelled myths concerning the causes of breast cancer?

It was a common belief that women who had fibrocystic disease of the breast were at high risk for breast cancer. This has not been shown in scientific studies. The American College of Pathologists made a statement in the late 1980's that fibrocystic disease of the breast does not increase to risk of breast cancer. Another fear that women have is that a blow or trauma to the breast will cause breast cancer. This is not true. Another myth that may seem silly to some is that cancer is contagious. Women have reported losing their job or being ignored by coworkers. Cancer is not contagious. A common breast pain called mastalgia causes many women discomfort and fear that of cancer. Mastalgia can be related to the menstrual cycle or it can be constant. Little is known about the treatment of these breast pains only that it is not breast cancer.

Causes of breast cancer are not just one thing but a combination of risk factors traced to the environment, genetics, and lifestyle, for example. A risk factor is anything that increases a person's chance of getting a disease. For a good summary of proven and unproven risk factors from the American Cancer Society, click here.

Why is there a greater risk of breast cancer for women who have never had children?

This risk factor has been identified in textbooks for a long time but the reason is still under investigation. Dr. Susan Love in the third edition of her Breast Book theorizes the following: The breast tissue between the beginning menarche (first period) and the first pregnancy is more sensitive to carcinogens (factors that can cause cancer). Pregnancy may stop the cells from being susceptible to carcinogens and the ability to mutate to a cancer. The hormones secreted during pregnancy results in maturing the breast tissue. The conclusion seems to be that pregnancy does affect breast cancer risk. That is, breast cancer is a higher risk for women who have never been pregnant. The longer the time from the first period, when breast cells can easily change to a mutated cell, the greater the chance they have to develop into cancer when exposed to a carcinogen (i.e. diet, radiation, alcohol).

I am considering taking the birth control pill, but I have a family history of breast cancer. Should I take "the pill"?

Many studies have been done to determine if birth control pills or oral contraceptives (OCs) increase the risk of breast cancer. The results have been contradictory. Birth control pills (OCs) ordinarily contain the hormones estrogen and progesterone. Newer OCs contain fewer hormones than years ago and may be less of a risk of cancer. The two factors that seem to be most related to breast cancer and the use of OCs is timing and duration. In general, the studies have found that long-term OCs use before the first pregnancy (4 years or over) have increased cancer risk. The risk increases significantly with longer use before first childbirth. You need to see a physician (gynecologist) for information about current birth control pills and alternative birth control methods. Even if there is a slight risk of breast cancer the risk may be more important to you than an unwanted pregnancy or abortion. Only you can make this decision.

How do I calculate my breast cancer risk? A physician told me there is a way to calculate the risk.

There is a way, but explaining it entirely is much too long for here, so I will refer you to Dr. Susan Love's Breast Book, published by Addison-Wesley, revised in 1995. And, I will explain briefly what you want to know. Dr. Love discusses in detail 3 kinds of risk related to breast cancer: absolute, relative and attributable risks. She devotes an entire chapter to risk factors and how to calculate which has many variables. Absolute risk is the rate of breast cancer, or death from breast cancer, in the general population. It is reported as the number of cases per a named population (e.g. 50 cases per 100,000 annually) or as a cumulative risk up to particular age (e.g. 1 in 10 lifetime figure). Relative risk compares the number of breast cancers with a particular risk factor to women without that factor. For example, 1 out of 30 will get breast cancer with no family history, whereas 6 out of 30 will get breast cancer that have a family history of breast cancer. Attributable risk looks at the amount of disease in the population that could be prevented by altering risk factors. For example, if you take all breast cancer patients, 25% of the cases could be prevented by lowering fat in diet. Keep in mind that this explanation is very brief. You should read this chapter in Dr. Love's book, or find another resource, for full understanding. Risk factors refer to those things that make some people more susceptible than others to a particular disease.

Does hormone replacement therapy increase your chance of getting breast cancer?

This is a difficult question as the research does not give us a definitive answer. Some studies show that HRT (hormone replacement therapy) taken over 10-15 years may increase breast cancer, while other studies with women taking the hormones in a shorter duration show no affect on breast cancer. We need more long studies to make a statement about HRT and breast cancer. We do know that estrogen treatment along with calcium intake and exercise reduces bone loss and bone fractures with menopause by 25 percent. Studies have also shown that women on HRT have lower risk of coronary heart disease compared to non-users. I think each woman must weigh the risks and benefits of hormone therapy for herself. She needs to look at her family history of breast cancer, heart disease and osteoporosis to make a judgment about whether HRT will contribute to her wellness. If there is a family history of breast cancer, or the woman has had breast cancer previously, then HRT may not be indicated for that individual. If there is no history of breast cancer but a history of heart disease, then HRT may be beneficial to the individual to help prevent future illness. It is important for every woman to weigh her own risks and benefits. Talk it over with you physician and nurse specialist.

I recently received an email stating that the leading cause of breast cancer is the use of anti-perspirant. It said that the human body has a few areas that it uses to purge toxins: behind the knees, behind the ears, groin area, and armpits. The toxins are purged in the form of perspiration. Anti-perspirant prevents you from perspiring, thereby inhibiting the body from purging toxins from below the armpits. The body deposits them in the lymph nodes below the arms since it cannot sweat them out. This causes a high concentration of toxins and leads to cell mutations a.k.a. CANCER. Is this true?

The American Cancer Society says, "Recent Internet e-mail rumors have suggested that chemicals in underarm antiperspirants are absorbed through the skin, interfere with lymph circulation, and cause toxins to accumulate in the breast that eventually lead to breast cancer. There is no experimental or epidemiological evidence to support this rumor. Chemicals in products such as antiperspirants are tested thoroughly to assure their safety. The claims about toxin accumulation are not consistent with scientific concepts of carcinogenesis (cancer formation)." To read more about breast cancer risk factors and rumors, connect to the American Cancer Society web site.

More articles about breast cancer:

Inheritance, Genetics and Breast Cancer

Men and Breast Cancer

For more information:

Go to the Breast Cancer health topic, where you can:

This article is a NetWellness exclusive. NetWellness Article

Last Reviewed: Jun 12, 2002

University of Cincinnati Janet Trigg, RN, MSN, EdD
Formerly:
College of Nursing
University of Cincinnati
Janet   Trigg, RN, MSN, EdD