Breast Cancer

In breast cancer, cells in your breast begin growing abnormally – often for unknown reasons. These cells divide more rapidly than healthy cells and may spread through your breast or into other parts of your body. The most common type of breast or into other parts of your body. The most common type of breast cancer begins in the ducts designed to carry milk after childbirth, but cancer may occur in the small sacs that produce milk (lobules) or in other breast tissue.

Breast cancer is the disease many women fear most, though they're far more likely to die of cardiovascular disease than they are of all forms of cancer combined. Still, breast cancer is second only to lung cancer as a cause of cancer deaths in American women. More than 200,000 American women are diagnosed annually with breast cancer. And nearly 40,000 American women die annually of breast cancer. Although rare, breast cancer can also occur in men.

Yet there's more reason for optimism with regard to breast cancer than ever before. Great strides have been made in diagnosis and treatment in the last 25 years. In 1975 a diagnosis of breast cancer usually meant radical mastectomy — removal of the entire breast along with underarm lymph nodes and skin and muscles underneath the breast. Today, radical mastectomy is rarely performed. Instead, there are more and better treatment options, and many women are candidates for breast-sparing operations, such as lumpectomy.

Emphasis is also being placed on early detection, lifestyle changes and therapies such as tamoxifen that may reduce the risk of breast cancer. In addition, a growing network of agencies and resources exist to help those who have just received a diagnosis, are facing treatment decisions or are living with breast cancer.

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Knowing the signs and symptoms of breast cancer may help save your life. When the disease is discovered early, you have more treatment options and a better chance for long-term recovery. In fact, when breast cancer is diagnosed and treated in its early stages, the five-year survival rate is 95 percent.

Most breast lumps aren't cancerous. Yet the most common sign of breast cancer for both men and women is a lump or thickening in the breast. Often, the lump is painless. Other signs of breast cancer include:

• A spontaneous clear or bloody discharge from your nipple
• Retraction or indentation of your nipple
• A change in the size or contours of your breast
• Any flattening or indentation of the skin over your breast
• Redness or pitting of the skin over your breast, like the skin of an orange

If you find a lump or other change in your breast and haven't yet gone through menopause, you may want to wait through one menstrual cycle before seeing your doctor. If the change hasn't gone away after a month, have it evaluated promptly.

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The American Cancer Society estimates that 75 percent of breast cancer cases occur in women with no known risk factors. At the same time, having one or even several risk factors doesn't mean you'll develop the disease. The following factors may increase your risk of breast cancer:

• Sex - Being a woman is your greatest risk factor. Although men can develop breast cancer, it's 100 times more common in women.
• Age - Your chances of developing breast cancer increase as you get older. The disease rarely affects women under 25 years of age, whereas close to 80 percent of breast cancers occur in women over age 50. At age 40, you have a one in 252 chance of developing breast cancer. By age 85, your chance is one in eight.
• A personal history of breast cancer - If you've had breast cancer in one breast, you have an increased risk of developing cancer in the other breast.
• Family history - Women who have a mother or sister with breast cancer have a greater chance of developing breast cancer themselves. In general, the more relatives you have with breast cancer who were premenopausal at the time of diagnosis, the higher your own risk. If you have one close relative with breast cancer, your risk is doubled. If you have two or more relatives, your risk increases even more.
• Genetic predisposition - Between 5 percent and 10 percent of breast cancers are inherited. Defects in one of several genes, especially BRCA1 or BRCA2, put you at greater risk of developing the disease. Usually these genes help prevent cancer by making proteins that keep cells from growing abnormally. But if they have a mutation, the genes aren't as effective at protecting you from cancer. Women who are of Ashkenazi (Eastern and Central European Jewish) ancestry are especially at risk.
• Excess weight - The relationship between excess weight and breast cancer is complex. In general, weighing more than is healthy for your age and height increases your risk if you've gained the weight as an adult and especially after menopause. The risk is even greater if you have more body fat in the upper part of your body. Although women usually have more fat in their thighs and buttocks, they tend to gain weight in their abdomens starting in their 30s, which can increase their risk.
• Exposure to estrogen - The longer you're exposed to estrogen, the greater your breast cancer risk. In general, if you have a late menopause (after age 55) or you began menstruating before age 12, you have a higher risk of developing breast cancer. The same is true for women who never had children, or whose first pregnancy occurred when they were age 35 or older.
• Race - Caucasian women are more likely to develop breast cancer than are black or Hispanic women. Black women, however, are more likely to die of the disease because they tend to be diagnosed at a later stage than are white women. But socioeconomic factors, rather than race, may account for the difference in mortality. A study of more than 5,000 Detroit-area women published in the Journal of the National Cancer Institute found that women of all races with incomes below the poverty level were more likely to be diagnosed with late-stage breast cancer and three times more likely to die of the disease than were women with higher incomes. The study's authors concluded that low-income women weren't receiving the routine medical care that would allow breast cancer to be discovered earlier.
• Hormone therapy - In July 2002, a study sponsored by the National Institutes of Health (NIH) was halted as researchers reported that hormone therapy, once considered standard treatment for menopausal symptoms, actually posed more health risks than benefits. Among those was a slightly higher risk of breast cancer for women taking the particular combination of hormone therapy — estrogen plus progestin — used in the study. In addition, combination hormone therapy can make malignant tumors harder to detect on mammograms, leading to cancers that are diagnosed at more advanced stages, when they're harder to treat. Because combination hormone therapy can result in serious side effects and health risks, work with your doctor to evaluate the options and decide what's best for you.
• Birth control pills - Because of the recent information on hormone therapy, many younger women are concerned about the relationship between birth control pills and breast cancer. Unfortunately, there's no clear answer. A large study of women between the ages of 35 and 64 published in June 2002 in the New England Journal of Medicine concluded that current or former use of oral contraceptives didn't increase the risk of breast cancer. But the American Cancer Society says that women currently using the pill may have a slightly increased risk, whereas women who stopped using oral contraceptives 10 years ago probably don't have such a risk. For the latest information on the pill and breast cancer, talk to your doctor.
• Smoking - A Mayo Clinic study published in April 2001 found that smoking significantly increases the risk of breast cancer in women with a strong family history of breast and ovarian cancers.
• Exposure to certain carcinogens - Polycyclic aromatic hydrocarbons (PAHs) are chemicals found mainly in cigarette smoke and charred red meat. Studies have shown that exposure to these chemicals can significantly increase your chances of developing breast cancer. Exposure to certain pesticides also may increase your risk, but more research needs to be done to establish a clear link.
• Excessive use of alcohol - Women who consume more than one alcoholic drink a day have a 20 percent greater risk of breast cancer than do women who don't drink. The National Cancer Institute recommends limiting alcohol intake to no more than one drink daily.
• Unusual sleep patterns - You may have an increased risk of breast cancer if you work the graveyard shift or are up often during the night. The risk seems to be greatest if you don't sleep between 1 a.m. and 2 a.m., when levels of melatonin — a sleep-regulating hormone — are highest. Women who reported missing sleep during this period at least three nights a week had a 40 percent increased risk of developing breast cancer. Women who worked nights fared worse, with a 60 percent increased risk. Researchers speculate that suppression of melatonin by exposure to light may increase the release of estrogen by the ovaries.

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Clinical exams and mammography won't prevent breast cancer. But these important procedures can help detect cancer in its earliest stages. The sooner you receive a diagnosis, the more options you have, the more effective your treatment and the better your overall prognosis.

In most cases, doctors don't know what causes breast cancer. The number of tumors associated with a mutation in the breast cancer gene is small — about 10 percent to 15 percent. That's why research is focusing on newer measures you can take that may help reduce your risk.

Following are some suggestions to reduce your risk:

• Ask your doctor about aspirin - Taking an aspirin just once a week may help protect against breast cancer. A study published in the Journal of the American Medical Association in May 2004 found that women who took aspirin once a week for six months or longer were 20 percent less likely to develop breast cancer than women who didn't take the drug. Women who took a daily aspirin had an even greater reduction in risk — 28 percent. Regular use of ibuprofen (Advil, Motrin, others) also seems to help protect against breast cancer, but not as effectively as aspirin. Tylenol works differently from aspirin and ibuprofen and has no anti-cancer benefit.
  Aspirin and ibuprofen are effective only against breast cancers that have receptors for the female hormones estrogen and progesterone, which are known to stimulate tumor growth. The drugs work by reducing estrogen levels in your body and breast tissue. They do this by blocking a hormone-like substance (prostaglandin) that's needed to activate an enzyme (aromatase activity) important in the synthesis of estrogen.
  If you've had a heart attack or stroke, taking an aspirin a day may help prevent future attacks. And aspirin also appears to protect against other types of cancer, including cancers of the colon and rectum, esophagus and stomach. Although these results are encouraging, be sure to talk to your doctor before you start taking aspirin as a preventive measure. When used for long periods of time, aspirin can cause serious side effects including stomach irritation, bleeding and ulcers; bleeding in the intestinal and urinary tracts; and hemorrhagic stroke. In general, you're not a candidate for aspirin therapy if you have a history of ulcers, liver or kidney disease, bleeding disorders, or gastrointestinal bleeding.
• Limit alcohol - A strong link exists between alcohol consumption and breast cancer. As little as 10 grams of alcohol a day — an average drink contains about 15 grams of alcohol — may increase your lifetime risk of breast cancer by 10 percent. The type of alcohol consumed — wine, beer or mixed drinks — seems to make no difference. To help protect against breast cancer, limit the amount of alcohol you drink to less than one drink a day or avoid alcohol completely. Some studies indicate that folic acid might help reduce the risk of breast cancer in women who consume moderate amounts of alcohol.
• Maintain a healthy weight - There's a clear link between obesity — weighing more than is appropriate for your age and height — and breast cancer. This is especially true if you gain the weight later in life, particularly after menopause.
• Discuss long-term hormone therapy with your doctor - The Women's Health Initiative study of 2002 raised concerns about the use of hormone therapy for symptoms of menopause. Among other problems, long-term treatment with estrogen-progestin combinations such as those found in the drug Prempro increased the risk of breast cancer. If you're taking hormone therapy, consider your options with your doctor. You may be able to manage your menopausal symptoms with exercise, dietary changes or non-hormonal therapies that have been shown to provide some relief. If none of these work for you, you may decide that the benefits of short-term hormone therapy outweigh the risks. In that case, your doctor will likely encourage you to use the lowest dose of hormone therapy for the shortest period of time.
• Stay physically active - The Nurses' Health Study, a long-term study of more than 120,000 female nurses, found that women who exercised for at least one hour a day reduced their breast cancer risk by 18 percent. Those who exercised for 30 minutes every day reduced their risk by 10 percent. Walking was found to be as effective as more vigorous types of exercise. Other studies have shown that women who exercise consistently for at least 10 years of life — whether in adolescence or adulthood — can cut their risk of cancer by as much as 75 percent. A good place to start is to aim for at least 30 minutes of exercise on most days. If you haven't been active before, start out slowly and work up gradually. Try to include weight-bearing exercises such as walking, jogging or dancing. These have the added benefit of keeping your bones strong.
• Eat foods high in fiber - Try to increase the amount of fiber you eat to between 20 and 30 grams daily — about twice the amount in an average American diet. Among its many health benefits, fiber helps reduce the amount of circulating estrogen in your body. Foods high in fiber include fresh fruits and vegetables and whole grains.
• Limit fat in your diet - Several observational studies have reported a correlation between a high dietary fat intake and breast cancer risk. What's more, reducing the amount of fat in your diet decreases your risk of some other cancers as well as the risks of diabetes, cardiovascular disease and stroke. And it helps you maintain a healthy weight, which also reduces your risk of breast cancer. It's a good idea to limit your fat intake to less than 35 percent of your daily calories, with no more than eight percent to 10 percent coming from saturated fats.
• Eat plenty of fruits and vegetables - Fruits and vegetables contain vitamins, minerals and antioxidants that can help protect you from cancer. The American Cancer Society recommends five or more servings of fruits and vegetables every day. Look for deep green and dark yellow or orange fruits and vegetables, such as Swiss chard, bok choy, spinach, cantaloupe, mango, acorn or butternut squash and sweet potatoes. Also try to eat vegetables from the cabbage family, including broccoli, brussels sprouts and cauliflower. Lycopene, a nutrient found in tomatoes and other red fruits and vegetables such as strawberries and red bell peppers, may be a particularly powerful anticancer chemical.
• Avoid exposure to pesticides - The molecular structure of some pesticides closely resembles that of estrogen. This means they may attach to receptor sites in your body. Although studies have not found a definite link between most pesticides and breast cancer, it is known that women with elevated levels of pesticides in their breast tissue have a greater breast cancer risk.
• Avoid unnecessary antibiotics - The results of a large-scale study published in the Feb. 18, 2004, issue of the Journal of the American Medical Association found a correlation between antibiotic use and breast cancer. The longer antibiotics were used, the greater the risk. Researchers caution, however, that other factors, such as underlying illness or a weakened immune system, rather than antibiotics themselves may account for the elevated cancer risk. At the same time, taking antibiotics when they're not needed can lead to drug-resistant strains of bacteria, a grave and growing problem. And because antibiotics can cause diarrhea and other side effects, it's best to avoid them unless absolutely necessary.

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A diagnosis of breast cancer is one of the most difficult experiences you can face. In addition to coping with a life-threatening illness, you must make complex decisions about treatment. Remember, in most cases no one right treatment exists for breast cancer. Instead, you'll want to find the approach that's best for you.

To do that, you'll need to consider many different factors, including the type and stage of your cancer, your age, risk factors, where you are in your life, the size and shape of your breasts, and your feelings about your body.

Before making any decisions, learn as much as you can about the many treatment options that exist. Talk extensively with your health care team. Consider a second opinion from a breast specialist in a breast center or clinic. Don't be afraid to ask questions. In addition, look for breast cancer books, Web sites and information available from organizations such as the American Cancer Society and the National Cancer Institute (NCI) sponsored cancer centers. Talking to other women who have faced the same decision also may help. This may be the most important decision you ever make.

Treatments exist for every type and stage of breast cancer. Most women will have surgery and an additional (adjuvant) therapy such as radiation, chemotherapy or hormone therapy. And several experimental treatments are now offered on a limited basis or are being studied in clinical trials.

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There’s more reason for optimism with regard to breast cancer than ever before. There is a 96% five-year survival rate for women with breast cancer if the suspicious mass is detected early and followed by treatment.

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* Text Resources: The Mayo Clinic Staff