Your risk of developing invasive breast cancer at some time during your lifetime is one in eight. This sounds high, but if you consider the term, "lifetime," it helps put your risk in perspective. It means that one in 233 women in their 30s will be diagnosed with beast cancer; one in 69 in their 40s; one in 36 in their 50s; and in 27 in their 60s. The "one in eight" applies to women in their 80s and 90s. However, as you can see, your risk for developing breast cancer increases with age. In fact, other than being a woman, age is the single greatest risk factor for breast cancer.

Your risk is higher if you have:

• A personal first-degree (mother, sister, daughter) family history

• Biopsy-confirmed atypical hyperplasia, or an overgrowth of abnormal cells that are not cancerous

• A mutation in the BRCA1 or BRCA2 tumor suppressor genes

• A mother, sister or daughter with a BRCA1 or BRCA2 mutation, even if you are yet to be tested yourself

• A lifetime risk of breast cancer that has been scored at 20 to 25 percent based on one of several accepted risk assessment tools that examine family history and other factors; see the American Cancer Society's Web site, www.cancer.org, for more information

• Had radiation to the chest between the ages of 10 and 30

• Li-Fraumeni syndrome, Cowden syndrome or Bannayan-Riley-Ruvalcaba syndrome or you have a first-degree relative with one of these syndromesLobular carcinoma in situ (LCIS), is not a true cancer, though it may be a marker for later cancer risk. Most experts agree that LCIS does not often become an invasive cancer, but women with LCIS do have an increased risk of developing invasive breast cancer.

• A biopsy-confirmed atypical lobular neoplasia (ALN), which is a noncancerous breast disease characterized by the growth of abnormal cells. ALN may be discovered on the mammogram or when a biopsy is done for a lump.

Your risk is somewhat higher if you have:

• Dense breast tissue

• Early menstruation (beginning at 12 or younger)

• Late menopause (age 55 or older)

• Never had children or had your first baby after age 30

• Have used hormone therapy for a long time

Your risk may be higher if you:

• Smoke

• Drink heavily

• Are obese

• Are a gay or bisexual woman. These women have a greater risk of breast cancer than other women not because of their sexual orientation, but because they are less likely to have had children. They also may have more lifestyle-related risk factors for breast cancer than heterosexual women, including obesity and cigarette smoking. If you are a lesbian or bisexual woman, you may want to find a lesbian- and/or bisexual-sensitive health professional and schedule regular physicals that include clinical breast examinations and mammography.

You may have read or heard that an induced abortion or miscarriage can increase a woman's risk of developing breast cancer later in life. But according to the National Cancer Institute (NCI), newer studies have consistently shown no association between miscarriages or induced abortions and breast cancer risk.

A majority of women will have one or more risk factors for breast cancer. However, most risks are so low that they only partly explain the high frequency of the disease in the population.

While you can't alter some of your personal risk factors for developing breast cancer, such as age or family history, you can adopt specific lifestyle choices, such as maintaining your ideal body weight and exercising, to reduce your risk of the disease.

Early detection of breast cancer, however, provides the best opportunity for successful treatment and reduces your chances of dying from breast cancer.

There are three main ways to detect abnormalities in your breasts that may be cancerous: breast self-examination, mammograms and regular breast exams by your health care professional. Other imaging studies such as ultrasound and MRI (magnetic resonance imaging) can also help find cancer in the breast. As a result of new guidelines released by the ACS in March 2007, MRI together with a yearly mammogram is now recommended for women with the highest risk of developing breast cancer (see the list above for risks that are considered to be higher than average). MRI scans are more sensitive than mammograms at detecting an abnormality in women with dense breasts. The two tests together give health care professionals a better chance of finding breast cancer in its early stages, when it is the most treatable. The new guidelines recommend that high-risk women begin getting MRIs and mammograms at age 30, unless their health care professionals suggest a different age.

Breast self-exam (BSE) is an option for women age 20 and older. Research has shown that BSE slightly increases a woman's chance of finding a breast lump compared to discovering one by chance. Overall, the main goal of a BSE is to help a woman become familiar with the look and feel of her breasts so she can report any changes to her health care provider right away. Some women feel very comfortable taking a step-by-step approach to doing a monthly BSE. Other women prefer to examine their breasts in a less systematic way, while they are showering or getting dressed, with an occasional more thorough exam. As long as a woman monitors the look and feel of her breasts regularly, either technique is acceptable.

Health care professionals should discuss the benefits and limitations of BSE with women 20 and older so they can make informed decisions about the practice.

Ask your health care professional to show you how to perform a BSE correctly. You may also want to ask for a brochure to help when you get home. It may take several months for you to become familiar with the routine and to learn what to expect to feel. But with practice, BSE can increase your chances of noticing anything abnormal about your breasts.

As you perform BSE, remember the seven "Ps:"

• Position to assume while inspecting or palpating (feeling) the breasts

• Perimeter (boundaries) of breast tissue to be examined

• Palpation using the pads of three fingers

• Pressure of the fingers

• Pattern of search

• Practice of feedback

• Plan of action for breast health

If you find a suspicious lump or notice something else abnormal, make an appointment with your health care professional. He or she will perform an exam and will likely have you undergo a mammogram. The majority of breast changes found by women who regularly perform BSEs are not cancerous.

Mammograms

The value of mammography is that it can identify potentially cancerous breast abnormalities at an early stage before they can be felt. While mammograms can detect a breast lump up to two years before it can be felt during a physical examination, they can miss up to 20 percent of breast cancers.

According to the ACS March 2007 updated screening guidelines, women at a high risk of breast cancer age 30 and older (or at an age determined by their health care professionals) should have:

• An annual mammogram together with an MRI

According to the ACS breast cancer screening guidelines, women at average risk of breast cancer age 40 and older should have:

• An annual mammogram

• An annual clinical breast exam performed by a health care professional

While BSEs are optional, as noted above, they are still strongly encouraged.

According to ACS, women ages 20 to 39 should have:

• A clinical breast exam performed by a health care professional at least every three years, as part of their periodic (regular) health exam

A mammogram is a specialized x-ray of your breasts from various angles. Although it doesn't hurt, it can be uncomfortable for some women or even a little embarrassing. A health care professional moves and flattens (breast compression) your breasts on the x-ray machine so it is in the best position for taking x-ray images. The entire procedure typically takes less than 15 minutes.

Ultrasound and MRI

If something abnormal is detected in a mammogram, the next step is usually to take additional x-ray views or an ultrasound.

Ultrasound is also used to create visual images of breast tissue. Ultrasonography, or ultrasound, uses high-frequency sound waves. The images it creates can be viewed on a monitor and allows your health care professional to see if a breast lump is a fluid-filled cyst (not cancer) or a solid mass (which may or may not be cancer). Ultrasound may be used with a mammogram, and the images produced are printed and/or stored as video.

Use of MRI of the breast is now recommended together with an annual mammogram as a standard diagnostic tool in women at a high risk of breast cancer. This technology uses magnetic fields to show differences between normal and abnormal tissue.

For an MRI scan, you lie in a specially designed structure that houses the magnetic field. Contrast material is injected into your veins, and the MRI image shows the dye coursing through the blood vessels in your breasts.

This test is used to detect cancer, determine the extent of disease, monitor response to therapy and screen women at high risk for breast cancer.

A relatively new technology called CADstream, designed specifically for breast MRI, makes interpretation of MRI data more efficient, as well as improves the images produced by the scan. CADstream uses a computer-aided detection (CAD) system that helps radiologists increase quality control of breast MRI studies (it corrects for patient movement during a scan) and eliminates manual processing of hundreds of images usually produced by one scan.

Computer-assisted diagnosis, or CAD, is also used during a second reading of mammograms to improve the accuracy of the reading.

Biopsy

Even after an ultrasound or mammogram, if your health care professional still believes the area is suspicious, he or she may recommend a core-needle biopsy, taking a sample of breast tissue by needle and sending it to a pathologist to determine if it's cancer. Biopsies can usually be done in your doctor's office under local anesthesia. Fine needle aspiration is frequently performed. However, the rate of false negatives is very high and most often additional studies, like checking for estrogen or progesterone receptors based on an aspiration, are hard to perform.

If Breast Cancer is Found

If breast cancer is found, more tests will be done to find out the size and extent of the cancer in the breast and to determine whether the cancer has spread from the breast to other parts of the body. This is called staging. To plan treatment, your health care professional needs to know the stage of the disease. The following stages are used for breast cancer:

• Stage 0: Carcinoma in situ: About 20 percent of breast cancers are very early cancers, sometimes called ductal carcinoma in situ (DCIS).

• Stage I: The cancer is no larger than two centimeters (about one inch) and cannot be detected outside the breast.

• Stage II: Any of the following may be true:

• The cancer is no larger than two centimeters but has spread to the lymph nodes under the arm (the axillary lymph nodes).

• The cancer is between two and five centimeters.

• The cancer may or may not have spread to the lymph nodes under the arm (axillary lymph nodes).

• Stage III: Stage III is divided into stages IIIA and IIIB. Stage IIIA is defined by either of the following: The cancer is smaller than five centimeters and has spread to the lymph nodes under the arm, and the lymph nodes are attached to each other or to other structures; or, the cancer is larger than five centimeters and may or may not have spread to the lymph nodes under the arm.

  Stage IIIB is defined by either of the following: The cancer has spread to tissues near the breast (skin or chest wall, including the ribs and the muscles in the chest); or, the cancer has spread to lymph nodes inside the chest wall along the breastbone.

• Inflammatory breast cancer: This class of breast cancer is uncommon. The breast looks as if it's inflamed because it is red, swollen and warm. The skin may show signs of ridges or it may have a pitted appearance. Also, a biopsy of skin will show tumor cells. This type of breast cancer tends to be more aggressive. Inflammatory breast cancer that is not detected outside of the breast and underarm lymph nodes is Stage IIIB.

• Stage IV: The cancer has spread to other organs of the body, most often the bones, soft tissue (skin), lungs, liver or brain.

• Recurrent: Recurrent disease means that the cancer has come back (recurred) after it has been treated. It may come back in the breast, in the soft tissues of the chest (the chest wall) or in another part of the body.