Breast cancer facts are compiled annually by groups like the American Cancer Society and other reputable organizations dedicated to women's health advocacy. The purpose of gathering these breast cancer facts is to help medical professionals direct their research and treatment and inform consumers about breast cancer facts, including breast cancer prevention, detection, and treatment. Breast cancer facts inform people about the nature and scope of this leading cancer.

The following breast cancer facts are intended to provide some basic information about this type of cancer.

1. What is breast cancer? After skin cancer, breast cancer is the leading type of cancer and second most common fatal cancer for women. Breast cancer begins in the breast tissue, usually in the lobules (milk producing glands) or in the ducts (connecting the nipple and the lobules). Most tumors that develop in the breasts are benign, some are malignant but have not spread (called in situ), and others are invasive and malignant meaning they have spread to other areas of the body. The breast cancer stages classify the extent to which breast cancer has spread.
2. Who gets breast cancer? Ninety-nine percent of all breast cancer patients are women. Men are at a very low risk of developing breast cancer, though family history and other factors may increase their risk. Ninety-four percent of those diagnosed with breast cancer between 1996 and 2000 were women aged 40 and older. People with a family history of breast cancer on either side of their family may also be more likely to develop breast cancer. Caucasian women also appear to be at a greater risk for breast cancer than women of other ethnicities. Certain environmental factors can also increase one's risk of developing breast cancer.
3. How common is breast cancer? According to the American Cancer Society, 211,240 women in the United States will be diagnosed with invasive breast cancer in 2005. Another 58,490 will be diagnosed with in situ breast cancer (cancer that has not spread to other tissues). This year 40,410 women and 460 men will die of breast cancer in the United States. The World Health Organization estimates that 1.2 million people worldwide will be diagnosed with breast cancer this year.
4. How is breast cancer diagnosed? Breast cancer is diagnosed in a number of ways and often involves a number of medical tests and procedures. Monthly breast self examinations are recommended for all women over age 20, since 70 percent of all breast lumps are detected by the patient. Women over age 40 and those with risk factors are encouraged to have a mammogram and clinical breast cancer screening every year. Mammography, ultrasonography, MRI, and breast tissue biopsy are common tools in diagnosing breast cancer.
5. What does a diagnosis of breast cancer mean? A breast cancer diagnosis is not an emergency, nor is it a death sentence. The consequences of a breast cancer diagnosis depend on the nature and aggressiveness of the cancer. There are a variety of therapies available to women with all stages of breast cancer.
6. How is breast cancer treated? The exact treatment a patient receives is determined by the patient and her physician. Radiation therapy is used to destroy cancer cells before or after surgery. Chemotherapy and hormone therapy are often helpful for women in various stages of breast cancer. Surgery is often a recommended option for women with breast cancer. A lumpectomy is a conservative procedure whereby the tumor and a small amount of surrounding tissue are removed. A mastectomy removes the entire breast, and sometimes surrounding tissues.