Benign: Not cancerous; not malignant. The main types of benign breast problems are fibroadenomas and fibrocystic change. (See also fibroadenoma, fibrocystic change).

Bilateral: Affecting both sides of the body; for example, bilateral breast cancer is cancer occurring in both breasts at the same time (synchronous) or at different times (metachronous).

Biologic response modifiers: Substances that boost the body's immune system to fight against cancer. (See also interferon).

Biological therapy: Treatment to restore the ability of the immune system to fight infection or other diseases.

Biopsy: A procedure in which tissue samples are removed from the body for examination of their appearance under a microscope to find out whether cancer or other abnormal cells are present. A biopsy can be done with a needle or by surgery.

Blood count: The number of red blood cells, white blood cells, and platelets in a sample of blood.  Also called complete blood count (CBC).

Bone densitometry: Exam used to measure a patient's bone mineral density of various parts of the body, such as the spine, hip, heel, or wrist.  The exam is useful in determining whether a patient has osteoporosis.    

Bone marrow transplant: A complex treatment that may be used when breast cancer is advanced or has recurred. The bone marrow transplant makes it possible to use very high doses of chemotherapy that would otherwise be impossible. Autologous bone marrow transplant means that the patient's own bone marrow is used. An allogeneic bone marrow transplant uses marrow from a donor whose tissue type closely matches the patient's. A portion of the patient's or donor's bone marrow is withdrawn, cleansed, treated, and stored. The patient is then given high doses of chemotherapy that kill the cancer cells but also destroy the remaining bone marrow, thus robbing the body of its natural ability to fight infection. The cleansed and stored marrow is given by transfusion (transplanted) to rescue the patient's immune defenses. Although this method has been widely reported by the media, and it has given good results in many people, it has not been scientifically proven to be more effective than conventional therapies in treating breast cancer. It is a risky procedure that involves a lengthy and expensive hospital stay that may not be covered by the patient's health insurance. The best place to have a bone marrow transplant is at a comprehensive cancer center or other facility that has the technical skill and experience to perform it safely.

Bone scan: A nuclear medicine imaging method that gives important information about the bones, including the location of cancer that may have spread to the bones. It can be done as an outpatient procedure and is usually painless, except for the needle stick when a low-dose radioactive substance is injected into a vein. Images are taken to see where the radioactivity accumulates, indicating an abnormality.

Bone (skeletal) survey: X-ray imaging of the entire skeleton.

Bracytherapy: A technique that involves placing radioactive substances directly into body tissue next to the cancer.  Bracytherapy is currently being developed to use on breast cancer patients. Also called internal radiation.

Brain scan: A nuclear medicine imaging method used to find abnormalities in the brain, including brain cancer and cancer that has spread to the brain from other places in the body. This procedure can be done in an outpatient clinic. It is painless, except for the needle stick when a radioactive substance is injected into a vein. The images taken will show where radioactivity accumulates, indicating an abnormality.

BRCA1: Breast Cancer Gene 1. A gene which, when damaged (mutated), places a woman at greater risk of developing breast and/or ovarian cancer, compared with women who do not have the mutation. In a woman with a BRCA1 mutation, the estimated lifetime risk of developing breast cancer is about 50% compared with about 12% in the general population. A person who has this mutated gene has a 50% chance of passing on the gene to each of her children. A genetic test is available, but it is recommended only for women who are known to be at risk because several women in their family have had breast or ovarian cancer at an early age (before menopause).  Any women considering the test should consider receiving genetic counseling.

BRCA2: Breast Cancer Gene 2.  A gene which, when damaged or mutated, puts the carrier at a higher risk for developing breast cancer and/or ovarian cancer than the general population. In a woman with a BRCA2 mutation, the estimated lifetime risk of developing breast cancer is 50% - 60%. BRCA2 and BRCA1 together account for about 80% of the breast cancers that occur in women with strong family histories of the disease. BRCA2 is also thought to raise the risk for breast cancer in men. A genetic test for BRCA2 is available but is only recommended for women or men with strong family histories of breast or ovarian cancer.  Any women considering the test should consider receiving genetic counseling.

Breast augmentation surgery: Surgery to increase the size of the breast(s).  Also called augmentation mammoplasty.

Breast biopsy: The removal of breast cells for pathological examination. A breast biopsy is performed to determine whether a suspicious area of the breast is cancerous or benign. 

Breast cancer: Cancer that originates in the breast. The main types of breast cancer are ductal carcinoma in situ, invasive ductal carcinoma, invasive lobular carcinoma, medullary carcinoma, and Paget’s disease of the nipple. Lobular carcinoma in situ (LCIS) is sometimes considered to be a type of breast cancer, but most breast specialists feel LCIS is a marker for increased breast cancer risk, and not a true cancer. (See definitions of these terms).

Breast compression: The flattening of the breast so that the maximum amount of tissue can be imaged and examined during mammography.

Breast conservation therapy: Also called lumpectomy; the surgical removal of a cancerous breast lump and a small amount of non-cancerous tissue around the lump, without removing any other part of the breast.  The method may or may not require an axillary dissection. Breast conservation therapy is usually followed by at least six weeks of radiation. (See also lumpectomy and radiation therapy).

Breast density: Describes breast tissue that has many glands close together. Density shows up as a white area on a mammogram film. Though fairly common (especially in younger women), dense breasts may make microcalcifications and many other masses difficult to detect.

Breast expander: A device used to stretch the remaining breast skin after a mastectomy. A breast expander is similar to a balloon, and the surgeon will fill the expander with salt-water solution periodically (usually once a week). The expansion process typically takes three to four months. After the skin is sufficiently stretched, the surgeon will replace the expander with a permanent breast implant. Also called tissue expander.

Breast-feeding: Giving a baby milk from the breast.  Also called suckling or nursing.

Breast implant:  A manufactured sac that is filled with silicone gel (a synthetic material) or saline (sterile saltwater). The sac is surgically inserted to increase breast size or restore the contour of a breast after mastectomy (breast removal). Because of concern about possible (but unproven) side effects of silicone, silicone implants are presently available only to women who agree to participate in a clinical trial in which side effects are carefully monitored.

Breast lift surgery: See mastoplexy.

Breast pain:Cyclic or non-cyclic pain in the breast or in the axilla (underarm) region of the body.   Approximately 15% of women with breast pain require treatment.  Breast pain is not usually (but can be) associated with breast cancer.  Also called mastalgia.

Breast prosthesis: An external breast form.  Some women wear prostheses after mastectomy (breast removal).  Many prostheses resemble the body's own weight and touch.

Breast reconstruction: Surgery that rebuilds the breast contour after mastectomy. A breast implant or the woman's own tissue provides the contour. If desired, the nipple and areola may also be re-created. Reconstruction can usually be done at the time of mastectomy or any time later. (See also mammoplasty).

Breast reduction surgery: Surgery to reduce the size of the breast(s).  Also called reduction mammoplasty.

Breast repositioning: See mastoplexy.

Breast self-examination (BSE): A technique of checking one's own breasts for lumps or suspicious changes. The method is recommended for all women over age 20, to be done once a month.  It is recommended that pre-menopausal women perform BSE the week after menstruation when the breasts are typically least tender.

Breast specialist A term describing health care professionals who have a dedicated interest in breast health. While they may acquire specialized knowledge in this area, medical licensing boards do not certify a specialty in breast care.

Updated: August 2006