Adjuvant therapy: Treatment provided in addition to surgical treatment, given when all detectable disease has been removed, but where there remains a risk of relapse due to occult disease. Examples of adjuvant therapy include radiation therapy, chemotherapy and hormonal therapy.

Anemia: A condition that occurs when there is a decrease in red blood cells, or there is not enough hemoglobin in a person’s blood. Hemoglobin is a substance in the red blood cells that enables the blood to transport oxygen through the body.

Areola: The pigmented area of skin that surrounds the nipple.

Aromatase inhibitor: A class of drugs that either decreases the production of estrogen or blocks the action of estrogen on receptors. They are used as hormonal therapy in post-menopausal patients that have estrogen receptor positive breast cancer.

Aspiration: Removal of fluid from a lump, often a cyst, with a needle.

Atypical hyperplasia: A benign (non-cancerous) condition in which breast tissue has certain abnormal features. This condition increases the risk of breast cancer.

Axilla: The underarm.

Benign tumor: A non-cancerous growth that does not spread to nearby tissues or other parts of the body.

Biological therapy: Treatment to stimulate or restore the ability of the immune system to fight infection and disease, also called immunotherapy. Therapeutic antibodies can be given as drugs, and the patient’s immune system is recruited to destroy tumor cells by the therapeutic antibodies.

Biopsy: The removal and examination of a sample of tissue with a microscope to see whether cancer cells are present.

BRCA genes: BRCA 1 and BRCA 2 genes are genes that prevent the formation of tumors. Mutations in these genes predispose patients to the development of breast and ovarian cancers.

Breast surgeons: General surgeons who dedicate all or part of their practice to the treatment of breast disease.

Cancer: A general term for more than 100 diseases in which there is an uncontrolled, abnormal growth of cells. Cancer cells can spread locally and through the bloodstream and lymphatic system to other parts of the body.

Carcinoma: Tumor tissue derived from epithelial lining cells that have been altered to such an extent that the cells become transformed and exhibit abnormal malignant properties.

Carcinoma in situ: An early form of cell proliferation defined by the absence of invasion of tumor cells into the surrounding tissue.

Chemotherapy: Treatment with anticancer drugs. Chemotherapy may be given after breast surgery to patients with breast cancer to kill any microscopic cancer cells within the remaining breast tissue or in the rest of the body. Occasionally, the surgeon and medical oncologist may recommend chemotherapy prior to breast surgery to decrease the size of the tumor.

Clear margin: An area of normal tissue that surrounds cancerous tissue, as seen during the microscopic examination of a biopsy or surgical specimen.

Clinical trial: A set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions.

Colony stimulating factors: Laboratory-made substances similar to substances in the body that stimulate the production of blood cells. Treatment with colony-stimulating factors can help cells in the bone marrow recover from the effects of chemotherapy.

Computed axial tomography (CAT scan): A 3-dimensional image of a cross-section of the body created with X-rays and computer processors.

Cyst: A closed sac filled with fluid.

Duct: A tube in the breast through which milk passes from the lobules to the nipple.

Ductal carcinoma in situ (or intraductal carcinoma): Cancer that remains localized in the ducts of the breast and has not spread beyond them into the surrounding tissue.

Erythrocytes: Red blood cells that carry oxygen from the lungs to cells in all parts of the body. Erythrocytes also carry carbon dioxide from the cells back to the lungs.

Estrogen: The primary female sex hormone. Estrogens are made in the body and are also used as part of some oral contraceptives and in estrogen replacement therapy for postmenopausal women.

Estrogen receptor test: Lab test used to determine if breast cancer cells have estrogen receptors. If the cells have estrogen receptors, they may need estrogen to grow, and this may affect how the cancer is treated. It is noted as estrogen receptor-positive or -negative.

Gene: The basic unit of heredity found in living organisms. It is a name given to some stretches of DNA or RNA. Genes hold the information to build and maintain cells and pass genetic traits to offspring.

Genetic counseling: The process by which patients or relatives at risk of an inherited disorder are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them to manage their risks.

Geneticist: A biologist who studies the science of genes. They evaluate, diagnose and manage patients with hereditary conditions, calculate risks and refer to other medical specialties for management and further evaluation.

Gynecologist: A doctor who specializes in the care and health of the female reproductive organs.

HER2neu receptor: Receptor noted on breast cancer cells. Amplification or over-expression of this gene has been shown to play an important role in the pathogenesis and progression of certain aggressive types of breast cancer. In recent years it has evolved to become an important biomarker and target of therapy for the disease.

Hormonal therapy: Involves manipulation of the endocrine system to inhibit cellular growth by blocking hormone receptors or estrogen production.

Hormones: Chemicals produced by glands in the body. Hormones control the actions of certain cells or organs.

Hormone receptor test: A test used to measure the amount of certain proteins, called hormone receptors, in breast cancer tissue. Hormones can attach to these proteins. A high level of hormone receptors means hormones probably help the cancer grow.

Immune system: The body’s natural defense system against infection or disease.

Implant: A silicone gel-filled or saline-filled sac inserted above or below the chest muscles to restore breast shape.

Intraductal carcinoma: See ductal carcinoma in situ.

Leukocytes: White blood cells that protect the body against infections and foreign material.

Leukopenia: A decreased white blood cell count, which places individuals at increased risk of infection.

Lobe: The glandular milk producing tissue of the breast. The breast contains 14-18 lactiferous lobes that converge to the nipple through ducts.

Lobule: Smaller divisions of tissue located inside the main lobes, where milk is produced.

Lobular carcinoma in situ: Proliferation of lobular cells within the lobules which serves as a marker for the increased risk of developing breast cancer anywhere in either breast. It is not considered a cancer, but can indicate a risk of future cancer.

Local therapy: Treatment that affects cells in the tumor and the area close to it.

Localized cancer: Cancer that has not spread to other parts of the body.

Lumpectomy: Surgery to remove only the cancerous breast lump. It is usually followed by radiation therapy, serving to preserve the natural appearance of the breast.

Lymph: Fluid that travels throughout the lymphatic system, returning protein and fluid to the circulation, bringing bacteria to lymph nodes where they are destroyed and sometimes transporting metastatic cancer cells, if present, to other parts of the body.

Lymphatic system: Part of the circulatory system that includes an extensive network of lymph vessels and lymph nodes. The lymphatic system returns lymph to the heart and plays an important part in the immune system’s function to protect the body from foreign substances.

Lymphedema: An abnormal buildup of fluid that causes swelling, most often in the arms or legs. Lymphedema develops when lymph vessels are missing, impaired, damaged, or removed. This condition can be chronic and irreversible.

Magnetic resonance imaging (MRI): A 3-dimensional view of tissues that uses a magnet and no radiation to visualized detailed internal structures. It is a highly sensitive tool for detecting breast cancer.

Malignant: Cancerous; grows, invades, and can spread to other parts of the body.

Mammogram: A series of X-rays of the breast used to detect abnormal growths or changes in the breast tissue.

Mastectomy: Surgery to remove the breast.

Metastasize: To spread from one part of the body to another. When cancer cells metastasize and cause secondary tumors, the cells in the secondary tumor are like those in the original cancer.

Microcalcifications: Tiny deposits of calcium that cannot be felt but can be detected on a mammogram. A cluster of these small specks of calcium may indicate that an early cancer is present, but often are benign.

Oncologist, medical: A physician who specializes in the medical treatment of cancer. Medical oncologists have a thorough knowledge of how cancers behave and grow. This knowledge is used to calculate your risk of recurrence as well as the possible need for and benefits of additional or adjuvant therapy (such as chemotherapy and hormonal therapy). Your medical oncologist generally manages your overall medical care and monitors your general health during your course of treatment. He or she checks your progress frequently, reviews your lab and X-ray results, and coordinates your medical care before and after your course of treatment.

Oncologist, radiation: A physician trained in cancer treatment using radiation therapy.

Oncologist, surgical: A physician who focuses on the surgical management of cancer.

Palpation: A simple technique in which a doctor presses on the surface of the body to feel the organs or tissues underneath.

Pathologist: A physician who specializes in analyzing breast tissue samples to determine if cancer cells are present, whether the cancer is localized or has the potential to spread, and whether the cancer exhibits specific receptors and proteins which help to guide treatment.

Plastic surgeon: A surgeon who specializes in breast reconstructive techniques to restore breast shape after mastectomy.

Platelet:: S:Female sex hormone involved in the female menstrual cycle, pregnancy and embryogenesis.te of an injury.

Progesterone - Female sex hormone involved in the female menstrual cycle, pregnancy and embryogenesis.

Prognosis: The likely outcome or course of an illness.

Prosthesis: An artificial replacement of a part of the body. A breast prosthesis is a breast form worn under clothing.

Raloxifene: An oral selective estrogen receptor modulator that has estrogenic effects on bone and anti-estrogenic actions on the uterus and breast. It is used in the prevention of osteoporosis in postmenopausal women and prevention of breast cancer in postmenopausal women at increased risk for the disease.

Radiation therapy: A form of cancer treatment that uses high levels of radiation to kill cancer cells or keep them from growing and dividing, while minimizing damage to healthy cells.

Remission: The state of absence of disease activity in patients known to have a chronic illness that cannot be cured.

Risk factor: A variable that increases a person’s chance of developing a disease.

Sentinel lymph node:The first lymph node to which a tumor drains, making it the first place where cancer is likely to spread. In breast cancer, the sentinel node is usually located in the axillary nodes under the arm.

Silicone: A synthetic gel that is used as the outer coating on breast implants. It also makes up the inside filling of some implants, although saline is now a more common implant filler.

Stage: The extent of the cancer. The stage of breast cancer depends on the size of the cancer and whether it has spread from its original site to lymph nodes or to other parts of the body.

Systemic therapy: Treatment that reaches cells all over the body.

Tamoxifen: A hormonal estrogen blocking therapy used to treat estrogen-sensitive breast cancer and to prevent breast cancer in women who are at increased risk for breast cancer.

Thermography: A test to measure and display heat patterns of tissues near the surface of the breast. Abnormal tissue generally is warmer than healthy tissue. This technique is under study; its value in detecting breast cancer has not been proven.

Tumor: An abnormal mass of tissue.

Ultrasonography: A test in which high-frequency sound waves, inaudible to the human ear, are transmitted through body tissues. The echoes are recorded and transformed into video or photographic images. Ultrasound is used to create images of soft tissue structures and can also detect blockages in the blood vessels. Ultrasound images help in the diagnosis of a wide range of diseases and conditions. It can help determine whether a lump is cystic or solid, and if solid, suspicious for malignancy or benign appearing.

X-ray: High-energy radiation used in low doses to diagnose diseases and used in high doses to treat cancer.

Last reviewed by a Cleveland Clinic medical professional on 04/10/2012.

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