Glossary of Terminology

The Abramson Cancer Center of the University of Pennsylvania
Last Modified: January 22, 2002

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Adjuvant Therapy

Treatment that is added to increase the effectiveness of a primary therapy. It usually refers to hormonal therapy, chemotherapy, or radiation added after surgery to increase the chances of curing the disease or keeping it in check.


A substance (for example, the drug tamoxifen) that blocks the effects of estrogen on tumors. Antiestrogens are used to treat breast cancers that depend on estrogen for growth.

Axillary Dissection

A surgical procedure in which the lymph nodes in the armpit (axillary nodes) are removed and examined to find out if breast cancer has spread to those nodes and to remove any cancerous lymph nodes.


A tissue sample, examined under the microscope.

Breast Conservation Therapy

Surgery to remove a breast cancer and a small amount of benign tissue around the cancer, without removing any other part of the breast. This procedure is also called lumpectomy, segmental excision, or limited breast surgery. The method may require an axillary dissection and usually requires radiation therapy in addition to the breast conservation surgery.

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 be done at the time of mastectomy or any time later.

Carcinoma in Situ

An early stage of cancer, in which the tumor is still only in the structures of the organ where it first developed, and the disease has not invaded other parts of the organ or spread (metastasized). Most in situ carcinomas are highly curable.


Treatment with drugs to destroy cancer cells. Chemotherapy is often used in addition to surgery or radiation to treat cancer when metastasis is proven or suspected, when the cancer has come back (recurred), or when there is a strong likelihood that the cancer could recur.


A fluid-filled mass that is usually benign. The fluid can be removed for analysis.


A hollow passage for gland secretions. In the breast, a passage through which milk passes from the lobule (which makes the milk) to the nipple.

Ductal Carcinoma in Situ

The most common type of non-invasive breast cancer. Cancer cells have not spread beyond the ducts.


A female sex hormone produced primarily by the ovaries and in smaller amounts by the adrenal cortex. In women, levels of estrogen fluctuate on nature's carefully orchestrated schedule, regulating the development of secondary sex characteristics, including breasts, regulating the monthly cycle of menstruation; and preparing the body for fertilization and reproduction. In breast cancer, estrogen may promote the growth of cancer cells.


A type of benign breast tumor composed of fibrous tissue and glandular tissue. On clinical examination or breast self-examination, it usually feels like a firm, round, smooth lump. These usually occur in young women.

Fibrocystic Changes

A term that describes certain benign changes in the breast; also called fibrocystic disease. Symptoms of this condition are breast swelling or pain. Signs that a health care professional can observe on clinical breast examination are the presence of nodularity (nodules), lumpiness, and sometimes, nipple discharge. Because these signs sometimes mimic breast cancer, diagnostic mammography or microscopic examination of breast tissue may be needed to show that there is no cancer.


Formation of fibrous (scar-like) tissue. This can occur anywhere in the body.


A gene that produces a type of receptor that helps cells grow. Breast cancer cells with too many Her-2/new receptors tend to be exceptionally fast-growing.


A chemical substance released into the body by the endocrine glands, such as the thyroid, adrenal, or ovaries. The substance travels through the bloodstream and sets in the motion various body functions. For example, prolactin, which is produced in the pituitary gland, begins and sustains the production of milk in the breast after childbirth.

Hormone Receptor Assay

A test to see whether a breast tumor is likely to be affected by hormones or if it can be treated with hormones.

Hormone Therapy

Treatment with hormones, drugs that interfere with hormone production or hormone action, or surgical removal of hormone-producing glands to kill cancer cells or show their growth. The most common hormonal therapy for breast cancer is the drug tamoxifen. Other hormonal therapies include megestrol, aminoglutethimide, androgens and surgical removal of the ovaries (oophorectomy).

Intraductal Papillomas

Small, finger-like, polyp-like, noncancerous growths in the breast ducts that may cause a bloody nipple discharge. These are most often found in women 45 to 50 years of age. When many papillomas exist, breast cancer risk is slightly increased.

Latissimus Dorsi Flap Procedure

A method of breast reconstruction that uses the long flat muscle of the back, by rotating it to the chest area.

Lobular Carcinoma in Situ

(LCIS) refers to abnormal cells lining a gland in the breast. This is a risk factor for the future development of cancer, but this is not felt to represent a cancer itself.


Surgery to remove the breast tumor and a small amount of surrounding normal tissue.

Lymph Nodes

Small bean-shaped collections of immune system tissue such as lymphocytes, located along lymphatic vessels. They remove waste and fluids from lymph and help fight infections. Also called lymph glands.


An infrequent complication after breast cancer treatment. Swelling in the arm caused by excess fluid that collects after lymph nodes and vessels are removed by surgery or treated by radiation. This condition is usually persistent although not painful.


Removal of the entire breast. In a simple or total mastectomy surgeons do not cut away any lymph nodes or muscle tissue; in a modified radical mastectomy, surgeons remove the breast and some armpit lymph nodes; in a radical mastectomy (now rarely performed) surgeons remove the breast, armpit lymph nodes, and chest wall muscles under the breast.


The time in a woman's life when monthly cycles of menstruation cease forever and the level of hormones produced by the ovaries decreases. Menopause usually occurs in the late 40s or early 50s, but it can also be caused by surgical removal of both ovaries (oophorectomy), or by some chemotherapies that destroy ovarian function.


The spread of cancer cells to distant areas of the body by way of the lymph system or bloodstream.

Neoadjuvant Therapy

Systemic therapy, such as chemotherapy or hormone therapy, given before surgery. Adjuvant therapy can shrink some breast cancers, so that surgical removal can be accomplished with a less extensive operation that would otherwise be needed.

Nodal Status

Indicates whether a breast cancer has spread (node-positive) or has not spread (node-negative) to lymph nodes in the armpit (axillary nodes). The number and site of positive axillary nodes can help predict the risk of cancer recurrence.


Surgery to remove the ovaries.


Reproductive organ in the female pelvis. Normally a woman has two ovaries. They contain the eggs (ova) that, when joined with sperm, result in pregnancy. Ovaries are also the primary source of estrogen.


Using the hands to examine. A palpable mass in the breast is one that can be felt.


A female sex hormone released by the ovaries during every menstrual cycle to prepare the uterus for pregnancy and the breasts for milk production (lactation).


A prediction of the course of disease; the outlook for the cure of the patient. For example, women with breast cancer that was detected early and received prompt treatment have a good prognosis.

Sentinel Node Biopsy

In a sentinel lymph node biopsy, the surgeon injects a radioactive substance and/or blue dye into the area around the tumor. Lymphatic vessels carry these materials to the sentinel lymph node (also called the sentinel node). The doctor can see the blue dye or detect the radioactivity (with a geiger counter) in the sentinel node, which is cut out and examined. If the sentinel node contains cancer, more axillary lymph nodes are removed. But, if it is free of cancer, the patient can avoid additional axillary surgery and its potential side effects.

S-Phase Fraction (SPF)

The percentage of cells that are replicating their DNA. DNA replication usually indicates that a cell is getting ready to split into two new cells. A low SPF is a sign that a tumor is slow-growing; a high SPF shows that the cells are dividing rapidly and the tumor is growing quickly.


Indicate how far a breast cancer has spread.

Stereotactic Needle Biopsy

A method of needle biopsy that is useful in some cases in which calcifications or a mass can been seen on mammogram but cannot be located by touch. Computerized equipment maps the location of the mass and this is used as a guide for the placement of the needle.

Supportive Care

Measures taken to relive symptoms and improve quality of life, but not expected to destroy the cancer. Pain medication is an example of supportive care.

Systemic Therapy

Treatment that reaches and affects cells throughout the body; for example, chemotherapy.

Tamoxifen (Brand Name: Nolvadex)

This drug blocks the effects of estrogen on many organs, such as the breast. Blocking estrogen is desirable in some cases of breast cancer because estrogen promotes their growth. Recent research suggests that tamoxifen may lower the risk of developing breast cancer in women with certain risk factors.

Transverse Rectus Abdominus Muscle Flap Procedure

A method of breast reconstruction in which tissue from the lower abdominal wall which receives its blood supply from the rectus abdominus muscle is used. The tissue from this area is moved up to the chest to create a breast mound and usually does not require an implant. Moving muscle and tissue from the lower abdomen to the chest results in flattening of the lower abdomen (a "tummy tuck"). Also called a TRAM flap or rectus abdominus flap procedure.


High frequency sound waves used to produce images of the breast.

For a more comprehensive glossary, you may access the ACS web site at


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