Words to Know

ER-PR-HER2/neu-

Describes breast cancer cells that do not have estrogen receptors, progesterone receptors, or large amounts of HER2/neu protein. Also called ER-negative PR-negative HER2/neu-negative and triple-negative breast cancer.

ER-

Also called estrogen receptor-negative. Describes cells that do not have a protein to which the hormone estrogen will bind. Cancer cells that are ER- do not need estrogen to grow and usually do not stop growing when treated with hormones that block estrogen from binding.

ER

Also called estrogen receptor. A protein found inside the cells of the female reproductive tissue, some other types of tissue and some cancer cells. The hormone estrogen will bind to the receptors inside the cells and may cause the cells to grow.

eribulin mesylate

A medicine used to treat metastatic breast cancer in individuals who have already been treated with other chemotherapy. It is also being studied in the treatment of other types of cancer. Eribulin mesylate may block cancer cell growth by stopping cell division. It belongs to the family of medicines called antitubulin agents. Also called E7389 and Halaven.

erythema

Redness of the skin.

estradiol

A form of the hormone estrogen.

estrogen

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the lab. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.

estrogen blocker

A substance that keeps cells from making or using estrogen, a hormone that plays a role in female sex characteristics, the menstrual cycle, and pregnancy. Estrogen blockers may stop some cancer cells from growing and are used to prevent and treat breast cancer. They are also being studied in the treatment of other types of cancer. An estrogen blocker is a type of hormone antagonist. Also called antiestrogen.

estrogen receptor test

A lab test to find out if breast cancer cells have estrogen receptors, proteins to which estrogen will bind. If the cells have estrogen receptors, they may need estrogen to grow, and this may affect how the cancer is treated.

estrogen receptor-negative

Also called ER- or ER negative. Describes cells that do not have a protein to which the hormone estrogen will bind. Breast cancer cells that are estrogen receptor-negative do not need estrogen to grow and usually do not stop growing when treated with hormones that block estrogen from binding.

estrogen receptor-positive

Also called ER+ or ER positive. Describes cells that have a receptor protein that binds the hormone estrogen. Breast cancer cells that are estrogen receptor-positive may need estrogen to grow and may stop growing or die when treated with substances that block the binding and actions of estrogen.

estrogen replacement therapy

Also called ERT. Hormones given to postmenopausal women or to women who have had their ovaries surgically removed. Hormones are given to replace the estrogen no longer produced by the ovaries.

estrogen receptor

Also called ER. A protein found inside the cells of the female reproductive tissue, some other types of tissue and some breast cancer cells. The hormone estrogen will bind to the receptors inside the cells and may cause the cells to grow.

etanidazole

A medicine that increases the effectiveness of radiation therapy.

etidronate

Brand name, Didronel. A medicine that belongs to the family of medicines called bisphosphonates. Bisphosphonates are used as treatment for hypercalcemia (abnormally high levels of calcium in the blood) and for pain caused by breast cancer that has spread to the bone (bone metastases).

everolimus

Brand names Afinitor and Zortress. Everolimus is FDA approved to treat postmenopausal women with metastatic, hormone-positive breast cancer in combination with exemestane (Aromasin). Everolimus stops cancer cells from dividing and may block the growth of new blood vessels that tumors need to grow. It also decreases the body's immune responses. It is a type of antiangiogenesis agent and a type of immunosuppressant. Also called RAD001.

Evista

A medicine used to reduce the risk of invasive breast cancer in postmenopausal women who are at high risk of the disease or who have osteoporosis. It is also used to prevent and treat osteoporosis in postmenopausal women. It is being studied in the prevention of breast cancer in certain premenopausal women and in the prevention and treatment of other conditions. Evista blocks the effects of the hormone estrogen in the breast and increases the amount of calcium in bone. It is a type of selective estrogen receptor modulator (SERM). Also called raloxifene hydrochloride.

excision

Removal by surgery.

excisional biopsy

A surgical procedure in which an entire lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

exemestane

Also called Aromasin. A medicine used to treat advanced breast cancer and to prevent recurrent breast cancer in postmenopausal women who have already been treated with tamoxifen. It is also being studied in the treatment of other types of cancer. Exemestane causes a decrease in the amount of estrogen made by the body. It is a type of aromatase inhibitor.