Calcifications: Deposits of the mineral calcium, found in the breast on mammography. They can be large (macrocalcifications) or tiny (microcalcifications) and are found more commonly in benign lesions. Some microcalcifications are a sign of cancer.

Carcinoma-In-Situ: A cancer which has not yet broken out of the duct or lobule in which it began. Since it has not spread beyond the breast at this point, it is nearly 100% curable.

Chemotherapy: Medications which help your body fight off cancer. They are infused into the blood (IV). Side effects such as alopecia and anorexia commonly accompany their use.

Core Needle Biopsy: The removal of a small cylinder of tissue by a large needle for examination. In contrast, a fine needle aspiration (FNA) removes only a number individual cells for exam. Neither removes the entire mass or tumor.

Diagnostic Surgery: One of several methods of obtaining tissue to diagnose a lesion. Fine needle aspiration, needle core biopsy, incisional biopsy, and excisional biopsy are the most common methods used.

Dimpling: A pucker or indentation of skin. It may be a sign of a lesion in the breast, which may be cancer.

Duct: A hollow passage (tube) for gland secretions, which, in the breast, is milk. Most breast cancers arise in the ducts.

Ductal Cancer: A cancer which began in a milk duct and not in a lobule. Most breast cancers (97%) are of the ductal variety. It is thought that nearly all begin as "ductal carcinoma-in-situ, termed "DCIS".

Ductal Carcinoma-in-situ (DCIS): See "Carcinoma-in-situ" and "Ductal Cancer" above.

Edema: Build up of fluid in the tissues causing swelling. It can occur in the arm after modified radical mastectomy, axillary dissection, or radiation therapy.

Epidermal Growth Factor (EGFR): A family of proteins on the cell surface which tell it when to divide.

Excisional Biopsy: The surgical removal of tissue for diagnosis. No significant margin of normal tissue is taken, but the entire lesion is removed.

External Beam Radiation: A carefully aimed beam of high-energy x-rays directed to the site of the cancer.

Fat Necrosis: Painless, firm lumps created when fatty tissue in the breast has its blood supply damaged by minor trauma or surgery.

Fibrocystic Changes: Generalized breast lumpiness caused over years by the effect of hormones which vary throughout the menstrual cycle.

Fibroadenoma: Common, benign tumors of the breast. They are usually firm, painless, smother, rubbery, and easily move-able.

Fine Needle Aspiration: Extraction of cells from a mass, for diagnosis, using a small needle & applying suction with a syringe.

Grade of Tumor: A measure of how similar, or dissimilar, your tumor is to normal breast cells. A "low grade" tumor is closer to the normal pattern and has a better prognosis. A "high grade" tumor is worse.