Oncologist: A doctor specially trained in cancer treatment.

OncotypeDX: A specific commercial test using genetic properties of your tumor that allows a statistical 'risk of recurrence' to be calculated. It assists in determining whether chemotherapy will be helpful in reducing recurrence.

Paget's Disease: Breast cancer arising just beneath the nipple. It is harder to detect in this site.

Palliative Care: Care directed only at relieving symptoms (pain, nausea, shortness of breath, cough, hiccough, loneliness, etc).

Palliative Surgery: Surgery undertaken toward the same end, usually to relieve pain, bowel obstruction, or shortness of breath.

Partial Mastectomy: See "Breast Conservation Surgery".

Port: A "reservoir" with a catheter going into a large vein which is placed under the skin near the collarbone and accessed through the skin. Its use avoids damaging arm veins with chemotherapy.

Postmenopausal: After your ovaries stop high hormone production, usually marked by the cessation of menstrual periods if you have NOT had a hysterectomy.

Radiation Therapy: Using radiation to treat or palliate cancer. See "External beam radiation".

Reconstructive Surgery: Cosmetic restoration of breast size and appearance. See "Breast Reconstruction".

Sclerosing Adenosis: A benign condition where-in the breast reacts to abnormal gland proliferation. It can look like cancer on a mammogram, and it indicates a higher risk of later having cancer.

Sentinel Lymph Node Biopsy: A technique in which a radioactive tracer & a blue dye is injected near the tumor. The material is carried to the lymph nodes. The first node capturing the tracer is most likely to have any cancer, if it has spread. If there is none, the remaining nodes do NOT need to be removed.

Staging: A categorization of the extent to which a cancer has grown and spread, used to determine treatment, and the statistical results of varying treatment plans.

Staging Surgery: Surgery preformed to "stage" the disease. The surgery itself does not improve the patients condition, but the outcome of surgery will affect the treatment plan chosen.

Stereotactic Breast Biopsy: A method which uses computerized x-ray images to determine the exact location of a shadow which cannot be felt so that a biopsy of that area can accurately be preformed.

Synchronous Tumors: Similar, but independent, tumors arising at the same time. See "multifocal".

Tamoxifen: A medication which diminishes the amount of estrogen produced by the body to treat an "estrogen-sensitive" cancer, or to prevent its occurrence in high-risk women.

Trastuzumab: A medication which "blocks" the HER2 site on the cell surface used to treat those breast cancers which are "overexpressing" HER2.

Tumor: Any solid growth in the breast. It may or may not be cancer. Most tumors are NOT cancerous.

Tumor Markers: Characteristics of a tumor which indicate its "aggressiveness" such as receptivity to estrogen (ER) or progesterone (PR), how rapidly it is dividing (S-phase fraction, Ki-67), how unusual the nucleus looks (nuclear grade), how abnormal its DNA is (flow cytometry), and if it overexpresses HER2.