BREAST CANCER MEDICATION

A recent analysis of a subset of the Nurses' Health Study data indicated that Aspirin may reduce mortality from breast cancer

Hormone blocking therapy: Some breast cancers require estrogen to continue growing. They can be identified by the presence of estrogen receptors (ER+) and progesterone receptors (PR+) on their surface (sometimes referred to together as hormone receptors). 

These ER+ cancers can be treated with drugs that either block the receptors, e.g. tamoxifen (Nolvadex), or alternatively block the production of estrogen with an aromatase inhibitor, e.g. anastrozole (Arimidex) or letrozole (Femara). Aromatase inhibitors, however, are only suitable for post-menopausal patients.

There are currently three main groups of medications used for adjuvant breast cancer treatment: hormone blocking therapy, chemotherapy, and monoclonal antibodies

Chemotherapy: Predominately used for stage 2-4 disease, being particularly beneficial in estrogen receptor-negative (ER-) disease. They are given in combinations, usually for 3–6 months. One of the most common treatments is cyclophosphamide plus doxorubicin (Adriamycin), known as AC.

Most chemotherapy medications work by destroying fast-growing and/or fast-replicating cancer cells either by causing DNA damage upon replication or other mechanisms; these drugs also damage fast-growing normal cells where they cause serious side effects. 

Damage to the heart muscle is the most dangerous complication of doxorubicin. Sometimes a taxane drug, such as docetaxel, is added, and the regime is then known as CAT; taxane attacks the microtubules in cancer cells.

Another common treatment, which produces equivalent results, is cyclophosphamide, methotrexate, and fluorouracil (CMF). (Chemotherapy can literally refer to any drug, but it is usually used to refer to traditional non-hormone treatments for cancer.)

Monoclonal antibodies: A relatively recent development in HER2+ breast cancer treatment. Approximately 15-20 percent of breast cancers have an amplification of the HER2/neu This receptor is normally stimulated by a growth factor which causes the cell to divide; in the absence of the growth factor, the cell will normally stop growing. Overexpression of this receptor in breast cancer is associated with increased disease recurrence and worse prognosis. Trastuzumab (Herceptin), a monoclonal antibody to HER2, has improved the 5 year disease free survival of stage 1–3 HER2+ breast cancers to about 87% (overall survival 95%). Trastuzumab, however, is expensive, and approx 2% of patients suffer significant heart damage; it is otherwise well tolerated, with far milder side effects than conventional chemotherapy. Other monoclonal antibodies are also undergoing clinical trials. gene or overexpression of its protein product.