Classes of Drugs

Chemotherapy drugs for non-metastatic and metastatic breast cancer fall into several categories.

• Alkylators affect cancer cells much like radiation does: by damaging the proteins that control growth in the genes of the tumor cell. Cyclophosphamide (the "C" in CAF, CMF, CEF, and FAC) is the most commonly used alkylating agent. It can be given intravenously (IV) (in the veins) or orally (by mouth).
• Antimetabolites act as false building blocks in a cancer cell's genes, causing it to die as it gets ready to divide. Fluorouracil, or 5-FU, is an antimetabolite, as is Gemzar (chemical name: gemcitabine).
• Antibiotics (not to be confused with antibiotics that fight infection) include potent inhibitors of gene replication. ("Anti" means "against," and "biotic" means "growth.") Adriamycin is the most commonly used drug in this category, and is often combined with Cytoxan (cyclophosphamide). (Adriamycin belongs to a group of drugs called anthracyclines.)
• Antimiotic agents or natural agents rob cellular genes of the ability to reproduce themselves during division. One example of an antimiotic is vincristine (brand name: Oncovin), which comes from the periwinkle plant. Vinorelbine (brand name: Navelbine) comes from the same plant but is chemically altered in a way that reduces the side effects.
• Antimicrotubule or natural agents interfere with cell structure and cell division. Taxol (paclitaxel) and Taxotere (docetaxel), two examples of drugs from this group, are produced from the bark of the yew tree.