In chemotherapy, medicine that hinders the ability of the cancer cells to divide and reproduce is applied. In effect, the cells cannot divide rapidly, thus preventing the cancer from spreading. But because this is a systemic type of treatment, cancer cells are not the only ones affected by the medicine. That is why it is normal that one would experience side effects such as nausea and hair loss, because the cells in these organs are affected as well.
Different women have different treatment plans. The regimen is based on what we call breast cancer factors such as tumor size, lymph node involvement, and others. Doctors may recommend a series of chemotherapies depending on these factors.
Other treatments such as immune therapy and anti-angiogenesis therapies, while currently not widely available, are still being studied on. At present, an immune therapy called Herceptin is available. But this treatment is only for advanced breast cancer cases, and with an overactive HER2/neu cancer gene. In a few years, with more research, vaccines and immunity treatments may become available.