image for chemotherapy article There are four standard types of treatment for breast cancer: surgery, radiation therapy, chemotherapy, and hormone therapy. The type chosen in each case depends on the stage of the cancer and other factors that vary with each patient. Chemotherapy uses medications to stop the growth of cancer cells by killing the cells or stopping them from dividing. It may be used alone or with other types of treatment. Scientific knowledge about the effectiveness of chemotherapy comes only from careful clinical trials that compare different combinations and dosages of anti-cancer medications. In treating tumors of all sorts, effectiveness sometimes increases with higher drug dosages, but side effects are often significantly worse. A current focus in much oncology research is to identify treatments which maximize effectiveness and minimize complications.

Chemotherapy treatment for breast cancer began in the 1970s following the pioneering studies of the National Surgical Adjuvant Breast and Bowel Project and similar work by Italian scientists. Chemotherapy has been proven beneficial, but not often curative. For women at high risk for breast cancer relapse after surgery, scientists tried especially high doses of chemotherapy in hopes of achieving higher effectiveness than was possible from conventional, low-dose chemotherapy. This high dosage treatment is so strong that follow-up blood cell transplants are required to replenish bone marrow damaged during the treatment. In total, it’s estimated that over 15,000 women have had high-dose chemotherapy and blood cell transplants for the treatment of breast cancer.

Initial reports from the early 1990s suggested that the high-dose treatment was producing better results than conventional chemotherapy. Because of publicity given to these preliminary results, demand for high-dose treatment by patients and advocates increased. Some state legislatures mandated that insurance companies pay for this treatment.

By the late 1990s it became clear that randomized clinical trials, the most scientifically rigorous types of studies, were needed to prove whether the risks of high-dose chemotherapy were balanced by better results. This research was important because the high-dose chemotherapy was more difficult and toxic, thus causing worse side effects. It was also more expensive. In addition, researchers wanted to determine whether the results varied among patients by factors, such as the stage of the cancer.