Systemic treatment for stage I and stage II breast cancer

Breast cancer presents as two interrelated problems. The first is disease in the breast and axillary lymph nodes and the second is metastatic spread to distant sites. Local diseases can be controlled with less morbidity than in the past because of advances in surgery and radiotherapy. In addition, heightened public awareness and the more widespread use of mammography have increased the detection of smaller cancers that have a better prognosis and are easier to treat. The problem of late relapse leading to death, however, motivates continued intensive study of systemic therapy as treatment for the undetectable micrometastatic disease remaining after surgery. Currently, hormonal therapy and chemotherapy are known to prolong disease-free and overall survival in nearly all groups of patients, although the relative and absolute influences of drug therapies are modest and vary among patient subgroups, and the proper application of these treatments to the hundreds of thousands of patients diagnosed worldwide per year could have a major impact on public health. For the future, clinical trials and laboratory advances indicate that novel dosing and scheduling of chemotherapy agents combined with newer modalities may provide even greater impact against occult disseminated disease.