NSABP breast cancer clinical trials: recent results and future directions.

Over the past 40 years, the National Surgical Adjuvant Breast and Bowel Project (NSABP) has conducted several large, randomized clinical trials evaluating various aspects of surgical and adjuvant therapy in patients with operable breast cancer. Results from these trials have contributed significantly in reducing the extent of surgical procedures and in improving the outcome of patients with early-stage breast cancer. Furthermore, they have helped to establish standards of care for the surgical management of invasive and non-invasive disease and for the use of adjuvant hormonal therapy and adjuvant chemotherapy for patients with negative as well as for those with positive axillary nodes. More recent trials are evaluating several new classes of promising drugs such as the aromatase inhibitors in postmenopausal women with invasive or intraductal breast cancer, the taxanes for patients with positive nodes and in the neoadjuvant setting and other targeted molecular therapies such as trastuzumab and bisphosphonates. Results from these ongoing and recently completed trials could improve outcomes and quality of life for patients with early-stage breast cancer.