Effect of preoperative chemotherapy on local-regional disease in women with operable breast cancer: findings from National Surgical Adjuvant Breast and Bowel Project B-18.

Preoperative therapy reduced the size of most breast tumors and decreased the incidence of positive nodes. The greatest increase in lumpectomy after preoperative therapy occurred in women with tumors > or = 5 cm, since women with tumors less than 5 cm were already lumpectomy candidates. Preoperative therapy should be considered for the initial management of breast tumors judged too large for lumpectomy.