Adjuvant therapy approaches to breast cancer: should taxanes be incorporated?

The triplet of docetaxel, doxorubicin, and cyclophosphamide (TAC) has emerged as an alternative chemotherapy regimen for adjuvant management of node-positive breast cancer. Based on recently reported 3-year data from the Breast Cancer International Research Group (BCIRG) 001, disease-free survival was significantly higher in patients who underwent adjuvant chemotherapy with TAC rather than the established regimen of 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC). TAC reduced the risk of disease recurrence in estrogen receptor-positive and -negative patients. Whereas overall survival was not significantly different between the two groups, TAC led to a significant reduction in mortality in the subset of patients with one to three involved axillary lymph nodes. Overall, these interim BCIRG 001 results, coupled with those from Cancer and Leukemia Group B-9344 and National Surgical Adjuvant Breast and Bowel Project (NSABP) B-28 (phase III trials of sequential adjuvant chemotherapy with doxorubicin and cyclophosphamide followed by paclitaxel), suggest that taxanes are a valuable component of adjuvant chemotherapy for patients with node-positive breast cancer, including those with estrogen receptor positivity and/or extensive lymph node involvement. Accumulating data in the neoadjuvant setting lend further support to the view that the taxanes confer clinically meaningful benefits in the management of early-stage breast cancer. Such ongoing studies as NSABP B-30 will be instrumental in establishing the relative merits of sequential versus concurrent taxane-anthracycline adjuvant regimens for patients with node-positive breast cancer.