Sparano JA et al. (2008) Weekly paclitaxel in the adjuvant treatment of breast cancer. N Engl J Med 358: 1663–1671

Adding adjuvant taxane therapy to an anthracycline-containing chemotherapy regimen has been shown to reduce the risks of disease recurrence and death in women with operable breast cancer. Sparano and co-workers investigated the optimum adjuvant taxane agent and administration schedule in this setting and found that weekly adjuvant paclitaxel therapy after doxorubicin and cyclophosphamide chemotherapy improves both disease-free and overall survival in women with breast cancer.

This study enrolled 4,950 women with operable, histologically confirmed axillarylymph-node-positive or high-risk, axillary-lymph-node-negative breast cancer. All participants were assigned to receive doxorubicin (60 mg/m2) and cyclophosphamide (600 mg/m2) once every 3 weeks for 4 cycles and were randomly assigned to receive weekly or 3-weekly paclitaxel (80 mg/m2 for 12 doses or 175 mg/m2 for 4 doses, respectively) or docetaxel (35 mg/m2 for 12 doses or 100 mg/m2 for 4 doses, respectively).

Patients who received weekly paclitaxel had significantly better disease-free and overall survival than those who received the current standard therapy of 3-weekly paclitaxel (hazard ratio [HR] 1.27, P = 0.006 and HR 1.32, P = 0.01, respectively). The survival benefit conferred by weekly paclitaxel was maintained in patients with HER2-negative disease, regardless of hormone-receptor status. Docetaxel administered once every 3 weeks improved disease-free survival, but not overall survival, compared with 3-weekly paclitaxel (HR 1.23, P = 0.02 and HR 1.13, P = 0.25, respectively) but did not significantly improve either survival outcome compared with standard therapy when administered weekly. The weekly paclitaxel group had a significantly higher incidence of moderate to severe neuropathy than any other treatment group (P <0.001 for all comparisons).