Dose and dose intensity are determinants of outcome in the adjuvant treatment of breast cancer. The Cancer and Leukemia Group

Background: Both total dose and dose intensity of adjuvant chemotherapy are postulated to be important variables in the outcome for patients with operable breast cancer. The Cancer and Leukemia Group B study 8541 examined the effects of adjuvant treatment using conventional-range dose and dose intensity in female patients with stage II (axillary lymph node-positive) breast cancer. Methods: Within 6 weeks of surgery (radical mastectomy, modified radical mas-tectomy, or lumpectomy), 1550 patients with unilateral breast cancer were randomly assigned to one of three treat-ment arms: high-, moderate-, or low-dose intensity. The pa-tients received cyclophosphamide, doxorubicin, and 5-fluorouracil on day 1 of each chemotherapy cycle, with 5-fluorouracil administration repeated on day 8. The high-dose arm had twice the dose intensity and twice the dru