Long term follow-up of women treated with 16-week, dose-intensive adjuvant chemotherapy for high risk breast carcinoma

BACKGROUND. A Phase II study was performed evaluating the disease free and overall survival rates associated with a dose-intensive, 16-week, doxorubicin-based adjuvant chemotherapy regimen in women with breast carcinoma and → 10 involved axillary lymph nodes. METHODS. Eligible patients underwent staging with computed tomography and bone scanning and were treated with a 16-week, dose-intensive chemotherapy regimen, comprised of 8 2-week courses of cyclophosphamide, 100 mg/m² orally, on Days 1-7; doxorubicin, 40 mg/m² intravenously (i.v.), on Day 1; methotrexate, 100 mg/m² i.v., on Day 1 with leucovorin rescue, 10 mg/m², every 6 hours for 6 doses orally on Day 2; vincristine, 1 mg i.v. on Day 1; 5-fluorouracil (5-FU), 600 mg/m² i.v., on Day 2 over 2 hours; and 5-FU, 300 mg/m²/day continuous i.v. on Days 8 and 9. Tamoxifen, 20 mg daily, was administered to patients with estrogen receptor positive tumors treated after October 1988. All patients were offered locoregional radiation therapy. RESULTS. Sixty-four women were treated on protocol. The median follow-up of 27 surviving patients was > 8 years at last follow-up. Three patients were lost to follow-up. The median time to progression was 54 months, the Kaplan-Meier estimate of event free survival at 5 years was 44% (95% confidence interval [CI], 31-56%) and the Kaplan-Meier estimate of overall survival at 5 years was 57% (95% CI, 44- 69%). At 98 months the Kaplan-Meier estimate of freedom from recurrence was 31% (95% CI, 19-43%) and the Kaplan-Meier estimate of survival at 111 months was 36% (95% GI, 23-49%]. CONCLUSIONS. Despite the use of dose-intensive, doxorubicin-based, adjuvant chemotherapy, and intensive staging prior to study entry, the results of the current study are similar to those of previous reports for standard dose chemotherapy and appear inferior to those reported for high dose therapy.