Four Versus Six Cycles of Cyclophosphamide/Doxorubicin or Paclitaxel in Adjuvant Breast Cancer

PRIMARY OBJECTIVES: I. To determine the equivalence of paclitaxel given every two weeks with cyclophosphamide and doxorubicin hydrochloride (CA) given every two weeks as adjuvant therapy for women with 0-3 positive axillary lymph nodes, for disease-free survival. II. To determine if longer therapy, 12 weeks, is superior to shorter therapy, 8 weeks, of either CA or paclitaxel for disease-free survival for women with primary breast cancer with 0-3 positive axillary lymph nodes. SECONDARY OBJECTIVES: I. To determine the equivalence of paclitaxel given every two weeks with CA given every two weeks, and the potential superiority of longer vs. shorter therapy, in relation to overall survival, local control (regardless of metastatic status) and time to distant metastases (regardless of local recurrence status). II. To compare toxicities of short and long course CA and paclitaxel as adjuvant therapy for women with 0-3 positive axillary lymph node breast cancer. III. To determine the effect of long and short course CA and paclitaxel on the induction of menopause for pre-menopausal patients. IV. To assess the discrepancy of myelosuppression among the common multidrug resistance protein 1 (MDR1) haplotypes in the CA treatment arm. V. To assess the effect of MDR1 haplotypes on disease-free survival (DFS) adjusted for treatment. VI. Exploratory analysis of the effect of cytochrome P450, family 3, subfamily A, polypeptide 5 (CYP3A5), cytochrome P450, family 2, subfamily C, polypeptide 8 (CYP2C8), and cytochrome P450, family 2, subfamily B, polypeptide 6 (CYP2B6) polymorphisms on DFS and toxicity. VII. To identify genetic markers associated with the risk of developing neutropenia in adriamycin/ cyclophosphamide-treated breast cancer patients. VIII. To identify genetic markers associated with the risk of developing peripheral neuropathy in paclitaxel-treated breast cancer patients. IX. To identify genetic markers associated with differences in the efficacy of each chemotherapy regimen. X. To examine genetic associations with other response and toxicity phenotypes that become apparent during future analysis of Cancer and Leukemia Group B (CALGB) 40101 data. XI. To identify copy number variants associated with adriamycin/cyclophosphamide-induced neutropenia and paclitaxel-induced peripheral neuropathy. OUTLINE: Patients are randomized to 1 of 4 treatment arms. ARM I: Patients receive cyclophosphamide intravenously (IV) and doxorubicin hydrochloride IV on day 1. Treatment repeats every 14 days for 4 courses in the absence of disease progression or unacceptable toxicity. ARM II: Patients receive cyclophosphamide IV and doxorubicin hydrochloride IV on day 1. Treatment repeats every 14 days for 6 courses in the absence of disease progression or unacceptable toxicity. ARM III: Patients receive paclitaxel IV over 3 hours on day 1. Treatment repeats every 14 days for 4 courses in the absence of disease progression or unacceptable toxicity. ARM IV: Patients receive paclitaxel IV over 3 hours on day 1. Treatment repeats every 14 days for 6 courses in the absence of disease progression or unacceptable toxicity. Note: Randomization to Arms II and IV is no longer available, effective 12/15/2007. After completion of study treatment patients are followed up for 4-6 weeks, every 6 months for 2 years, and then annually for up to 13 years.