DISEASE CHARACTERISTICS:

• Histologically or cytologically proven invasive adenocarcinoma of the breast

  • Stage IIA, IIB, or IIIA
  • Confined to the breast and ipsilateral axilla (cN0-1) on clinical examination
  • At least 1 histologically positive axillary node
  • No lymph nodes clinically fixed to each other or to other structures (cN2)

  • HER2 strongly positive (3+ by immunostain OR gene amplification by fluorescent in situ hybridization)

    • Submission of tumor block required

• Must have undergone axillary dissection and either total mastectomy OR lumpectomy

  • Sentinel node dissection allowed, if followed by axillary dissection
  • No diffuse tumors by mammography in patients treated with lumpectomy
  • No more than 84 days since prior surgery for breast cancer (e.g., lumpectomy, mastectomy, axillary dissection, or re-excision of lumpectomy margins)
• No bilateral malignancy, contralateral mass, or mammographic abnormality unless histologically proven as benign
• No suspicious palpable nodes in the contralateral axilla or palpable supraclavicular or infraclavicular nodes unless histologically proven not to be involved with tumor
• No primary T4 tumors (for any reason)

• No prior breast cancer, including ductal carcinoma in situ

  • Prior lobular carcinoma in situ allowed
• Bone pain allowed provided there is no metastatic disease by x-ray, MRI, or biopsy

• Hormone receptor status:

  • Estrogen and progesterone status known

PATIENT CHARACTERISTICS:

Age:

• Not specified

Sex:

• Female

Menopausal status:

• Not specified

Performance status:

• Not specified

Life expectancy:

• At least 10 years, excluding diagnosis of breast cancer

Hematopoietic:

• Platelet count at least 100,000/mm^3*
• Absolute neutrophil count at least 1,500/mm^3 (unless determined by the investigator to be normal for ethnic or racial variation) NOTE: *Significant underlying hematologic disorders must be excluded if above upper limit of normal (ULN)

Hepatic:

• Bilirubin no greater than ULN
• SGOT less than 1.5 times ULN
• Alkaline phosphatase less than 2.5 times ULN
• No systemic hepatic disease that would preclude study participation

Renal:

• Creatinine normal
• No systemic renal disease that would preclude study participation

Cardiovascular:

• LVEF at least lower limit of normal by MUGA
• No cardiovascular disease that would preclude study participation
• No angina pectoris requiring treatment
• No cardiomegaly on chest x-ray
• No prior myocardial infarction by clinical diagnosis or by EKG or other test
• No prior congestive heart failure
• No prior cardiomyopathy
• No cardiac arrhythmia requiring medication
• No severe conduction abnormality
• No clinically significant valvular disease
• No poorly controlled hypertension (diastolic greater than 100 mm Hg), unless adequately controlled by medication
• No ventricular hypertrophy on EKG

Other:

• Not pregnant or nursing
• Fertile patients must use effective barrier contraception
• No other prior malignancy within the past 5 years except effectively treated carcinoma in situ of the cervix, melanoma in situ, or basal cell or squamous cell skin cancer
• No psychiatric or addictive disorders that would preclude informed consent
• No sensory or motor neuropathy grade 2 or greater
• No contraindications to corticosteroids

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior biologic therapy for this breast cancer

Chemotherapy:

• No prior chemotherapy for this breast cancer
• No prior anthracycline or taxane therapy for any cancer

Endocrine therapy:

• No prior hormonal therapy for this breast cancer
• No concurrent hormonal therapy (e.g., birth control pills or ovarian hormone replacement therapy)
• No concurrent raloxifene or other selective estrogen-receptor modulators

Radiotherapy:

• No prior radiotherapy for this breast cancer
• No concurrent radiotherapy to internal mammary nodes
• No other concurrent radiotherapy except as specified in study

Surgery:

• See Disease Characteristics

Other:

• No other concurrent investigational agents