OBJECTIVES: Primary * Determine the clinical response rate in postmenopausal women with locally advanced hormone receptor-positive breast cancer treated with neoadjuvant and adjuvant exemestane. Secondary * Determine the response rate by mammography, ultrasound, MRI, and positron emission tomography scan in patients treated with this drug. * Determine the time to progression in patients treated with this drug. * Compare the expression of hormone receptors and epidermal growth factor receptors (including HER2/neu) in patients prior to and after treatment with this drug and correlate these results with clinical response rates. OUTLINE: Patients receive oral exemestane once daily for 16 weeks in the absence of disease progression or unacceptable toxicity. After 16 weeks, patients undergo surgery and then continue exemestane once daily for a total of 5 years (including the 16 weeks before surgery). Patients are followed every 3 months for 2 years after surgery and then every 6 months thereafter. PROJECTED ACCRUAL: A total of 16-46 patients will be accrued for this study within 2 years.
DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed breast cancer * Locally advanced disease (stage II or III) * Not amenable to breast-conserving therapy at the time of diagnosis * Measurable disease meeting 1 of the following criteria: * Bidimensionally measurable palpable lesion at least 1 cm by caliper * Unidimensionally measurable lesion at least 1 cm by a positive mammogram, ultrasound, or MRI * No evidence of disease outside the breast or chest wall except ipsilateral axillary lymph nodes * Hormone receptor status: * Estrogen and/or progesterone receptor positive PATIENT CHARACTERISTICS: Age * Postmenopausal Sex * Female Menopausal status * Postmenopausal, defined as any of the following: * Over 60 years of age * Over 45 years of age with an intact uterus and amenorrhea for more than 12 months * Prior hysterectomy with follicle-stimulating hormone levels within the postmenopausal range * Prior ovarian ablation (i.e., bilateral surgical) Performance status * ECOG 0-3 Life expectancy * Not specified Hematopoietic * Not specified Hepatic * Bilirubin less than 1.5 times upper limit of normal (ULN) Renal * Creatinine less than 2 mg/dL Other * No other prior or concurrent cancer except nonmetastatic nonmelanoma skin cancer, carcinoma in situ of the cervix, or cancer cured by surgery within the past 5 years PRIOR CONCURRENT THERAPY: Biologic therapy * No prior biologic therapy for breast cancer Chemotherapy * No prior chemotherapy for breast cancer Endocrine therapy * No prior hormonal therapy for breast cancer Radiotherapy * No prior radiotherapy for breast cancer Surgery * Not specified