Letrozole Before Surgery in Treating Post-Menopausal Patients With Stage I-III Hormone-Sensitive Breast Cancer That Can Be Removed By Surgery

Inclusion Criteria

• Patients must provide informed written consent
• Eastern Cooperative Oncology Group (ECOG) performance status 0-1
• Clinical stage operable I, II or III invasive mammary carcinoma, which is estrogen receptor (ER)-positive by immunohistochemistry (IHC) and human epidermal growth factor receptor 2 (Her2)-negative by Hercep test (0 or 1+) or not overexpressed by fluorescent in situ hybridization (FISH)
• Patients who have measurable residual tumor at the primary site
• Patients who will undergo surgical treatment with either segmental resection or total mastectomy with lymph node evaluation
• Measurable disease: a mass that can be reproducibly measured by physical examination and/or ultrasound and is at least 1 cm in size
• Consultations: all patients should be evaluated by a surgeon prior to study entry
• Available core biopsies from the time of diagnosis; these may include sections paraffin-embedded material
• Post-menopausal subjects as defined by any of the following: * Subjects at least 55 years of age * Subjects under 55 years of age and amenorrheic for at least 12 months or follicle-stimulating hormone (FSH) values >= 40 IU/L and estradiol levels =< 20 IU/L * Prior bilateral oophorectomy or prior radiation castration with amenorrhea for at least 6 months
• No prior chemotherapy for this primary breast cancer
• Patients with a prior history of contralateral breast cancer are eligible if they have no evidence of recurrence of their initial primary breast cancer
• Women may have been taking tamoxifen or raloxifene as a preventive agent prior to study entry but must have discontinued the drug for at least 21 days prior to study enrollment
• Subjects must have ended hormone replacement therapy (HRT) (e.g., conjugated estrogens tablets, USP, [Premarin]), at least 1 month (30 days) prior to receiving the first dose of randomized therapy
• Creatinine =< 1.5 x upper limits of normal
• Bilirubin =< 1.5 x upper limits of normal
• Serum glutamic oxaloacetic transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) =< 1.5 x upper limits of normal
• Able to swallow and retain oral medication

Exclusion Criteria

• Patients with locally advanced disease who are candidates for other preoperative chemotherapy at the time of initial evaluation; this may include patients with locally advanced disease such as: * Inflammatory breast cancer (T4d) * Fixed axillary lymph node metastases (N2) * Metastasis to ipsilateral internal mammary node (N3)
• Locally recurrent breast cancer
• Evidence of distant metastatic disease (i.e. lung, liver, bone, brain, etc.)
• Serious medical illness that in the judgment of the treating physician places the patient at high risk of operative mortality
• Severe uncontrolled malabsorption condition or disease (i.e. grade II/III diarrhea, severe malnutrition, short gut syndrome)
• History of other malignancy; subjects who have been disease-free for 5 years, or subjects with a history of completely resected non-melanoma skin cancer or successfully treated in situ carcinomas are eligible
• Dementia, altered mental status, or any psychiatric condition that would prohibit the understanding or rendering of informed consent
• Concurrent anti-cancer therapy (chemotherapy, radiotherapy, immunotherapy, hormonal therapy, or any other biologic therapy)
• Concurrent treatment with an investigational agent
• Use of an investigational drug within 30 days or 5 half-lives, whichever is longer, preceding the first dose of study drug