Inclusion Criteria:

- Histologically confirmed invasive, hormone receptor-positive (ER
and/or PR positive) breast cancer

- Stage I-III breast cancer including any primary tumor >= 1cm by ultrasound

- Diagnosis by core needle biopsy with placement of metallic clip at tumor site

- Sentinel lymph node biopsy (US-guided FNA may be substituted if palpable axillary
lymphadenopathy)

- Evaluation by a surgeon to determine eligibility for breast conservation

- Postmenopausal status (age >= 60, age < 60 and FSH and estradiol in the
postmenopausal range, prior bilateral oophorectomy)

- Serum creatinine < 1.5 x ULN or creatinine clearance > 50 mL/minute (calculated by
Cockcroft-Gault formula.)

- Serum bilirubin < 1.5 x ULN

- Serum potassium must not be less than 4mmol/L (supplementation allowed)

- Serum calcium or magnesium within normal range (supplementation allowed)

- Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) <= 2.5 x ULN or
alkaline phosphatase (ALP) <= 2.5 x ULN

- ECOG Performance Status 0,1,2

- ECG QTc < 480 msec

- Measurable disease

- Written, informed consent

Exclusion Criteria:- Inflammatory breast cancer

- Metastatic breast cancer excluding disease in regional lymph nodes

- Inoperable disease considered irreversible with neoadjuvant endocrine therapy

- HER2-overexpressed breast cancer

- Prior chemotherapy or radiotherapy for the treatment of the current breast cancer

- Prior hormonal therapy for the treatment of the current breast cancer

- Prior surgical biopsy, lumpectomy, mastectomy for the current breast cancer

- Any concurrent condition which in the Investigator's opinion makes it inappropriate
for the patient to participate in the trial or which would jeopardize compliance with
the protocol

- Currently active diarrhea that may affect the ability of the patient to absorb ZD6474
or tolerate diarrhea

- Clinically significant cardiac event such as myocardial infarction; New York Heart
Association (NYHA) classification of heart disease >2 within 3 months before entry;
or presence of cardiac disease that, in the opinion of the Investigator, increases
the risk of ventricular arrhythmia.

- History of arrhythmia (multifocal premature ventricular contractions (PVCs),
bigeminy, trigeminy, ventricular tachycardia (VT) or uncontrolled atrial
fibrillation) which is symptomatic or requires treatment (CTCAE grade 3) or
asymptomatic sustained VT. Atrial fibrillation controlled on medication is not
excluded.

- Previous history of QTc prolongation as a result of another medication that required
discontinuation of that medication.

- Congenital long QT syndrome or 1st degree relative with unexplained sudden death <40
years of age.

- Presence of left bundle branch block (LBBB).

- QTc with Bazett's correction that is unmeasurable, or >= 480 msec on screening ECG.
If a patient has QTc > = 480 msec on screening ECG, the screen ECG may be repeated
twice (at least 24 hours apart). The average QTc from the three screening ECGs must
be < 480 msec in order for the patient to be eligible for the study.

- Use of any concomitant medication that may cause QTc prolongation, induce Torsades de
Pointes or induce CYP3A4 function.

- Hypertension not controlled by medical therapy (systolic blood pressure greater than
160 mm Hg or diastolic blood pressure greater than 100 mm hg).

- Previous or current malignancies of other histologies within the last 5 years, with
the exception of cervical carcinoma in situ and adequately treated basal cell or
squamous cell carcinoma of the skin.

- Major surgery within 4 weeks or incompletely healed surgical incision before starting
study therapy.

- Receipt of any investigational agents within 30 days prior to commencing study
treatment

- Previous enrollment or randomization of treatment in the present study