Inclusion Criteria:

1. Histologically proven primary invasive breast cancer which is thought to be suitable
for neo-adjuvant treatment

2. Pathologically proven lymph node positive tumor(FNAB or Core biopsy)

3. Tumor must be ER positive(eligible patients include Allred score 5 and more, Modified
Allred 4 and more) and HER-2 negative(IHC score is 0-1+; If IHC score is 2+, the
result of FISH or SISH is negative)

4. Premenopausal women

Premenopausal status as defined by :

- Last menses within 6 month of randomization or

- For patients who have had a hysterectomy, E2 ≥ 20PG/mL and FSH < 30mIU/Ml within
4 weeks of randomization

5. Ages of 20 to 50 years old

6. Pre-treatment haematology and biochemistry values within acceptable limits :

- ANC ≥ 1.5 × 109/l

- Hb > 9g/dl

- Platelets ≥ 100 × 109/l

- AST/ALT ≤ 1.5 × ULN(Upper Limit of Normal)

- ALP ≤ 1.5 × ULN

- Serum bilirubin ≤ 1.5 × ULN

- Serum creatinine ≤ 1.5 × ULN

7. ECOG PS of 0 or 1

8. No concomitant medical, psychiatric or geographic problems that might prevent
completion of treatment or follow-up

9. Before any study-specific procedures, the appropriate written informed consent must
be obtained

Exclusion Criteria:

1. Inflammatory breast cancer

2. Inoperable disease that is judged very unlikely to be rendered operable by
neo-adjuvant treatment

3. ER poor disease as defined locally

4. Known severe hypersensitivity to GnRHa treatment

5. Bilateral invasive breast cancer

6. Other serious illness or medical condition:

- congestive heart failure or unstable angina pectoris, previous history of
myocardial infarction within 1 year from study entry, uncontrolled hypertension
or high-risk uncontrolled arrhythmias

- history of significant neurologic or psychiatric disorders including psychotic
disorders, dementia or seizures that would prohibit the understanding and giving
of informed consent

- active uncontrolled infection

7. HRT within 4 weeks of starting treatment

8. Definite contra-indications for the use of corticosteroids.

9. Last 10 years with a history of other malignant tumor (except in the case of basal
cell carcinoma or cervical carcinoma in situ, and where treatment consisted solely of
resection)

10. Systemic metastatic (Tests for the diagnosis of systemic metastatic comply with the
guideline in each institution)

11. Pregnant or breastfeeding women

12. Chronic oral treatment with corticosteroids unless initiated > 6 months prior to
study entry and at low dose (≤ 20 mg methylprednisolone or equivalent).