Preoperative Hormone Therapy for Postmenopausal Women With ER+ Clinical Stage T2-4 Tumors

This study will develop preliminary data regarding the efficacy and safety of exemestane in
the preoperative treatment of postmenopausal women with ER+ or PR+ tumors. This trial is also
designed to develop a predictive model to correlate expression of the known isoforms of ER
and progesterone receptor (PR) and the aromatase enzyme with response to estrogenic
deprivation using exemestane.

Inclusion Criteria:

- Histologically or cytologically confirmed breast cancer

- ER positive (+)

- Primary tumor 2-4 regional lymph nodes 0-2 (T2-4N0-2); patients may have metastatic
disease, provided local-regional surgery is clinically indicated

- Clinical stage II/III

- Postmenopausal- defined as having had a previous bilateral oophorectomy or, for women
with no prior hysterectomy, the absence of spontaneous menstrual cycles for more than
1 year

- Newly diagnosed

- Patients with prior non-breast malignancies are eligible if they have been disease
free for >= 5 years before study entry; patients with squamous or basal cell carcinoma
of the skin that has been effectively treated, carcinoma in situ of the cervix that
has been treated by surgery only, or lobular carcinoma in situ (LCIS) of the
ipsilateral or contralateral breast that has been treated by surgery only are
eligible, even if the cancer was diagnosed within 5 years before randomization

- Serum creatinine =< 1.5 x institutional upper limit of normal (ULN)

- Hemoglobin within normal limits for institution

- Absolute granulocyte count >= 1500

- Platelet count >= 100,000

- Serum glutamic oxaloacetic transaminase (SGOT), aspartate aminotransferase (AST) or
serum glutamate pyruvate transaminase (SGPT), alanine aminotransferase (ALT) =< 2.5 x
ULN

- Total bilirubin < 2 x ULN for institution

- Alkaline phosphatase < 2 x the ULN

Exclusion Criteria:

- Completely resected

- Prior hormone or chemotherapy

- Unable to take oral medication

- Patients who have nonmalignant systemic disease (cardiovascular, renal, hepatic, etc.)
that would preclude their being subjected to protocol therapy