A Phase II And Biologic Correlative Study Investigating ARIMIDEX In Combination With IRESSA (ZD1839) In Post-Menopausal Patients With Estrogen Receptor-Positive Metastatic Breast Carcinoma Who Have Previously Failed Hormonal Therapy

Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed breast cancer

- Metastatic or locally advanced unresectable disease

- At least 1 measurable target lesion that has not been irradiated

- New lesions in a previously irradiated field allowed as sites of measurable
disease

- Progressive disease after more than 2 months of aromatase inhibitor therapy

- No known CNS disease or unevaluated CNS symptoms suggestive of brain metastases

- Hormone receptor status:

- Estrogen receptor or progesterone receptor positive

PATIENT CHARACTERISTICS:

Age

- 18 and over

Sex

- Female

Menopausal status

- Post-menopausal by 1 of the following criteria:

- Age 50 and over and has not menstruated during the past year or has castrate
follicle-stimulating hormone (FSH) levels (greater than 40 IU/L)

- Under age 50 and has castrate FSH levels

- Received prior bilateral oophorectomy and has castrate FSH levels

Performance status

- ECOG 0-2

Life expectancy

- At least 12 weeks

Hematopoietic

- Absolute neutrophil count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

Hepatic

- Bilirubin no greater than 1.5 times upper limit of normal (ULN)

- ALT or AST no greater than 2.5 times ULN (5 times ULN if liver metastases present)

Renal

- Creatinine no greater than 1.5 times ULN

Cardiovascular

- No history of congestive heart failure requiring therapy

- No ventricular arrhythmia requiring therapy

- No unstable angina pectoris

- No myocardial infarction within the past 6 months

Other

- Able to swallow oral medication

- No other malignancy within the past 5 years except nonmelanoma skin cancer or
carcinoma in situ of the cervix

- No known malabsorption condition or other condition that would impair absorption of
study drug

- No active infection

- No other concurrent medical condition that would preclude study

- No known severe hypersensitivity to ZD 1839 or any excipients

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- No prior chemotherapy except in adjuvant setting

- No concurrent chemotherapy for breast cancer

Endocrine therapy

- See Disease Characteristics

- More than 30 days since other prior hormonal therapy (including hormone replacement
therapy and megestrol)

- Concurrent steroids for other reasons besides skin toxicity allowed

- No other concurrent hormonal therapy (including megestrol) for breast cancer

Radiotherapy

- See Disease Characteristics

Surgery

- Recovered from prior oncologic or other major surgery

- No concurrent ophthalmic surgery

Other

- More than 30 days since prior anticancer therapy

- More than 30 days since prior non-approved or investigational drugs

- No prior epidermal growth factor receptor or HER2 blockers

- No concurrent phenytoin, carbamazepine, barbiturates, rifampicin, phenobarbital,
Hypericum perforatum, or systemic retinoids

- No other concurrent investigational therapy for breast cancer

- Concurrent bisphosphonates for metastatic bone disease allowed