Trastuzumab and Interleukin-2 in Treating Patients With Metastatic Breast Cancer

Inclusion Criteria:

Histologically or cytologically confirmed breast cancer

Primary and/or metastatic disease

HER2 overexpression 3+ by immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH)

Tumors with HER2 2+ overexpression by IHC allowed if confirmed by FISH
Progressive disease during or within 12 months of receiving prior regimen containing trastuzumab (Herceptin)

Unidimensionally measurable disease

At least 20 mm by conventional techniques OR at least 10 mm by spiral CT scan

The following are not considered measurable:

Bone metastases
Pleural or peritoneal effusion
Ascites
Leptomeningeal disease
Lymphangitic disease
Inflammatory breast cancer
Cystic lesions
CNS lesions

CNS metastases allowed if all of the following conditions are met:

Asymptomatic
At least 3 months since prior surgery and/or cranial irradiation
At least 3 weeks since prior steroids

Hormone receptor status:

Not specified
Male or female
Performance status - ECOG 0-2
Granulocyte count at least 1,000/mm^3
Platelet count at least 100,000/mm^3
Bilirubin no greater than 1.5 times upper limit of normal (ULN)
SGOT and SGPT no greater than 2 times ULN (5 times ULN for liver metastases)
Alkaline phosphatase no greater than 2 times ULN (5 times ULN for liver metastases)
Creatinine no greater than 1.5 times ULN
LVEF at least lower limit of normal by MUGA or echocardiogram
No congestive heart failure or active ischemic heart disease
Not pregnant or nursing
Negative pregnancy test
Fertile patients must use effective contraception
No psychiatric illness, medical condition, or uncontrolled infection that would preclude study
No underlying immunodeficiency (e.g., HIV or autoimmune disease)
No other prior malignancy within the past 5 years except nonmelanoma skin cancer or carcinoma in situ of the cervix
See Disease Characteristics
Prior cumulative doxorubicin dose no greater than 360 mg/m^2
At least 3 weeks since prior chemotherapy
No more than 2 prior chemotherapy regimens for metastatic disease
No concurrent chemotherapy
See Disease Characteristics
At least 3 weeks since prior endocrine therapy
No concurrent corticosteroids or dexamethasone
Concurrent hormones allowed for conditions unrelated to disease (e.g., insulin for diabetes)
See Disease Characteristics
At least 3 weeks since prior radiotherapy
No prior radiotherapy to study lesion, unless evidence of disease progression
No concurrent palliative radiotherapy
See Disease Characteristics
At least 4 weeks since prior major surgery
No concurrent immunosuppressive drugs