RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Combining chemotherapy with peripheral stem cell transplantation may allow the doctor to give higher doses of chemotherapy drugs and kill more tumor cells. Interleukin-2 and colony-stimulating factors such as sargramostim may help a person's immune system kill more tumor cells.

PURPOSE: Phase II trial to study the effectiveness of combination chemotherapy and peripheral stem cell transplantation followed by interleukin-2 and sargramostim in treating patients who have inflammatory stage IIIB or metastatic stage IV breast cancer.

OBJECTIVES:

• Determine the event-free survival of patients treated with high-dose chemotherapy with busulfan, melphalan, and thiotepa plus peripheral blood stem cell (PBSC) support followed by low dose immunotherapy with interleukin-2 (IL-2) and sargramostim (GM-CSF) for inflammatory stage IIIB and responsive stage IV breast cancer.
• Determine the toxic effects of this therapy in these patients.

OUTLINE: Peripheral blood stem cells (PBSC) are collected from the patient following stimulation with cyclophosphamide/paclitaxel/filgrastim (G-CSF) according to FHCRC 506 protocol or an approved FHCRC cytokine mobilization study. Patients must receive 1 course of cyclophosphamide and paclitaxel if cytokines alone are used to mobilize cells (FHCRC-506.03 protocol). G-CSF alone will be used to collect syngeneic PBSC (FHCRC-753).

Patients receive oral busulfan every 6 hours on days -8, -7, and -6. Melphalan IV is given on days -5 and -4 beginning at least 12 hours after busulfan. Thiotepa IV is given on days -3 and -2 followed by PBSC infusion on day 0 beginning 36-48 hours after the last dose of thiotepa.

All patients receive oral tamoxifen daily after transplant for 5 years or until relapse. Eligible patients receive interleukin-2 (IL-2) subcutaneously (SQ) daily plus sargramostim (GM-CSF) SQ on Monday, Wednesday, and Friday for 12 weeks beginning 30-100 days after transplantation. Patients with negative estrogen and progesterone status may discontinue tamoxifen therapy following IL-2/GM-CSF treatment. Patients receive radiotherapy after IL-2/GM-CSF treatment if no prior radiotherapy was given before transplantation.

Patients are followed every 3 months for 2 years, then every 6 months thereafter.

PROJECTED ACCRUAL: Approximately 70 patients will be accrued for this study over 2 years.

• Biological: aldesleukin
• Biological: sargramostim
• Drug: busulfan
• Drug: melphalan
• Drug: tamoxifen citrate
• Drug: thiotepa
• Procedure: bone marrow ablation with stem cell support
• Procedure: peripheral blood stem cell transplantation
• Radiation: radiation therapy

DISEASE CHARACTERISTICS:

• Stage IIIB inflammatory breast cancer

  • Received 4-7 courses of doxorubicin or taxane based regimen

• Responsive stage IV breast cancer metastatic to soft tissue and/or bone

  • Partial or complete response after initial chemotherapy for metastatic disease
  • Received 4-7 courses of doxorubicin or taxane based regimen OR
  • Locally recurrent disease rendered disease free after surgery or radiotherapy
  • Bone disease responsive if demonstrated sclerosis of prior lesions with no new lesions
• Received 1 course of cyclophosphamide 4 g/m^2 and paclitaxel 250 mg/m^2 on protocol FHCRC-506.03
• Stem cell collection after mobilization with cyclophosphamide/paclitaxel or after an FHCRC approved cytokine protocol
• Syngeneic stem cells collected by using filgrastim (G-CSF) according to protocol FHCRC-753
• Adequate number of peripheral blood stem cells stored (at least 2,500,000 CD34+ cells)
• No CNS lesion (brain or carcinoid meningitis)

• Hormone receptor status:

  • Any status

PATIENT CHARACTERISTICS:

Age:

• 18 to 65

Menopausal status:

• Not specified

Performance status:

• Karnofsky 70-100%

Life expectancy:

• Not specified

Hematopoietic:

• Not specified

Hepatic:

• Bilirubin no greater than 2 mg/dL
• SGOT or SGPT no greater than 2.5 times normal

Renal:

• Creatinine no greater than 2 mg/dL OR
• Creatinine clearance at least 50 mg/min

Cardiovascular:

• LVEF greater than 50%
• LVEF must be performed for symptoms of congestive heart failure, abnormal cardiac exam, or history of doxorubicin total dose greater than 400 mg/m^2

Pulmonary:

• No clinically significant pulmonary disease (diffusion capacity corrected less than 60% of predicted)

Other:

• Not pregnant
• HIV negative
• No history of seizures
• No hypersensitivity to E. coli preparations
• No active autoimmune disease
• No significant active infection precluding transplantation

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior transplantation

Chemotherapy:

• See Disease Characteristics
• No more than 1 prior chemotherapy regimen for stage IV disease

Endocrine therapy:

• Not specified

Radiotherapy:

• Not specified

Surgery:

• Not specified