RATIONALE: Drugs used in chemotherapy, such as cisplatin, etoposide, and cyclophosphamide, work in different ways to stop tumor cells from dividing so they stop growing or die. Combining more than one chemotherapy drug may kill more tumor cells.

PURPOSE: This phase II trial is studying how well giving cisplatin, etoposide, and cyclophosphamide together works in treating patients with extensive-stage small cell lung cancer.

OBJECTIVES:

Primary

• Determine the safety of cisplatin, etoposide, and cyclophosphamide in patients with extensive stage small cell lung cancer.
• Determine the effect of this regimen on circulating endothelial cells in the peripheral blood of these patients.

Secondary

• Determine progression-free survival, tumor response rate, and overall survival in patients treated with this regimen.

OUTLINE: This is a multicenter study.

• Induction therapy: Patients receive cisplatin IV over 30 minutes-2 hours on day 1, etoposide IV over 1-2 hours on days 1-3 OR etoposide IV on day 1 and orally twice daily on days 2-3, and oral cyclophosphamide twice daily on days 8-19. Treatment repeats every 21 days for 4 courses in the absence of disease progression or unacceptable toxicity.
• Maintenance therapy: Patients receive oral cyclophosphamide twice daily in the absence of disease progression.

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

PROJECTED ACCRUAL: A total of 10 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed small cell lung cancer

  • Extensive stage disease (i.e., disease beyond the hemithorax and cannot be encompassed safely by a tolerable radiation field)

• Measurable disease

• Concurrent CNS metastases allowed provided patient remains asymptomatic

  • Radiotherapy or surgery for uncontrolled symptoms allowed before study entry

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3
• Hemoglobin ≥ 8 g/dL (transfusion allowed)

Hepatic

• ALT ≤ 2 times upper limit of normal (ULN)
• Bilirubin ≤ 2 times ULN

Renal

• Creatinine ≤ 1.5 mg/dL OR
• Creatinine clearance ≥ 60 mL/min

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No other malignancy within the past year except adequately treated basal cell or squamous cell skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior biologic therapy

Chemotherapy

• No prior chemotherapy

Endocrine therapy

• Concurrent corticosteroids for brain metastases allowed

Radiotherapy

• See Disease Characteristics
• Prior radiotherapy to any symptomatic site allowed provided the target site(s) was not previously irradiated
• No concurrent radiotherapy

Surgery

• See Disease Characteristics