S0119: Combination Chemotherapy in Treating Patients With Extensive-Stage Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed extensive stage small cell lung cancer (SCLC) * Malignant pleural effusion constitutes extensive stage disease * Must have disease outside area of prior surgical resection or a new lesion must be present * Controlled brain metastases allowed (asymptomatic and previously treated with surgery and/or radiotherapy) * Brain metastases must be re-evaluated by CT scan or MRI after completion of radiotherapy or surgery PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * Zubrod 0-2 Life expectancy: * Not specified Hematopoietic: * Absolute granulocyte count at least 1,500/mm\^3 * WBC at least 3,000/mm\^3 * Platelet count at least 100,000/mm\^3 Hepatic: * Bilirubin no greater than 1.25 times upper limit of normal (ULN) * SGOT or SGPT no greater than 2.5 times ULN Renal: * Not specified Other: * Not pregnant or nursing * Fertile patients must use effective contraception * No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or other adequately treated stage I or II cancer in complete remission PRIOR CONCURRENT THERAPY: Biologic therapy: * No prior biologic therapy for SCLC Chemotherapy: * No prior systemic chemotherapy for SCLC Endocrine therapy: * Not specified Radiotherapy: * See Disease Characteristics * No prior radiotherapy for SCLC except for brain metastases Surgery: * See Disease Characteristics * At least 2 weeks since prior surgery (thoracic or other major surgery) and recovered