DISEASE CHARACTERISTICS: Histologically or cytologically confirmed non-small cell lung cancer Stage IV disease OR Recurrent unresectable disease No other conventional curative or significant palliative therapies available Measurable disease At least one lesion a minimum of one dimension in diameter of at least 20 mm No symptomatic and/or untreated CNS metastases

PATIENT CHARACTERISTICS: Age: 65 and over Performance status: ECOG 0-2 Life expectancy: At least 12 weeks Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: AST no greater than 3 times upper limit of normal Renal: Creatinine clearance at least 40 mL/min Other: No uncontrolled infection No uncontrolled seizure disorder No uncontrolled diabetes mellitus No other malignancies within the past 3 years except adequately treated basal or squamous cell skin cancer or noninvasive carcinomas

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior biologic or immunotherapy for recurrent or metastatic disease No concurrent biologic therapy

Chemotherapy: No prior chemotherapy for recurrent or metastatic disease except as radiosensitizer No other concurrent chemotherapy Endocrine therapy:

Not specified Radiotherapy: No prior radiotherapy for recurrent or metastatic disease except as adjuvant therapy At least 4 weeks since prior radiotherapy to greater than 25% of bone marrow No concurrent radiotherapy except for CNS therapy Surgery: See Disease Characteristics At least 3 weeks since prior major surgery