PATIENT CHARACTERISTICS: Age: Over 18 Performance status: Karnofsky 70-100% Life expectancy: More than 8 weeks Hematopoietic: Not specified Hepatic: Not specified Renal: Not specified Pulmonary: No severe pulmonary disease (e.g., emphysema with carbon dioxide retention) No untreated pneumothorax Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception No other malignancy within the past 5 years except epithelial skin cancer No psychological, familial, sociological, or geographical conditions that would preclude study No intractable seizure disorder