DISEASE CHARACTERISTICS: Histologically confirmed unresectable stage II, IIIA, or IIIB non-small cell lung cancer No distant metastases No prior complete (or gross subtotal) tumor resection No post-resection intrathoracic tumor recurrence Pleural effusion seen on a chest x-ray allowed only if appearing after thoracotomy or other invasive thoracic procedure (pleural effusion acceptable if seen only on CT scan, not on chest x-ray) Must be ineligible or refused participation in protocol RTOG-9309

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 70-100% Life expectancy: Not specified Hematopoietic: Absolute granulocyte count at least 2,000/mm3 Platelet count at least 100,000/mm3 Hemoglobin at least 8.0 g/dL Hepatic: Bilirubin no greater than 1.5 mg/dL\* SGOT no greater than 1.5 times upper limit of normal\* \* Unless due to documented benign disease Renal: Creatinine no greater than 1.5 mg/dL Cardiovascular: No myocardial infarction within the past 6 months No symptomatic heart disease, including angina, congestive heart failure, or uncontrolled arrhythmias Other: No weight loss of greater than 5% in 3 months prior to diagnosis No other prior or concurrent invasive malignancy within the past 3 years except nonmelanomatous skin cancer Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior chemotherapy Endocrine therapy: Not specified Radiotherapy: No prior thoracic or neck radiotherapy Surgery: See Disease Characteristics