Chemotherapy Combined With Radiation Therapy in Treating Patients With Limited-Stage Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed small cell lung cancer by one of two methods: * Fine needle aspiration biopsy * Two positive sputa * Must have limited disease as defined by all of the following: * Stage I-IIIB * Confined to 1 hemithorax * No T4 tumor based on malignant pleural or pericardial effusion * Patients with pleural effusion too small to tap under CT guidance and not evident on chest x-ray are allowed * No N3 disease based on contralateral hilar or contralateral supraclavicular involvement * Measurable or evaluable disease * Tumor must be able to be encompassed by specified radiotherapy fields without unacceptable risk of serious pulmonary compromise * No complete tumor resection * No pericardial effusion (regardless of cytology) PATIENT CHARACTERISTICS: Age * 18 and over Performance status * Zubrod 0-1 Life expectancy * Not specified Hematopoietic * Absolute granulocyte count at least 1,500/mm\^3 * Platelet count at least 120,000/mm\^3 Hepatic * Bilirubin no greater than 1.5 mg/dL * No known Gilbert's disease Renal * Creatinine no greater than 1.5 mg/dL Cardiovascular * No myocardial infarction within the past 6 months * No symptomatic heart disease Pulmonary * Forced expiratory volume (FEV)\_1 at least 1.0 L/sec * No uncontrolled bronchospasms * No uncompensated chronic obstructive pulmonary disease Other * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No pre-existing peripheral neuropathy grade 2 or greater * No other malignancy within the past 2 years except curatively treated basal or squamous cell skin cancer or carcinoma in situ of the bladder or cervix * No other concurrent serious medical illness PRIOR CONCURRENT THERAPY: Biologic therapy * No prior biologic therapy Chemotherapy * No prior chemotherapy Endocrine therapy * Not specified Radiotherapy * No prior radiotherapy * No concurrent intensity-modulated radiotherapy Surgery * See Disease Characteristics Other * At least 7 days since prior enzyme-inducing anti-convulsant drugs (EIACDs) (e.g., phenytoin, carbamazepine, or phenobarbital) if used on a regular basis for more than 2 weeks * Less than 2 weeks of regular use of EIACDs does not require a 7-day wash-out period * At least 14 days since prior Hypericum perforatum (St. John's wort) * No concurrent EIACDs * No concurrent amifostine during chemoradiotherapy * Concurrent gabapentin or other non-EIACDs allowed