Radiation Therapy Combined With Either Gefitinib or Temozolomide in Pats With NSCLC and Brain Metastases

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed non-small cell lung cancer AND newly diagnosed brain metastases meeting 1 of the following criteria: Multiple brain metastases Single brain metastasis not amenable to potentially curative treatment No advanced extracranial disease severely compromising vital functions and performance PATIENT CHARACTERISTICS: Age 18 and over Performance status WHO 0-2 Life expectancy Not specified Hematopoietic Hemoglobin > 10 g/dL Absolute neutrophil count > 1,500/mm^3 Platelet count > 100,000/mm^3 Hepatic Bilirubin ≤ 1.5 times upper limit of normal (ULN) AST and ALT ≤ 2.5 times ULN Alkaline phosphatase ≤ 2.5 times ULN (5 times ULN in the presence of documented bone metastases) No unstable or uncompensated hepatic disease that would preclude study participation Renal Creatinine clearance ≥ 40 mL/min No unstable or uncompensated renal disease that would preclude study participation Cardiovascular No myocardial infarction within the past 3 months No unstable or uncompensated cardiac disease that would preclude study participation Pulmonary No clinically active interstitial lung disease Patients with chronic stable radiographic changes who are asymptomatic eligible No other unstable or uncompensated respiratory disease that would preclude study participation Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for 12 months after completion of study treatment No nausea, vomiting, inability to swallow whole tablets/capsules, or malabsorption syndrome that would preclude oral medication ingestion or absorption No psychiatric disorder that would preclude giving informed consent or study compliance No active infection No uncontrolled diabetes mellitus No other medical condition that would preclude study participation PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No prior temozolomide Endocrine therapy Concurrent corticosteroids allowed provided dose has been stable or decreasing for ≥ 4 days before study entry Radiotherapy No prior brain irradiation Surgery Not specified Other No prior gefitinib or erlotinib More than 30 days since prior investigational clinical trial participation No other concurrent experimental drugs No other concurrent anticancer therapy No concurrent treatment with any of the following: Phenytoin Carbamazepine Rifampin Barbiturates Hypericum perforatum (St. John's wort) Other enzyme-inducing anti-epileptic drugs or tuberculostatic treatments Any drug that contraindicates administration with study drugs