Temozolomide and Radiation Therapy in Treating Patients With Brain Metastasis Secondary to Non-Small Cell Lung Cancer

Inclusion Criteria: Histologically confirmed non-small cell lung cancer (NSCLC), including the following histologies: Squamous cell carcinoma Adenocarcinoma Large cell carcinoma Bronchoalveolar carcinoma All variants of NSCLC At least 1 bidimensionally measurable brain metastasis Confirmed by MRI within the past two weeks, and computed tomography (CT) scan is not acceptable Biopsy is not required Not eligible for surgical resection or radiosurgery of brain metastasis Systemic disease not in immediate need of chemotherapy Age>=18 years ECOG Performance status of 0-1 More than 12 weeks of life expectancy Adequate hematologic, renal, and liver function as demonstrated by laboratory values performed within two weeks, inclusive, prior to administration of study drug or registration Absolute neutrophil count ≥ 1,500/mm^3 Platelet count ≥ 100,000/mm^3 Hemoglobin ≥ 10 g/dL Bilirubin ≤ 2 times upper limit of normal (ULN) Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) ≤ 2 times upper limit of normal (5 times ULN if liver metastases are present) Alkaline phosphatase ≤ 2 times ULN (5 times ULN if liver metastases are present) Creatinine ≤ 1.6 mg/dL Fertile patients must use effective contraception Prior biologic therapy allowed More than 4 weeks since prior chemotherapy Prior radiotherapy for local control or palliative therapy for painful bony lesions allowed Prior surgery for brain metastasis allowed At least 4 weeks since prior radiotherapy to ≥ 15% of bone marrow (2 weeks for < 15% of bone marrow) and recovered No prior radiotherapy to ≥ 50% of bone marrow Concurrent radiotherapy to painful bony lesions allowed provided no more than 15% of bone marrow is irradiated Exclusion Criteria: HIV positive AIDS-related illness Poor medical risks due to active nonmalignant systemic disease Frequent vomiting There is medical condition that would interfere with oral medication intake (e.g., partial bowel obstruction) Pregnant or nursing Prior temozolomide Prior radiotherapy to the brain, including stereotactic radiosurgery to a different lesion Concurrent intensity modulated radiotherapy or 3-D cranial radiotherapy Other concurrent investigational agents Other concurrent treatment for brain metastasis Other concurrent chemotherapy during study radiotherapy Concurrent growth factors to induce elevations in blood counts for the purposes of administration of study drug at scheduled dosing interval or to allow treatment with study drug at a higher dose