Decitabine in Treating Patients With Unresectable Lung or Esophageal Cancer or Malignant Mesothelioma of the Pleura

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed unresectable primary small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC), unresectable esophageal cancer, malignant pleural mesothelioma, or pleural effusions secondary to extrathoracic malignancies * Disease must be readily accessible to biopsy by endoscopy or percutaneous fine-needle aspiration * Extrathoracic metastatic disease allowed if no evidence of active intracranial or leptomeningeal metastases * Patients treated with prior resection or radiotherapy for intracranial metastatic disease may be eligible provided there is no evidence of active disease on two MRIs (taken one month apart) and patients require no anticonvulsant medications or steroids to control residual symptoms * No limited stage SCLC or operable NSCLC PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * ECOG 0-2 Life expectancy: * At least 6 months Hematopoietic: * Platelet count greater than 100,000/mm\^3 * Hemoglobin greater than 10 g/dL * WBC greater than 3,500/mm\^3 Hepatic: * PT normal * Bilirubin less than 1.5 times upper limit of normal Renal: * Creatinine no greater than 1.6 mg/dL OR * Creatinine clearance greater than 60 mL/min Cardiovascular: * Any of the following conditions require clearance by a cardiologist: * Prior coronary artery disease * Prior transmural myocardial infarction * Congestive heart failure * Fixed defects on thallium scan with ejection fraction grea…