Inclusion Criteria

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 greater than 40%

- No unstable angina

- No recent deep venous thrombosis requiring anticoagulation

Pulmonary:

- FEV1 and DLCO greater than 30% of predicted

- pCO_2 less than 50 mm Hg

- pO_2 greater than 60 mm Hg on room air

- No recent pulmonary embolism requiring anticoagulation

Other:

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No active infection

- HIV negative

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- At least 30 days since prior biologic therapy for the malignant tumor

Chemotherapy:

- No prior decitabine

- At least 30 days since other prior chemotherapy for the malignant tumor

Endocrine therapy:

- See Disease Characteristics

Radiotherapy:

- See Disease Characteristics

- At least 30 days since prior radiotherapy for the malignant tumor (14 days for
localized radiotherapy to nontarget lesions) and recovered

Surgery:

- See Disease Characteristics