A 46-year-old patient who developed a right pleural mesothelioma 18 years after asbestos exposure was found to have diffuse reticular nodular infiltrates in both lungs. Lung biopsy by fiberoptic bronchoscopy revealed alveolar and interstitial spread of the neoplastic cells. A dramatic clinical and radiologic response occurred after treatment with a combination of doxorubicin (Adriamycin) and 5-Azacytidine.