Calcification as a sign of sarcomatous degeneration of malignant pleural mesotheliomas: a new CT finding.

We present two cases demonstrating, on CT examination, heavily calcified mass lesions associated with malignant pleural mesothelioma in workers occupationally exposed to asbestos. These masses proved to be osteogenic sarcomatous degeneration within mesotheliomas. The observation of dense calcification within a pleural mass should raise a suspicion of osteosarcomatous degeneration if it is seen in conjunction with other classic signs of malignant pleural mesothelioma.