Isolated mediastinal mass in primary amyloidosis.

A previously healthy man with lytic bone lesion of the left talus was found to have a large middle mediastinal mass on routine admission chest roentgenogram. A large amyloid tumor of the mediastinum, representing the sole intrathoracic manifestation of primary amyloidosis, was resected. This presentation of intrathoracic amyloidosis has not previously been reported.