A 36 year old man presented with chest symptoms had a radiological lef
t upper mediastinal lesion, that was interpreted as an anterior medias
tinal tumour, consistent with a thymoma. At operation an inflammatory
pseudotumour was found in the left upper lobe of the lung, that was pr
ojecting across and in front of the mediastinum. The investigation and
surgical management of these rumours are reviewed in the light of the
presenting symptoms and radiological imaging. (C) 1997 Elsevier Scien
ce B.V.