Description of Specimen
The specimen consists presumably of one lobe of the thymus; it has been replaced by tumour. The
tumour has a thick capsule; the cut surface shows a nodular pattern with nodules delineated by
rather pale collagenous tissue. In some areas the tumour is apparently solid, in others there are
cysts which in some cases are small enough to give a lacey pattern to the tumour. There are areas
of haemorrhage apparent as well. It is not known whether this lesion was associated with
myasthenia gravis or not. The histology is that of a mixed tumour but it is predominantly epithelial
in type.