CT scan thymoma with atypical elements

The patient is a 56-year-old patient who presented with an abnormal chest radiograph. The CT scan through the chest is projected in transverse plane (A) showing a mass with a calcification, magnified and highlighted in B (arrow). Image C shows regions of low density in the mass (double arrows) corresponding to lack of metabolic activity in D (double arrows) and likely reflecting necrosis. Pathology revealed type C thymoma of the WHO classification with multifocal invasion through the capsule and into the pericapsular adipose lung parenchyma and pericardium.