Mediastinal masses may be caused by a wide variety of neoplastic and non-neoplastic pathologies. It is helpful to identify the location of the mass since this significantly reduces the breadth of the differential diagnosis.
The mediastinum does not have strict boundaries within it and large lesions will span more than one 'compartment'. More recently 3, location has been described as:
prevascular
visceral
paraspinal
These terms correspond to anterior, middle and posterior.
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