Intra-thoracic goiters occur in all mediastinal compartments (in one series, 25% of intrathoracic goiters occurred in posterior mediastinum/as many as 10% of mediastinal masses may be intrathoracic goiters)
Diagnosis
CXR/Chest CT Patterns
Cervicothoracic sign: absence of superior border (because mass is in contact with soft tisuses of neck, not air)
I131 scan: diagnostic
I125 is not adequate due to its weaker energy is absorbed by bone