The following is not the differential diagnosis of an anterior mediastinal mass –

Anterior mediastinal masses:- Thymoma, Lymphoma, teratoma, Aneurysm of ascending aorta, pericardial cyst, retrosternal thyroid, Morgagni hernia. Middle mediastinal masses:- Lymph node enlargement, bronchogenic cyst, pericardial cyst, Aortic arch aneurysm, coronary / pulmonary aneurysm, azygous vein enlargement. Tortuous innominate artery(Kant.-II) Posterior mediastinal masses:- Neurogenic tumor (neuroblastoma, schwannoma, neurofibroma), Aneurysm of descending aorta, lymph node enlargement, neuroenteric cyst, anterior meningocele, bochdolek hernia.