The commonest anterior mediastinal tumour is
Thymomas are the most common anterosuperior mediastinal tumors accounting for 25% of the total.They are commonly associated with myasthenia gravis.Diagnosis and treatment is best achieved by complete thymectomy. Reference:SRB's manual of surgery,5th edition,page no:1127.
Aneurysm of descending aoa
Neurogenic tumour
Thymoma
Bronchogenic cyst
Cardio thoracic surgery  