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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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The commonest anterior mediastinal tumour is
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The correct answer 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.