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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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A 70 year old male presentes with breathlessness, facial swelling and dilated veins on the chest wall. The MOST common cause is:
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The correct answer is  Breathlessness, facial swelling and dilated veins on the chest wall, are features of Superior vena caval obstruction. Lung cancer, paicularly of small cell and squamous cell histologies, accounts for approximately 85% of all cases of malignant origin. In young adults, malignant lymphoma is a leading cause of SVCS. When SVCS is noted in a young man with a mediastinal mass, the differential diagnosis is lymphoma vs primary mediastinal germ cell tumor. Ref: Harrisons principles of internal medicine, 18th edition, Page: 2266