Question: A patient reporting chest and cervicobrachial pain. Physical examination reveals miosis and unilateral enophthalmos. Chest X-ray shows opacity at the apex and erosion of the first ribs. What is your diagnosis? 
 Options:  <1> Pancoast tumor. <2> Mediastinal tumor. <3> Localized pleural mesothelioma. <4> Bronchioloalveolar tumor. <5> Small cell lung cancer with brain metastases.
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