This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Majority of lung cysts occur in - \nSelect and explain. \nA. Mediastinum, B. Near carina, C. Base of the lung, D. Peribronchial tissue', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The bronchogenic cyst is a congenital lung lesion which arises from the anomalous development of foregut or tracheobronchial tree.\nCharacteristics of Bronchogenic Cysts -\n\nMost of the Bronchogenic cysts arise in the mediastinum but ~15% occur in pulmonary parenchyma.\nIn the mediastinum, they are usually located just posterior to the carnia or main stem bronchi.\nMediastinal bronchogenic cysts do not communicate with the bronchi but those situated within the lung may communicate with the airways and consequently are prone to abscess formation.\nWhen located in the lung, they are more common in right lung and lower lobes\nThese are lined by cuboidal or ciliated columnar epithelium and are usually filled with mucoid material.\n\nComplication: -\n\nInfection of the cyst leads to abscess\nCompression can produce either hyper infection of the lung or atelectasis due to obstruction\nTension pneumothorax → d/t Rupture of the cyst that communicates with bronchus.', 'role': 'assistant'}]