<prompt> Which of the following statements about Branchial cysts is true:50-70 are seen in lungsMost common site is mediastinumThey are premalignant lesionsInfection is uncommon in Pulmonary bronchogenic cysts  <response>: Most common site of bronchialbronchogenic cysts is mediastinum. Only about 15 of bronchogenic cysts occur in the lungs pulmonary bronchial cysts. Pulmonary bronchogenic cysts often become infected. Bronchogenic cysts are benign lesion and do not have malignant potential not premalignant. Bronchial CystBronchogenic cysts: Review Bronchial cysts represent islands of bronchial tissue left behind during the branching of the airways during early fetal development. They arise due to abnormal budding of the tracheobronchial tree and foregut and are lined by bronchial epithelium. The most common site of bronchial cysts is mediastinum. The other site of bronchial cyst is within the pulmonary parenchyma lung Less common site - 15 Ref : Bailey and love surgery text book 27th Ed 