About the Degeneration of a Mediastinal Bronchogenic Cyst

The appropriate management of asymptomatic congenital pulmonary malformations (CPMs) remains controversial. Prophylactic surgery is recommended to avoid the risk for development of pulmonary infections and to prevent the highly debated development of malignancy. However, the true risk for development of malignancy remains unknown. A systematic review analyzed all cases in which lung tumors associated with CPMs in both the pediatric and adult populations were described.

We report the case of a 37-year-old woman with a radiographically cystic lung lesion. Lobectomy was performed. Histopathologic examination showed a bronchioloalveolar carcinoma arising in a bronchogenic cyst. This suggests that epithelial cells of bronchogenic cysts can undergo malignant transformation. It may be prudent to recommend complete resection of any bronchogenic cyst.

The management of patients with uncomplicated bronchogenic cysts has evolved over the last decade with the development of more precise diagnostic techniques and a better understanding of the variable natural history of these lesions. Although an aggressive surgical approach is still indicated for infants and children, it is acceptable to treat asymptomatic bronchogenic cysts in adults in a conservative manner. Observation alone may be indicated for small, classic, asymptomatic cysts. The use of mediastinoscopy or percutaneous or transbronchial needle techniques for carinal or paratracheal cysts offers the option of fluid aspiration or wall biopsy, thus avoiding thoracotomy. An air-fluid level in the cyst, the presence of malignant cells in the aspirate or biopsy, the development of symptoms, or enlargement or recurrence of the cyst on follow-up examination mandates complete surgical removal at thoracotomy. This is also indicated for intraparenchymal bronchogenic cysts, which are more prone to bronchial communication and infectious complications and for which the distinction from a carcinoma with a cystic component may be difficult.