Bronchogenic cysts in adults: Frequently mistaken for a solid mass on computed tomography

Background: Bronchogenic cysts are congenital malformations and are often detected in asymptomatic patients as an incidental finding. Growth can cause compression of airways and vessels, resulting in clinical symptoms and possible complications. On computed tomography (CT) scans, bronchogenic cysts frequently have the appearance of a solid tumor. We describe diagnostic strategy and management for patients with bronchogenic cysts. Methods: Retrospective case study of 11 adults diagnosed with a bronchogenic cyst. The CT scan of all patients was revised and localization, size, Hounsfield Units (HU), and appearance (cystic or solid) of the lesions were reported. Lesions were arbitrarily considered cystic or solid when the radiographic density was below or above 20 HU, respectively. Results: Eleven adults with a bronchogenic cyst were followed for at least 2 years after diagnosis. Eight of 11 detected lesions were judged as a solid lesion, based on the radiographic density (in HU) on CT images. Nine of 11 patients were treated by surgical resection. Two asymptomatic patients were not operated and remained asymptomatic without enlargement of the cysts during 2 years follow-up. Complications of resection were post-operative bleeding (n = 1), recurrent pneumothorax (n = 1), and recurrence of the cyst (n = 1). No mortality was observed. Conclusion: Bronchogenic cysts are frequently mistaken for a solid mass on CT scans. Further differentiation can be made by MRI or EUS when CT is inconclusive.