Bronchogenic Cyst

In pediatric patients: bronchogenic cysts may cause life-threatening compressive symptoms.[8]

In adults: bronchogenic cysts are often incidental radiologic findings.[9] Pulmonary bronchogenic cysts are more likely to be symptomatic than mediastinal cysts, and 86.4% of symptomatic patients have a complicated cyst.[10]

• Symptoms are secondary to cyst infection or compression of adjacent structures.[11]
• Fistulized bronchogenic cysts cause cough, fever, sputum production, and hemoptysis.
• Non-fistulized bronchogenic cysts are usually responsible for chest pain.[12]
• Pericystic pneumonitis or pneumonia in the adjacent compressed lung are responsible for fever and shortness of breath.[4]

Chest radiograph: 

• Pulmonary bronchogenic cysts: 
  • Sharply defined, solitary, round or oval opacities, usually the lower lobe. They can present as a homogeneous water density, as an air-filled cyst, or with an air-fluid level. Abnormalities in the surrounding lung parenchyma, atelectasis or consolidation may occur and may make the diagnosis more difficult.[13]

• Mediastinal bronchogenic cysts:
  • Homogeneous, smooth, solitary, round or ovoid masses usually in the middle mediastinum.[13][3]

Computed tomography scan:

CT is the investigation of choice. The CT density of bronchogenic cysts is variable from typical water density to high density related to blood, increased calcium content, anthracotic pigment, or increased protein content of the fluid.[13][3]

Magnetic resonance imaging (MRI):

Magnetic resonance imaging is better than CT scan at delineating anatomic relations and the definition of the cyst. The MRI appearance depends on the cyst’s content. On T1-weighted images, the intrinsic signal intensity varies from low to high, depending on the cyst contents. T2-weighted images show high signal intensity. Enhancement after contrast injection is frequently absent.[13][3]

The treatment of patients with bronchogenic cysts depends on symptoms at presentation and the patient’s age. Surgical resection alleviates symptoms, prevents complications and establishes the diagnosis of bronchogenic cysts.

Symptomatic cysts should be resected either by thoracotomy or via video-assisted thoracoscopy regardless of patient age unless surgical risks are unacceptably high.[11][3]

There has been a recent rise in the use of thoracoscopic techniques for resection of bronchogenic cysts in adults. The benefits of thoracoscopy include decreased scarring, reduced pain, and shorter hospitalization. Complicated bronchogenic cysts usually require thoracotomy for more extensive resection.[10]

The resection must be complete because of the risk of recurrence after incomplete surgical removal. The treatment of asymptomatic bronchogenic cysts remains controversial. Most authors seem to advocate a surgical approach to prevent complications.[9][3]

Intrapulmonary bronchogenic cysts:

Lobectomy is the procedure of choice. However, in peripheral bronchogenic cysts or patients with limited lung function, a conservative procedure as a total pericystectomy, a wedge resection, or segmentectomy are recommended. 

Mediastinal bronchogenic cysts:

The presence of adhesions especially in complicated forms of mediastinal bronchogenic cysts can lead to incomplete resection. Thus, resection or destruction of the mucosa is a requirement to prevent accumulation of fluid and late recurrence.[14]

An alternative option for bronchogenic cysts is close imaging surveillance to ensure temporal stability.

Radiological differential diagnosis:

• Lung abscess
• Hydatid cyst
• Fungal disease
• Tuberculosis
• Infected bullae
• Vascular malformations
• Neoplasms

Histological differential diagnosis:

• Cystic teratoma
• Bronchopulmonary sequestration
• Esophageal cysts
• Chronic healed abscess

The prognosis of bronchogenic cysts after surgical excision is excellent. In case of incomplete excision, late recurrences can occur.[15] A recent study reviewing 102 patients treated for bronchogenic cysts, the estimated mean morbidity and mortality was 20%.[16]

According to some authors, bronchogenic cysts lead to complications in 45% of patients, but complications do not increase morbidity and death.[17]

Complications of bronchogenic cysts include:

• Tracheobronchial compression and pulmonary infections,

• Rare complications comprise[18][19][20][21][22][23][22][21][20]

  • Pneumothorax

  • Pleurisy

  • Superior vena cava syndrome

  • Stenosis of pulmonary artery

  • Arrhythmias

  • Fatal air embolism in an airplane passenger

  • Malignant transformation

  • Fatal myocardial infarction (MI) secondary to compression of the left main coronary artery

Bronchogenic are rare lesions. In children, they often tend to be symptomatic, but in adults, they are often an incidental finding. However, because their diagnosis and management are not straightforward, the disorder is best managed by an interprofessional team that includes a radiologist, pediatrician, thoracic surgeon, and a pulmonologist. Specialty trained nurses in perianesthesia, operating room, and critical care work with the team to monitor patients, communicate with the patient's families, and provide feedback about issues in care. [Level 5]