Transbronchial Needle Aspiration for the Diagnosis and Management of Bronchogenic Cysts

Researchers have confirmed that bronchoscopy is a good tool for the diagnosis of bronchogenic cysts, and that therapeutic aspiration is an alternative to surgery for adults who are unfit or are reluctant to have surgery; however, transbronchial needle aspiration (TBNA) as a primary method of managing mediastinal bronchogenic cysts may not be the best modality for all patients.

Venkata Maturu MD, DM, and colleagues completed a review of the literature pertaining to TBNA in the diagnosis and management of bronchogenic cysts at the Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research in Chandigarh, India. Their findings were published in the Journal of Bronchology and Interventional Pulmonology in Volume 22, Number 3, in July 2015.

A systematic search of both PubMed and EmBase brought up 26 studies involving TBNA of bronchogenic cysts. The researchers narrowed the results to those describing the role of endobronchial ultrasound (EBUS) and TBNA in the management of mediastinal bronchogenic cysts in adults.

Bronchogenic cysts are the most common type of mediastinal cysts in adults. The bronchogenic cyst usually contains clear fluid, and the patient may either be asymptomatic or have nonspecific respiratory symptoms. Chest X-Rays are not useful in diagnosing bronchogenic cysts, in part because it is not possible to distinguish between a solid and cystic lesion. CT scans do not reveal the exact size of mediastinal cysts due to their location and other structures. MRI is rarely used in the diagnosis of bronchogenic cysts because it is uncomfortable for the patient without adding much information.

The most accurate, nonsurgical method of diagnosing a mediastinal cyst is aspiration of the fluid from the cyst. There are various ways to perform such aspiration, but the researchers concluded that TBNA, either conventionally or EBUS-guided, appears to be the safest method.

Experts do not agree about the best approach to managing bronchogenic cysts. Some argue that surgical removal is the best way to ensure that malignancy does not occur or the cyst does not enlarge and compress surrounding tissues and organs. Those who favor a more conservative approach argue that the surgical morbidity rate of 20% is substantial and mediastinal cysts have a much lower tendency than other types of cysts to become infected.

Bronchoscopy offers a good tool to diagnose bronchogenic cysts, and the diagnosis can be confirmed through TBNA of the cyst fluid. Patients who are not good candidates for surgery can be treated with the alternative therapeutic TBNA, as long as they are closely monitored.