The diagnostic yield and safety of ultrasound-assisted transthoracic fine-needle aspiration of drowned lung.

BACKGROUND: Proximal lung tumors, though not discernable by means of transthoracic ultrasound (US), may cause varying degrees of pulmonary collapse and postobstructive pneumonitis which may give rise to a 'drowned lung' appearance on chest computed tomography (CT) and US. The diagnostic yield for malignancy of US-assisted transthoracic fine-needle aspiration (FNA) of these areas of drowned lung is unknown.

OBJECTIVES: We aimed to explore the feasibility of US-assisted FNA in this setting by prospectively investigating its diagnostic yield and safety.

METHODS: We enrolled 31 patients (aged 59.4 ± 9.7 years, 17 males) with central tumors and secondary drowned lung on CT scan. A respiratory physician performed transthoracic US to identify the target drowned lung tissue. Three US-assisted superficial FNA passes (≤20 mm from the pleura) were followed by 3 deeper FNA passes (>20 mm) aimed in the direction of a visible or approximated central mass. Rapid on-site evaluation of specimens was used.

RESULTS: Superficial FNA was diagnostic in 11 patients (35.5%), whereas deeper FNA was diagnostic in 23 patients (74.2%, p = 0.002). Deeper FNA confirmed malignancy in all cases with diagnostic superficial FNA. We observed no pneumothoraces or major hemorrhage. All patients were ultimately diagnosed with malignancy (bronchogenic carcinoma, n = 30; lymphoma, n = 1).

CONCLUSIONS: US-assisted FNA of drowned lung has an acceptable diagnostic yield and is safe.