Ultrasound-guided Fine Needle Aspiration Biopsy of Pleural-based Intrathoracic Lesions

Background: Pleural-based intrathoracic lesions pose a diagnostic challenge. Image-guided percutaneous biopsy with fluoroscopy, computed tomography (CT) scan, and ultrasound (US) have been used to establish a diagnosis. We report the yield of US-guided fine needle aspiration biopsy (FNAB) of these lesions at our center. Methods: Twenty patients with pleural-based intrathoracic lesions underwent US-guided FNAB. All were considered to have an unresectable malignant process based on clinical evaluation. Nineteen patients had pleural-based parenchymal lesion and 1 had an anterior mediastinal mass touching the chest wall. Results: Twenty patients underwent 21 US-guided FNAB procedures. A final diagnosis was established in all the patients: 19 malignancies and 1 benign lesion. US-guided FNAB established a diagnosis of malignancy in 17 of 19 patients (89.5%) in the first attempt. In 1 patient, a diagnosis of malignancy was made on a repeat US-guided FNAB, increasing the overall yield to 18 of 19 (95%). In 1 patient with a nondiagnostic US-guided FNAB, a diagnosis of malignancy was established with CT scan-guided FNAB. US-guided FNAB was able to diagnose 15 of 16 cases of non-small cell carcinoma and 3 of 3 (100%) small cell carcinoma. In 1 patient with benign lesion, US-guided FNAB showed pulmonary macrophages. This patient was diagnosed as having pneumonia after antibiotic therapy and repeat CT scan showed complete resolution. For a diagnosis of malignancy, US-guided FNAB had 94.7% sensitivity, 100% specificity, 95% diagnostic accuracy, 100% positive predictive value, and 50% negative predictive value. There were no major complications. Conclusions: US-guided FNAB of pleural-based intrathoracic lesions is a rapid, simple, and safe procedure with a high yield for malignancy.