Transaortic fine needle aspiration of lung cancer and mediastinal lymph nodes

BACKGROUND AND OBJECTIVES: Obtaining a tissue diagnosis from lung tumor or mediastinal lymph node located lateral to the aorta (para-aortal) is a diagnostic challenge because of the interposition of the aorta. Invasive surgical procedures such as mediastinotomy, thoracotomy, or video-assisted thoracic surgery are required for the diagnosis of these lesions. Lymph nodes on the “far-side” of major blood vessels can be visualized by endoscopic ultrasound (EUS); however, fine needle aspiration (FNA) is avoided due to concern for bleeding complications. Tumors and mediastinal lymph nodes located in the para-aortic region can easily be visualized by esophageal EUS, because the aorta provides an excellent medium to transfer ultrasound waves. The objective of the study is to evaluate the feasibility, yield, and safety of EUS-guided transaortic FNA of lung tumors and para-aortic lymph nodes. METHODS: A retrospective case series of 12 consecutive patients with suspected lung cancer or tuberculosis who underwent transaortic FNAC during a study period of 7 years. Based on computed tomography/positron-emission tomography imaging, a transesophageal FNAC performed through the aorta was considered as the only option to diagnose or stage these patients by means of a minimally invasive procedure. Seven patients had left-sided lung mass. Four patients has enlarged para-aortic lymph node, suspicious for IASLC Stations 5 (n = 1) and 6 (n = 3). EUS was performed with a linear echoendoscope. All aspirates were obtained under real-time US-guided FNA by using a 22/25-gauge needle. A single real-time FNA of the lung mass or lymph node was performed. RESULTS: The final diagnosis was known in 11 patients (5 non-small cell lung carcinoma [SCLC], 2 SCLC, 3 tuberculosis, and 1 thymolipoma). EUS-FNA established diagnosis in 9 of 12 patients (75%). One procedure was abandoned due to complication. CONCLUSION: This case series demonstrates the feasibility and probable safety of single EUS guided transaortic aspiration in para-aortic lesions. The diagnostic yield is 75%. Clearly, further study and very careful selection by expert EUS operators are needed before this procedure can be routinely recommended. Advantages of this procedure include day care procedure, less invasive than surgical procedures, low-cost, good diagnostic yield and can be performed in poor surgical candidate. Limitations includes single-center study, requires EUS expertise, more data are required. At present, transaortic FNA should only be performed in the absence of alternative minimally invasive diagnostic procedures.