Endobronchial Ultrasound–Guided Transbronchial Fine-Needle Aspiration

Abstract

Endobronchial ultrasound-guided transbronchial fine-needle aspiration (EBUS-TBNA) is a new technique that facilitates cytologic sampling of mediastinal lymph nodes. We describe our initial experience with this method, including adequacy assessment, impact on cytopathologists' work, and diagnostic pitfalls. There were 229 EBUS-TBNA samples obtained from 100 patients; a mean of 22 minutes was spent with an average of 3 passes performed and 6 slides prepared per site. Of 193 aspirates, 5 were categorized as atypical, 54 as positive, and 134 as negative for malignancy; 36 (15.7%) aspirates were nondiagnostic. We found EBUS-TBNA to have a high specificity (100%) and good sensitivity (86%) in our institution, in which a cytopathologist is available on-site to ensure sample adequacy. Most true-negative samples had moderate to abundant lymphocytes, confirming lymphocyte numbers as a marker of adequacy. For pathologists, this was a relatively time-consuming procedure. Recognizing bronchial contamination, especially with metaplastic or dysplastic cells, is important for avoiding diagnostic pitfalls.

Improved Efficacy of Endobronchial Ultrasound-Guided Fine-Needle Aspiration Biopsy in Comparison to Endobronchial Ultrasound-Guided Miniforceps Biopsy

“…In a study of 77 patients in the Netherlands, for more than 50% of patients with lung cancer who were suspected to have mediastinal lymph node metastasis, EBUS-TBNA was deemed sufficient enough to make the need for mediastinoscopy unnecessary [20]. Mediastinoscopy, although previously described as the ‘gold standard', is more invasive and poses significant risks to the patient compared to EBUS-FNA, which is much safer and cheaper [5]. …”

“…However, over time there has been an increased demand for less invasive procedures for achieving the aforementioned goals. Conventional transbronchial needle aspiration (TBNA) for a while served this purpose until it was replaced with the more refined method of endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA) [5]. As a result, the diagnostic yield for such cases increased from 71% (for conventional TBNA) to 80% (for EBUS-FNA) with a p value <0.05 [6].…”

“…Although mediastinoscopy with biopsy remains the standard procedure for evaluating mediastinal lymph nodes and pulmonary lesions in many medical centers [5,10], EBUS-FNA/MFB has emerged as a quintessential minimally invasive tool for accessing mediastinal lymph nodes and pulmonary lesions for the purpose of cancer staging and primary diagnosis, respectively. Mediastinoscopy is limited to accessing only stations 1, 2, 3, 4 and 7 mediastinal lymph nodes [11].…”

“…One of the main deficiencies for the EBUS-FNA modality is its inability to access lymph nodes in the aortopulmonary window, para-aortic station, inferior pulmonary ligament and para-esophageal stations [15]. However, with a reported sensitivity and specificity of 88-93 and 100% [15,16] for EBUS-FNA compared to 84.6 and 100% for mediastinoscopy, respectively [2], and a positive predictive value of more than 90% for EBUS [5], EBUS-FNA has become the initial modality of choice for many clinicians.…”

Influence of trainee involvement on procedural characteristics for linear endobronchial ultrasound

“…The rates of specimen adequacy on a per‐lymph node basis (defined as the proportion of specimens with a sufficient number of lymphocytes or with a specific diagnosis)17 were compared between the two groups. Finally, the diagnostic yields on a per‐patient basis were compared (defined as the proportion of subjects in whom a specific diagnosis was established by EBUS TBNA; inadequate specimens and those containing only benign lymphocytes were considered non‐diagnostic).…”