Assessment of Tissue Adequacy by EBUS in Conjunction with PET Scan and Operator’s Experience

Abstract

Mediastinal lymph node assessment is a crucial step in non-small cell lung cancer staging. Positron emission tomography (PET) has been the gold standard for the assessment of mediastinal lymphadenopathy, though it has limited specificity. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is quick, accurate, and a less invasive method for obtaining a diagnostic sample in contrast to mediastinoscopy. We performed a retrospective chart analysis of 171 patients to assess the adequacy of tissue obtained by EBUS for diagnosis and molecular profiling as well as the assessment of staging and lymph node (LN) stations diagnostic yield, in correlation to PET scan and the operator’s level of experience. A significantly increased tissue adequacy was observed based on the operators’ experience, with the highest adequacy noted in trained Interventional Pulmonologist (IP) (100%), followed by >5 years of experience (93.33%), and 88.89% adequacy with <5 years of experience (p = 0.0019). PET-CT scan 18F-fluorodeoxyglucose (FDG) uptake in levels 1, 2, and 3 LN had a tissue adequacy of 76.67%, 54.64%, and 35.56%, respectively (p = 0.0009). EBUS bronchoscopy method could be used to achieve an accurate diagnosis, with IP-trained operators yielding the best results. There is no correlation with PET scan positivity, indicating that both PET and EBUS are complementary methods needed for staging.

Insufficient endobronchial ultrasound‐guided transbronchial needle aspiration specimens. When and why? The analysis of criteria and reasons behind the insufficient specimens

“…Therefore, to allow for more consistent implementation in the clinical and scientific community, efforts should be made to set up a standard definition of "adequate" in regard to tissue sampling. 31 The ROM for the insufficient samples were 10.9% (5/46), for the benign samples 15.7% (17/108), for the suspicious of malignancy samples 92.0% (23/25), and the ROM for the malignant samples 100% (69/69). The results differ slightly from the literature.…”

“…This might be due to the anatomical difficulty for inexperienced operator to position the scope against the bronchial wall with a small ultrasound window angle (50–60°) 30 . Also, a previous study shows that diagnostic accuracy for operator with less than 5 years of experience is 88.89% 31 . There were no studies of sampling accuracy of subcarinal location published.…”

“…30 Also, a previous study shows that diagnostic accuracy for operator with less than 5 years of experience is 88.89%. 31 There were no studies of sampling accuracy of subcarinal location published.…”

“…If a diagnosis can be made, a sample is generally considered to be adequate, but this term leaves room for interpretation and is nonuniform. Therefore, to allow for more consistent implementation in the clinical and scientific community, efforts should be made to set up a standard definition of “adequate” in regard to tissue sampling 31 …”