Endobronchial Ultrasound-Guided Transbronchial Fine Needle Aspiration: A Sensitive and Specific Diagnostic Technique
AT Turk, WA Bulman, A Saqi. Columbia University, New York
Background: Endobronchial ultrasound (EBUS) with transbronchial fine needle aspiration (TFNA) is being used increasingly for diagnosis of mediastinal/pulmonary lesions, and as a less invasive alternative to mediastinoscopy for sampling lymph nodes and staging patients with confirmed or suspected lung carcinoma. Relative to mediastinoscopy, the sample obtained with TFNA is small. The aim of the current study was to determine (1) the sensitivity and specificity of EBUS TFNA for neoplastic and non-neoplastic processes, and (2) the ability to provide specific diagnosis (e.g. small cell carcinoma (SCC), adenocarcinoma (ADCA), squamous cell carcinoma (SCCA), metastasis (METS) versus non-small cell carcinoma (NSCC)) to guide appropriate management.
Design: Computerized records and clinical follow-up of EBUS TFNAs spanning a nine-month period were reviewed. Cases were categorized as diagnostic (non-neoplastic and neoplastic) or non-diagnostic, and sensitivity and specificity were calculated. For the diagnostic neoplastic cases, availability of additional modalities (cell blocks and immunohistochemistry) contributing to specific diagnosis were assessed.
Results: A total of 49 EBUS procedures were performed, and follow-up data were available for 42 cases, which form the basis of the study. Of these 42 cases, 28 were diagnostic, including 2 non-neoplastic (granulomatous processes) and 26 neoplastic cases. There were 26 true positives (malignant), 4 false negatives, 12 true negatives, and 0 false positives. The sensitivity and specificity were 87% and 100%, respectively. Specific diagnoses of 1 SCC (4%), 12 ADCA (46%), 9 SCCA (35%), and 2 METS (8%), and non-specific diagnoses of 2 NSCC (8%) were rendered. Cell blocks and immunohistochemical studies were used for 23/26 and 16/26 neoplastic cases (respectively); cell blocks were also used for 1 of 2 non-neoplastic cases.
Conclusions: EBUS TFNA is a sensitive and highly specific procedure. Additionally, on-site assessment by the cytology staff is valuable for triaging specimens for cell blocks and additional subtyping of neoplasms. Overall, the results demonstrate EBUS TFNA is an effective and minimally invasive procedure with the ability to provide specific results with small samples.
Tuesday, March 23, 2010 2:15 PM
Platform Session: Section D, Tuesday Afternoon