Computed tomography-guided transthoracic needle aspiration biopsy of intrapulmonary lesions: Utility of a liquid-based cytopreparatory technique

Objective: To determine if a ThinPrep processor (Cytyc Corporation, Boxborough, Massachusetts, U.S.A.) could be used to improve diagnostic accuracy in the absence of a cytopathologist at the time of computed tomography-guided (CT-guided) transthoracic needle aspiration biopsy (TNAB) of the lung. Study Design: Ninety-two patients (59 men and 33 women who were 26-85 years old) underwent CT-guided TNAB. The aspirated specimen was prepared with the ThinPrep cytopreparatory technique for cytologic evaluation. The final histologic diagnoses were based on the pathologic material obtained from a cutting needle biopsy, bronchoscopic biopsy and surgical excision and the on clinical follow-up (mean, 12 months). On this basis, the accuracy, sensitivity and specificity of TNAB for malignant lesions were calculated by comparing the diagnoses obtained from percutaneous transthoracic needle aspiration with the final diagnoses using a χ² test. Results: Of the intrapulmonaiy masses for which a final diagnosis was made, 56 (60.9%) were malignant and 36 (39.1%) benign. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of malignancy were 92%, 87.5%, 100%, 100% and 80%, respectively. Conclusion: CT-guided TNAB using ThinPrep provided excellent diagnostic accuracy and was useful because this technique shows less air-diying artifact and can separate cells and blood clots on the slides.