Simon Lemieux1,2, Taehoo Kim3, Olivier Pothier-Piccinin3, Louis-Charles Racine4,3, Faraz Firoozi3, Maxime Drolet3, Sergio Pasian4,3, Kevin F Kennedy5, Steeve Provencher3,6, Paula Ugalde3,6. 1. Department of Radiology and Nuclear Medicine, Université Laval, Québec City, Québec, Canada. simon.lemieux.9@ulaval.ca. 2. Québec Heart and Lung Institute Research Center, Université Laval, Québec City, Québec, Canada. simon.lemieux.9@ulaval.ca. 3. Québec Heart and Lung Institute Research Center, Université Laval, Québec City, Québec, Canada. 4. Department of Radiology and Nuclear Medicine, Université Laval, Québec City, Québec, Canada. 5. Saint Luke's Mid America Heart Institute, University of Missouri-Kansas City, Kansas City, MO, USA. 6. Department of Pulmonology and Thoracic Surgery, Québec Heart and Lung Institute, Québec City, Québec, Canada.
Abstract
OBJECTIVES: Variables affecting the performance of ultrasound-guided transthoracic needle biopsy (US-TTNB) are not well established. We examined clinical and imaging variables affecting the sensitivity and the complication rates of US-TTNB. METHODS: We retrospectively reviewed a consecutive series of 528 US-TTNBs performed from 2008 to 2017. Univariate analyses were used to assess the influence of clinical and imaging variables on sensitivity and complication rates. Multivariate logistic regression was used to account for possible confounding variables. RESULTS: In 397 malignant lesions, the sensitivity of US-TTNB was 72% (95% CI 68-77%; 285/397). The overall pneumothorax rate was 15% (95% CI 12-18%; 77/528), leading to a chest tube in 2% (95% CI 1-3%; 9/528). Multivariate analysis showed that increasing pleural contact length (up to 30 mm) was associated with increased sensitivity (OR 1.08 per mm; 95% CI 1.04-1.12; p < 0.001), and pleural contact length (OR 0.98 per mm; 95% CI 0.97-0.99; p = 0.013), lesion size (OR 0.98 per mm; 95% CI 0.96-0.99; p = 0.006), and core needle diameter of 18G (OR 0.47 as compared with 20G; 95% CI 0.26-0.83; p = 0.010) were associated with a decreased pneumothorax rate. Graphical inspection of cubic splines showed that the probability of a positive biopsy rose sharply with increasing pleural contact length up to 30 mm and was stable thereafter. A similar, but inverse, relationship was observed for the probability of a pneumothorax. CONCLUSION: Pleural contact length is a key variable predicting the sensitivity of US-TTNB and pneumothorax rate after US-TTNB. Lesion size also predicts pneumothorax rates. KEY POINTS: • US-TTNB has a high sensitivity and a low complication rate for pleural and pulmonary lesions with pleural contact. • Pleural contact length is a key variable predicting the sensitivity of US-TTNB and pneumothorax rate after US-TTNB. • This study suggests that relying on US-TTNB may not be optimal for lesions < 10 mm for which the risk of pneumothorax is as high as the chance of obtaining diagnosis.
OBJECTIVES: Variables affecting the performance of ultrasound-guided transthoracic needle biopsy (US-TTNB) are not well established. We examined clinical and imaging variables affecting the sensitivity and the complication rates of US-TTNB. METHODS: We retrospectively reviewed a consecutive series of 528 US-TTNBs performed from 2008 to 2017. Univariate analyses were used to assess the influence of clinical and imaging variables on sensitivity and complication rates. Multivariate logistic regression was used to account for possible confounding variables. RESULTS: In 397 malignant lesions, the sensitivity of US-TTNB was 72% (95% CI 68-77%; 285/397). The overall pneumothorax rate was 15% (95% CI 12-18%; 77/528), leading to a chest tube in 2% (95% CI 1-3%; 9/528). Multivariate analysis showed that increasing pleural contact length (up to 30 mm) was associated with increased sensitivity (OR 1.08 per mm; 95% CI 1.04-1.12; p < 0.001), and pleural contact length (OR 0.98 per mm; 95% CI 0.97-0.99; p = 0.013), lesion size (OR 0.98 per mm; 95% CI 0.96-0.99; p = 0.006), and core needle diameter of 18G (OR 0.47 as compared with 20G; 95% CI 0.26-0.83; p = 0.010) were associated with a decreased pneumothorax rate. Graphical inspection of cubic splines showed that the probability of a positive biopsy rose sharply with increasing pleural contact length up to 30 mm and was stable thereafter. A similar, but inverse, relationship was observed for the probability of a pneumothorax. CONCLUSION: Pleural contact length is a key variable predicting the sensitivity of US-TTNB and pneumothorax rate after US-TTNB. Lesion size also predicts pneumothorax rates. KEY POINTS: • US-TTNB has a high sensitivity and a low complication rate for pleural and pulmonary lesions with pleural contact. • Pleural contact length is a key variable predicting the sensitivity of US-TTNB and pneumothorax rate after US-TTNB. • This study suggests that relying on US-TTNB may not be optimal for lesions < 10 mm for which the risk of pneumothorax is as high as the chance of obtaining diagnosis.