Ultrasound-guided transthoracic needle biopsy of the lung: sensitivity and safety variables

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.

Automated summary

This study found that factors such as pleural contact length, lesion size, and core needle diameter are associated with the sensitivity and complication rates of ultrasound-guided transthoracic needle biopsy (US-TTNB).