Ultrasound-guided lung biopsy with coaxial technique: pleural contact length affects the occurrence of pneumothorax after first puncture

Purpose To assess prebiopsy characteristics influencing the occurrence of pneumothorax after first puncture of ultrasound (US)-guided lung biopsy with coaxial technique. Materials and methods From January 2007 to September 2018, 180 peripheral lung lesions in 174 patients who underwent B-mode US-guided lung biopsy with coaxial technique at single institution were included in this study. Technical success was defined as the ability to make a diagnosis using the acquired sample with/without an adverse event of pneumothorax. Statistical analyses of prebiopsy characteristics were performed to identify the most important cutpoint and to evaluate the effect on diagnostic accuracy. Results Of the 180 lesions (mean size, 37 mm ± 26.2; mean pleural contact length, 38.2 mm ± 34.4), technical success rate was 97.2% (175/180 lesions) and diagnostic accuracy rate was 91.6% (165/180 lesions). Pneumothorax occurred immediately after first puncture for seven of 180 lesions. Classification and regression tree analysis and Fisher’s exact test showed the proportion of the pneumothorax immediately after first puncture was higher in lesions with pleural contact length less than 9.78 mm (p = 0.002). No significant difference was shown between the pneumothorax and non-pneumothorax after first puncture in technical success and final diagnosis success rate. Conclusion Pleural contact length affects the occurrence of pneumothorax after first puncture of US-guided lung biopsy with coaxial technique.

Radiomic signature based on CT imaging to distinguish invasive adenocarcinoma from minimally invasive adenocarcinoma in pure ground-glass nodules with pleural contact

Background Pure ground-glass nodules (pGGNs) with pleural contact (P-pGGNs) comprise not only invasive adenocarcinoma (IAC), but also minimally invasive adenocarcinoma (MIA). Radiomics recognizes complex patterns in imaging data by extracting high-throughput features of intra-tumor heterogeneity in a non-invasive manner. In this study, we sought to develop and validate a radiomics signature to identify IAC and MIA presented as P-pGGNs. Methods In total, 100 patients with P-pGGNs (69 training samples and 31 testing samples) were retrospectively enrolled from December 2012 to May 2018. Imaging and clinical findings were also analyzed. In total, 106 radiomics features were extracted from the 3D region of interest (ROI) using computed tomography (CT) imaging. Univariate analyses were used to identify independent risk factors for IAC. The least absolute shrinkage and selection operator (LASSO) method with 10-fold cross-validation was used to generate predictive features to build a radiomics signature. Receiver-operator characteristic (ROC) curves and calibration curves were used to evaluate the predictive accuracy of the radiomics signature. Decision curve analyses (DCA) were also conducted to evaluate whether the radiomics signature was sufficiently robust for clinical practice. Results Univariate analysis showed significant differences between MIA (N = 47) and IAC (N = 53) groups in terms of patient age, lobulation signs, spiculate margins, tumor size, CT values and relative CT values (all P < 0.05). ROC curve analysis showed, when MIA was identified from IAC, that the critical value of tumor length diameter (TLD) was1.39 cm and the area under the ROC curve (AUC) was 0.724 (sensitivity = 0.792, specificity = 0.553). The critical CT value on the largest axial plane (CT-LAP) was − 597.45 HU, and the AUC was 0.666 (sensitivity = 0.698, specificity= 0.638). The radiomics signature consisted of seven features and exhibited a good discriminative performance between IAC and MIA, with an AUC of 0.892 (sensitivity = 0.811, specificity 0.719), and 0.862 (sensitivity = 0.625, specificity = 0.800) in training and testing samples, respectively. Conclusions Our radiomics signature exhibited good discriminative performance in differentiating IAC from MIA in P-pGGNs, and may offer a crucial reference point for follow-up and selective surgical management.

Ultrasound- Versus CT-Guided Subpleural Lung and Pleural Biopsy: An Analysis of Wait Times, Procedure Time, Safety, and Diagnostic Adequacy

Purpose: To compare the wait times, safety, and diagnostic adequacy of computed tomography (CT)–guided percutaneous lung biopsies with ultrasound (US) guidance for subpleural lung and pleural lesions. Methods: Consecutive CT- and US-guided biopsies performed at our institution between January 2018 and January 2019 were retrospectively reviewed. Biopsy wait times, lesion size, degree of pleural contact, procedure duration, number of needle passes, complications, and pathologic diagnosis were recorded and compared. Results: A total of 158 biopsies of subpleural or pleural-based lesions were reviewed. Forty-three cases utilized US guidance, while 115 cases used CT, 41 with conventional CT (CCT), and 74 with cone-beam CT guidance (CBCT). Overall, the mean lesion maximum axial diameter and length of pleural contact for US-guided biopsies was greater than for CT (4.8 ± 2.6 cm vs 3.2 ± 1.9 cm and 4.0 ± 2.5 cm vs 2.6 ± 1.7 cm, respectively, P < .001). Wait times for US-guided biopsies were significantly shorter than CCT by 10.9 days on average while being equivalent to CBCT. Procedure time was shorter for lesions localized with US than CT (29.5 ± 16.4 minutes vs 37.6 ± 19.5 minutes, P = .007) despite CT using less needle passes per lesion (3.5 ± 1.1 vs 3.1 ± 0.8, P = .034). Sample adequacy was equivalent for both modalities (88% for US and 92% for CT). The frequency of pneumothoraces was similar between US (12%) and CT (15%). Conclusion: Ultrasound and CT guidance have similar safety and diagnostic adequacy for subpleural lung and pleural biopsies. Ultrasound guidance has shorter wait and procedure times.