Diagnostic Yield of Transbronchial Cryobiopsy Guided by Radial Endobronchial Ultrasound and Fluoroscopy in the Radiologically Suspected Lung Cancer: A Single Institution Prospective Study

The Diagnostic Efficiency and Safety of Transbronchial Lung Cryobiopsy Using 1.1-mm Cryoprobe in Diagnosing Interstitial Lung Disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is increasingly used to diagnose interstitial lung disease (ILD). The 1.1-mm cryoprobe has recently been available in clinical practice. The diagnostic yield and safety of TBLC using a 1.1-mm cryoprobe need to be confirmed.

METHODS

A prospective, randomized controlled trial was conducted in patients with suspected ILD and randomly assigned to 1.1-mm and 1.9-mm cryoprobe groups. The primary outcome was the diagnostic yield of multidisciplinary discussion. Secondary outcomes were sample quality and incidence of complications. The tension and stress effects during TBLC onto the target lobe caused by 1.1-mm and 1.9-mm cryoprobes were also evaluated using finite element analysis.

RESULTS

A total of 224 patients were enrolled. No significant differences were observed in the diagnostic yield (80.4% vs. 79.5%, p = 0.845) and sample quality scores (5.73 ± 0.64 vs. 5.66 ± 0.77; p = 0.324) between the 1.9-mm cryoprobe group and 1.1-mm cryoprobe group. The average surface areas of samples in 1.1-mm cryoprobe group were smaller, while no difference in sample weights was observed. A decreased incidence of moderate bleeding was found in the 1.1-mm cryoprobe group (17.0% vs. 6.2%, p = 0.027), while there was no difference in the incidence of the pneumothorax, there was a trend to higher rate of pneumothorax in 1.1-mm group. In finite element analysis, the 1.1-mm cryoprobe required the largest tension and produced the largest stress.

CONCLUSION

Compared with a 1.9-mm cryoprobe, there was no difference in specimen quality or diagnostic rate but smaller sample size with a 1.1-mm cryoprobe. There was a decreased risk of moderate bleeding, but a trend towards increased risk for pneumothorax with 1.1-mm cryoprobe.

TRAIL REGISTRATION

Clinicaltrials.gov identifier NCT04047667; registered August 4, 2019.

Transbronchial lung cryobiopsy for peripheral pulmonary lesions. A narrative review

An increasing number of peripheral pulmonary lesions (PPLs) requiring tissue verification to establish a definite diagnosis for further individualized management are detected due to the growing adoption of lung cancer screening by chest computed tomography (CT), especially low-dose CT. However, the morphological diagnosis of PPLs remains challenging. Transbronchial lung cryobiopsy (TBLC) that can retrieve larger specimens with more preserved cellular architecture and fewer crush artifacts in comparison with conventional transbronchial forceps biopsy (TBFB), as an emerging technology for diagnosing PPLs, has been demonstrated to have the potential to resolve the clinical dilemma pertaining to currently available sampling devices (e.g., forceps, needle and brush) and become a diagnostic cornerstone for PPLs. Of note, with the introduction of the 1.1 mm cryoprobe that will be more compatible with advanced bronchoscopic navigation techniques, such as radial endobronchial ultrasound (r-EBUS), virtual bronchoscopic navigation (VBN) and electromagnetic navigation bronchoscopy (ENB), the use of TBLC is expected to gain more popularity in the diagnosis of PPLs. While much remains for exploration using the TBLC technique for diagnosing PPLs, it can be envisaged that the emergence of additional studies with larger data accrual will hopefully add to the body of evidence in this field.

Development of the Korean Association for Lung Cancer Clinical Practice Guidelines: Recommendations on Radial Probe Endobronchial Ultrasound for Diagnosing Lung Cancer - An Updated Meta-Analysis

PURPOSE

Radial probe endobronchial ultrasound (RP-EBUS) accurately locates peripheral lung lesions (PLLs) during transbronchial biopsy (TBB). We performed an updated meta-analysis of the diagnostic yield of TBB for PLLs using RP-EBUS to generate recommendations for the development of the Korean Association of Lung Cancer guidelines.

MATERIALS AND METHODS

We systematically searched MEDLINE and EMBASE (from January 2013 to December 2022), and performed a meta-analysis using R software. The diagnostic yield was evaluated by dividing the number of successful diagnoses by the total lesion number. Subgroup analysis was performed to identify related factors.

RESULTS

Forty-one studies with a total of 13,133 PLLs were included. The pooled diagnostic yield of RP-EBUS was 0.72 (95% confidence interval [CI], 0.70 to 0.75). Significant heterogeneity was observed among studies (χ2=292.38, p < 0.01, I2=86.4%). In a subgroup analysis, there was a significant difference in diagnostic yield based on RP-EBUS findings (within, adjacent to, invisible), with a risk ratio of 1.45 (95% CI, 1.23 to 1.72) between within and adjacent to, 4.20 (95% CI, 1.89 to 9.32) between within and invisible, and 2.59 (95% CI, 1.32 to 5.01) between adjacent to and invisible. There was a significant difference in diagnostic yield based on lesion size, histologic diagnosis, computed tomography (CT) bronchus sign, lesion character, and location from the hilum. The overall complication rate of TBB with RP-EBUS was 6.8% (bleeding, 4.5%; pneumothorax, 1.4%).

CONCLUSION

Our study showed that TBB with RP-EBUS is an accurate diagnostic tool for PLLs with good safety profiles, especially for PLLs with within orientation on RP-EBUS or positive CT bronchus sign.

Detailed Characterization of the Lung-Gut Microbiome Axis Reveals the Link between PD-L1 and the Microbiome in Non-Small-Cell Lung Cancer Patients

Next-generation sequencing technologies have started a new era of respiratory tract research in recent years. Alterations in the respiratory microbiome between healthy and malignant conditions have been revealed. However, the composition of the microbiome varies among studies, even in similar medical conditions. Also, there is a lack of complete knowledge about lung-gut microbiome interactions in lung cancer patients. The aim of this study was to explore the lung-gut axis in non-small-cell lung cancer (NSCLC) patients and the associations between lung-gut axis microbiota and clinical parameters (CRP, NLR, LPS, CD8, and PD-L1). Lung tissue and fecal samples were used for bacterial 16S rRNA sequencing. The results revealed, for the first time, that the bacterial richness in lung tumor tissue gradually decreased with an increase in the level of PD-L1 expression (p < 0.05). An analysis of β-diversity indicated a significant positive correlation between the genera Romboutsia and Alistipes in both the lung tumor biopsies and stool samples from NSCLC patients (p < 0.05). Survival analysis showed that NSCLC patients with higher bacterial richness in their stool samples had prolonged overall survival (HR: 2.06, 95% CI: 1.025-4.17, p = 0.0426).

Safety and risk factors for bleeding complications of radial probe endobronchial ultrasound-guided transbronchial biopsy

BACKGROUND

Radial probe endobronchial ultrasound (radial EBUS) is widely used to diagnose pulmonary lesions; however, the diagnostic value of radial EBUS-guided transbronchial biopsy (TBB) varies, and its complications (especially the risk of bleeding) are not properly understood.

OBJECTIVES

In this study, we evaluated the diagnostic performance and rate of complication of this procedure, and investigated the risk factors associated with the procedure-related bleeding events.

DESIGN

A retrospective cohort study.

METHODS

This was a retrospective study that included consecutive patients who underwent radial EBUS-guided TBB. Radial EBUS was performed under moderate sedation in inpatients or outpatients. The severity of bleeding was graded using the standardized definitions of bleeding.

RESULTS

Of 133 patients (median age, 69 years; men 57.1%) included, 41 were outpatients (30.8%). The diagnostic accuracy, sensitivity, and specificity for malignancy were 76.1% (89/117), 71.1% (69/97), and 100% (20/20), respectively. The diagnostic accuracy ranged from 66.9% to 79.0%, depending on the classification of undiagnosed cases as either false negatives or true negatives. Twenty-seven patients (20.3%) developed complications (pneumothorax, 3; pneumonia, 5; complicated pleural effusion, 2; bleeding event grade 2 or higher, 21). Of the 41 outpatients, two developed complications (pneumothorax without intervention, 1; grade 2 bleeding event, 1). Of the 21 patients (15.8%) with procedure-related bleeding events, 18 had grade 2, and three had grade 3 bleeding complications. In multivariate analysis, a large size of ⩾30 mm (adjusted odds ratio (OR), 5.09; p = 0.03) and central lesion (adjusted OR, 3.67; p = 0.03) were significantly associated with the risk of grade 2 or higher bleeding events.

CONCLUSION

Our results suggest that radial EBUS-guided TBB is an accurate and safe method for diagnosing pulmonary lesions. Clinically significant procedure-related bleeding was rare. The central location and larger size (⩾30 mm) of pulmonary lesions were risk factors for grade 2 or higher bleeding events.

The efficacy and safety of radial endobronchial ultrasound-guided transbronchial lung cryobiopsy in the diagnosis of lung disease

Background

Transbronchial lung cryobiopsy (TBLC) is a novel technology in which a cryoprobe is used to obtain large tissue samples from the lungs of patients with interstitial lung diseases (ILDs) and peripheral pulmonary lesions (PPLs). We aimed to determine the efficacy and safety of TBLC in the diagnosis of peripheral lung diseases in the Endoscopy Center of Shanghai Pulmonary Hospital. Further, the application value of radial endobronchial ultrasound (R-EBUS) used to determine the optimal area for cryobiopsy was evaluated in this study.

Methods

In this retrospective study, the data of patients with unclarified ILDs or PPLs who underwent TBLC guided by R-EBUS between April 2020 and December 2021 at Shanghai Pulmonary Hospital in China were analyzed.

Results

A total of 137 patients [72 men, 65 women; median age, 52 years (range, 24-76 years)] were enrolled in the study. Out of the 137 patients included in the study, 123 (89.8%) were diagnosed after multidisciplinary discussions (MDDs), including 105 (85.4%) with ILD, 10 (8.1%) with tuberculosis, and 8 (6.5%) with a malignant tumor. Sixty-five (47.4%) patients had a definitive pathologic diagnosis through TBLC, including 54 (83.1%) with ILD, 5 (7.7%) with tuberculosis and 6 (9.2%) with malignant tumors. The overall pathological diagnosis rate was 47.4%. In addition to clarifying the blood supply situation of the candidate target, R-EBUS detected lesions in 44 (32.1%) patients. Mild and moderate bleeding occurred in 75.2% and 24.8% of patients, respectively. No cases of severe bleeding were observed. Pneumothorax occurred in 6 (4.4%) patients, of which 2 recovered without additional treatment, and 4 (66.7%) needed closed thoracic drainage. Hydropneumothorax and mediastinal emphysema occurred in one patient each. No patients died due to TBLC.

Conclusions

R-EBUS-guided TBLC is safe and effective for the diagnosis of lung diseases, including ILDs and other PPLs. R-EBUS can guide cryobiopsy and avoid the potential risk of severe bleeding as well as radiation exposure. The pathological diagnosis rate of ILDs is relatively low, and MDD plays an important role in the diagnosis of ILDs.

Lung Involvement in Adult T-Cell Lymphoma Diagnosed Using Bronchoscopic Cryobiopsy: A Case Report and Review of the Literature

The diagnosis of pulmonary lymphoma using small tissue samples is difficult and often requires surgical procedures; thus, a less invasive sampling method is desirable. Moreover, pulmonary involvement in adult T-cell lymphoma (ATL) is often difficult to diagnose, especially in cases without characteristic flower cells. Here, we present the case of a 78-year-old man, in whom pathological examination of the transbronchial lung biopsy (TBLB) specimen did not reveal malignant findings; therefore, transbronchial lung cryobiopsy (TBLC) in combination with endobronchial ultrasonography (EBUS) was used to diagnose ATL based on the pathological findings. A literature review identified 18 cases of pulmonary lymphomas diagnosed using TBLC. Among the 19 cases, including our own, 16 cases were of B-cell lymphoma (84.2%), and the present case is the first case of ATL diagnosed using TBLC. Eighty percent of the cases underwent a biopsy (more than two samples) of the middle or lower lobe and were diagnosed without major complications. EBUS was used with TBLC in three cases to identify the location of the pulmonary lesions. In the present case, EBUS was also useful for avoiding vascular biopsy. Although large-scale prospective studies are required to establish precise guidelines for diagnosing pulmonary lymphomas using TBLC, our case report and review contributes to a deeper understanding of the diagnosis of rare diseases.

Clinical outcomes of transbronchial cryobiopsy using a 1.1-mm diameter cryoprobe for peripheral lung lesions - A prospective pilot study

OBJECTIVES

Transbronchial cryobiopsy (TBCB) is a novel technique for the diagnosis of peripheral lung lesions (PLLs). We aim to evaluate the clinical outcomes of TBCB using a new 1.1-mm diameter cryoprobe for the diagnosis of PLLs.

MATERIALS AND METHODS

We performed a prospective observational pilot study on the diagnosis of PLLs (diameter ≤30 mm) by TBCB, using a 1.1-mm diameter cryoprobe with radial endobronchial ultrasound (RP-EBUS), virtual bronchoscopic navigation and fluoroscopy from December 2021 to July 2022. Primary outcome was the pathological diagnostic yield of TBCB, and secondary outcome was adverse event.

RESULTS

A total of 50 patients were enrolled (mean lesion size, 21 mm). TBCB was performed in 49 patients up to three times except for the one with "invisible" finding on RP-EBUS. The overall diagnostic yield of TBCB was 90% (45/50). There was no difference in the diagnostic yield between size (20 mm vs. 20-30 mm; 88% [22/25] vs. 92% [23/25]; P = 1.000), RP-EBUS findings (concentric vs. others; 97% [28/29] vs. 81% [17/21]; P = 0.148), and acute angle location (apical segment of both upper lobes vs. others; 92% [12/13] vs. 89% [33/37]; P = 1.000). The cumulative diagnostic yields of the first, second, and third TBCB were 82% (41/50), 88% (44/50), and 90% (45/50), respectively. Mild bleeding was developed in 56% (28/50), and moderate bleeding was found in 26% (13/50).

CONCLUSION

TBCB using a 1.1-mm diameter cryoprobe is an effective, reasonable method for the diagnosis of PLLs regardless of its size, RP-EBUS finding, and anatomical location without serious complication.

TRIAL REGISTRATION

Clinical Trials.Gov (NCT05046093).

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions: A propensity score analysis

OBJECTIVES

Recently introduced cryobiopsy can provide quantitatively and qualitatively excellent specimens. However, few studies have directly compared the diagnostic yield of cryobiopsy for peripheral pulmonary lesions (PPLs) with that of conventional sampling methods.

MATERIAL AND METHODS

We retrospectively reviewed data from consecutive patients who underwent diagnostic bronchoscopy using radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs (October 2015 to September 2020). Patients who underwent cryobiopsy were assigned to the cryo group, whereas those who did not undergo cryobiopsy were assigned to the conventional group. The diagnostic outcomes of both groups were compared using propensity score analyses.

RESULTS

A total of 2,724 cases were identified, including 492 and 2,232 cases in the cryo and conventional groups, respectively. Propensity scoring was performed to match baseline characteristics, and 481 pairs of cases were selected for each matched group (m-group). The diagnostic yield was significantly higher in the m-cryo group than in the m-conventional group (89.2% vs. 77.6%, odds ratio [OR] = 2.36 [95% confidence interval [CI] = 1.65-3.38], P < 0.001). Propensity score stratification (OR = 2.35 [95% CI = 1.71-3.23]) and regression adjustment (OR = 2.54 [95% CI = 1.83-3.52]) also demonstrated the diagnostic advantages of cryobiopsy. The subgroup analysis revealed that cryobiopsy was notably effective for lesions in the middle lobe/lingula, right/left lower lobe, lesions with ground-glass opacity, and lesions invisible on chest radiography. Although there were more cases of grade 2 and 3 bleeding in the m-cryo group than in the m-conventional group (38.0% vs. 10.2% and 1.5% vs. 0.8%, respectively; P < 0.001), no grade 4 bleeding was observed.

CONCLUSION

The propensity score analyses revealed that cryobiopsy was associated with a higher diagnostic yield for PPLs than conventional sampling methods. However, increased bleeding risk should be noted as a potential complication.

An Innovative Method: Predicting the Visibility of Radial Endobronchial Ultrasound for Peripheral Pulmonary Nodules by Virtual Bronchoscopic Navigation

Background: The diagnosis of peripheral pulmonary nodules (PPNs) still is the key and difficult point. Previous studies have demonstrated that the diagnostic yield of radial endobronchial ultrasound (rEBUS) visible nodules is significantly higher than that of invisible nodules. The traditional method of predicting the rEBUS-visibility of nodules is based on the CT-bronchus signs, but its effectiveness may be unsatisfactory. Objective: We innovate a valuable predictive model based on virtual bronchoscopic navigation to identify beforehand which PPNs are likely to be successfully visualized by rEBUS. The innovative predictor is the ratio of the size of lesions (S) to the shortest straight-line distance (D) from the terminal point of the virtual navigation path to the localization point of the nodule. Methods: This is a retrospective study. On the training dataset of 214 patients, a receiver operating characteristic curve was drawn to understand the utility of the predictive model and get the optimal cut-off points. Ninety-two cases were enrolled in the validation dataset to validate the external predictive accuracy of the predictor. Results: The optimal cut-off point of the curve was 1.84 with the Youden index of 0.65, at which point the area under the curve was 0.85 (95% CI: 0.76-0.95). The predictor has a good performance in the validation dataset with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 81%, 100%, 100%, 71%, and 87%, respectively. Conclusion: The S/D ratio is a valuable and innovative method to identify beforehand which PPNs are likely to be successfully visualized by rEBUS. If the S/D ratio of the nodule is greater than 1.84, it will be visualized by rEBUS.

Applications of cryobiopsy in airway, pleural, and parenchymal disease

INTRODUCTION

:Cryobiopsy is a novel diagnostic technique for thoracic diseases which has been extensively investigated over the past 20 years. It was originally proposed for the diagnosis of endobronchial lesions and diffuse parenchymal lung disease due to limitations of conventional sampling techniques including small size and presence of artifacts.

AREAS COVERED

:We will review recent evidence related to the expanding use of cryobiopsy in thoracic diseases. To identify references, the MEDLINE database was searched from database inception until May 2022 for case series, cohort studies, randomized controlled trials, systematic reviews and meta-analyses related to cryobiopsy.

EXPERT OPINION

Cryobiopsy has expanding applications in the field of thoracic diseases. Evidence to support transbronchial cryobiopsy as an alternative to surgical lung biopsy is increasing and was recently endorsed as a conditional recommendation by the latest American Thoracic Society guideline update for Idiopathic Pulmonary Fibrosis. Developments in technology and technique, in particular the availability of a 1.1 mm flexible cryoprobe, have extended applications to pulmonary diseases, including diagnosis of interstitial lung diseases, peripheral pulmonary lesions, and lung transplant rejection.