Efficacy of Radial Endobronchial Ultrasound (R-EBUS) guided transbronchial cryobiopsy for peripheral pulmonary lesions (PPL...s): A systematic review and meta-analysis

Ultrathin bronchoscopy-guided small airway biopsy for diagnosing sarcoidosis: A prospective study

New ultrathin bronchoscopes (UTBs) enable the inspection and biopsy of small airways, potentially offering diagnostic advantages in sarcoidosis. In this prospective study, patients with suspected sarcoidosis underwent airway inspection with a UTB. Observed airway abnormalities were categorised into six predefined patterns. UTB-directed small airway biopsies (SABs) were collected from the upper lobes following a standardised procedure. We evaluated the prevalence and patterns of SAAs, as well as the diagnostic yield of UTB-directed SAB. Among 79 participants, 65 (82.3%) were diagnosed with sarcoidosis. Small airway abnormalities were identified in 26/65 (40%) patients, predominantly in those with parenchymal involvement on CT compared to those with lymphadenopathy only (58.1% VS. 23.5%, P = 0.005). The diagnostic yield of SABs for detecting granulomas was significantly higher in patients with SAAs than in those without (65.4% VS. 23.1%, P = 0.001) and in patients with parenchymal disease on CT compared to those without (54.8% VS. 26.5%, P = 0.02). Notably, random biopsies taken under direct visualisation from small airway carinas revealed peribronchiolar parenchyma in 23% of the patients. Small airway abnormalities are prevalent in sarcoidosis patients with parenchymal involvement, and biopsying these abnormalities yields a high rate of granuloma detection.

Diagnostic yield and safety of transbronchial lung cryobiopsy for diffuse parenchymal lung diseases diagnosis: Comparison between 1.7-mm and 1.9-mm probes

Purpose of the research: transbronchial lung cryobiopsy has been recently accepted as a valid and less invasive alternative to surgical lung biopsy. The purpose of this randomized controlled study was to evaluate, for the first time, the quality and safety of biopsy specimens obtained by using the new disposable 1.7-mm cryoprobe compared with the standard re-usable 1.9 mm cryoprobe in the diagnosis of diffuse parenchymal lung diseases. Methods: 60 consecutive patients were prospectively enrolled and randomly assigned to two different groups: 1.9 mm (group A) and 1.7 mm (group B); primary endpoints were pathological and multidisciplinary diagnostic yield, sample size and complication rate. Principal results: the pathological diagnostic yield of cryobiopsy was 100% in group A and 93.3% in group B (p = 0.718); cryobiopsy median diameter was 6.8 mm in group A and 6.7 mm in group B (p = 0,5241). Pneumothorax occurred in 9 patients in group A and 10 in group B (p = 0.951); mild-to-moderate bleeding in 7 cases and 9 cases in group A and B respectively (p = 0.559). No death or severe adverse events were observed. Conclusions: there was no statistically significant difference between the two groups, regarding diagnostic yield, adverse events and sampling adequacy.

Study protocol for a randomized trial comparing cryobiopsy and conventional biopsy for peripheral pulmonary lesions

BACKGROUND

The introduction of radial endobronchial ultrasound (R-EBUS) and navigation has improved the diagnostic yield of bronchoscopy for peripheral pulmonary lesions (PPLs). Cryobiopsy could further raise the yield, and the advent of single-use cryoprobes has shown promise in enhancing yields even when used alone. This multicenter randomized controlled trial aims to compare the diagnostic performance of cryobiopsy with that of conventional biopsy during bronchoscopy for PPLs.

METHODS

The study will enroll 660 patients with PPLs ≤30 mm. Eligible patients will undergo bronchoscopy with a thin bronchoscope and R-EBUS. If the target lesion is considered reachable based on R-EBUS findings, patients will be allocated equally to the conventional biopsy and cryobiopsy groups. Conventional biopsy will be performed using forceps and/or aspiration needles, whereas cryobiopsy will employ a single-use cryoprobe. The primary endpoint is to compare the histology-based diagnostic yield between the two groups. A subgroup analysis will also be conducted based on predetermined factors to explore the populations in which cryobiopsy is likely to be effective. The secondary endpoints are to evaluate differences in diagnostic value and safety characteristics between the two groups.

DISCUSSION

This will be the first study to evaluate the efficacy of cryobiopsy in diagnostic bronchoscopy for PPLs. The results of this study directly comparing cryobiopsy with conventional biopsy will elucidate differences in their diagnostic performance.

ETHICS AND DISSEMINATION

The National Cancer Center Institutional Review Board approved this study (No. 2022-123, approval date: October 24, 2022).

TRIAL REGISTRATION

The University Hospital Medical Information Network Clinical Trials Registry (UMIN000049329).

Cryoprobe biopsy versus mechanical biopsies in pulmonary diagnostics

PURPOSE OF REVIEW

Biopsy tools have been essential in improving the diagnostic accuracy of bronchoscopic procedures. Of these tools, cryobiopsy has emerged as a promising technique for diagnosing thoracic diseases. This review summarizes the existing data comparing cryobiopsies to other mechanical biopsy methods for sampling endobronchial, parenchymal, and mediastinal targets.

RECENT FINDINGS

Initially adopted for managing airway stenoses, the use of cryoprobes has expanded to diagnosing endobronchial lesions, parenchymal opacities, and mediastinal lymph node pathologies. Studies have demonstrated that cryobiopsy offers a higher diagnostic yield than forceps biopsy alone. By leveraging the Joule-Thomson effect to freeze and collect larger tissue samples compared to traditional methods, cryobiopsy improves diagnostic accuracy and helps in better characterizing the nature of the lesions. While the risk of complications, such as pneumothorax and hemorrhage are comparable to, or higher than traditional biopsy methods, cryobiopsy's enhanced diagnostic capabilities make it a valuable tool in the assessment of pulmonary disease.

SUMMARY

Compared with other mechanical biopsy techniques, cryoprobe biopsies significantly enhance the diagnostic yield for endobronchial lesions, interstitial lung disease, pulmonary nodules, and mediastinal lymph nodes.

Ultrasound-guided transbronchial cryobiopsy of mediastinal and hilar lesions: a multicenter pragmatic cohort study with real-world evidence

BACKGROUND

Limited data exist on the reliability, efficacy and safety of ultrasound-guided transbronchial cryobiopsy for suspicious mediastinal and hilar lesions. This study shares findings from implementing this method and compares the results with those of the standard endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA).

METHODS

Patients undergoing diagnostic bronchoscopy for mediastinal or hilar lesions in four Swiss centres were included. The study aims to assess the diagnostic yield and safety of EBUS-guided cryobiopsy compared with EBUS-TBNA. Tunnelling to the target lesion was performed using an electric needle knife (70.8%), a 19 G- (12.4%) or a 22 G needle (16.8%). Cryobiopsies were obtained with a freezing time of 4-7 s (18.2% with a 1.7 mm probe) or 6-10 s (81.8% with a 1.1 mm probe).

RESULTS

Altogether, 137 patients were enrolled with a median follow-up of 89 days. The overall diagnostic yield was 56.2% for EBUS-TBNA and 91.2% for cryobiopsies (p<0.001). Cryobiopsies increased the diagnostic yield for benign disorders (+28.5%), uncommon tumours (+5.9%) and other metastatic cancer (+0.6%), but not for lung cancer (+0%). For lung cancer (n=27), immunohistochemistry was obtainable in 40.7% of EBUS-TBNA (median of 3 probes [IQR 3 to 3]), significantly lower than cryobiopsy's 88.9% yield (median of 4 probes [IQR 3 to 5]) (p<0.001). Adverse events were found in 23.4% of participants; 10.2% had mild to moderate bleeding, 0.7% had pneumonia, and 0.7% (one) of patients had pneumothorax following pneumomediastinum. No deaths or mediastinum infections were observed.

CONCLUSION

Cryobiopsy of mediastinal and hilar lesions improves the diagnostic yield compared with EBUS-TBNA while maintaining a favourable safety profile.

Viability and diagnostic potential of tissues obtained through cryobiopsy

BACKGROUND

Transbronchial lung cryobiopsy is primarily used for diagnosing interstitial lung diseases and tumors, providing larger tissue samples with reduced tissue crushing than traditional biopsies. However, freezing during cryobiopsy may damage cells, potentially affecting diagnostic methods that require live cells, such as flow cytometry (FCM). We aimed to determine the extent of freezing-related cell damage in cryobiopsies using cells cultured in vitro.

METHODS

To investigate the relationship between freezing duration and sample volume, Jurkat cells underwent freezing for durations ranging from 2 to 6 s, with 1-s intervals, using either 1-mm- or 1.7-mm cryoprobes. FCM was conducted to assess both cell viability (2, 4, and 6 s) and cell-surface molecule expression (3 and 6 s) over varying freezing times. Additionally, we describe a clinical case involving a 70-year-old man suspected of malignant lymphoma, in which tissue samples were obtained via both forceps biopsy and cryobiopsy methods to compare the pathological and cytological features between the methods.

RESULTS

Harvested cell count increased with freezing duration, with a notable increase in viable cell percentage. Moreover, cells distant from the cryoprobe exhibited higher survival rates under milder freezing conditions. FCM revealed significantly higher marker expression levels in viable cryobiopsy samples than in non-viable samples. The clinical case demonstrated that cryobiopsy yields a significant proportion of live cells (>90%), with cytological findings consistent with those of non-frozen samples.

CONCLUSIONS

Cryobiopsy may be beneficial for histopathological diagnosis, providing sufficient viable cells for FCM, and can be used for diagnosing malignant lymphomas and other pulmonary conditions.

Pulmonary endoscopy - central to an interventional pulmonology program

INTRODUCTION

Pulmonary endoscopy occupies a central role in Interventional Pulmonology and is frequently the mainstay of diagnosis of respiratory disease, in particular lung malignancy. Older techniques such as rigid bronchoscopy maintain an important role in central airway obstruction. Renewed interest in the peripheral pulmonary nodule is driving major advances in technologies to increase the diagnostic accuracy and advance new potential endoscopic therapeutic options.

AREAS COVERED

This paper describes the role of pulmonary endoscopy, in particular ultrasound in the diagnosis and staging of lung malignancy. We will explore the recent expansion of ultrasound to include endoscopic ultrasound - bronchoscopy (EUS-B) and combined ultrasound (CUS) techniques. We will discuss in detail the advances in the workup of the peripheral pulmonary nodule.We performed a non-systematic, narrative review of the literature to summarize the evidence regarding the indications, diagnostic yield, and safety of current bronchoscopic sampling techniques.

EXPERT OPINION

EBUS/EUS-B has revolutionized the diagnosis and staging of thoracic malignancy resulting in more accurate assessment of the mediastinum compared to mediastinoscopy alone, thus reducing the rate of futile thoracotomies. Although major advances in the assessment of the peripheral pulmonary nodule have been made, the role of endoscopy in this area requires further clarification and investigation.

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.

EBUS-guided cryobiopsy in the diagnosis of thoracic disorders

BACKGROUND

Endobronchial Ultrasound (EBUS) has emerged as a crucial tool for diagnosing intrathoracic disorders, particularly in the staging of lung cancer. However, its diagnostic capabilities in the context of benign and rare diseases remain a subject of debate.

AIM

to investigate the diagnostic yield and safety of EBUS-transbronchial mediastinal cryobiopsy (EBUS-TMC) in comparison to EBUS-transbronchial needle aspiration (TBNA) for a broad spectrum of intrathoracic diseases.

METHODS

a single-centre retrospective observational study conducted on 48 patients who underwent both EBUS-TBNA and endobronchial ultrasound-transbronchial mediastinal cryobiopsy (EBUS-TMC) in the same procedure between August 2021 and October 2023.

RESULTS

The overall diagnostic yield of EBUS-TMC surpassed that of EBUS-TBNA (95.8% vs 54.1 %), notably excelling in the diagnosis of sarcoidosis (92.8% vs 78.5 %), rare mediastinal disorders (100% vs 0 %), hyperplastic lymphadenopathy (100% vs 0 %), and lymphoproliferative disease (100% vs 0 %). No significant differences were observed in the diagnosis of NSCLC and SCLC. Samples obtained through EBUS-TMC facilitated the acquisition of NGS and immunohistochemical analyses more readily.

CONCLUSION

EBUS-TMC may contribute to the precise diagnosis and subtyping of mediastinal diseases, especially lymphomas and rare mediastinal tumors, thereby reducing the number of non-diagnostic procedures.

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.

A pilot study of optical coherence tomography-guided transbronchial biopsy in peripheral pulmonary lesions

BACKGROUND

The diagnosis of peripheral pulmonary lesions (PPLs) remains challenging. Despite advancements in guided transbronchial biopsy (TBB) techniques, diagnostic yields haven't reached ideal levels. Optical coherence tomography (OCT) has been developed for application in pulmonary diseases, yet no data existed evaluating effectiveness in diagnosing PPLs.

RESEARCH DESIGN AND METHODS

This study included patients who underwent OCT and radial endobronchial ultrasound (R-EBUS)-guided TBB. OCT and R-EBUS imaging features were analyzed to differentiate between benign and malignant PPLs and subtypes of lung cancer.

RESULTS

A total of 89 patients were included in this study. The diagnostic yield of OCT-guided TBB stood at 56.18%, R-EBUS-guided TBB was 83.15% (P<0.01). The accuracy of OCT to judge the nature of lesions was 92.59%, while R-EBUS was 77.92%. The accuracy of OCT in predicting squamous carcinoma (SCC) and adenocarcinoma were both 91.30%.

CONCLUSIONS

Although the diagnostic yield of OCT-guided TBB fell short of that achieved by R-EBUS, OCT possessed the capability to judge the nature of lesions and guide the pathological classification of malignant lesions. Further extensive prospective studies are necessary to thoroughly assess the characteristics of this procedure.

CLINICAL TRIAL REGISTRATION

https://register.clinicaltrials.gov/ identifier is NCT06419114.

Comparison of cryobiopsy and forceps biopsy for the diagnosis of mediastinal lesions: A randomised clinical trial

INTRODUCTION

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the standard approach for lung cancer staging. However, its diagnostic utility for other mediastinal diseases might be hampered by the limited tissue retrieved. Recent evidence suggests the novel sampling strategies of forceps biopsy and cryobiopsy as auxiliary techniques to EBUS-TBNA, considering their capacity for larger diagnostic samples.

METHODS

This study determined the added value of forceps biopsy and cryobiopsy for the diagnosis of mediastinal diseases. Consecutive patients with mediastinal lesions of 1 cm or more in the short axis were enrolled. Following completion of needle aspiration, three forceps biopsies and one cryobiopsy were performed in a randomised pattern. Primary endpoints included diagnostic yield defined as the percentage of patients for whom mediastinal biopsy led to a definite diagnosis, and procedure-related complications.

RESULTS

In total, 155 patients were recruited and randomly assigned. Supplementing EBUS-TBNA with either forceps biopsy or cryobiopsy increased diagnostic yield, with no significant difference between EBUS-TBNA plus forceps biopsy and EBUS-TBNA plus cryobiopsy (85.7 % versus 91.6 %, P = 0.106). Yet, samples obtained by additional cryobiopsies were more qualified for lung cancer molecular testing than those from forceps biopsies (100.0 % versus 89.5 %, P = 0.036). When compared directly, the overall diagnostic yield of cryobiopsy was superior to forceps biopsy (85.7 % versus 70.8 %, P = 0.001). Cryobiopsies produced greater samples in shorter procedural time than forceps biopsies. Two (1.3 %) cases of postprocedural pneumothorax were detected.

CONCLUSIONS

Transbronchial mediastinal cryobiopsy might be a promising complementary tool to supplement traditional needle biopsy for increased diagnostic yield and tissue harvesting.

TRIAL REGISTRATION

ChiCTR2000030373.

An explorative analysis on the optimal cryo-passes and freezing time of the ultrathin cryoprobe in endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy

EBUS-guided transbronchial mediastinal cryobiopsy (TBMC) has emerged as a promising biopsy tool for diagnosing hilar and mediastinal pathologies. However, several fundamental technical aspects of TBMC remain unexplored. This study aims to determine the optimal number of cryo-passes and freezing time of the ultrathin cryoprobe in EBUS-TBMC concerning specimen size and procedural diagnostic yield. We conducted a retrospective chart review of patients with mediastinal and hilar lesions who underwent EBUS-TBMC between January 2021 and April 2023 across three hospitals in Malaysia. A total of 129 EBUS-TBMC procedures were successfully completed, achieving an overall diagnostic yield of 88.4%. Conclusive TBMC procedures were associated with larger specimen sizes (7.0 vs. 5.0 mm, p < 0.01). Specimen size demonstrated a positive correlation with diagnostic yield (p < 0.01), plateauing at specimen size of 4.1-6.0 mm. A significant positive correlation was also observed between the number of cryo-passes and both specimen size (p < 0.01) and diagnostic yield (p < 0.05). Diagnostic yield plateaued after 2-3 cryo-passes. In contrast, longer freezing times trended towards smaller specimens and lower diagnostic yield, though not reaching statistical significance. The highest diagnostic yield was recorded at the 3.1-4.0 s freezing time. The safety profile of TBMC remains favourable, with one case (0.8%) of pneumothorax and nine cases (7%) of self-limiting bleeding. In our cohort, TBMC performance with 2-3 cryo-passes and a 3.1-4.0 s freezing time to achieve a total aggregate specimen size of 4.1-6.0 mm appeared optimal. Further prospective studies are needed to validate these findings.

Improving diagnostic strategies in bronchoscopy for peripheral pulmonary lesions

INTRODUCTION

In the past two decades, bronchoscopy of peripheral pulmonary lesions (PPLs) has improved its diagnostic yield due to the combination of various instruments and devices. Meanwhile, the application is complex and intertwined.

AREAS COVERED

This review article outlines strategies in diagnostic bronchoscopy for PPLs. We summarize the utility and evidence of key instruments and devices based on the results of clinical trials. Future perspectives of bronchoscopy for PPLs are also discussed.

EXPERT OPINION

The accuracy of reaching PPLs by bronchoscopy has improved significantly with the introduction of combined instruments such as navigation, radial endobronchial ultrasound, digital tomosynthesis, and cone-beam computed tomography. It has been accelerated with the advent of approach tools such as newer ultrathin bronchoscopes and robotic-assisted bronchoscopy. In addition, needle aspiration and cryobiopsy provide further diagnostic opportunities beyond forceps biopsy. Rapid on-site evaluation may also play an important role in decision making during the procedures. As a result, the diagnostic yield of bronchoscopy for PPLs has improved to a level comparable to that of transthoracic needle biopsy. The techniques and technologies developed in the diagnosis will be carried over to the next step in the transbronchial treatment of PPLs in the future.

Radial endobronchial ultrasound - guided bronchoscopy for the diagnosis of peripheral pulmonary lesions: A systematic review and meta-analysis of prospective trials

Background

The diagnostic yield of radial endobronchial ultrasound (r-EBUS) for the diagnosis of peripheral pulmonary lesions (PPLs) varies between studies and is affected by multiple factors. We aimed to evaluate the efficacy and safety of r-EBUS, and to explore the factors influencing the diagnostic yield of r-EBUS in patients with PPLs.

Methods

The PubMed, Web of Science, and EMBASE databases were searched to identify relevant studies that used r-EBUS for diagnosing PPLs from the date of inception to Dec 2022. Meta-analysis was conducted using Review Manager 5.4 and Stata 15.1.

Results

An analysis of 46 studies with a total of 7252 PPLs was performed. The pooled diagnostic yield of r-EBUS was 73.4 % (95 % CI: 69.9%-76.7 %), with significant heterogeneity detected among studies (I2 = 90 %, P < 0.001). Further analysis demonstrated PPLs located in the middle or lower lobe, >2 cm in size, malignant in type, solid in appearance on computerized tomography (CT), present in bronchus sign, the within probe location, and the addition of rapid on-site evaluation (ROSE) were associated with increased diagnostic yield, whereas use of a guide sheath (GS), bronchoscopy type, and a multimodality approach failed to influence the outcome. The pooled incidence rates of overall complications, pneumothorax and moderate and severe bleeding were 3.1 % (95 % CI: 2.1%-4.3 %), 0.4 % (95 % CI: 0.1%-0.7 %) and 1.1 % (95 % CI: 0.5%-2.0 %), respectively.

Conclusions

r-EBUS has an appreciable diagnostic yield and an excellent safety manifestation when used to deal with PPLs.

Transbronchial Cryobiopsy Using the Ultrathin 1.1-mm Cryoprobe with Ultrathin Bronchoscopy under Radial Endobronchial Ultrasound Guidance for Diagnosis of Peripheral Pulmonary Lesions

INTRODUCTION

Today, the increasing number of incidentally detected peripheral pulmonary lesions (PPLs) within and outside lung cancer screening trials is a diagnostic challenge. This fact encourages further improvement of diagnostic procedures to increase the diagnostic yield of transbronchial biopsy, which has been shown to have a low complication rate. The purpose of this study was to evaluate the safety and feasibility of a new ultrathin 1.1 cryoprobe that can be placed through an ultrathin bronchoscope (UTB) using fluoroscopy and radial endobronchial ultrasonography (rEBUS) navigation for assessing PPLs.

METHODS

Thirty-five patients with PPL less than 4 cm in diameter were prospectively enrolled to receive transbronchial cryobiopsies (TBCBs) using the ultrathin 1.1-mm cryoprobe. Navigation to the PPL was accomplished with the UTB. Under rEBUS and fluoroscopy guidance up to 4 cryobiopsies were obtained. The sample sizes of the biopsies were compared to a historic collective derived from a 1.9-mm cryoprobe and standard forceps. The feasibility and safety of the procedure, the cumulative and overall diagnostic yield, and the cryobiopsy sizes were evaluated.

RESULTS

After detection with the rEBUS, TBCB was collected from 35 PPLs, establishing a diagnosis in 25 cases, corresponding to an overall diagnostic yield of 71.4%. There was no difference in diagnostic yield for PPL <20 mm or ≥20 mm. All cryobiopsies were representative with a mean tissue area of 11.9 ± 4.3 mm2, which was significantly larger compared to the historic collective (p = 0.003). Six mild and four moderate bleeding events and 1 case of pneumothorax were observed.

CONCLUSIONS

Using the ultrathin 1.1-mm cryoprobe combined with an UTB for rEBUS-guided TBCB of PPL is feasible and safe. This diagnostic approach improves bronchoscopic techniques for diagnosing peripheral lung lesions and may contribute to improve diagnosis of lung cancer even in small PPL.

Using cryoprobes of different sizes combined with cone-beam computed tomography-derived augmented fluoroscopy and endobronchial ultrasound to diagnose peripheral pulmonary lesions: a propensity-matched study

BACKGROUND

Endobronchial ultrasound (EBUS) and cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) are utilized for the diagnosis of peripheral pulmonary lesions (PPLs). Combining them with transbronchial cryobiopsy (TBC) can provide sufficient tissue for genetic analysis. However, cryoprobes of different sizes have varying degrees of flexibility, which can affect their ability to access the target bronchus and potentially impact the accuracy. The aim of this study was to compare the diagnostic efficacy of cryoprobes of varying sizes in CBCT-AF and EBUS for the diagnosis of PPLs.

METHODS

Patients who underwent endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) and TBC combined with CBCT-AF for PPLs diagnosis between January 2021 and May 2022 were included. Propensity score matching and competing-risks regression were utilized for data analysis. Primary outcome was the diagnostic accuracy of TBC.

RESULTS

A total of 284 patients underwent TBC, with 172 using a 1.7-mm cryoprobe (1.7 group) and 112 using a 1.1-mm cryoprobe (1.1 group). Finally, we included 99 paired patients following propensity score matching. The diagnostic accuracy of TBC was higher in the 1.1 group (80.8% vs. 69.7%, P = 0.050), with a similar rate of complications. Subgroup analysis also revealed that the 1.1 group had better accuracy when PPLs were located in the upper lobe (85.2% vs. 66.1%, P = 0.020), when PPLs were smaller than 20 mm (78.8% vs. 48.8%, P = 0.008), and when intra-procedural CBCT was needed to be used (79.5% vs. 42.3%, P = 0.001). TBC obtained larger specimens than TBB in both groups. There is still a trend of larger sample size obtained in the 1.7 group, but there is no statistically different between our two study groups (40.8 mm2 vs. 22.0 mm2, P = 0.283).

CONCLUSIONS

The combination of TBC with CBCT-AF and EBUS is effective in diagnosing PPLs, and a thin cryoprobe is preferred when the PPLs located in difficult areas.

Diagnostic Value of Transbronchial Lung Cryobiopsy Using an Ultrathin Cryoprobe and Guide Sheath for Peripheral Pulmonary Lesions

BACKGROUND

The addition of cryobiopsy to conventional biopsy methods improves the diagnostic yield of peripheral pulmonary lesions. Moreover, cryobiopsy with a guide sheath (GS) provides additional diagnostic benefits. Semi-real-time biopsy can be repeatedly performed using conventional biopsy devices and a GS, and subsequent cryobiopsy can be easily performed at the same location. Recently, a disposable 1.1 mm-diameter ultrathin cryoprobe has been developed and can be used with a 1.95 mm GS in a 2.0 mm working channel. In this study, we evaluated the diagnostic performance of transbronchial lung cryobiopsy (TBLC) with the 1.1 mm cryoprobe and a GS in patients with peripheral pulmonary lesions.

METHODS

We retrospectively reviewed the medical records of patients who underwent endobronchial ultrasound transbronchial lung biopsy with a guide sheath and TBLC from July 23, 2021 to April 30, 2022 at Chungnam National University Hospital.

RESULTS

Of a consecutive series of 229 patients, 199 were included. The diagnostic yields of forceps biopsy and cryobiopsy were 65.3% (130/199) and 84.4% (168/199), respectively, and the total diagnostic yield was 91.5% (182/199) ( P <0.001 vs. forceps biopsy). Multivariate analysis showed that solid lesion morphology [adjusted odds ratio (OR) 3.659, P =0.002] was associated with a significantly greater diagnostic yield of cryobiopsy, whereas a lesion diameter >20 mm ( P =0.026; adjusted OR 3.816) and 'within' orientation ( P =0.004; adjusted OR 6.174) were associated with a significantly greater overall diagnostic yield.

CONCLUSION

TBLC using an ultrathin cryoprobe and GS markedly improves the diagnostic yield.

[Navigational bronchoscopy with tranbronchial cryobiopsy in differential diagnosis of peripheral pulmonary lesions]

OBJECTIVE

To evaluate the efficacy and safety of tranbronchial cryobiopsy (TBCB) with 1.9-mm and 1.1-mm cryoprobes in patients with peripheral pulmonary lesions (PPLs).

MATERIAL AND METHODS

We analyzed 34 patients (mean age 60 years) with PPLs who underwent bronchoscopy with TBCB. Mean lesion size was 31.5 mm, upper lobe localization was predominant (47% of cases). CT signs of appropriate bronchus were identified in 79% (27/34) of cases. Manual branch tracking and virtual bronchoscopy (VB) were performed pre-procedurally, and radial endobronchial ultrasonography (rEBUS) was performed during bronchoscopy for accurate positioning of PPLs. TBCB was performed using 1.9-mm (n=19) or 1.1-mm (n=15) cryoprobes without fluoroscopic guidance. Incidence and severity of bleeding and pneumothorax were evaluated in all patients.

RESULTS

Total efficacy of TBCB was 76.5% (26/34): 78.9% (15/19) for 1.9-mm cryoprobe and 73.3% (11/15) for 1.1-mm cryoprobe (p=0.702). Efficacy depended on the presence of CT signs of bronchus (presence - 94%, absence 14.3%, p<0.001) and PPL size (94% for PPL >30 mm and 58.8% for PPL <30 mm, p=0.016). Central probe position during rEBUS was associated with 94.7% diagnostic efficacy (18/19), adjacent probe position - 72.7% (8/11) (p=0.088). Bleeding grade 3 (Nasville) occurred in 5.8% (2/34) of cases, and no pneumothorax was observed.

CONCLUSION

TBCB is an effective and safe diagnostic method for PPLs.

Ultrasound in the Study of Thoracic Diseases: Innovative Aspects

Thoracic ultrasound (TU) has rapidly gained popularity over the past 10 years. This is in part because ultrasound equipment is available in many settings, more training programmes are educating trainees in this technique, and ultrasound can be done rapidly without exposure to radiation. The aim of this review is to present the most interesting and innovative aspects of the use of TU in the study of thoracic diseases. In pleural diseases, TU has been a real revolution. It helps to differentiate between different types of pleural effusions, guides the performance of pleural biopsies when necessary and is more cost-effective under these conditions, and assists in the decision to remove thoracic drainage after talc pleurodesis. With the advent of COVID19, the use of TU has increased for the study of lung involvement. Nowadays it helps in the diagnosis of pneumonias, tumours and interstitial diseases, and its use is becoming more and more widespread in the Pneumology ward. In recent years, TU guided biopsies have been shown to be highly cost-effective, with other advantages such as the absence of radiation and the possibility of being performed at bedside. The use of contrast in ultrasound to increase the cost-effectiveness of these biopsies is very promising. In the study of the mediastinum and peripheral pulmonary nodules, the introduction of echobronchoscopy has brought about a radical change. It is a fully established technique in the study of lung cancer patients. The introduction of elastography may help to further improve its cost-effectiveness. In critically-ill patients, diaphragmatic ultrasound helps in the assessment of withdrawal of mechanical ventilation, and is now an indispensable tool in the management of these patients. In neuromuscular patients, ultrasound is a good predictor of impaired lung function. Currently, in Neuromuscular Disease Units, TU is an indispensable tool. Ultrasound study of the intercostal musculature is also effective in the study of respiratory function, and is widely used in Respiratory Rehabilitation. In Intermediate Care Units, thoracic ultrasound is indispensable for patient management. In these units there are ultrasound protocols for the management of patients with acute dyspnoea that have proven to be very effective.

Is the diagnostic yield of mediastinal lymph node cryobiopsy (cryoEBUS) better for diagnosing mediastinal node involvement compared to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)? A systematic review

INTRODUCTION

New tools such as cryobiopsy of mediastinal lymph nodes (cryoEBUS) have been described to improve the diagnostic usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The literature suggests that this novel procedure could be associated with greater diagnostic usefulness than conventional EBUS-TBNA.

METHODS

To develop a systematic analysis and meta-analysis on the diagnostic diagnostic yield and safety of cryobiopsy of hilar and mediastinal adenopathies compared to EBUS-TBNA.

RESULTS

Seven studies that had included a total of 555 patients were considered in this review, with 365 (65.7%) of these patients having an etiology of malignant lymph node involvement. The overall diagnostic usefulness of cryoEBUS was higher compared to EBUS-TBNA (92% vs. 80%). However, when the results were analysed according to the specific aetiologies of the adenopathies, cryoEBUS was especially useful in cases of lymphomas or non-pulmonary carcinomas (83% vs. 42%) and in cases that were benign (87% vs. 60.1%), with no significant differences being found in specific cases of lung cancer. For lymphoma, cryoEBUS was diagnostic in 87% of cases compared to 12% for EBUS-TBNA and in addition, also allowed the characterisation of every lymphoma subtype. Genetic studies and immunohistochemical determination of PD-L1 was possible in almost all (97%) of the samples obtained by cryoEBUS, while this was only possible in 79% of those obtained by EBUS-TBNA. The most frequent complication was light bleeding, which was described in up to 85% of cases in some series.

CONCLUSION

CryoEBUS could represent a promising technique in the diagnostic algorithm used for mediastinal and hilar involvement. Although cryoEBUS did not significantly improve the diagnosis of lung cancer compared to EBUS-TBNA, the results were significantly better in patients with benign pathologies and other tumour types, including lymphomas. In addition, it seems that the samples obtained by cryoEBUS better defined the histological subtypes of lymphoma and allowed complete molecular characterisation in cases of lung cancer. The technique has proven to be safe and no serious complications were described after the procedure.

[Advanced bronchoscopic techniques for the diagnosis of peripheral lung nodule]

The endoscopic diagnosis of peripheral lung nodules is a challenging aspect of oncological practice. More often than not inaccessible by traditional endoscopy, these nodules necessitate multiple imagery tests, as well as diagnostic surgery for benign lesions. Even though transthoracic ultrasonography has a high diagnostic yield, a sizeable complication rate renders it suboptimal. Over recent years, a number of safe and accurate navigational bronchoscopic procedures have been developed. In this first part, we provide an overview of the bronchoscopic techniques currently applied for the excision and diagnostic analysis of peripheral lung nodules; emphasis is laid on electromagnetic navigation bronchoscopy and the association of virtual bronchoscopy planner with radial endobronchial ultrasound. We conclude by considering recent innovations, notably robotic bronchoscopy.

Radial Endobronchial Ultrasound-guided Transbronchial Cryobiopsy versus Forceps Biopsy for the Diagnosis of Solitary Pulmonary Nodules: A Prospective Randomised Trial

Background

Improvements in pulmonary diagnostic imaging and the development of lung cancer screening are increasing the prevalence of Solitary pulmonary nodules (SPNs). Fluoroscopically guided radial endobronchial ultrasound (EBUS) with transbronchial forceps biopsy (TB-FB) has been the conventional diagnostic method. Transbronchial cryobiopsy (TB-CB) is an alternative biopsy method. We sought to compare transbronchial cryobiopsy to transbronchial forceps biopsy for the diagnosis of SPNs.

Methods

A prospective, single-centre, randomised controlled trial was conducted at the Royal Adelaide Hospital (RAH). Patients with SPNs were randomised to either 5 transbronchial forceps biopsies or one transbronchial cryobiopsy. Complete blinding of investigators and participants was not possible, as transbronchial cryobiopsy required general anaesthesia. The primary outcome was diagnostic yield with secondary outcomes of specimen size, diagnostic yield for subsets challenging to access with forceps and safety.

Results

The overall diagnostic yield for the 28 enrolled subjects was 76.8%(22/28). The diagnostic yield was 91.7% (11/12 patients) for transbronchial cryobiopsy and 68.8% (11/16 patients) for forceps biopsy (p=0.14). Median biopsy sizes were consistently larger for the cryobiopsy arm at 7.0mm compared to 2.5mm(p<0.0001). An eccentric EBUS image signalling the probe was adjacent to the nodule occurred in 4/28 cases, and TB-CB confirmed a diagnosis in 3/3 randomised to this arm. There were no major complications with either technique.

Conclusion

Transbronchial cryobiopsy under the guidance of fluoroscopy and radial EBUS facilitates larger biopsy specimens without a significant increase in major complications. Further research is required to confirm the effect on diagnostic yield; however, our study supports a role for TB-CB in the diagnosis of SPNs and small, nodule-adjacent biopsies.

Clinical Trial Registration Number

Reference number of R20160213(HREC/16/RAH/37).

Predictive value of the resistance of the probe to pass through the lesion in the diagnosis of peripheral pulmonary lesions using radial probe endobronchial ultrasound with a guide sheath

Background

Transbronchial lung biopsy guided by radial probe endobronchial ultrasonography with a guide sheath (EBUS-GS-TBLB) is becoming a significant approach for diagnosing peripheral pulmonary lesions (PPLs). We aimed to explore the clinical value of the resistance of the probe to pass through the lesion in the diagnosis of PPLs when performing EBUS-GS-TBLB, and to determine the optimum number of EBUS-GS-TBLB.

Methods

We performed a prospective, single-center study of 126 consecutive patients who underwent EBUS-GS-TBLB for solid and positive-bronchus-sign PPLs where the probe was located within the lesion from September 2019 to May 2022. The classification of probe resistance for each lesion was carried out by two bronchoscopists independently, and the final result depended on the bronchoscopist responsible for the procedures. The primary endpoint was the diagnostic yield according with the resistance pattern. The secondary endpoints were the optimum number of EBUS-GS-TBLB and factors affecting diagnostic yield. Procedural complications were also recorded.

Results

The total diagnostic yield of EBUS-GS-TBLB was 77.8%, including 83.8% malignant and 67.4% benign diseases (P=0.033). Probe resistance type II displayed the highest diagnostic yield (87.5%), followed by type III (81.0%) and type I (61.1%). A significant difference between the diagnostic yield of malignant and benign diseases was detected in type II (P = 0.008), whereas others did not. Although most of the malignant PPLs with a definitive diagnosis using EBUS-GS-TBLB in type II or type III could be diagnosed in the first biopsy, the fourth biopsy contributed the most sufficient biopsy samples. In contrast, considerably limited tissue specimens could be obtained for each biopsy in type I. The inter-observer agreement of the two blinded bronchoscopists for the classification of probe resistance was excellent (κ = 0.84).

Conclusion

The probe resistance is a useful predictive factor for successful EBUS-GS-TBLB diagnosis of solid and positive-bronchus-sign PPLs where the probe was located within the lesion. Four serial biopsies are appropriate for both probe resistance type II and type III, and additional diagnostic procedures are needed for type I.

Robotic bronchoscopic needle-based confocal laser endomicroscopy to diagnose peripheral lung nodules

BACKGROUND AND OBJECTIVE

Robotic bronchoscopy has demonstrated high navigational success in small peripheral lung nodules but the diagnostic yield is discrepantly lower. Needle based confocal laser endomicroscopy (nCLE) enables real-time microscopic imaging at the needle tip. We aim to assess feasibility, safety and needle repositioning based on real-time nCLE-guidance during robotic bronchoscopy in small peripheral lung nodules.

METHODS

Patients with suspected peripheral lung cancer underwent fluoroscopy and radial EBUS assisted robotic bronchoscopy. After radial EBUS nodule identification, nCLE-imaging of the target area was performed. nCLE-malignancy and airway/lung parenchyma criteria were used to identify the optimal sampling location. In case airway was visualized, repositioning of the biopsy needle was performed. After nCLE tool-in-nodule confirmation, needle passes and biopsies were performed at the same location.

MEASUREMENTS AND MAIN RESULTS

Twenty patients were included (final diagnosis n = 17 (lung) cancer) with a median lung nodule size of 14.5 mm (range 8-28 mm). No complications occurred. In 19/20 patients, good quality nCLE-videos were obtained. In 9 patients (45%), real-time nCLE-imaging revealed inadequate positioning of the needle and repositioning was performed. After repositioning, nCLE-imaging provided tool-in-nodule-confirmation in 19/20 patients. Subsequent ROSE demonstrated representative material in 9/20 patients (45%) and overall diagnostic yield was 80% (16/20). Of the three patients with malignant nCLE-imaging but inadequate pathology, two were diagnosed with malignancy during follow-up.

CONCLUSION

Robotic bronchoscopic nCLE-imaging is feasible and safe. nCLE-imaging in small, difficult-to-access lung nodules provided additional real-time feedback on the correct needle positioning with the potential to optimize the sampling location and diagnostic yield.

Using cryobiopsy with Radial EBUS in high-bleeding-risk, peripheral pulmonary lesions (PPL): description of cases and technique

Cryobiopsy is an emerging tool in the diagnosis of peripheral pulmonary lesions (PPL) and becoming an important tool in the toolbox. Anecdotally the data on cryobiopsy use in the lung was extrapolated from the use of transbronchial cryobiopsy (TBCB) in Interstitial Lung disease (ILD). Similar to ILD data, cryobiopsy in PPL also provided larger tissue compared to forceps biopsies. Yet, unlike TBCB in ILD, the safety profile for cryobiopsy in PPL seems much more favourable, yet the number of publications on cryobiopsy in PPL remains sparse. Some PPL, both malignant and non-malignant are considered to be of a high bleeding risk due to vascularity of the tumour and/or inflammation of the blood vessels and surrounding tissue. The use of cryobiopsy and the risk of bleeding in this type of PPL have not been described. This paper describes four patients with PPL, undergoing cryobiopsy with radial EBUS for suspected lung cancer, and later diagnosed to have a PPL, deemed to be of a high bleeding risk. The use of cryobiopsy with radial ultrasonic examination for the vasculature of the PPL, bronchial blocker use, and airway protection as well as an expert team preserved the safety of the procedure.

The Additive Impact of Transbronchial Cryobiopsy Using a 1.1-mm Diameter Cryoprobe on Conventional Biopsy for Peripheral Lung Nodules

PURPOSE

The diagnostic yield of transbronchial biopsy (TBB) using radial probe endobronchial ultrasound (RP-EBUS) is 71%, which is lower than that of transthoracic needle biopsy. We investigated the performance and safety of sequential transbronchial cryobiopsy (TBC) using a novel 1.1-mm diameter cryoprobe, after conventional TBB using RP-EBUS for the diagnosis of peripheral lung lesions (PLLs).

Materials and Methods

From April 2021 to November 2021, 110 patients who underwent bronchoscopy using RP-EBUS for the diagnosis of PLL ≤ 30 mm were retrospectively included in our study. All records were followed until June 2022.

RESULTS

The overall diagnostic yield of combined TBB and TBC was 79.1%, which was higher than 60.9% of TBB alone (p=0.005). The diagnostic yield of sequential TBC was 65.5%, which increased the overall diagnostic yield by 18.2%. The surface area of tissues by TBC (mean area, 18.5 mm2) was significantly larger than those of TBB by 1.5-mm forceps (3.4 mm2, p < 0.001) and 1.9-mm forceps (3.7 mm2, p=0.011). In the multivariate analysis, PLLs with the longest diameter of ≤ 22 mm were found to be related to additional diagnostic benefits from sequential TBC (odds ratio, 3.51; 95% confidence interval, 1.043 to 11.775; p=0.042). Complications were found in 10.5% of the patients: pneumothorax (1.0%), infection (1.0%), and significant bleeding (8.6%). None of the patients developed any life-threatening complications.

CONCLUSION

Sequential TBC with a 1.1-mm cryoprobe improved the performance of conventional TBB using RP-EBUS without serious complications.

Use of the 1.1 mm cryoprobe through the radial EBUS GS (without the need for a bronchial blocker) to obtain samples safely in diagnosing PPL

Cryobiopsy for peripheral pulmonary lesions suspected of lung cancer is gaining popularity due to the larger non‐crushed samples capable of an array of molecular testing. However, the method of performing this procedure so far had been resource‐intensive and time‐consuming limiting the procedure to tertiary centres. Having to remove the cryobiopsy en masse with the bronchoscope was the main issue that hindered the safety of the procedure. We report two cases where the 1.1 mm cryoprobe was used and the cryobiopsy was extracted through the Radial EBUS GS whilst the bronchoscope remained in the bronchial tree, with excellent control of bleeding, due to the tamponading of the GS as well as the ability to attend to bleeding as soon as it occurred, due to the bronchoscope being inside the airway. This method of obtaining the cryobiopsy through the GS and keeping the bronchoscope in the airway improved the safety of cryobiopsy for PPL. Further studies are required to assess the consistency of yield and safety of this method.

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.

Ultrathin bronchoscopic cryobiopsy of peripheral pulmonary lesions

BACKGROUND AND OBJECTIVE

Ultrathin bronchoscopy aids in the diagnosis of peripheral pulmonary lesions. However, both the working channel and the specimens are small. A 1.1-mm ultrathin cryoprobe that can enter the working channel of the ultrathin bronchoscope is now available, which may overcome the limitations of small specimen size. The aim of this study was to evaluate the feasibility, efficacy and safety of ultrathin bronchoscopic cryobiopsy using an ultrathin cryoprobe for diagnosing peripheral pulmonary lesions.

METHODS

Patients with peripheral pulmonary lesions ≤30 mm in diameter were prospectively enrolled in the study. All patients underwent forceps biopsy followed by cryobiopsy using a 3.0-mm ultrathin bronchoscope under radial probe endobronchial ultrasound guidance, virtual bronchoscopic navigation and fluoroscopic guidance. The primary endpoint was the feasibility of cryobiopsy.

RESULTS

In total, 50 patients with peripheral pulmonary lesions were enrolled in the study; the median longest diameter on computed tomography was 17.9 mm. Cryobiopsy was performed successfully in 49 patients (98%). Forceps biopsy, cryobiopsy and the combination of these two methods provided a specific diagnosis in 54% (27/50), 62% (31/50) and 74% (37/50) of patients, respectively. The median size of specimens obtained via cryobiopsy was significantly larger than the median size obtained via forceps biopsy (7.0 vs. 1.3 mm² , respectively, p < 0.001). Mild bleeding during cryobiopsy occurred in 47 patients (94%). No moderate/severe bleeding or pneumothorax occurred.

CONCLUSION

Ultrathin bronchoscopic cryobiopsy is feasible, effective and sufficiently safe for the diagnosis of peripheral pulmonary lesions.

Efficacy of combined transbronchial lung cryobiopsy and conventional forceps biopsy for lung malignancies: a prospective cohort study

There are few prospective reports of transbronchial lung cryobiopsy (TBLC) for malignant tumors in combination with forceps biopsy. We investigated the clinical parameters in which TBLC is superior to forceps biopsy. This is a prospective cohort study to analyse the efficacy of TBLC for suspected malignancy. TBLC was performed after brushing cytology and forceps biopsy, and the diagnostic yield for TBLC, brushing cytology, and forceps biopsy were examined. Adverse events were defined as those requiring additional procedures. Next-generation sequencing (NGS) analysis was performed in each case of non-small cell lung cancer. Of the 100 patients, malignancy was confirmed in 94 cases. The diagnostic yield for TBLC/forceps biopsy/brushing cytology was 86/81/82% respectively, while the diagnostic yield for all procedures combined was 94%. There was no significant difference in the diagnostic yield between TBLC and forceps biopsy. When comparing the biopsy site, the diagnostic yield for TBLC at the lower lobe was significantly higher than forceps biopsy (P < 0.01). Endobronchial ultrasonography imaging using a guide-sheath did not significantly differ in the diagnostic yield of TBLC. The success rate of NGS for TBLC specimens was 100% (26 cases). Adverse events included two cases of severe bleeding. TBLC of peripheral lesions may improve the diagnostic yield when combined with forceps biopsy and brushing cytology. The diagnostic yield of TBLC was higher at the lower lobes. Furthermore, TBLC provided sufficient specimen quality for NGS.

Diagnostic performance of cryobiopsy guided by radial-probe EBUS with a guide sheath for peripheral pulmonary lesions

OBJECTIVE

Transbronchial lung cryobiopsy (TBCB) has developed rapidly and has become one of the research hotspots of lung biopsy technology. The present study sought to evaluate the efficacy of TBCB guided by radial-probe EBUS (RP-EBUS) and a guide sheath (GS) without fluoroscopy for peripheral pulmonary lesions.

METHODS

In this retrospective study, McNemar's test was used in order to compare TBCB and transbronchial forceps biopsy (TBFB) in terms of diagnostic performance. A multivariate logistic regression model was designed to explore the association between predictive variables and the diagnostic yield of TBCB.

RESULTS

A total of 168 patients underwent GS-guided RP-EBUS. Of those, 157 had lesions that were visible and 11 had lesions that were not. Of those 157 patients, 24 were excluded because of missing data or an unclear final diagnosis. Therefore, 133 patients underwent RP-EBUS-GS-guided TBFB and TBCB. The pooled diagnostic yield of RP-EBUS-GS-guided TBCB without fluoroscopy was 71.5% (103/144). In 133 patients, the diagnostic yield of TBCB was significantly higher than that of TBFB (77.4% vs. 59.4%; p < 0.05). Multivariate analysis indicated that lesion size and site were independently associated with the diagnostic yield of TBCB (OR = 2.8, p = 0.03 and OR = 4.1, p = 0.01, respectively), although cryoprobe size was not. There was no significant difference between the 1.1-mm cryoprobe and the 1.9-mm cryoprobe in terms of diagnostic performance (78.4% vs. 76.8%; p > 0.05).

CONCLUSIONS

GS-guided RP-EBUS is regarded as a practical option for guiding cryobiopsy, although it may not be able to replace fluoroscopy. Peripheral pulmonary lesions not located in the upper lobes or larger than 30 mm are significantly associated with a higher diagnostic yield of cryobiopsy.

Thin bronchoscopic cryobiopsy using a nasobronchial tube

BACKGROUND

Transbronchial lung cryobiopsy is useful when diagnosing lung lesions. However, prevention of associated bleeding complications is essential. This study aimed to evaluate the safety and efficacy of our novel bronchoscopic cryobiopsy technique, which uses a long nasobronchial tube to prevent blood flooding the central airway.

METHODS

Patients with localized or diffuse lung lesions were prospectively enrolled and underwent cryobiopsy using a 1.9 mm diameter cryoprobe and a 4.0 mm diameter thin bronchoscope under conscious sedation. For cryobiopsy, a long silicone tube (inner diameter, 5.0 mm) was advanced through the nose to the target bronchus, then wedged to drain blood under thin-tube bronchoscopic control. The primary endpoint was the frequency of bleeding complications.

RESULTS

Of the 80 patients initially enrolled, 73 that underwent at least one cryobiopsy were ultimately included. Mild bleeding during cryobiopsy occurred in 58 patients (79.5%), but there was no moderate or severe bleeding. Other complications occurred in four patients (two pneumothorax, one pneumomediastinum, and one pneumonia). Tube dislocation was noted in eight patients (11%). Cryobiopsy specimens were significantly larger than forceps biopsy specimens (9.0 mm² vs. 2.7 mm², P < .001) and allowed specific diagnoses in 50 patients (68.5%).

CONCLUSIONS

Thin bronchoscopic cryobiopsy using a nasobronchial tube in consciously sedated patients is safe and effective. Trial registration Date of registration: 24/06/2019. UMIN-Clinical Trials Registry; Identifier: UMIN000037156 https://www.umin.ac.jp/ctr/index.htm.

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.

Efficacy and Safety of Cryobiopsy vs. Forceps Biopsy for Interstitial Lung Diseases, Lung Tumors, and Peripheral Pulmonary Lesions: An Updated Systematic Review and Meta-Analysis

Background

Cryobiopsy has emerged as a novel alternative to conventional forceps biopsy for the diagnosis of interstitial lung diseases (ILDs), lung tumors, and peripheral pulmonary lesions (PPLs). This study aims to compare cryobiopsy and forceps biopsy for the diagnosis of these lung pathologies with respect to efficacy and safety by performing a meta-analysis of updated evidence.

Methods

A number of databases, such as PubMed, Embase, Web of Science, the Cochrane Library, OVID, CNKI, and Wanfang database, were searched for eligible studies. Randomized and non-randomized comparative studies investigating the efficacy and safety of cryobiopsy vs. forceps biopsy for lung pathologies were included. Pooled results were calculated as an odds ratio (OR) or standardized mean difference (SMD) with 95% CI.

Results

A total of 39 studies, such as 9 RCTs with 3,586 biopsies (1,759 cryobiopsies and 1,827 flexible forceps biopsies) were analyzed. Cryobiopsy was associated with a significant increase in the diagnostic rates of ILDs (OR, 4.29; 95% CI, 1.85–9.93; p < 0.01), lung tumors (OR, 3.58; 95% CI, 2.60–4.93; p < 0.01), and PPLs (OR, 1.70; 95% CI, 1.23–2.34; p < 0.01). Cryobiopsy yielded significantly larger specimens compared with flexible forceps biopsy (SMD, 3.06; 95% CI, 2.37–3.74; p < 0.01). The cryobiopsy group had a significantly higher (moderate to severe) bleeding risk than the forceps group (OR, 2.17; 95% CI, 1.48–3.19; p < 0.01). No significant difference was observed in the incidence of pneumothorax between the groups (OR, 0.90; 95% CI, 0.44–1.85; p = 0.78).

Conclusion

Our results demonstrate that cryobiopsy is a safe and efficacious alternative to conventional forceps biopsy.

Bronchoscopic diagnosis of peripheral lung lesions

PURPOSE OF REVIEW

Over the last decades, in addition to the traditional fluoroscopy, various and innovative guidance systems have been adopted in clinical practice for transbronchial approach to peripheral pulmonary lesions (PPLs). The aim of this article is to summarize the most recent data on available guidance systems and sampling tools, evaluating also advantages and limitations of each technique.

RECENT FINDINGS

Although several studies have been published over the last years, large randomized studies comparing the different techniques are scanty. Fluoroscopy is the traditional and still most widely utilized guidance system. New guidance systems (electromagnetic navigation bronchoscopy, ultrasound miniprobe, cone beam computed tomography) seems to provide a better sensitivity, especially for small lesions not visualized by fluoroscopy. Among the sampling instruments, there is a good evidence that flexible transbronchial needle provides the better diagnostic yield and that sensitivity may increase if more than one sampling instrument is used.

SUMMARY

Even if great progress has been done since the first articles on the transbronchial approach to PPLs, better scientific evidence and more reliable randomized trials are needed to guide interventional pulmonologists in choosing the best technique according to different clinical scenarios and source availability.