Transbronchial Lung Cryobiopsy for Interstitial Lung Disease Diagnosis: A Perspective From Members of the Pulmonary Pathology Society

Evaluation of large airway specimens obtained by transbronchial lung cryobiopsy in diffuse parenchymal lung diseases

Background

The difference in diagnostic yield between surgical lung biopsy and transbronchial lung cryobiopsy (TBLC) in diffuse parenchymal lung diseases (DPLD) has been reported to be due to differences in the rate of interpathologist agreement, specimen size, and specimen adequacy. In TBLC, the specimens containing large airway components are generally believed as inadequate specimens for histological evaluation, but the detailed characteristics of TBLC specimens including the large airway and the impact on histological diagnostic rates of DPLD have not been investigated.

Methods

We retrospectively reviewed the specimen characteristics of patients with DPLD who underwent TBLC.

Results

Between February 2018 and January 2020, 74 patients and 177 specimens were included. There were 85 (48.0%) large airway specimens (LAS) that contained bronchial gland or bronchial cartilage. The ideal specimen ratio was significantly lower in the LAS-positive group than that in the LAS-negative group (5.8% vs. 45.6%), and the proportion of bronchioles, alveoli, and perilobular area were similarly lower in the LAS-positive group. The presence of traction bronchiectasis and diaphragm overlap sign on high-resolution computed tomography (HRCT) were also significantly higher in the LAS-positive group than those in the LAS-negative group. We observed a statistically significant trend in histological diagnostic yield (40.7% in LAS positive group; 60.8% in LAS positive and negative group; 91.6% in LAS negative group) (Cochran-Armitage trend test).

Conclusion

LAS is a specimen often collected in TBLC and contains a low percentage of bronchioles, alveoli, and perilobular area. Since the histological diagnostic yield tends to be higher in cases that do not contain LAS, it may be important to determine the biopsy site that reduces the frequency of LAS collection by referring to the HRCT findings in TBLC.

Clinical Value of Bronchoscopy in Acute Respiratory Failure

Bronchoscopy may be considered the “added value” in the diagnostic and therapeutic pathway of different clinical scenarios occurring in acute respiratory critically ill patients. Rigid bronchoscopy is mainly employed in emergent clinical situations due to central airways obstruction, haemoptysis, and inhaled foreign body. Flexible bronchoscopy (FBO) has larger fields of acute applications. In intensive care settings, FBO is useful to facilitate intubation in difficult airways, guide percutaneous dilatational tracheostomy, and mucous plugs causing lobar/lung atelectasis. FBO plays a central diagnostic role in acute respiratory failure caused by intra-thoracic tumors, interstitial lung diseases, and suspected severe pneumonia. “Bronchoscopic” sampling has to be considered when “non-invasive” techniques are not diagnostic in suspected ventilator-associated pneumonia and in non-ventilated immunosuppressed patients. The combined use of either noninvasive ventilation (NIV) or High-flow nasal cannula (HFNC) with bronchoscopy is useful in different scenarios; the largest body of proven successful evidence has been found for NIV-supported diagnostic FBO in non-ventilated high risk patients to prevent and avoid intubation. The expected diagnostic/therapeutic goals of acute bronchoscopy should be balanced against the potential severe risks (i.e., cardio-pulmonary complications, bleeding, and pneumothorax). Expertise of the team is fundamental to achieve the best rate of success with the lowest rate of complications of diagnostic and therapeutic bronchoscopic procedures in acute clinical circumstances.

The Application of Transbronchial Lung Cryobiopsy and Uniportal and Tubeless Video-Assisted Thoracic Surgery in the Multidisciplinary Diagnosis of Interstitial Lung disease-A Real-World Prospective Study

The application of transbronchial lung cryobiopsy (TBLC) and uniportal and tubeless video-assisted thoracic surgery (UT-VATS) in the multidisciplinary diagnosis of interstitial lung disease (ILD) has not been demonstrated in real-world clinical practice. This prospective study included 137 patients with no definitive diagnosis who were the subject of two multidisciplinary discussion (MDD) sessions. As indicated in the first MDD, 67 patients underwent UT-VATS and 70 underwent TBLC. The specificity of biopsy information and its contribution to final MDD diagnosis were evaluated in the second MDD. The post-operative complications and hospitalization costs associated with the two biopsy methods were compared. UT-VATS was favored for patients initially diagnosed with idiopathic pulmonary fibrosis (IPF), bronchiolitis-associated interstitial lung disease (RB-ILD)/desquamative interstitial pneumonia (DIP) and undefined idiopathic interstitial pneumonia (UIIP), while TBLC was preferred for pulmonary lymphangioleiomyomatosis (PLAM) and pulmonary alveolar proteinosis (PAP). The spirometry parameters were better in patients who underwent UT-VATS than those who underwent TBLC. UT-VATS provided more specific pathological results than TBLC (85.7 vs 73.7%, p = 0.06). In patients initially diagnosed with UIIP, pathological information from UT-VATS was more clinically useful than that obtained from TBLC, although both tests contributed similarly to cases initially diagnosed as interstitial pneumonia with auto-immune features (IPAF)/connective tissue disease-related ILD (CTD-ILD). The safety of UT-VATS was comparable with TBLC although TBLC was cheaper during hospitalization (US$4,855.7 vs US$3,590.9, p < 0.001). multidisciplinary discussion decisions about biopsies were driven by current knowledge of sampling and diagnosis capacity as well as potential risks of different biopsy methods. The current MDD considered UT-VATS more informative than TBLC in cases initially diagnosed as UIIP although they were equally valuable in patients initially diagnosed with IPAF/CTD-ILD.

Transbronchial lung cryobiopsy for connective tissue disease-related interstitial lung disease and interstitial pneumonia with autoimmune features: a single center retrospective case series

OBJECTIVE

Transbronchial lung cryobiopsy (TBLC) has been recently introduced for diagnosing interstitial lung diseases. We aimed to assess the effectiveness and safety of TBLC by identifying the specific patterns of histology in the diagnosis of connective tissue disease-related interstitial lung disease (CTD-ILD) and interstitial pneumonia with autoimmune features (IPAF).

METHODS

The clinical-radiological-pathological data from the Affiliated Hospital of Guilin Medical University between July 1, 2017, and October 31, 2020, of patients whose clinical-radiological or clinical-radiological-pathological diagnosis was CTD-ILD or IPAF and who underwent TBLC, transbronchial lung biopsy (TBLB), or surgical lung biopsy were retrospectively analyzed and summarized with review. The size of biopsy samples, complications, and diagnostic yield were compared.

RESULTS

Fourteen patients met the inclusion criteria, of whom 12 underwent TBLC, 1 underwent TBLB, and 1 underwent each procedure at different times. Compared to the size of TBLB specimens (5.625 ± 0.479 mm²), the size of TBLC specimens (12.00 (12.00, 15.00) mm²) was much larger (Z = - 3.262, P = 0.001). The diagnostic yields of TBLC and TBLB were 100.00% (13/13) and 0.00% (2/2), respectively (P = 0.0095). The most frequent complication was mild bleeding. The risk of bleeding between TBLB (1/2, 50.00%) and TBLC (10/13, 76.92%) did not differ significantly (P = 0.469).

CONCLUSION

TBLC can add extra diagnostic value by effectively identifying specific types of histology for patients with suspected CTD-ILD or IPAF, with a procedure that is safe from adverse events. Key Points • Transbronchial lung cryobiopsy has been introduced recently for diagnosing interstitial lung disease. • Transbronchial lung cryobiopsy was found to be effective and safe in the diagnosis for patients with suspected interstitial lung disease. It can be used as a preferred method for biopsy when the clinical-radiological diagnosis is uncertain.

Diagnostic approach in parenchymal lung diseases: transbronchial lung biopsy or cryobiopsy?

Background/aim

Diagnosis of interstitial lung diseases requires a multidisciplinary approach, and a gold standard for histological diagnosis is open lung biopsy. Transbronchial lung biopsy (TBLB) and in recent years an alternative method, cryobiopsy (TBLC), are used for the diagnosis of parenchymal lung lesions. The aim of this study is to compare the efficacy of concomitant conventional TBLB and TBLC.

Materials and methods

A total of 82 patients who underwent TBLC for diagnosis of diffuse parenchymal lung diseases at Dr. Suat Seren Chest Diseases and Surgery Training and Research Hospital between 2015 and 2018 were screened retrospectively and included in the study. Of the patients, 53.7% (n: 44) were male, and 46.4% (n:38) of them were female. The mean age was 58.37 (±9.33) years. First TBLB and then TBLC were performed to all patients in the same session and their diagnostic performances were compared.

Results

Although both procedures were done in the same session, 45 patients (54.9%) were diagnosed with TBLB and 75 patients (91.5%) were diagnosed with TBLC (P ˂ 0.001). Hemorrhage was observed in 39 patients (47.6%), but only one had a massive hemorrhage. Pneumothorax was observed in 6 patients (7.3%) and none of them required tube drainage.

Conclusion

Transbronchial lung cryobiopsy is a promising technique for the diagnosis of parenchymal lung diseases compared to transbronchial lung biopsy. 

Introducing transbronchial cryobiopsies in diagnosing diffuse parenchymal lung diseases in Greece: Implementing training into clinical practice

Introduction

Diffuse parenchymal lung diseases (DPLD) constitute a heterogeneous group of disorders, sometimes requiring surgical lung biopsies (SLB) to obtain a definite diagnosis. Transbronchial cryobiopsy (TBCB) is a new promising interventional bronchoscopic method of obtaining lung tissue that is gaining ground against SLB.

Methods

Fifty consecutive patients with indeterminate DPLD (definite/possible UIP excluded), after expert panel review referral, were retrospectively analyzed from January 2016 to August 2018. Patients underwent TBCB under deep sedation with endotracheal intubation and spontaneous breathing at a single, tertiary-care, reference hospital.

Results

A total of 110 TBCBs (2.7 per patient, range 1 to 4) were performed. Frequent complications included mild pneumothorax in 5 patients (10%), requiring only oxygen supplementation, and bleeding in 31 patients (62%) that was mild in 19 patients and moderate in 12 patients. No serious bleeding was observed. There was zero mortality and no serious adverse events. Adequate samples for diagnostic purposes were obtained in 46 patients (92%) and pathologic histologic diagnosis was reached in 40 patients (80%). The most frequent histopathological patterns were organizing pneumonia (OP) (25%) and non-specific interstitial pneumonia (NSIP) (15%). After an expert panel review of all cases a final diagnosis was achieved in 38 patients, corresponding to a diagnostic yield of 76% for TBCB.

Conclusion

Our single center cohort demonstrates that establishing TBCBs as a new technique is safe and feasible after proper training in specialized centers, resulting in low complication rates and adequate diagnostic yields.

Transbronchial Lung Cryobiopsy in the Diagnosis of Interstitial Lung Disease: A Retrospective Single-center Experience

BACKGROUND

Surgical lung biopsy (SLB) is the gold standard to aid diagnosis of interstitial lung disease (ILD). Complication rates are restrictive as routine approach for all patients with ILD. Transbronchial lung cryobiopsy (TBLC) is presumed to be a safe, less invasive alternative to assist multidisciplinary discussions regarding the diagnosis of ILD. Varying practice patterns and lack of consistent guidelines prohibit wide support of this technique. The purpose of this study was to evaluate safety and diagnostic yield of TBLC, with highlight of distinct technical features, in ILD.

METHODS

Retrospective study of patients with ILD on the basis of high-resolution chest computed tomography who underwent TBLC.

RESULTS

Of 121 TBLC, 40 patients (mean age, 57.2±13 y; 28 men) with ILD were referred for biopsy. Procedures were performed in endoscopy suite (60%) or operating room by using 1.9-mm cryoprobe. Biopsies were performed in 2 lobes with at least 3 to 5 specimens >5 mm in diameter. The average diameter and area of specimens were 5.7±2 mm and 40±2 mm, respectively. The most common diagnosis was nonspecific interstitial pneumonitis; usual interstitial pneumonia was diagnosed in 1 patient. Of 6 nondiagnostic specimens, 2 underwent SLB with subsequent diagnoses. Final histopathologic diagnostic rate was 85%. Bleeding was the most frequent complication.

CONCLUSION

We provided a detailed description of our TLBC technique and highlighted areas of similarity and differences among comparative studies and attest that TBLC is a safe alternative to SLB in the diagnosis of ILD. Our data also indicated the tendency for moderate-to-severe bleeding occurred more in the endoscopy suite.

Clusterization of patients with idiopathic pulmonary fibrosis with chemokine receptors: a possible role in the diagnostic work-up of idiopathic pulmonary fibrosis?

Background and objective: Idiopathic pulmonary fibrosis (IPF) is a chronic and irreversible interstitial lung disease whose diagnosis often requires surgical lung biopsies (SLB) in cases without consistent radiological findings. We previously published that the expression of the chemokine receptors CXCR3 and CCR4 on T cells is significantly different in bronchoalveolar lavage (BAL) of IPF patients from other interstitial lung diseases. The aim of the study was to evaluate cut-off values of CXCR3 and CCR4 receptors expressed on bronchoalveolar lavage (BAL) and peripheral blood (PB) T cells useful for a differential diagnosis. Methods: Ninety-three patients were enrolled: 35 IPF, 36 interstitial lung diseases (nIPF) and 22 sarcoidosis. CXCR3 and CCR4 were evaluated on BAL and PB T lymphocytes with flow cytometry. Results: Among PB and BAL variables considered, the values of the ratio of BAL and PB CXCR3 on CD4 cells were clustered in the most informative way to obtain a classification rule for the diagnosis of patients without steroid therapy (n = 66/93). Patients with a CXCR3 ratio BAL/PB on CD4 T cells lower or equal than 1.43 were assigned to the IPF group with sensitivity = 0.87 and specificity = 0.90. All the other variables considered showed lower sensitivity and specificity in discriminating IPF patients. Conclusions: The evaluation of chemokine receptors on BAL and PB T lymphocytes could aid to discriminate IPF in subjects without steroid therapy, particularly in those patients with a high-resolution computed tomography (HRCT) non typical for Usual Interstitial Pneumonia (UIP). (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 35-43).

Learning curve for transbronchial lung cryobiopsy in diffuse lung disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is increasingly used in the diagnosis of diffuse lung disease (DLD), but no data have yet been published on the learning curve associated with this technique.

AIM

To evaluate diagnostic yield, lung tissue sample length and area, and procedure-related complications in a cohort of TBLC procedures to define the learning curve and threshold for proficiency.

METHODS

Retrospective analysis of the first 100 TBLCs performed in different segments of the same lobe in patients with suspected DLD. We compared diagnostic yield, sample length and area, and complications between consecutive groups of patients.

RESULTS

The overall diagnostic yield for TBLC was 82%. Median sample length was 5.4mm (IQR, 5-6) and median area was 19.5mm2 (IQR, 13.3-25). Pneumothorax was the most common complication (18%). On comparing the two groups of 50 consecutive patients, a significant difference was found for diagnostic yield (74% vs 90%; p=0.04), sample length (5.0mm [2.5-16] vs 6.0mm [4-12;] p<0.01) and area (17.5mm2 [6-42] vs 21.5mm2 [10-49]; p<0.01). Logarithm regression was applied to median diagnostic yield and sample length and area for groups of 10 consecutive patients to define the learning curve, which plateaued after approximately 70 procedures.

CONCLUSIONS

Our findings suggest that proficiency in TBLC is achieved at approximately the 70th procedure; however they need to be validated in more series and cohorts.

Interstitial lung disease: the diagnostic role of bronchoscopy

Interstitial lung diseases (ILDs) form one of the most fascinating fields in pulmonary medicine. They also pose one of the greatest challenges for accurate diagnosis and proper treatment. Even within the recommended and warranted multidisciplinary approach, differentiating between one disease and another may lead to frustration, especially when proper lung tissue is not available for adequate pathological review. A surgical lung biopsy (SLB) might render enough tissue for histopathology, but this could come at the expense of high morbidity and even mortality, as in the case of usual interstitial pneumonia (UIP). Could bronchoscopy and its various techniques offer a safer and higher yield alternative? Since the very late 19th century, efforts have been made to better examine the airways, obtain tissue and treat various conditions. This resulted in the successive emergence of bronchoalveolar lavage (BAL), endobronchial and transbronchial forceps biopsies, until recently when transbronchial cryobiopsy surfaced as a nascent technique with much promise. The use of endobronchial ultrasound revolutionized the diagnosis and staging of lung cancer, while adding to the yield of other conditions such as sarcoidosis. Ongoing research, efforts and studies have continuously scrutinized the roles of various techniques in the approach to ILDs. For example, BAL seems to serve mostly to eliminate infection as an etiology or a complicating factor in the acute worsening of a fibrotic lung disease, while a predominant cellular component might be diagnostic, such as eosinophilia in eosinophilic lung disease, or lymphocytosis in hypersensitivity pneumonitis (HP). On the other hand, endobronchial biopsy's (EBB) role appears limited to sarcoidosis. As for transbronchial biopsy by forceps, the small sample size and related artifact appear to be limiting factors in making an accurate diagnosis. Recently, however, the use of cryotherapy via employing a cryoprobe in obtaining transbronchial lung biopsies is unfolding into a refined interventional method which might transform indefinitely our approach to the pathological diagnosis of the various ILDs.

Transbronchial cryobiopsy for diffuse parenchymal lung disease: a state-of-the-art review of procedural techniques, current evidence, and future challenges

Transbronchial lung biopsy with a cryoprobe, or cryobiopsy, is a promising new bronchoscopic biopsy technique capable of obtaining larger and better-preserved samples than previously possible using traditional biopsy forceps. Over two dozen case series and several small randomized trials are now available describing experiences with this technique, largely for the diagnosis of diffuse parenchymal lung disease (DPLD), in which the reported diagnostic yield is typically 70% to 80%. Cryobiopsy technique varies widely between centers and this predominantly single center-based retrospective literature heterogeneously defines diagnostic yield and complications, limiting the degree to which this technique can be compared between centers or to surgical lung biopsy (SLB). This review explores the broad range of cryobiopsy techniques currently in use, their rationale, the current state of the literature, and suggestions for the direction of future study into this promising but unproven procedure.

Recent advances in diagnostic bronchoscopy

The field of diagnostic bronchoscopy has been revolutionized in the last decade primarily with the advent of endobronchial ultrasound (EBUS) but also with the addition of multiple different techniques for "guided-bronchoscopy". These advances have had a substantial impact in the management of lung cancer with bronchoscopy now providing both diagnosis and mediastinal staging in a single procedure. EBUS has, in fact, become the first choice for staging of the mediastinum over cervical mediastinoscopy (CM). Although EBUS is now a well-established technique, there are continuous efforts from the scientific community to improve its diagnostic performance, and these will be reviewed in this manuscript. The term "guided-bronchoscopy" was recently coined to describe a myriad of techniques that guide our bronchoscopes or bronchoscopic tools into the periphery of the lungs in addition to our conventional fluoroscopy. Electromagnetic and non-electromagnetic navigation, thin and ultrathin scopes, as well as radial-probe EBUS have collectively increased our yield for smaller peripheral lung lesions and continue to evolve. Despite this improved diagnostic yield, there is still ample room for improvement and newer techniques are under way. With new therapies available for patients with interstitial lung disease, achieving a specific histologic diagnosis is now of paramount importance. Given the high morbidity and mortality of surgical biopsies, bronchoscopic cryobiopsy is being rapidly adopted as a safer and effective alternative, and it is likely going to play a major role in the management of these diseases in the near future. This manuscript we will focus on recent advances in EBUS, guided-bronchoscopy, and the use of cryobiopsy.