Comparison of Transbronchial and Cryobiopsies in Evaluation of Diffuse Parenchymal Lung Disease

The efficacy and safety of modified transbronchial cryobiopsy in the diagnosis of interstitial lung disease

The objective of this study is to investigate the efficacy and safety of flexible transbronchial cryobiopsy (TBCB) in the diagnosis of diffuse parenchymal lung disease (DPLD) in a routine bronchoscopy examination room under analgesia and sedation, using neither endotracheal intubation or rigid bronchoscope nor fluoroscopy or general anesthesia. The data from 50 DPLD patients with unknown etiology who were treated in the Affiliated Hospital of Guilin Medical College from May 2018 to September 2020 were collected, and 43 were eventually included. The specimens obtained from these 43 patients were subjected to pathological examination, pathogenic microorganism culture, etc, and were analyzed in the clinical-radiological-pathological diagnosis mode to confirm the efficacy of TBCB in diagnosing the cause of DPLD. Subsequently, the intraoperative and postoperative complications of TBCB and their severity were closely observed and recorded to comprehensively evaluate the safety of TBCB. For the 43 patients included, a total of 85 TBCB biopsies were performed (1.98 [1, 4] times/case), and 82 valid tissue specimens were obtained (1.91 [1, 4] pieces/case), accounting for 96.5% (82/85) of the total sample. The average specimen size was 12.41 (1, 30) mm2. Eventually, 38 cases were diagnosed, including 11 cases of idiopathic pulmonary fibrosis, 5 cases of connective tissue-related interstitial lung disease, 5 cases of nonspecific interstitial pneumonia, 4 cases of tuberculosis, 4 cases of occupational lung injury, 3 cases of interstitial pneumonia with autoimmune characteristics, 1 case of lung cancer, 2 cases of interstitial lung disease (unclassified interstitial lung disease), 1 case of hypersensitivity pneumonitis, 1 case of pulmonary alveolar proteinosis, and 1 case of fungal infection. The remaining 5 cases were unclarified. For infectious diseases, the overall etiological diagnosis rate was 88.4% (38/43). With respect to complications, pneumothorax occurred in 4 cases (9.3%, 4/43, including 1 mild case and 3 moderate cases), of which 3 cases (75%) were closed by thoracic drainage and 1 case (25%) was absorbed without treatment. In addition, 22 cases experienced no bleeding (51.2%) and 21 cases suffered bleeding to varying degrees based on different severity assessment methods. TBCB is a minimally invasive, rapid, economical, effective, and safe diagnostic technique.

Assessing the effectiveness and safety of transbronchial lung cryobiopsy utilizing a flexible bronchoscope with an endobronchial blocker in diffuse parenchymal lung lesions

Transbronchial lung cryobiopsy (TBLC) with flexible bronchoscope represents an encouraging modality to obtain a larger size specimen without crush artifact, and a higher diagnostic yield in patients with diffuse parenchymal lung lesions/diseases as compared to conventional transbronchial lung biopsy, and fewer complications as opposed to surgical lung biopsy. Artificial airway is preferred as it provides better airway protection in cases of severe bleeding. Although various researchers have published data on different modalities, the data is not sufficient to standardize a single technique. This study describes the procedural technique, safety, and yield of TBLC using a flexible bronchoscope with an endobronchial blocker. We performed a retrospective analysis of 100 consecutive patients who underwent TBLC using flexible bronchoscopy from May 2018 to June 2022. TBLC samples were obtained under moderate sedation without the use of artificial airway or fluoroscopy. Among the 100 patients, the majority were male (63%). The mean age of the enrolled patients was 44.43±15.92 years. The predominant diagnoses in our study were hypersensitivity pneumonitis (27%), followed by sarcoidosis (12%) and tuberculosis (10%). We obtained alveolated lung tissue in 90 out of 100 cases with a median biopsy size of 5 mm (in greatest dimension, interquartile range 5-4 mm), resulting in a specific histopathological diagnosis in 82 cases. The most frequent complications were bleeding and pneumothorax (13%). Mild bleeding occurred in 58% of the patients, and moderate bleeding occurred in 20% of the patients. There was no episode of severe/life-threatening bleeding. None of the patients required intensive care unit admission or endotracheal intubation. In conclusion, the use of TBLC through flexible bronchoscopy with an endobronchial blocker emerges as a minimally invasive, secure, time-efficient, and readily reproducible technique. Significantly, this procedure can be seamlessly executed in the bronchoscopy suite, eliminating the requirement for an artificial airway or general anesthesia.

ATS/JRS/ALAT Hypersensitivity Pneumonitis Guidelines for Diagnosis of humidifier lung and summer-type hypersensitivity pneumonitis

BACKGROUND

The ATS/JRS/ALAT Guidelines for the Diagnosis of Hypersensitivity Pneumonitis (GL for HP) were published in 2020. Humidifier lung and summer-type HP are forms of HP, but it is unclear whether they can be diagnosed using GL for HP. This study examined the level of confidence where humidifier lung and summer-type HP can be diagnosed with GL for HP.

METHODS

Data from 23 patients with humidifier lung and 20 patients with summer-type HP (mean age, 67.3 and 57.4 years, respectively) diagnosed between October 2012 and January 2022 were retrospectively reviewed. We evaluated high resolution computed tomography (HRCT) patterns, bronchoalveolar lavage fluid (BALF) findings, exposures, and histopathological findings to determine the level of confidence where a diagnosis of HP could be made using the GL for HP.

RESULTS

HRCT pattern was classified as typical HP in 5 (22%) and compatible with HP in 18 (78%) patients with humidifier lung and considered as typical HP in 17 (85%) and compatible with HP in 3 (15%) patients with summer-type. The confidence level for diagnosis of HP was definite in 2 (8.7%), moderate in 14 (60.9%), and low in 7 (30.4%) patients with humidifier lung. It was definite in 12 (60%), high in 3 (15%), and moderate in 5 (25%) patients with summer-type HP.

CONCLUSIONS

GL for HP showed utility in diagnosing humidifier lung in many patients with a moderate to low confidence. However, there was a definite to high confidence for patients with summer-type HP.

Role of Transbronchial Lung Cryobiopsy in the Diagnosis of Interstitial Lung Disease: A Meta-analysis of 68 Studies and 6300 Patients

BACKGROUND

Diagnosis of interstitial lung disease (ILD) is based on multidisciplinary team discussion (MDD) with the incorporation of clinical, radiographical, and histopathologic information if available. We aim to evaluate the diagnostic yield and safety outcomes of transbronchial lung cryobiopsy (TBLC) in the diagnosis of ILD.

METHODS

We conducted a meta-analysis by comprehensive literature search to include all studies that evaluated the diagnostic yields and/or adverse events with TBLC in patients with ILD. We calculated the pooled event rates and their 95% confidence intervals (CIs) for the diagnostic yield by MDD, histopathologic diagnostic yield, and various clinical adverse events.

RESULTS

We included 68 articles (44 full texts and 24 abstracts) totaling 6386 patients with a mean age of 60.7±14.1 years and 56% men. The overall diagnostic yield of TBLC to achieve a definite or high-confidence diagnosis based on MDD was 82.3% (95% CI: 78.9%-85.2%) and histopathologic diagnosis of 72.5% (95% CI: 67.7%-76.9%). The overall rate of pneumothorax was 9.6% (95% CI: 7.9%-11%), while the rate of pneumothorax requiring drainage by a thoracostomy tube was 5.3% (95% CI: 4.1%-6.9%). The rate of moderate bleeding was 11.7% (95% CI: 9.1%-14.9%), while the rate of severe bleeding was 1.9% (95% CI: 1.4%-2.6%). The risk of mortality attributed to the procedure was 0.9% (95% CI: 0.7%-1.3%).

CONCLUSION

Among patients with undiagnosed or unclassified ILD requiring tissue biopsy for diagnosis, transbronchial cryobiopsy represents a reliable alternative to surgical lung biopsy with decreased incidence of various clinical adverse events.

[Consensus guideline on the interdisciplinary diagnosis of interstitial lung diseases]

The evaluation of a patient with interstitial lung disease (ILD) includes assessment of clinical, radiological, and often histopathological data. As there were no specific recommendations to guide the evaluation of patients under the suspicion of an ILD within the German practice landscape, this position statement from an interdisciplinary panel of ILD experts provides guidance related to the diagnostic modalities which should be used in the evaluation of ILD. This includes clinical assessment rheumatological evaluation, radiological examinations, histopathologic sampling and the need for a final discussion in a multidisciplinary team.

Use of a pulmosphere model to evaluate drug antifibrotic responses in interstitial lung diseases

BACKGROUND

Interstitial lung diseases (ILD) encompass a heterogenous group of diffuse parenchymal lung disorders characterized by variable degrees of inflammation and fibrosis. Pretherapeutic clinical testing models for such diseases can serve as a platform to test and develop effective therapeutic strategies. In this study, we developed patient derived 3D organoid model to recapitulate the disease process of ILDs. We characterized the inherent property of invasiveness in this model and tested for antifibrotic responses with an aim to develop a potential platform for personalized medicine in ILDs.

METHODS

In this prospective study, 23 patients with ILD were recruited and underwent lung biopsy. 3D organoid-based models (pulmospheres) were developed from the lung biopsy tissues. Pulmonary functioning testing and other relevant clinical parameters were collected at the time of enrollment and follow up visits. The patient derived pulmospheres were compared to normal control pulmospheres obtained from 9 explant lung donor samples. These pulmospheres were characterized by their invasive capabilities and responsiveness to the antifibrotic drugs, pirfenidone and nintedanib.

RESULTS

Invasiveness of the pulmospheres was measured by the zone of invasiveness percentage (ZOI%). The ILD pulmospheres (n = 23) had a higher ZOI% as compared to control pulmospheres (n = 9) (516.2 ± 115.6 versus 54.63 ± 19.6 respectively. ILD pulmospheres were responsive to pirfenidone in 12 of the 23 patients (52%) and responsive to nintedanib in all 23 patients (100%). Pirfenidone was noted to be selectively responsive in patients with connective tissue disease related ILD (CTD-ILD) at low doses. There was no correlation between the basal pulmosphere invasiveness, response to antifibrotics, and FVC change (Δ FVC).

CONCLUSIONS

The 3D pulmosphere model demonstrates invasiveness which is unique to each individual subject and is greater in ILD pulmospheres as compared to controls. This property can be utilized to test responses to drugs such as antifibrotics. The 3D pulmosphere model could serve as a platform for the development of personalized approaches to therapeutics and drug development in ILDs and potentially other chronic lung diseases.

Diagnostic yield and safety of transbronchial lung cryobiopsy and surgical lung biopsy in interstitial lung diseases: a systematic review and meta-analysis

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is increasingly being used as an alternative to video-assisted thoracoscopic surgery (VATS) biopsy to establish the histopathologic pattern in interstitial lung disease (ILD).

METHODS

A systematic literature search of the PubMed and Embase databases, from October 2010 to October 2020, was conducted to identify studies that reported on diagnostic yield or safety of VATS or TBLC in the diagnosis of ILD.

RESULTS

43 studies were included. 23 evaluated the diagnostic yield of TBLC after multidisciplinary discussion, with a pooled diagnostic yield of 76.8% (95% confidence interval (CI) 70.6-82.1), rising to 80.7% in centres that performed ≥70 TBLC. 10 studies assessed the use of VATS and the pooled diagnostic yield was 93.5% (95% CI 88.3-96.5). In TBLC, pooled incidences of complications were 9.9% (95% CI 6.8-14.3) for significant bleeding (6.9% for centres with ≥70 TBLC), 5.6% (95% CI 3.8-8.2) for pneumothorax treated with a chest tube and 1.4% (95% CI 0.9-2.2) for acute exacerbation of ILD after TBLC. The mortality rates were 0.6% and 1.7% for TBLC and VATS, respectively.

CONCLUSIONS

TBLC has a fairly good diagnostic yield, an acceptable safety profile and a lower mortality rate than VATS. The best results are obtained from more experienced centres.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, full version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

Is conventional transbronchial lung biopsy out: The evaluation of clinical value in diffuse parenchymal lung disease

Introduction

Transbronchial lung biopsy (TBLB) is a relatively safe technique routinely employed by pulmonologists for the diagnosis of diffuse parenchymal lung disease (DPLD). Cryobiopsy is associated with higher diagnostic yield and a favorable risk/benefit ratio. Nevertheless, TBLB remains the representative method for definite diagnosis in developing countries.

Objectives

This study aimed to evaluate whether the results obtained from TBLB had clinical value to pulmonologists in the management of DPLD.

Methods

We performed a retrospective analysis of patients who underwent conventional TBLB for the diagnosis of DPLD from May 1, 2017, to April 30, 2019, at the Beijing Chao‐yang Hospital, Capital Medical University. The clinical value of TBLB was defined as leading to a specific histopathological diagnosis or being consistent with the clinical and radiological data.

Results

Seven hundred and forty‐three patients with suspected DPLD were recruited. Conventional TBLB was considered clinically valuable in 439 procedures (59.1%), including 360 cases provided with definitive histopathological diagnoses, and 79 cases that were consistent with the working diagnoses. Among the 439 cases of clinically valuable TBLBs, 88 (20.0%), 37, 77 (10.7%), and 61 (13.9%) cases were diagnosed as connective tissue disease‐related interstitial lung disease, definite histopathological diagnoses, malignancies, and nonspecific interstitial pneumonia, respectively.

Conclusions

Conventional TBLB served as a key determinant or provided supplementary information in the final diagnosis of non‐infectious DPLDs. TBLB decision‐making should therefore be based on clinical and radiological data.

French practical guidelines for the diagnosis and management of idiopathic pulmonary fibrosis - 2021 update. Full-length version

BACKGROUND

Since the latest 2017 French guidelines, knowledge about idiopathic pulmonary fibrosis has evolved considerably.

METHODS

Practical guidelines were drafted on the initiative of the Coordinating Reference Center for Rare Pulmonary Diseases, led by the French Language Pulmonology Society (SPLF), by a coordinating group, a writing group, and a review group, with the involvement of the entire OrphaLung network, pulmonologists practicing in various settings, radiologists, pathologists, a general practitioner, a health manager, and a patient association. The method followed the "Clinical Practice Guidelines" process of the French National Authority for Health (HAS), including an online vote using a Likert scale.

RESULTS

After a literature review, 54 guidelines were formulated, improved, and then validated by the working groups. These guidelines addressed multiple aspects of the disease: epidemiology, diagnostic procedures, quality criteria and interpretation of chest CT scans, lung biopsy indication and procedures, etiological workup, methods and indications for family screening and genetic testing, assessment of the functional impairment and prognosis, indication and use of antifibrotic agents, lung transplantation, management of symptoms, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are intended to guide the diagnosis and practical management of idiopathic pulmonary fibrosis.

Transbronchial Lung Cryobiopsy for Diffuse Parenchymal Lung Disease

Transbronchial lung cryobiopsy (TBLC) offers a minimally invasive option for the diagnosis of diffuse parenchymal lung diseases, of which interstitial lung diseases comprise the most common diagnoses. It has a high diagnostic yield with prognostic and therapeutic implications. TBLC has a favorable safety profile compared with surgical lung biopsy, but associated complications include pneumothorax and bleeding. However, TBLC techniques remain variable. Here we review the latest techniques described to maximize diagnostic yield and mitigate complications of TBLC as well as how this modality has been incorporated into guidelines.

The safety profile of a protocolized transbronchial cryobiopsy program utilizing a 2.4 mm cryoprobe for interstitial lung disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) has emerged as a promising alternative to surgical lung biopsy for the diagnosis of interstitial lung disease. However, uncertainty remains regarding its overall complications due to a lack of procedural standardization including the size of cryoprobe utilized.

METHODS

This is a prospective cohort study of a protocolized transbronchial cryobiopsy program utilizing a 2.4 mm cryoprobe. 201 consecutive subjects were enrolled at a single academic center.

RESULTS

The average biopsy size was 106.2 ± 39.3 mm². Complications included a total pneumothorax rate of 4.9% with 3.5% undergoing chest tube placement. Severe bleeding defined by the Nashville Working Group occurred in 0.5% of cases. There were no deaths at 30-days.

DISCUSSION

A protocolized transbronchial cryobiopsy program utilizing a 2.4 mm cryoprobe in can achieve a high diagnostic yield with a favorable safety profile.

Transbronchial Lung Cryobiopsy in Patients with Interstitial Lung Disease: A Systematic Review

RATIONALE

In 2018, a systematic review evaluating transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) was performed to inform American Thoracic Society (ATS), European Respiratory Society (ERS), Japanese Respiratory Society (JRS), and Asociación Latinoamericana del Tórax (ALAT) clinical practice guidelines on the diagnosis of idiopathic pulmonary fibrosis (IPF).

OBJECTIVE

To perform a new systematic review to inform updated guidelines.

METHODS

Medline, EMBASE and the Cochrane Central Register of Controlled Trials (CCTR) were searched through June 2020. Studies that enrolled patients with ILD and reported the diagnostic yield or complication rates of TBLC were selected for inclusion. Data was extracted and then pooled across studies via meta-analysis. The quality of the evidence was appraised using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

Histopathologic diagnostic yield (number of procedures that yielded a histopathologic diagnosis divided by the total number of procedures performed) of TBLC was 80% (95% CI 76-83%) in patients with ILD. TBLC was complicated by bleeding and pneumothorax in 30% (95% CI 20-41%) and 8% (95% CI 6-11%) of patients, respectively. Procedure-related mortality, severe bleeding, prolonged air leak, acute exacerbation, respiratory failure, and respiratory infection were rare. The quality of the evidence was very low due to the uncontrolled study designs, lack of consecutive enrollment, and inconsistent results.

CONCLUSION

Very low-quality evidence indicated that TBLC has a diagnostic yield of approximately 80% in patients with ILD, with manageable complications.

Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline

Background: This American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana de Tórax guideline updates prior idiopathic pulmonary fibrosis (IPF) guidelines and addresses the progression of pulmonary fibrosis in patients with interstitial lung diseases (ILDs) other than IPF. Methods: A committee was composed of multidisciplinary experts in ILD, methodologists, and patient representatives. 1) Update of IPF: Radiological and histopathological criteria for IPF were updated by consensus. Questions about transbronchial lung cryobiopsy, genomic classifier testing, antacid medication, and antireflux surgery were informed by systematic reviews and answered with evidence-based recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. 2) Progressive pulmonary fibrosis (PPF): PPF was defined, and then radiological and physiological criteria for PPF were determined by consensus. Questions about pirfenidone and nintedanib were informed by systematic reviews and answered with evidence-based recommendations using the GRADE approach. Results:1) Update of IPF: A conditional recommendation was made to regard transbronchial lung cryobiopsy as an acceptable alternative to surgical lung biopsy in centers with appropriate expertise. No recommendation was made for or against genomic classifier testing. Conditional recommendations were made against antacid medication and antireflux surgery for the treatment of IPF. 2) PPF: PPF was defined as at least two of three criteria (worsening symptoms, radiological progression, and physiological progression) occurring within the past year with no alternative explanation in a patient with an ILD other than IPF. A conditional recommendation was made for nintedanib, and additional research into pirfenidone was recommended. Conclusions: The conditional recommendations in this guideline are intended to provide the basis for rational, informed decisions by clinicians.

Single-centre experience of transbronchial cryobiopsy as a first choice method for the diagnosis of interstitial lung disease

OBJECTIVES

The diagnosis of interstitial lung disease is based on clinical and biological analysis associated with computed tomography (CT) pattern after discussion in multidisciplinary discussion. Lung transbronchial cryobiopsy has emerged with acceptable diagnostic reliability and low morbidity and mortality. The goal of our work is to describe our experience with lung cryobiopsy.

METHODS

This is monocentric and retrospective analysis of prospectively collected data on epidemiological, clinical, biological, CT, respiratory and histological features of patients with lung transbronchial cryobiopsy between January 1st, 2017, and July 1st, 2020.

RESULTS

Lung transbronchial cryobiopsy has been done for 23 patients with sex ratio M/F of 1.1, majority of smoker/former smoker. Thirty-nine percent of procedures were complicated by pneumothorax. On the haemorrhagic level, we reported 1 grade 2 bleeding (no serious bleeding). An histological diagnosis was obtained for 19 patients (82%). Only 4 patients needed to discuss surgical lung biopsy: 2 (8.6%) surgical lung biopsy, 1 refused surgical lung biopsy and 1 patient lost to follow-up.

CONCLUSION

Our results suggest that transbronchial lung cryobiopsy may be considered the first diagnostic modality instead of surgical lung biopsy for interstitial lung disease in appropriate patients. Larger studies are, however, needed to confirm our observations.

Transbronchial lung cryobiopsy for the diagnosis of interstitial lung diseases

PURPOSE OF REVIEW

Transbronchial lung cryobiopsy has shown promise in several studies in providing meaningful histological information in the multidisciplinary team diagnosis of fibrotic interstitial lung diseases. The purpose of this review is to describe recent literature providing support for the formal integration of cryobiopsy into the algorithm for interstitial lung disease diagnosis.

RECENT FINDINGS

Histopathological concordance between cryobiopsy and surgical biopsy and diagnostic agreement at multidisciplinary discussion have been reported good; furthermore, cryobiopsy may provide an increased diagnostic confidence to a level likely to influence management. Finally, although cryobiopsy is more likely to provide a probable usual interstitial pneumonia (UIP) pattern than a definite UIP pattern, given the limited sampling of sub-pleural lung parenchyma in most cases, finding of a probable UIP pattern at cryobiopsy samples is strongly predictive of a definite UIP pattern in the corresponding surgical biopsy and when a UIP pattern is found on cryobiopsy sample, this is associated with higher mortality compared with other histological patterns.

SUMMARY

Cryobiopsy is becoming a valid alternative to surgical lung biopsy for making histopathological diagnosis in patients with interstitial lung diseases of undetermined type in experienced centres, with standardized protocols, in order to have the best risks/diagnostic yields ratio.

Transbronchial Biopsy and Cryobiopsy in the Diagnosis of Hypersensitivity Pneumonitis among Patients with Interstitial Lung Disease

Rationale: Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) with a diagnosis based on clinical, radiological, and pathological findings. The evidence supporting transbronchial forceps lung biopsy (TBBx) and transbronchial lung cryobiopsy (TBLC) as sampling techniques to diagnose HP in patients with newly detected ILD has not been reviewed systematically.Objectives: A systematic review was performed to assess the diagnostic yield and complication rates of TBBx or TBLC in patients with newly detected ILD whose differential diagnosis includes HP and to inform the development of the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax clinical practice guidelines on the diagnosis of HP.Methods: Medline, Excerpta Medica Database, and the Cochrane Library were searched through October 2019. Studies that enrolled patients with ILD and reported the diagnostic yield of TBBx or TBLC were selected for inclusion. Data related to diagnostic yield and safety outcomes were extracted and then pooled across studies via meta-analysis. The quality of the evidence was appraised using the grading of recommendations, assessment, development, and evaluation (GRADE) approach.Results: The histopathologic diagnostic yields (number of procedures that yielded a histopathologic diagnosis divided by the total number of procedures performed) of TBBx and TBLC were 37% (95% confidence interval [CI], 32-42%) and 82% (95% CI, 78-86%), respectively, among patients with ILD. Among those diagnosed by TBBx, the proportion with HP could not be determined. However, among those diagnosed by TBLC, 13.4% had HP. TBBx was complicated by moderate to severe bleeding, severe bleeding, and pneumothorax in 4% (95% CI, 0-8%), 0% (95% CI, 0-1%), and 7% (95% CI, 2-13%) of patients, respectively. TBLC was complicated by any bleeding, severe bleeding, and pneumothorax in 11% (95% CI, 7-15%), 0% (95% CI, 0-1%), and 11% (95% CI, 9-14%) of patients, respectively. The quality of the evidence was very low because of the uncontrolled study designs, lack of consecutive enrollment, and inconsistent results.Conclusions: Very low-quality evidence indicated that TBLC had a higher diagnostic yield than TBBx among patients with ILD, although complications were similar.

Biopsy in interstitial lung disease: specific diagnosis and the identification of the progressive fibrotic phenotype

PURPOSE OF REVIEW

The evaluation of progression in fibrotic interstitial lung diseases (ILDs) may require a multidimensional approach. This review will cover the role and usefulness of lung biopsy in diagnosis and assessment of the progressive fibrotic phenotype.

RECENT FINDINGS

The identification of specific findings and the balance between inflammation and fibrosis on lung biopsy may help distinguishing different disease entities and may likely determine the effect of treatment and possibly prognosis. The fibrotic morphological patterns potentially associated with a progressive phenotype include usual interstitial pneumonia (UIP), fibrotic nonspecific interstitial pneumonia, pleuroparenchymal fibroelastosis, desquamative interstitial pneumonia, fibrotic hypersensitivity pneumonitis and other less common fibrotic variants, with histopathological findings of UIP at the time of diagnosis being predictive of worse outcome compared with other patterns. The prognostic significance of lung biopsy findings has been assessed after both surgical lung biopsy (SLB) and transbronchial lung cryobiopsy (TBLC), the latter becoming a valid alternative to SLB, if performed in experienced centres, due to significantly lower morbidity and mortality.

SUMMARY

Lung biopsy plays an important role in diagnosis and identification of the progressive fibrotic phenotype. The introduction of less invasive procedures could potentially expand the role of lung sampling, including for example patients with a known diagnosis of ILD or at an earlier stage of the disease.

Endobronchial Balloon Blockers: A Retrospective Analysis of Their Implementation for Use in Transbronchial Cryobiopsy Under Conscious Sedation

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is a promising technique that is evolving as a standard diagnostic procedure in the diagnosis of interstitial lung disease. However, there are a variety of non-standardised techniques adopted for this procedure. We aim to describe our approach to TBLC with balloon blockade under conscious sedation (CS).

METHODS

We performed a retrospective analysis of patients undergoing TBLC using flexible bronchoscopy under CS in our institution over the calendar years 2017-2018; before and after a transition to the use of endobronchial balloon blockers (EBB) in 2017.

RESULTS

25 patients underwent transbronchial cryobiopsy during the study period. Of these; 12 procedures used EBB. EBB subjects had significantly less moderate or severe airway bleeding (8.3% vs 38.5%) despite higher biopsy rates in the EBB group, 2.9 (2-4) vs 2.4 (1-4) in the non-EBB group. No severe airway bleeding occurred in the EBB group. A multidisciplinary meeting (MDM) confirmed diagnosis was achieved in 88% of patients. 10/12 subjects (83%) in the EBB group and 12/13 subjects (92%) in the non-EBB group (p = 0.5).

CONCLUSION

Our institution is novel in using EBB as standard during TBLC specifically under CS with flexible bronchoscopy in the bronchoscopy suite. This retrospective analysis demonstrates that EBB enhances the safety profile of performing TBLC under CS and did not appear to impact diagnostic yield or patient safety.

S2K Guideline for Diagnosis of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a severe and often fatal disease. Diagnosis of IPF requires considerable expertise and experience. Since the publication of the international IPF guideline in the year 2011 and the update 2018 several studies and technical advances have occurred, which made a new assessment of the diagnostic process mandatory. The goal of this guideline is to foster early, confident, and effective diagnosis of IPF. The guideline focusses on the typical clinical context of an IPF patient and provides tools to exclude known causes of interstitial lung disease including standardized questionnaires, serologic testing, and cellular analysis of bronchoalveolar lavage. High-resolution computed tomography remains crucial in the diagnostic workup. If it is necessary to obtain specimens for histology, transbronchial lung cryobiopsy is the primary approach, while surgical lung biopsy is reserved for patients who are fit for it and in whom a bronchoscopic diagnosis did not provide the information needed. After all, IPF is a diagnosis of exclusion and multidisciplinary discussion remains the golden standard of diagnosis.

Ice Capades: Skating Around Current Practice of Cryobiopsy for ILD

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) has been proposed as a potentially safer alternative in the diagnosis of interstitial lung disease. The current practice of TBLC is unknown as most published data come from case reports, case series, and a few trials. The authors report the practice patterns of TBLC on the basis of survey responses.

METHODS

The authors created an anonymous online survey to assess how proceduralists evaluate patients, perform, and manage complications of TBLC. Surveys were distributed through social media and e-mail distribution lists from the American Association of Bronchology and Interventional Pulmonology and the Society of Advanced Bronchoscopists. Aggregated responses are reported as counts, percentages, and averages.

RESULTS

Surveys show significant variation in parameters providers use to assess appropriate patients for procedures, how specific aspects of TBLC are performed, and how complications and results are managed.

CONCLUSION

This is the first and largest survey of providers describing the current large variation in the use of cryobiopsy for the evaluation of interstitial lung disease. The standardized practice is essential to understand the true diagnostic accuracy or rate of complications related to TBLC.

Transbronchial cryobiopsy increases diagnostic confidence in interstitial lung disease: a prospective multicentre trial

INTRODUCTION

The accurate diagnosis of individual interstitial lung diseases (ILD) is often challenging, but is a critical determinant of appropriate management. If a diagnosis cannot be made after multidisciplinary team discussion (MDTD), surgical lung biopsy is the current recommended tissue sampling technique according to the most recent guidelines. Transbronchial lung cryobiopsy (TBLC) has been proposed as an alternative to surgical lung biopsy.

METHODS

This prospective, multicentre, international study analysed the impact of TBLC on the diagnostic assessment of 128 patients with suspected idiopathic interstitial pneumonia by a central MDTD board (two clinicians, two radiologists, two pathologists). The level of confidence for the first-choice diagnoses were evaluated in four steps, as follows: 1) clinicoradiological data alone; 2) addition of bronchoalveolar lavage (BAL) findings; 3) addition of TBLC interpretation; and 4) surgical lung biopsy findings (if available). We evaluated the contribution of TBLC to the formulation of a confident first-choice MDTD diagnosis.

RESULTS

TBLC led to a significant increase in the percentage of cases with confident diagnoses or provisional diagnoses with high confidence (likelihood ≥70%) from 60.2% to 81.2%. In 32 out of 52 patients nondiagnostic after BAL, TBLC provided a diagnosis with a likelihood ≥70%. The percentage of confident diagnoses (likelihood ≥90%) increased from 22.7% after BAL to 53.9% after TBLC. Pneumothoraces occurred in 16.4% of patients, and moderate or severe bleeding in 15.7% of patients. No deaths were observed within 30 days.

INTERPRETATION

TBLC increases diagnostic confidence in the majority of ILD patients with an uncertain noninvasive diagnosis, with manageable side-effects. These data support the integration of TBLC into the diagnostic algorithm for ILD.

The value of virtual bronchoscopic navigation and radial endobronchial ultrasound-guided transbronchial lung cryobiopsies for pulmonary lymphangitic carcinomatosis

Background

Pulmonary lymphangitic carcinomatosis (PLC) is characterized by malignant infiltration into lung lymphatic channels from a primary site and is often observed in advanced malignant tumors. This study aimed to evaluate the diagnostic yield of transbronchial lung cryobiopsy in PLC guided by radial endobronchial ultrasound and virtual bronchoscopic navigation (VBN).

Methods

This prospective study enrolled 40 patients with clinical and radiologic features indicating PLC. The radial endobronchial ultrasound probe was initially advanced to the region of interest of the desired lobe near the pleura with guidance by VBN. Transbronchial lung biopsy and transbronchial lung cryobiopsy were both performed in the same ROI of all patients with the obtained samples being sent to the pathology laboratory for diagnostic analysis. Procedural complications were recorded.

Results

The average number of transbronchial lung biopsy and transbronchial lung cryobiopsy specimens were 4 (3 to 6) and 2 (1 to 3), respectively (t=10.43, P<0.01), with the corresponding mean diameters per biopsy being 3.7 and 8.7 mm (t=12.37, P<0.01). The diagnostic yields of transbronchial lung biopsy and transbronchial lung cryobiopsy were 70% (28/40) and 92.5% (37/40), respectively. The final positive predictive values of transbronchial lung cryobiopsy and transbronchial lung biopsy for PLC were 94.4% (34/36) and 77.8% (28/36), respectively (χ²=23.94, P<0.01). Further, 52.2% (12/23) and 81.5% (22/27) of the patients in the transbronchial lung biopsy and transbronchial lung cryobiopsy groups, respectively, were diagnosed with non-small lung cancer after further molecular analysis (χ²=19.56, P<0.01). Only 2 (5%) cases presented postoperative pneumothorax. Moreover, 0 (0%), 3 (7.5%), and 17 (42.5%) patients presented severe, moderate, and mild bleeding, respectively. There were no other adverse events or deaths.

Conclusions

Transbronchial lung cryobiopsy with the guidance of radial endobronchial ultrasound and VBN without fluoroscopy has a good diagnostic yield for PLC; moreover, it allows one to obtain adequate and intact tissue samples for further molecular analysis.

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. 

Bronchoscopic Cryobiopsy and Forceps Biopsy for the Diagnostic Evaluation of Diffuse Parenchymal Lung Disease in Clinical Practice

Objective

To assess the contribution and safety of bronchoscopic cryobiopsy vs traditional forceps biopsy used in clinical practice for diagnosing diffuse parenchymal lung disease (DPLD).

Patients and Methods

We identified 271 patients who underwent bronchoscopic biopsy for DPLD at Mayo Clinic, MN (June 1, 2013, through September 30, 2017). Medical records were reviewed including prebiopsy clinical and radiographic impressions. Diagnostic yield was assessed in terms of a specific histologic pattern resulting in a diagnosis when combined with the clinical-radiologic context. Clinical utility was defined as a biopsy result deemed useful in patient management.

Results

The cohort included 120 cryobiopsy and 151 forceps biopsy cases with mean age 61±14 years and 143 (53%) men. Diagnostic yield (55% vs 41%; odds ratio [OR], 1.73; 95% CI, 1.07 to 2.83; P=.026) and clinical utility (60% vs 40%; OR, 2.21; 95% CI, 1.36 to 3.63; P=.001) were higher for the cryobiopsy group, and the association remained after control for prebiopsy clinical impressions (OR, 2.21; 95% CI, 1.22 to 4.08; P=.010 and OR, 3.23; 95% CI, 1.76 to 6.10; P<.001, respectively). However, pneumothorax (5.4% vs 0.7%; P=.022) and serious bleeding (7.1% vs 0%; P=.001) rates were higher for the cryobiopsy group. Thirty-day mortality was 1.6% in the cryobiopsy group vs 0% for the forceps biopsy group (P=.20).

Conclusion

Bronchoscopic cryobiopsy revealed higher diagnostic yield and clinical utility than did forceps biopsy. However, procedure-related complications were higher in the cryobiopsy group. The choice of bronchoscopic biopsy procedure for patients with DPLD depends on the clinicalradiologic context.

Diagnosis of Hypersensitivity Pneumonitis in Adults. An Official ATS/JRS/ALAT Clinical Practice Guideline

Background: This guideline addresses the diagnosis of hypersensitivity pneumonitis (HP). It represents a collaborative effort among the American Thoracic Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax.Methods: Systematic reviews were performed for six questions. The evidence was discussed, and then recommendations were formulated by a multidisciplinary committee of experts in the field of interstitial lung disease and HP using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.Results: The guideline committee defined HP, and clinical, radiographic, and pathological features were described. HP was classified into nonfibrotic and fibrotic phenotypes. There was limited evidence that was directly applicable to all questions. The need for a thorough history and a validated questionnaire to identify potential exposures was agreed on. Serum IgG testing against potential antigens associated with HP was suggested to identify potential exposures. For patients with nonfibrotic HP, a recommendation was made in favor of obtaining bronchoalveolar lavage (BAL) fluid for lymphocyte cellular analysis, and suggestions for transbronchial lung biopsy and surgical lung biopsy were also made. For patients with fibrotic HP, suggestions were made in favor of obtaining BAL for lymphocyte cellular analysis, transbronchial lung cryobiopsy, and surgical lung biopsy. Diagnostic criteria were established, and a diagnostic algorithm was created by expert consensus. Knowledge gaps were identified as future research directions.Conclusions: The guideline committee developed a systematic approach to the diagnosis of HP. The approach should be reevaluated as new evidence accumulates.

Management of interstitial lung diseases: A consensus statement of the Indian Chest Society (ICS) and National College of Chest Physicians (NCCP)

BACKGROUND

Interstitial lung disease (ILD) is a complex and heterogeneous group of acute and chronic lung diseases of several known and unknown causes. While clinical practice guidelines (CPG) for idiopathic pulmonary fibrosis (IPF) have been recently updated, CPG for ILD other than IPF are needed.

METHODS

A working group of multidisciplinary clinicians familiar with clinical management of ILD (pulmonologists, radiologist, pathologist, and rheumatologist) and three epidemiologists selected by the leaderships of Indian Chest Society and National College of Chest Physicians, India, posed questions to address the clinically relevant situation. A systematic search was performed on PubMed, Embase, and Cochrane databases. A modified GRADE approach was used to grade the evidence. The working group discussed the evidence and reached a consensus of opinions for each question following face-to-face discussions.

RESULTS

Statements have been made for each specific question and the grade of evidence has been provided after performing a systematic review of literature. For most of the questions addressed, the available evidence was insufficient and of low to very low quality. The consensus of the opinions of the working group has been presented as statements for the questions and not as an evidence-based CPG for the management of ILD.

CONCLUSION

This document provides the guidelines made by consensus of opinions among experts following discussion of systematic review of evidence pertaining to the specific questions for management of ILD other than IPF. It is hoped that this document will help the clinician understand the accumulated evidence and help better management of idiopathic and nonidiopathic interstitial pneumonias.

Diagnosis of Idiopathic Pulmonary Fibrosis. An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline

BACKGROUND

This document provides clinical recommendations for the diagnosis of idiopathic pulmonary fibrosis (IPF). It represents a collaborative effort between the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society.

METHODS

The evidence syntheses were discussed and recommendations formulated by a multidisciplinary committee of IPF experts. The evidence was appraised and recommendations were formulated, written, and graded using the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

The guideline panel updated the diagnostic criteria for IPF. Previously defined patterns of usual interstitial pneumonia (UIP) were refined to patterns of UIP, probable UIP, indeterminate, and alternate diagnosis. For patients with newly detected interstitial lung disease (ILD) who have a high-resolution computed tomography scan pattern of probable UIP, indeterminate, or an alternative diagnosis, conditional recommendations were made for performing BAL and surgical lung biopsy; because of lack of evidence, no recommendation was made for or against performing transbronchial lung biopsy or lung cryobiopsy. In contrast, for patients with newly detected ILD who have a high-resolution computed tomography scan pattern of UIP, strong recommendations were made against performing surgical lung biopsy, transbronchial lung biopsy, and lung cryobiopsy, and a conditional recommendation was made against performing BAL. Additional recommendations included a conditional recommendation for multidisciplinary discussion and a strong recommendation against measurement of serum biomarkers for the sole purpose of distinguishing IPF from other ILDs.

CONCLUSIONS

The guideline panel provided recommendations related to the diagnosis of IPF.

Transbronchial Lung Cryobiopsy in Idiopathic Pulmonary Fibrosis: A State of the Art Review

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease associated with significant morbidity and mortality. The diagnosis of IPF involves a combination of clinical history, radiological imaging and examination of histopathological samples in appropriate cases. Historically, transbronchial biopsy (TBB) has been used to obtain histological samples; however this lacks diagnostic accuracy. At present, surgical lung biopsy (SLB) is the gold standard technique for obtaining specimen samples; however this carries a significant mortality risk. Transbronchial lung cryobiopsy (TBLC) is a new technique that has been pioneered in the management of lung malignancy and offers a potential alternative to SLB. The technique employs a freezing probe, which is used to obtain lung tissue samples that are larger and better quality than traditional TBB samples. This affords TBLC an estimated diagnostic yield of 80% in interstitial lung disease. However, with limited evidence directly comparing TBLC to SLB, the diagnostic accuracy of the procedure has been uncertain. Common complications of TBLC include pneumothorax and bleeding. Mortality in TBLC is low compared with SLB, with exacerbation of IPF frequently reported as the cause. TBLC represents an exciting potential option in the diagnostic pathway in IPF; however its true value has yet to be determined.

Management and utility of transbronchial lung cryobiopsy in Japan

BACKGROUND

Transbronchial lung cryobiopsy (TBLC), which is transbronchial lung biopsy performed using a cryoprobe, has emerged as a new method for obtaining lung tissue specimens for diagnosing pulmonary diseases. TBLC has been widely performed, and many reports have documented its safety and feasibility in diagnosing pulmonary diseases such as lung cancer and diffuse parenchymal lung disease. However, to date, no reports have yet been published from Japan. Therefore, the purpose of this study was to describe our experience with TBLC in daily practice in Japan and compare it with those reported in previous studies from other countries. We also evaluated the efficacy and feasibility of TBLC.

METHODS

We retrospectively evaluated the clinical records of 50 consecutive patients who had undergone TBLC between November 2017 and May 2018 at the Japanese Red Cross Medical Center. Demographic data, procedure details, and the diagnostic yield were analyzed.

RESULTS

We analyzed the records of 50 patients who underwent diagnostic TBLC. Their median age was 71 years, and they included 34 men (68%). The median maximal diameter of the cryobiopsy specimens was 5.3 mm (range, 2.0-23.0 mm), and the median area of the cryobiopsy specimens was 15.5 mm² (range, 3.0-136.5 mm²). The rate of obtaining adequate specimens was 91%, and the pathological diagnostic yield was 76%. No complications were observed, except for one case of pneumonia.

CONCLUSIONS

This is the first report from Japan analyzing the efficacy and feasibility of TBLC in daily clinical practice. TBLC was considered efficacious, safe, and feasible for Japanese patients with various lung diseases.

Bronchoscopic lung cryobiopsy: An Indian association for bronchology position statement

BACKGROUND

Bronchoscopic lung cryobiopsy (BLC) is a novel technique for obtaining lung tissue for the diagnosis of diffuse parenchymal lung diseases. The procedure is performed using several different variations of technique, resulting in an inconsistent diagnostic yield and a variable risk of complications. There is an unmet need for standardization of the technical aspects of BLC.

METHODOLOGY

This is a position statement framed by a group comprising experts from the fields of pulmonary medicine, thoracic surgery, pathology, and radiology under the aegis of the Indian Association for Bronchology. Sixteen questions on various technical aspects of BLC were framed. A literature search was conducted using PubMed and EMBASE databases. The expert group discussed the available evidence relevant to each question through e-mail and a face-to-face meeting, and arrived at a consensus.

RESULTS

The experts agreed that patients should be carefully selected for BLC after weighing the risks and benefits of the procedure. Where appropriate, consideration should be given to perform alternate procedures such as conventional transbronchial biopsy or subject the patient directly to a surgical lung biopsy. The procedure is best performed after placement of an artificial airway under sedation/general anesthesia. Fluoroscopic guidance and occlusion balloon should be utilized for positioning the cryoprobe to reduce the risk of pneumothorax and bleeding, respectively. At least four tissue specimens (with at least two of adequate size, i.e., ≥5 mm) should be obtained during the procedure from different lobes or different segments of a lobe. The histopathological findings of BLC should be interpreted by an experienced pulmonary pathologist. The final diagnosis should be made after a multidisciplinary discussion. Finally, there is a need for structured training for performing BLC.

CONCLUSION

This position statement is an attempt to provide practical recommendations for the performance of BLC in DPLDs.

The value of using radial endobronchial ultrasound to guide transbronchial lung cryobiopsy

Conventional transbronchial biopsies have a low diagnostic yield for interstitial lung disease (ILD) and peripheral lung nodules due to crush artifact and smaller tissue samples. Transbronchial lung cryobiopsies (TBLC) circumvent these drawbacks but are associated with higher incidence of complications including life threatening airway bleeding and pneumothoraces. Radial probe endobronchial ultrasound (RP-EBUS) can be used during the TBLC for assessing the biopsy site prior to the cryobiopsy to avoid vasculature and to decrease the risk of complications. There is no standardized protocol for this technique and the available literature mostly consists of single center case reports/series. The aim of this review is to investigate the existing literature for RP-EBUS assisted TBLC for diagnosing both ILD and peripheral lung nodules. We will describe the techniques used and compare the diagnostic yield and complication rates with other modalities.

The safety and efficacy of different methods for obtaining transbronchial lung cryobiopsy in diffuse lung diseases

INTRODUCTION

Most data on transbronchial lung cryobiopsy (TBLC) are from single centers, with little evidence on the outcome of different methods for performing TBLC.

OBJECTIVE

To report the diagnostic yield and safety of TBLC with different procedural techniques.

MATERIALS AND METHODS

Retrospective multicenter study of subjects who underwent TBLC for the diagnosis of diffuse parenchymal lung diseases (DPLDs). The procedure was performed using various methods: flexible or rigid bronchoscopy, with or without the use of fluoroscopy or occlusion balloon.

RESULTS

In total, 128 subjects (59% women) with a mean age of 48.9 years were included. The overall diagnostic yield of TBLC was 78.1%, with a definite diagnosis on multidisciplinary discussion made in 57 (44.5%) subjects. On a multivariate analysis, the diagnostic yield was associated with the number of biopsies taken {ajdusted odds ratio [AOR] [95% confidence interval (CI)], 2.17 [1.29-3.67]}. The incidence of pneumothorax was lower in subjects who underwent TBLC with fluoroscopic guidance (5.9% vs 20.9%), [AOR (95% CI), 0.26 (0.07-0.94)]. Moderate-to-severe bleeding occurred less frequently when an occlusion balloon was used [1.8% vs 35.7%; AOR (95% CI), 0.02 (0.001-0.18)], after adjusting for age, use of fluoroscopy, number of biopsies obtained and number of lobes sampled. Four deaths occurred; 2 because of acute exacerbation of idiopathic pulmonary fibrosis.

CONCLUSIONS

Transbronchial lung cryobiopsy was found to offer a reasonable yield in the diagnosis of DPLDs. The incidence of pneumothorax and moderate-to-severe bleeding was lower with the use of fluoroscopy and an occlusion balloon, respectively.

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.

Use of transbronchial cryobiopsy in the diagnosis of interstitial lung disease-a systematic review and cost analysis

BACKGROUND

Histological diagnosis by surgical lung biopsy for interstitial lung disease (ILD) is currently limited. Transbronchial cryobiopsy via flexible bronchoscope may this for more patients. The relative costs, diagnostic yields and safety of this approach and more traditional approaches have not been determined.

OBJECTIVES

To perform a systematic review and meta-analysis of transbronchial cryobiopsy, forceps transbronchial biopsy and video assisted (VATS) surgical lung biopsy assessing their relative diagnostic yields and safety. To perform a cost analysis to demonstrate any savings through change to the newer technique.

METHODS

We performed a systematic review of the literature using MEDLINE and EMBASE for all original articles on the diagnostic yield and safety of transbronchial cryobiopsy, forceps transbronchial biopsy and VATS-biopsy in ILD up to February 2016. Data were extracted on yield and complication rates, in addition to study characteristics. Theoretical cost analysis was performed from local institution financial data, 2015-16 reimbursement tariffs and results of the systematic review.

RESULTS

A meta-analysis of 11 investigations for transbronchial cryobiopsy, 11 for forceps transbronchial biopsy and 24 for VATS-biopsy revealed diagnostic yields of 84.4% (75.9-91.4%), 64.3% (52.6-75.1%) and 91.1% (84.9-95.7%), respectively. Pneumothorax occurred in 10% (5.4-16.1%) of transbronchial cryobiopsy procedures, moderate bleeding in 20.99% (5.6-42.8%), with three deaths reported. Surgical mortality was 2.3% (1.3-3.6%). Cost analysis demonstrated potential savings of £210 per patient in the first year and £647 in subsequent years.

CONCLUSIONS

Transbronchial cryobiopsy represents a potentially cost-saving approach to improve histological diagnosis in ILD, however is accompanied by a significant risk of moderate bleeding.

Pneumonic-type mucinous lung adenocarcinoma diagnosed by transbronchial cryobiopsy

Primary lung adenocarcinoma with lepidic growth can mimic diffuse pulmonary parenchymal processes like infectious pneumonia or idiopathic inflammatory pneumonitis. We report a case of subacute pneumonitis refractory to antibiotic therapy and empirical corticosteroids, proven to be diffuse mucinous adenocarcinoma with lepidic growth on transbronchial cryobiopsy.