Transbronchial lung cryobiopsy: prospective safety evaluation and 90-day mortality after a standardized examination protocol

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) is a new method of bronchoscopic tissue sampling in patients with unclear diffuse parenchymal lung disease (DPLD). While not the gold standard, TBLC has a good diagnostic correlation with surgical lung biopsy, and retrospective analyses of peri-interventional complications and mortality are promising. However, prospective reports on 90-day mortality are lacking.

OBJECTIVES

This study addresses morbidity and 30- and 90-day mortality in TBLC after a standardized protocol.

METHODS

In this prospective study, 75 patients with DPLD requiring tissue sampling were included. A standardized protocol (including prophylactic use of an endobronchial balloon, postinterventional observation, and minimum sampling requirements) was used in all patients. Adverse events (pneumothorax, bronchial bleeding, premature discontinuation, prolonged monitoring at ICU, and fatal outcome) and 30- and 90-day mortality rates were recorded.

RESULTS

A total of 308 cryobiopsies were performed in 75 patients. Peri- and postinterventional pneumothorax were observed in 20% (9.3% mild and 10.7% moderate with the necessity of chest drainage), and bronchial bleeding was found in 29.3% (22.7% moderate and 6.7% severe). Total lung capacity below normal value was associated with the risk of pneumothorax (p = 0.009), and diffusion limitation for carbon monoxide below normal value was associated with the risk of bronchial bleeding (p = 0.044). No fatal events were observed within 30 days, and the 90-day mortality rate was 1.3%, but not related to the procedure itself.

CONCLUSION

As it gradually becomes the invasive procedure of choice in unclear DPLD, TBLC is a safe procedure with a low 30- and 90-day mortality.Trial registration ID: DRKS00026746 (German Clinical Trial Register).

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.

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.

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.

Utility of Flexible Bronchoscopic Cryobiopsy for Diagnosis of Diffuse Parenchymal Lung Diseases

BACKGROUND

Initial reports of transbronchial cryobiopsy for diffuse parenchymal lung disease (DPLD) suggest the diagnostic yield approaches that of surgical lung biopsy (SLB) with an excellent safety profile. Centers performing cryobiopsy differ significantly in procedure technique; an optimal technique minimizing complications but still capable of diagnosing a wide range of DPLDs has not been established. We evaluated our practice of flexible bronchoscopic cryobiopsy in a primarily outpatient setting for patients who required a tissue diagnosis for DPLD of uncertain etiology.

METHODS

Consecutive patients with indeterminate DPLD who underwent bronchoscopic cryobiopsy at a large academic medical center from January 2012 to August 2015 were retrospectively analyzed. Rates of confident histopathologic diagnosis, confident multidisciplinary consensus diagnosis, management change, and complications were determined.

RESULTS

One hundred four cases were identified. Confident histopathologic diagnoses were established in 44% (46/104) and confident multidisciplinary consensus diagnoses in 68% (71/104). Usual interstitial pneumonia (19/104) and idiopathic pulmonary fibrosis (22/104) were the most common histopathologic and consensus diagnoses, respectively. Five subjects proceeded to SLB after cryobiopsy which was diagnostic in 3. Results of cryobiopsies changed management in 70% (73/104). Complications occurred in 8 cases with no death.

CONCLUSIONS

Cryobiopsy during outpatient flexible bronchoscopy facilitated confident multidisciplinary consensus diagnosis of DPLD in more than two thirds of cases, and appears sufficient to establish the histopathologic diagnosis of usual interstitial pneumonia, with a complication rate that compares favorably to that reported for SLB.

Effect evaluation on use of bedside fiber bronchoscope in treating stroke-associated pneumonia

Background The bedside fiber bronchoscope has been widely used in the diagnosis and treatment of respiratory disease. This study aims to assess the effect of using bedside fiber bronchoscope in sputum suction and alveolar lavage for treatment of stroke-associated pneumonia (SAP), compared with the use of conventional suction catheter. Methods One hundred and six patients with SAP were randomly divided into control group (n = 53) and experimental group (n = 53) for a controlled study. Patients in the two groups were conventionally treated with phlegm-resolving and anti-infective therapy. The conventional suction catheter was used for sputum suction for patients in the control group, while bedside fiber bronchoscope was used for sputum suction and alveolar lavage in the experimental group. Clinical pulmonary infection score (CPIS) of the two groups was carried out. The heart rate, blood gas, levels of inflammatory factors in serum, and CPIS were contrastively analyzed between the two groups. Results The blood gas (including pH, PaCO₂, PaO₂) levels of inflammatory factors in serum such as C-reactive protein, procalcitonin, interleukin-6 and tumor necrosis factor, and CPIS (including the third day and seventh day) in the experimental group (n = 53) were all superior to those of the control group (n = 53) (p < 0.05). The results suggested that the pulmonary ventilation condition and inflammatory response of patients with SAP were significantly improved with the use of bedside fiber bronchoscope. Conclusion The use of bedside fiber bronchoscope is beneficial in modifying the pulmonary ventilation and relieving systemic inflammatory response of patients with SAP, exhibiting a great value in clinical application.

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.

Transbronchial Cryobiopsy in Diffuse Parenchymal Lung Disease: Retrospective Analysis of 74 Cases

BACKGROUND

Diagnostic evaluation of patients with diffuse parenchymal lung disease (DPLD) is best achieved by a multidisciplinary team correlating clinical, radiological, and pathologic features. Surgical lung biopsy remains the gold standard for histopathologic diagnosis of idiopathic interstitial pneumonias. Emerging data suggest an increasing role for transbronchial cryobiopsy (TBC) in DPLD evaluation. We describe our experience with TBC in patients with DPLD.

METHODS

We retrospectively reviewed medical records of patients with radiographic features of DPLD who underwent TBC at Mayo Clinic in Rochester, Minnesota from June 2013 to September 2015.

RESULTS

Seventy-four patients (33 women [45%]) with a mean age of 63 years (SD, 13.8) were included. The mean maximal diameter of the samples was 9.2 mm (range, 2-20 mm [SD, 3.9]). The median number of samples per procedure was three (range, one to seven). Diagnostic yield was 51% (38 of 74 specimens). The most frequent histopathologic patterns were granulomatous inflammation (12 patients) and organizing pneumonia (OP) (11 patients), resulting in the final diagnoses of hypersensitivity pneumonitis (six patients), cryptogenic OP (six patients), connective tissue disease-associated OP (three patients), drug toxicity (three patients), infection-related OP (two patients), sarcoidosis (two patients), and aspiration (one patient). Other histopathologic patterns included respiratory bronchiolitis (three patients), acute fibrinous and organizing pneumonia (two patients), desquamative interstitial pneumonia (1 patient), diffuse alveolar damage (one patient), pulmonary alveolar proteinosis (one patient), amyloidosis (one patient), eosinophilic pneumonia (one patient), necrotizing vasculitis (one patient), bronchiolitis with food particles (one patient), and malignancy (three patients). Pneumothorax developed in one patient (1.4%), and bleeding occurred in 16 patients (22%).

CONCLUSIONS

Our single-center cohort demonstrated a 51% diagnostic yield from TBC; the rates of pneumothorax and bleeding were 1.4% and 22%, respectively. The optimal use of TBC needs to be determined.

Efficacy and safety of cryobiopsy versus forceps biopsy for interstitial lung diseases and lung tumours: A systematic review and meta-analysis

Forceps biopsy (FB) is the most commonly used diagnostic tool for lung pathologies. FB is associated with a high diagnostic failure rate. Cryobiopsy (CB) is a novel technique providing a larger specimen size, few artefacts, more alveolar parts and superior diagnostic yield. CB, however, has drawbacks such as higher bleeding and pneumothorax rate. We conducted a meta-analysis to investigate the specimen area, diagnostic rate and bleeding severity in CB versus FB in interstitial lung diseases (ILDs) and lung tumours. A systematic literature search of PUBMED, BIOSIS PREVIEW and OVID databases was conducted using specific search terms. Eligible studies including RCTs and non-RCTs comparing cryobiopsy/cryotransbronchial biopsy (CB/CTBB) and forceps biopsy/forceps transbronchial biopsy (FB/FTBB) for specimen area, diagnostic rate and bleeding rate in ILDs and lung tumours were analysed. Two reviewers independently extracted data and evaluated the quality of the studies. Eight studies involving 916 patients were analysed. Specimen area (mm(2) ) was significantly larger in CB/CTBB than FB/FTBB (standard mean difference = 1.21, 95% confidence interval (0.94, 1.48), P < 0.00001). The diagnostic rate was significantly higher in CB/CTBB than FB/FTBB (Risk ratio 1.36, 95% confidence interval (1.16, 1.59), P = 0.0002). Three studies compared the bleeding severity with only one showing significantly more bleeding in CB. Cryobiopsy/cryotransbronchial shows superiority to FB/FTBB for specimen area and diagnostic rate. CB/CTBB has better efficacy over FB/FTBB.

Transbronchial Cryobiopsies in the Evaluation of Lung Allografts: Do the Benefits Outweigh the Risks?

CONTEXT

Transbronchial cryobiopsy technique yields larger biopsies with enhanced quality. The benefits and safety of cryobiopsies have not been thoroughly studied in lung allografts.

OBJECTIVE

To compare size, quality, reproducibility of interpretation of rejection and complications of cryobiopsies with those of conventional biopsies from lung allografts.

DESIGN

All cryobiopsies (March 2014-January 2015) of lung allografts performed at Mayo Clinic, Rochester, and medical records were reviewed. For comparison, conventional biopsies from the same patient or, if unavailable, from a random patient, were selected. Two pathologists blinded to outcome reviewed all biopsies. Specimen volume, number of alveoli, small airways, and pulmonary vessels were counted and statistically compared.

RESULTS

Fifty-four biopsies (27 cryobiopsies) from 18 patients (11 men) were reviewed. A median of 3 (range, 2-5) and 10 (range, 6-12) specimens were obtained with cryobiopsies and conventional biopsies, respectively. Cryobiopsies were larger and contained more alveoli (P < .001, both) and small airways (P = .04). Conventional biopsies showed more fresh alveolar hemorrhage (procedural) and crush artifact/atelectasis (P < .001, both). Cryobiopsies contained more pulmonary veins and venules (P < .001). There was no significant difference between the types of biopsies with respect to the reviewers' agreement on grades of rejection. Complications were more frequent in the cryobiopsy group, though the difference was not statistically significant.

CONCLUSIONS

Cryobiopsies of lung allografts are larger and have less artifact. However, complications occur and should be considered. Three cryobiopsy specimens appear sufficient for histopathologic evaluation of lung allografts.