Transbronchial cryobiopsy in immunocompromised patients with pulmonary infiltrates: a pilot study

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.

Transbronchial Cryobiopsy Compared to Forceps Biopsy for Diagnosis of Acute Cellular Rejection in Lung Transplants: Analysis of 63 Consecutive Procedures

Background: Acute cellular rejection (ACR) is a complication after lung transplantation (LTx). The diagnosis of ACR is based on histologic findings using transbronchial forceps biopsy (FB). However, its diagnostic accuracy is limited because of the small biopsy size and crush artifacts. Transbronchial cryobiopsy (CB) provides a larger tissue size compared with FB. Methods: FB and CB were obtained consecutively during the same bronchoscopy (February 2020–April 2021). All biopsies were scored according to the ISHLT criteria by three pathologists. Interobserver agreement was scored by the kappa index. We assessed the severity of bleeding and the presence of pneumothorax. Results: In total, 35 lung transplant recipients were included, and 126 CBs and 315 FBs were performed in 63 consecutive bronchoscopies. ACR (A1–A3, minimal–moderate) was detected in 18 cases (28.6%) by CB, whereas ACR was detected in 3 cases (4.8%) by FB. Moderate and severe bleeding complicated FB and CB procedures in 23 cases (36.5%) and 1 case (1.6%), respectively. Pneumothorax occurred in 6.3% of patients. The interobserver agreement was comparable for both CB and FB. Conclusions: CB provided an improved diagnostic yield for ACR diagnosis, leading to reclassification and changes in treatment strategies in 28.6% of cases. Prospective studies should better define the role of CB after LTx.

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.

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.

Lung Cryobiopsy Outside of the Operating Room: A Safe Alternative to Surgical Biopsy

Objective

Transbronchial lung cryobiopsy (TBLC) is a promising technique that can provide a histologic diagnosis in interstitial lung diseases (ILD) and is an alternative to surgical lung biopsy. The main concerns with the procedure are safety and diagnostic accuracy. The technique is applicable in patients unable to undergo surgical biopsy due to severe comorbidities or when patient transport to the operating room is dangerous. This study reports the initial experience with TBLC on a thoracic surgical service as a first attempt at diagnosis in patients with diffuse parenchymal lung diseases (DPLD).

Methods

Between May 2018 and July 2020, 32 patients underwent TBLC using bedside flexible bronchoscopy for suspected ILD on a thoracic surgical endoscopy service. Retrospective evaluation of the procedure details, complications, and diagnostic yield were analyzed and reported.

Results

A total of 89 pathological samples were obtained (mean 2.8 per patient). Pneumothorax and minor bleeding occurred in 25% and 16.7% of patients, respectively. Sixty-seven percent of complications occurred with use of the 2.4 mm cryoprobe (P = 0.036). Concordance between the histologic diagnosis and final clinical diagnosis was observed in 62.5% of patients and the pathology guided the final treatment in 71% (P = 0.027) with Kappa-concordance of 0.60 (P < 0.001).

Conclusions

Cryobiopsy is becoming part of the diagnostic evaluation in patients with indeterminate DPLD or hypoxemic respiratory failure. TBLC is easy to perform and has a favorable safety profile. Thoracic specialists should consider adding TBLC to their procedural armamentarium as a first option for patients with indeterminate PLD.

Applied pressure of cooling gas: a neglected determinant for size of specimens in transbronchial cryobiopsy

Background

Transbronchial cryobiopsy (TBCB) is an option to surgical biopsy for the diagnosis in interstitial lung diseases. Several impact factors have received wide attention, including the freezing time, cryoprobe size, and contact pressure. However, the effect of the applied gas pressure on the specimen size has not been well elucidated. The purpose of this study is to investigate the effect of the applied gas pressure on the TBCB specimen size.

Methods

Cryoprobes with a diameter of 1.9 mm were used to perform TBCB on 4 beagle canines under general anesthesia. TBCB was performed with a total of 16 time-pressure combinations that were randomly combined with 4 freezing times (3, 4, 5, and 6 s) and 4 gas pressures (40, 50, 55, and 60 bar). For each combination, 8 biopsies were performed. The size and quality of specimens, as well as complications, were evaluated.

Results

A total of 128 TBCB specimens were obtained. With the same freezing time, the specimen sizes obtained by different applied gas pressures were significantly different (P<0.05) and positively correlated with the gas pressures (r: 0.797–0.867). With the same gas pressure, the size of the TBCB specimens was positively correlated with the freezing time (r: 0.503–0.752). In the 40-bar group, no tissues were obtained when the freezing times were 3–5 s. In the 50-bar and 55-bar groups, qualified specimens were obtained when the freezing times were 5 and 6 s. In the 60-bar group, qualified specimens were obtained when the freezing times were 3–6 s.

Conclusions

The TBCB specimen size was positively correlated with the applied gas pressure. The applied gas pressure contributed to the sample size and quality. To obtain qualified specimens with a 1.9-mm cryoprobe during TBCB, the lowest limit of the normal working gas pressure range should be increased to greater than 50 bar.

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.

Transbronchial Cryobiopsy in the Diagnosis of Diffuse Lung Disease

Transbronchial cryobiopsy, a new diagnostic procedure in patients with diffuse lung disease, provides larger and better-preserved lung specimens compared to forceps biopsy. The diagnostic yield of cryobiopsy is much better than that of forceps biopsy and slightly lower than that of surgical lung biopsy, but with a lower complication rate compared to the latter. Literature suggests that in the multidisciplinary approach to patients with diffuse lung disease cryobiopsy provides diagnostic and prognostic information similar to surgical lung biopsy. Cryobiopsy can also be performed in some patients unsuitable for surgical biopsy, yet in whom histologic input is needed.

Evaluation of Efficacy of a New Cryoprobe for Transbronchial Cryobiopsy: A Randomized, Controlled in vivo Animal Study

BACKGROUND

Forceps biopsy (FB) is still the most popular procedure for the bronchoscopic sampling of lung tissue. However, it has limitations like inadequate sample size and crush artifacts. Cryobiopsy (CB) has been introduced to obtain bronchoscopic biopsies with improved diagnostic yield compared to FB. Limitations of CB are the need to retract the cryoprobe en bloc with bronchoscope because samples are larger than the working channel and the variations of the freezing power of the reusable CB (rCB). Therefore, 3 new disposable cryoprobes (dCB) have been developed with different outer diameters: 1.1 mm (CB11-S) that can be retracted through the working channel of the bronchoscope, 1.7 mm (CB17) and 2.4 mm (CB24n), respectively.

OBJECTIVES

The aim was to evaluate the new cryoprobes with regard to feasibility, specimen area, specimen quality and complications.

METHODS

We compared biopsy samples of the new probes with those obtained by FB and by rCB in an in vivo (porcine) model. A flexible bronchoscope was used to perform biopsy at 4 different locations at the upper and lower lobes of the right and left lung, respectively. The biopsies were taken under fluoroscopic control. The biopsy tool and activation times were allocated randomly. Altogether 204 biopsy procedures were performed.

RESULTS

The sample quality of the dCB was superior to that of FB (all p < 0.05) and not significantly different to the rCB sample quality. Mean specimen sample area of all CB was significantly larger compared to FB (p < 0.05). The sample area of the small cryoprobe (CB11-S) was significantly smaller compared to the other CB probes (p < 0.05). No severe bleedings occurred. Pneumothoraces were detected in 3 of the 7 pigs.

CONCLUSION

We conclude that CB with the new single-use instruments are feasible and represent a viable option to improve the diagnostic accuracy of histopathological evaluation compared to FB.

Optimization of Transbronchial Cryobiopsy in Lung Transplant Recipients

BACKGROUND

Previous studies suggest that transbronchial lung biopsy using a cryoprobe is superior to transbronchial lung biopsy using forceps for evaluating lung grafts, although the technique can be associated an increase in complications. Because cryoprobe experience is limited, assessment of a greater number of cases is warranted. This prospective study evaluates the diagnostic yield, complications, and risk factors associated with the cryoprobe technique.

METHODS

From April 2013 to April 2016, 321 consecutive cryoprobe transbronchial biopsies were indicated in single or bilateral lung transplant patients with acute or chronic clinical lung injury or in asymptomatic patients before hospital discharge after lung transplantation.

RESULTS

With a mean of 4.32 lung parenchyma specimens per procedure, adequate alveolar lung parenchyma was obtained in 96.6% (84.27 ± 44.14 mm²) of cases. Obtaining at least 4 samples increased the histological diagnostic certainty (P < .001). Moderate to severe bleeding was observed in 7.48% of patients and was significantly more frequent in patients with unilateral transplantation (odds ratio, 0.10; 95% confidence interval, 0.02-0.30; P < .001) and in those with high blood pressure during scanning (odds ratio, 0.31; 95% confidence interval, 0.12-0.86; P = .019). Pneumothorax was observed in 7.7% of the patients, but only 3.7% of these patients required pleural drainage.

CONCLUSIONS

Obtaining 4 or more cryobiopsy samples is valuable and safe for lung allograft monitoring. Being a recipient of a unilateral lung transplant or having arterial hypertension during bronchoscopy seem to be risk factors associated with increased bleeding.

Cryoprobe biopsy for the diagnosis of acute hypoxemic respiratory failure of undetermined origin

Rationale

Acute hypoxemic respiratory failure is a condition that comprises a wide array of entities. Obtaining a histological lung sample might help reach a diagnosis and direct an appropriate treatment in a select group of patients.

Objective

To describe our experience in the use of cryobiopsy for the diagnosis of acute hypoxemic respiratory failure of undetermined origin.

Methods

Retrospective analysis of case series of patients with acute hypoxemic respiratory failure who underwent lung cryobiopsy at the Intensive Care Unit of the Hospital Italiano de Buenos Aires, Argentina.

Results

Cryobiopsy yielded a histological diagnosis in all patients (n = 10, 100%). This led to either a change in therapy or continuation of a specific treatment in eight of these patients. Cryobiopsy was found to be contributive in all the patients who did not meet Berlin criteria for acute respiratory distress syndrome. No major complications were associated with the procedure.

Conclusions

Cryobiopsy is a safe procedure with a high diagnostic yield in a selected group of patients.

Persistent focal pulmonary opacity elucidated by transbronchial cryobiopsy: a case for larger biopsies

Persistent pulmonary opacities associated with respiratory symptoms that progress despite medical treatment present a diagnostic dilemma for pulmonologists. We describe the case of a 37-year-old woman presenting with progressive fatigue, shortness of breath, and weight loss over six months with a progressively worsening right basilar infiltrate on chest imaging in spite of antibacterial therapy. Transbronchial cryobiopsy was used to establish the diagnosis after a bronchoscopy with traditional forceps biopsies was non-diagnostic. This case demonstrates the value of cryobiopsy as a second-line strategy for pulmonary infiltrates when aetiology remains unclear after less invasive testing.

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.

Idiopathic pulmonary fibrosis: prognostic impact of histologic honeycombing in transbronchial lung cryobiopsy

Background

Prognostic evaluation in idiopathic pulmonary fibrosis (IPF) may be important as it can guide management decisions, but the potential role of honeycomb changes in providing information about outcome and survival of patients with IPF, particularly if diagnosed using cryobiopsy, has not been evaluated. Aim of this study was to determinate whether a relationship exists between honeycombing on cryobiopsy and clinical/radiological picture and outcome in patients with IPF and to assess whether the same pathologic criteria that have been used to define the UIP pattern (usual interstitial pneumonia) for surgical biopsy can also be applied to cryobiopsy.

Methods

Sixty-three subjects with a multidisciplinary diagnosis of IPF and a UIP pattern on cryobiopsy were evaluated. Patients were classified into two sub-groups depending on the presence of honeycombing on histology.

Results

The presence of honeycombing on cryobiopsy did not identify a specific phenotype of patients as it did not correlate with radiological and clinical picture and it was not associated neither with the risk of death (p = 0.1192) or with the event-free survival (p = 0.827); a higher number of samples and the presence of pleura on biopsy were instead associated with an increase in the finding of honeycombing.

Conclusions

The same pathologic criteria that have been used to define the UIP pattern in surgical biopsies (with honeycombing changes considered as non-mandatory for the definition of the pattern itself) can be applied to cryobiopsy samples, as the presence of these changes do not define different clinical or radiological phenotypes of patients with IPF.

Acute respiratory failure in immunocompromised adults

Acute respiratory failure occurs in up to half of patients with haematological malignancies and 15% of those with solid tumours or solid organ transplantation. Mortality remains high. Factors associated with mortality include a need for invasive mechanical ventilation, organ dysfunction, older age, frailty or poor performance status, delayed intensive care unit admission, and acute respiratory failure due to an invasive fungal infection or unknown cause. In addition to appropriate antibacterial therapy, initial clinical management aims to restore oxygenation and predict the most probable cause based on variables related to the underlying disease, acute respiratory failure characteristics, and radiographic findings. The cause of acute respiratory failure must then be confirmed using the most efficient, least invasive, and safest diagnostic tests. In patients with acute respiratory failure of undetermined cause, a standardised diagnostic investigation should be done immediately at admission before deciding whether to perform more invasive diagnostic procedures or to start empirical treatments. Collaborative and multidisciplinary clinical and research networks are crucial to improve our understanding of disease pathogenesis and causation and to develop less invasive diagnostic strategies and more targeted treatment options.

Efficacy and safety of trans-bronchial cryo in comparison with forceps biopsy in lung allograft recipients: Analysis of 402 procedures

BACKGROUND

Trans-bronchial forceps biopsy (TBFB) is the gold standard to establish the presence of allograft rejection or infection after lung transplantation. We aimed to analyze the diagnostic yield and safety of trans-bronchial cryobiopsy (TBCB) in lung allografts.

METHODS

Retrospective analysis of 402 TBB procedures in 362 lung recipients was performed between 2011 and 2016. Half of the cases (201) were performed by TBCB and the other half by TBFB. One hundred random slides of TBB specimens from lung allografts were reviewed for artifacts, bleeding, and histological evidence.

RESULTS

Both TBB groups were comparable in age, gender distribution, and time following transplantation. Acute rejection was diagnosed in 21.9% of the TBCB group vs 14.9% in the TBFB group (P = .09) and only 2 cases (1%) of nondiagnostic tissue in TBCB group and 4 cases (2%) in TBFB group (P = .685). Complications of pneumothorax and bleeding occurred in 9 (4.5%) vs 8 (4%) and 5 (2.5%) vs 4 (2%) in TBCB vs TBFB groups, respectively. The TBCB specimens were larger than TBFB (average 16.6 vs 6.6 mm² ; P < .001). Crush and bleeding artifacts were seen in 11 (22%) and 23 (46%) of TBFB, respectively, yet none in TBCB group (P < .001).

CONCLUSION

Trans-bronchial cryobiopsy is safe and effective for diagnosis of lung allograft rejection.

Transbronchial lung cryobiopsy: Associated complications

INTRODUCTION

Transbronchial lung cryobiopsy (TBC) has emerged as a diagnostic alternative to surgical lung biopsy in interstitial lung disease (ILD). Despite its less invasive nature, some associated complications have been described.

OBJECTIVE

To evaluate complications of TBC and associated factors.

METHODS

Prospective evaluation of all patients with ILD submitted to TBC in our centre. Clinicodemographic variables and factors associated to TBC complications were analyzed. The effect of the variables on the complication risk was evaluated by a logistic regression model.

RESULTS

Ninety patients were included (mean age 60±13 years; 58.9% male). Twenty-two patients presented pneumothorax, 18 (81.8%) of which were treated with chest tube drainage [median air leak time: 1 day (IQR=2)]. Grade 2 and 3 bleeding was observed in 13 (14.4%) cases. Presence of visceral pleura in the sample accounted for almost more than 10 times the odds of pneumothorax (OR=9.59, 95% CI 2.95-31.17, p<0.001). Increased body mass index (BMI) was associated with bleeding (16% additional odds for each BMI unit increase (OR=1.16, 95% CI 1.01-1.34, p=0.049).

CONCLUSION

The most frequent complication of TBC was pneumothorax, although rapidly reversible. There was a positive association between pneumothorax and the presence of pleura in the biopsy samples as well as between bleeding and increased BMI. More studies about TBC complications are needed to improve the selection of the candidates for this procedure.

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.

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

BACKGROUND

Diffuse parenchymal lung diseases (DPLDs) are common. An accurate diagnosis is essential due to differences in etiology, clinicopathologic features, therapeutic options, and prognosis. Transbronchial lung biopsies (TBLBs) are often limited by small specimen size, crush artifact, and other factors. Transbronchial lung cryobiopsies (TBLCs) are under investigation to overcome these limitations.

METHODS

We conducted a retrospective study of 56 patients in a single, tertiary-care academic center to compare the yield of both techniques when performed in the same patient. Patients underwent flexible bronchoscopy using moderate sedation with TBLB followed by TBLC in the most radiographically abnormal areas. Clinical data and postprocedural outcomes were reviewed, with a final diagnosis made utilizing a multidisciplinary approach.

RESULTS

The mean age of patients was 60 years and 54% were male. Comorbidities included COPD (14%) and prior malignancy (48%). The number of TBLB specimens ranged from 1 to 10 per patient (mean 4) and size varied from 0.1 to 0.8 cm. The number of TBLC specimens ranged from 1 to 4 per patient (mean 2) and size ranged from 0.4 to 2.6 cm. Both techniques provided the same diagnosis in 26 patients (46%). An additional 11 (20%) patients had a diagnosis established by adding TBLC to TBLB. Compared with TBLB, TBLC had a higher diagnostic yield in patients with hypersensitivity pneumonitis and interstitial lung disease. Only 2 patients required video-assisted thoracoscopic surgery to establish a diagnosis. Complications included pneumothorax (20%) and massive hemoptysis (2%).

CONCLUSION

TBLC used with TBLB can improve the diagnostic yield of flexible bronchoscopy in patients with DPLD.

Transbronchial cryobiopsy in diffuse parenchymal lung diseases

PURPOSE OF REVIEW

The diagnostic yield of conventional transbronchial lung biopsy varies among various parenchymal lung diseases: in pulmonary sarcoidosis and lymphangitis carcinomatosa, a diagnosis can be obtained in up to 80% of patients; this method is considered inadequate, however, in identifying more complex histological patterns such as usual interstitial pneumonitis or nonspecific interstitial pneumonitis, mainly because the specimens are tiny and the interpretation is confounded by crush artifacts. Recently, the use of cryoprobes has achieved a significant impact on this issue. This review is about this promising application of cryobiopsy in the diagnostic process of diffuse parenchymal lung diseases.

RECENT FINDINGS

Recent studies document that with transbronchial cryobiopsies, the diagnosis of usual interstitial pneumonitis can be made confidently by pathologists with a good interobserver agreement. Pneumothorax is the main complication (reported in up to one-quarter of cases in some series); bronchial bleeding is usually controlled using Fogarty balloon.

SUMMARY

Transbronchial cryobiopsy is a promising new technique that may become a valid alternative to surgical lung biopsy in the near feature.

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

Transbronchial lung cryobiopsy involves using a cryoprobe rather than forceps to obtain a bronchoscopic biopsy. Recent studies have shown that transbronchial cryobiopsy provides a larger specimen than conventional transbronchial forceps biopsy, and that the interobserver agreement in the interpretation of cryobiopsy specimens is comparable to that of a surgical lung biopsy. This is encouraging, and transbronchial lung cryobiopsy clearly has a role in the workup and diagnosis of interstitial lung diseases. However, very few patients who have been studied underwent both transbronchial lung cryobiopsy and surgical lung biopsy, and the available data suggest that the diagnostic accuracy of cryobiopsy may not be similar to that of surgical lung biopsy. Further study is needed before transbronchial lung biopsy can be recommended as a replacement for surgical lung biopsy.

Transbronchial lung biopsy with a flexible cryoprobe: First case report from India

Sarcoidosis and tuberculosis are granulomatous disorders that mimic each other both clinically and radiologically. Both can present with fever and pulmonary nodules and often require the performance of transbronchial lung biopsy (TBLB) for diagnosis. In recent studies, the flexible cryoprobe for carrying out TBLB has been found to be useful in the diagnosis of disorders diffusely involving the lung parenchyma. Here, we present the case of a 29-year-old man who presented with fever and cough and was found to have multiple small nodules in both lungs. TBLB with a flexible cryoprobe helped in differentiating between sarcoidosis and tuberculosis.

Safety and Diagnostic Yield of Transbronchial Lung Cryobiopsy in Diffuse Parenchymal Lung Diseases: A Comparative Study versus Video-Assisted Thoracoscopic Lung Biopsy and a Systematic Review of the Literature

BACKGROUND

A diagnosis of interstitial lung diseases (ILDs) may include surgical lung biopsy (SLB), which is associated with significant morbidity and mortality and also appreciable costs. Transbronchial lung cryobiopsy (TBLC) is adopting an important role.

OBJECTIVES

The aim of this study was to compare the diagnostic yield (DY) and safety of TBLC and SLB in a large cohort of patients and to perform a systematic review of the literature as well as a meta-analysis.

METHODS

We performed a retrospective analysis of 447 cases with ILD undergoing TBLC and/or SLB and a systematic review of the literature (MEDLINE and Embase for all original articles on the DY and safety of TBLC in ILDs up to July 2015).

RESULTS

A total of 150 patients underwent SLB and 297 underwent TBLC. The median time of hospitalization was 6.1 days (SLB) and 2.6 days (TBLC; p < 0.0001). Mortality due to adverse events was observed for 2.7% (SLB) and 0.3% (TBLC) of the patients. Pneumothorax was the most common complication after TBLC (20.2%). No severe bleeding was observed. TBLC was diagnostic for 246 patients (82.8%), SLB for 148 patients (98.7%, p = 0.013). A meta-analysis of 15 investigations including 781 patients revealed an overall DY of 0.81 (0.75-0.87); the overall pooled probability of developing a pneumothorax, as retrieved from 15 studies including 994 patients, was 0.06 (95% CI 0.02-0.11).

CONCLUSION

Cryobiopsy is safe and has lower complication and mortality rates compared to SLB. TBLC might, therefore, be considered the first diagnostic approach for obtaining tissue in ILDs, reserving the surgical approach for cases in which TBLC is not diagnostic.

A New Tool for Transbronchial Cryobiopsies in the Lung: An Experimental Feasibility ex vivo Study

BACKGROUND

Transbronchial cryobiopsy (TBCB) is a minimally invasive procedure to establish a diagnosis of interstitial lung disease though with the disadvantage that samples have to be extracted together with the bronchoscope.

OBJECTIVES

The aim of the present study was to evaluate the feasibility of a new cryoprobe with which biopsy samples can be obtained through the working channel of the flexible bronchoscope.

METHODS

The feasibility of obtaining transbronchial specimens with TBCB was tested and the technique was compared to transbronchial forceps biopsy (TBFB) in a prospectively randomized ex vivo animal study using a standard flexible bronchoscopy technique. The rate of successful biopsies and the duration of the sampling procedure were recorded for both methods. Size and quality of the biopsies were histologically evaluated and measured.

RESULTS

Biopsy samples could be obtained in 93.3% of TBCB and in 79.0% of TBFB procedures (p = 0.182). Sampling procedure time did not differ in any clinically relevant manner between the two methods. The mean specimen area of TBCB samples was significantly higher compared to that of TBFB samples (8.08 ± 5.80 vs. 2.61 ± 2.14 mm2; p < 0.0001). TBCB specimens showed less artifacts and a significantly higher percentage of alveolar tissue (53.57 vs. 25.42%; p = 0.0285) than TBFB specimens.

CONCLUSIONS

It is feasible to retrieve TBCB samples of good quality and size with the new mini cryoprobe through the working channel of the bronchoscope, while the bronchoscope remains within the central airways throughout the whole procedure. Further studies are necessary to evaluate the safety and efficacy in an in vivo setting.

From electrocautery, balloon dilatation, neodymium-doped:yttrium-aluminum-garnet (Nd:YAG) laser to argon plasma coagulation and cryotherapy

Over the past decade, there has been significant advancement in the development/application of therapeutics in thoracic diseases. Ablation methods using heat or cold energy in the airway is safe and effective for treating complex airway disorders including malignant and non-malignant central airway obstruction (CAO) without limiting the impact of future definitive therapy. Timely and efficient use of endobronchial ablative therapies combined with mechanical debridement or stent placement results in immediate relief of dyspnea for CAO. Therapeutic modalities reviewed in this article including electrocautery, balloon dilation (BD), neodymium-doped:yttrium-aluminum-garnet (Nd:YAG) laser, argon plasma coagulation (APC), and cryotherapy are often combined to achieve the desired results. This review aims to provide a clinically oriented review of these technologies in the modern era of interventional pulmonology (IP).

Lung Transplantation

The therapeutic options for patients with advanced pulmonary parenchymal or vascular disorders are currently limited. Lung transplantation remains one of the few viable interventions, but on account of the insufficient donor pool only a minority of these patients actually undergo the procedure each year. Following transplantation there are a number of early and late allograft complications such as primary graft dysfunction, allograft rejection, infection, post-transplant lymphoproliferative disorder and late injury that is now classified as chronic lung allograft dysfunction. The pathologist plays an essential role in the diagnosis and classification of these myriad complications. Although the transplant procedures are performed in selected centers patients typically return to their local centers. When complications arise it is often the responsibility of the local pathologist to evaluate specimens. Therefore familiarity with the pathology of lung transplantation is important.

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.