Cryobiopsy in the diagnosis of diffuse interstitial lung disease: yield and cost-effectiveness analysis

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.

[Influence of Clinical Practice Guidelines on the Diagnosis and Treatment of Idiopathic Pulmonary Fibrosis. Data from the Registry of the Spanish Society of Pulmonology and Thoracic Surgery]

Objective

The objective of the study was to analyze the diagnostic process and the time until the start of treatment of patients with idiopathic pulmonary fibrosis in relation to the publication of successive clinical practice guide.

Material and methods

Multicenter, observational, ambispective study, in which patients includes in the idiopathic pulmonary fibrosis registry of the Spanish Society of Pulmonologist and Thoracic Surgery were analyzed. An electronic data collection notebook was enabled on the society's website. Sociodemographic and clinical variables were collected at diagnosis and follow-up of the patients.

Results

From January 2012 to december 2019, 1064 patients were included in the registry, with 929 finally analyzed. The diagnosis process varied depending on the year in which it was performed, and the radiological pattern observed in the high-resolution computed tomography. Up to 26.3% of the cases (244) were diagnosed with chest high-resolution computed tomography and clinical evaluation. Surgical biopsy was used up to 50.2% of cases diagnosed before 2011, while it has been used in 14.2% since 2018. The median time from the onset of symptoms to diagnosis was 360 days (IQR 120-720), taking more than 2 years in the 21.0% of patients. A percentage of 79.4 of patients received antifibrotic treatment. The average time from diagnosis to the antifibrotic treatment has been 309 ± 596.5 days, with a median of 49 (IQR 0-307).

Conclusions

The diagnostic process, including the time until diagnosis and the type of test used, has changed from 2011 to 2019, probably due to advances in clinical research and the publication of diagnostic-therapeutic consensus guidelines.

Transbronchial Lung Cryobiopsy Performed with Cone Beam Computed Tomography Guidance Versus Fluoroscopy: A Retrospective Cohort Review

PURPOSE

Determining the cause of interstitial lung disease (ILD) remains challenging. While surgical lung biopsy remains the gold standard approach, risks associated with it may be prohibitive. Transbronchial lung cryobiopsy (TBLC) is a minimally invasive alternative with an improved safety profile and acceptable diagnostic accuracy. We retrospectively assessed whether the use of Cone Beam computed tomography guidance for TBLC (TBLC-CBCT) improves safety and diagnostic yield compared to performing TBLC with fluoroscopic guidance (TBLC-F).

METHODS

A retrospective cohort review of 120 patients presenting for evaluation of newly diagnosed ILD was performed. Demographic data, pulmonary function test values, chest imaging pattern, procedural information, and final multidisciplinary discussion (MDD) diagnosis were recorded.

RESULTS

62 patients underwent TBLC-F and 58 underwent TBLC-CBCT. Patients undergoing TBLC-CBCT were older (67.86 ± 10.97 vs 61.45 ± 12.77 years, p = 0.004) and had a higher forced vital capacity percent predicted (73.80 ± 17.32% vs 66.00 ± 17.45%, p = 0.03) compared to the TBLC-F group. The average probe-to-pleura distance was 5.1 ± 2.3 mm in the TBLC-CBCT group with 4.0 ± 0.3 CBCT spins performed. Pneumothorax occurred more often in the TBLC-F group (n = 6, 9.7%) compared to the TBLC-CBCT group (n = 1, 1.7%, p = 0.06). Grade 2 bleeding only occurred in the TBLC-F group (n = 4, 6.5%). A final MDD diagnosis was obtained in 89% (n = 57) of TBLC-F patients and 95% (n = 57) of TBLC-CBCT patients.

CONCLUSIONS

TBLC-CBCT appears to be safer compared to TBLC-F with both approaches facilitating an MDD diagnosis. Further studies from multiple institutions randomizing patients to each modality are needed to confirm these findings.

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.

Real-world utility of a genomic classifier in establishing a diagnosis of newly identified interstitial lung disease

BACKGROUND

Diagnosing interstitial lung disease (ILD) remains challenging. Guidelines recommend utilizing a multidisciplinary discussion (MDD) to review clinical and radiographic data and if diagnostic uncertainty persists, then to obtain histopathology. Surgical lung biopsy and transbronchial lung cryobiopsy (TBLC) are acceptable methods, but risks of complications may be prohibitive. The Envisia genomic classifier (EGC) represents another option to determine a molecular usual interstitial pneumonia (UIP) signature to facilitate an ILD diagnosis at MDD with high sensitivity and specificity. We evaluated the concordance between TBLC and EGC at MDD and the safety of this procedure.

METHODS

Demographic data, pulmonary function values, chest imaging pattern, procedural information, and MDD diagnosis were recorded. Concordance was defined as agreement between the molecular EGC results and histopathology from TBLC in the context of the patient's High Resolution CT pattern.

RESULTS

49 patients were enrolled. Imaging demonstrated a probable (n = 14) or indeterminate (n = 7) UIP pattern in 43% and an alternative pattern in 57% (n = 28). EGC results were positive for UIP in 37% (n = 18) and negative in 63% (n = 31). MDD diagnosis was obtained in 94% (n = 46) with fibrotic hypersensitivity pneumonitis (n = 17, 35%) and IPF (n = 13, 27%) most common. The concordance between EGC and TBLC at MDD was 76% (37/49) with discordant results seen in 24% (12/49) of patients.

CONCLUSIONS

There appears to be reasonable concordance between EGC and TBLC results at MDD. Efforts clarifying the contributions of these tools to an ILD diagnosis may help identify specific patient populations that may benefit from a tailored diagnostic approach.

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

Risk factors of clinically significant complications in transbronchial lung cryobiopsy: A prospective multi-center study

BACKGROUND

The use of a transbronchial lung cryobiopsy (TBLC) is increasing as a diagnostic method of interstitial lung diseases (ILD). This study aimed to evaluate risk factors associated with clinically significant complications of TBLC in ILD patients.

METHODS

Patients referred to Kuopio or Tampere university hospitals, in Finland, for a suspected ILD were included. The TBLC was performed in an outpatient setting for 100 patients. Patients were mechanically ventilated in general anesthesia. Fluoroscopy guidance and prophylactic bronchial balloon were used. Complications, such as bleeding, pneumothorax, infections, and mortality were recorded. Moderate or serious bleeding, pneumothorax, or death ≤90 days were defined as clinically significant complications. A multivariable model was created to assess clinically significant complications.

RESULTS

The extent of traction bronchiectasis (Odds ratio [OR] 1.30, Confidence interval [CI] 1.03-1.65, p = 0.027) and young age (OR 7.96, CI 2.32-27.3, p = 0.001) were associated with the risk of clinically significant complications whereas the use of oral corticosteroids ≤30 days before the TBLC (OR 3.65, CI 0.911-14.6, p = 0.068) did not quite reach statistical significance. A history of serious cough was associated with the risk of pneumothorax (OR 4.18, CI 1.10-16.0, p = 0.036). Procedure associated mortality ≤90 days was 1%.

CONCLUSION

The extent of traction bronchiectasis on HRCT and young age were associated with the risk of clinically significant complications whereas oral corticosteroid use did not quite reach statistical significance. A history of serious cough was associated with the risk of clinically significant pneumothorax.

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.

A systematic review on the economic burden of interstitial lung disease and the cost-effectiveness of current therapies

Background

The economic burden of interstitial lung disease (ILD) is unknown, limiting informed resource allocation and planning. We sought to conduct the first systematic review on the direct, indirect, and overall costs associated with ILD and to evaluate the cost-effectiveness of current therapies globally.

Methods

We conducted systematic reviews of ILD disease cost studies and cost-effectiveness analyses (CEAs) using MEDLINE, Embase, and Web of Science databases between 2000 and 2020. We compared ILD costs between countries according to the share of costs towards each country’s respective gross domestic product (GDP) per capita. Costs are reported in 2020 USD.

Results

We identified 25 disease cost studies and 7 CEAs. The direct medical costs ranged between $1824 and $116,927 annually per patient (median $32,834; 14–180% of GDP per capita in Western countries). The leading drivers of direct costs were inpatient (55%), outpatient (22%), and medication costs (18%), based on pooled estimates. Annual indirect costs ranged from $7149 to $10,902 per employed patient (median $9607; 12–23% of GDP per capita). Among the 7 CEAs, only 1 study (14%) showed an ILD therapy (ambulatory oxygen) was cost-effective compared to best supportive care.

Conclusion

The direct and indirect costs associated with ILD are consistently high in all countries with available data, with cost-effectiveness profiles of new therapies generally undesirable. Globally, the median total direct cost for ILD equates to 51% of a country’s GDP per capita and has been increasing over time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01922-2.

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.

Optimize Initial Freezing Time of Transbronchial Cryobiopsy for the Diagnosis of Interstitial Lung Disease: A Prospective Randomized Parallel Group Study

BACKGROUND

Transbronchial cryobiopsy (TBCB) is increasingly being identified as a potential alternative for the diagnosis of interstitial lung disease (ILD). The specimen size of TBCB is positively related to the freezing time. However, the proper initial freezing time for the clinical application of TBCB in ILD remains unknown.

METHODS

A prospective randomized parallel group study was employed to investigate ILD patients with unclear diagnosis, who were admitted to the First Affiliated Hospital of Guangzhou Medical University from May 2019 to October 2020 and required TBCB. All patients were randomly divided into 4 groups according to the different freezing times of TBCB: 3 s, 4 s, 5 s, and 6 s groups. All operations were performed under intravenous anesthesia with endotracheal intubation, 60-65 bar pressure of freezing gas source, and 1.9-mm cryoprobe. Compare differences among groups in specimen size, complications, pathological diagnosis efficiency, and multidisciplinary discussion (MDD) diagnostic efficiency.

RESULTS

A total of 100 patients were recruited and randomly assigned into 4 groups (n = 25 each group). The specimen sizes of TBCB in ILD were positively correlated with the freezing time (r = 0.639, p < 0.05). None of the patients experienced Grade 3 severe bleeding. Pneumothorax occurred in 1 patient in the 4 s, 5 s, and 6 s groups, respectively. The diagnostic yield of MDD in the 3 s, 4 s, 5 s, and 6 s groups were 64%, 88%, 88%, and 96%, respectively (p < 0.05), but showing no significant differences among 4 s, 5 s, and 6 s groups.

CONCLUSIONS

The specimen size and diagnostic efficiency of TBCB in ILD increased with a longer freezing time. When the freezing gas pressure is 60-65 bar, we recommended 4 s as the initial freezing time of TBCB, and this time is associated with high diagnostic efficiency and low incidence of complications.

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.

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.

Interventional pulmonology during COVID-19 pandemic: current evidence and future perspectives

COVID-19, caused by SARS-CoV-2 infection, has become increasingly prevalent worldwide, reaching a pandemic stage in March 2020. The organization of health care services had to change because of this new disease, with the need to reallocate staff and materials, besides changing management protocols. A very important challenge is not to expose patients and health care workers to the risk of infection and not to waste personal protective equipment (PPE). In the field of interventional pulmonology, various aspects related to COVID-19 must be taken into great consideration. Although bronchoscopy is not a first-line test for patients with suspected SARS-CoV-2 infection, it has a role in selected cases and it can be useful for differential diagnosis. However, bronchoscopy is an aerosol-generating procedure, that’s why its unjustified use could contribute to propagate the virus. For this reason, the utility of each procedure must be carefully evaluated, the patient has to be properly investigated before the procedure, which has to be performed with specific precautions, including adequate PPE. In this review, we summarize the knowledge and the principal statements about endoscopic activity in COVID-19 period, in both diagnosis of COVID-19 and management of patients. How to safely perform both bronchoscopic and pleural-related procedures (thoracoscopy, pleural biopsy and drainage of pleural effusions) is described with the aim to help the staff to decide when and how performing a procedure. We also highlight how interventional pulmonology could help in matter of complications related to COVID-19.

Integration of cryobiopsies for interstitial lung disease diagnosis is a valid and safe diagnostic strategy-experiences based on 250 biopsy procedures

Background

Transbronchial cryobiopsies has become increasingly used in the diagnostic workup in patients suspected of having interstitial lung disease. The procedure is associated with less complications, morbidity and mortality compared to surgical lung biopsies although with a diagnostic yield that is not as high, but close to that of surgical lung biopsies. The aim of the present study was to describe the complications and diagnostic yield and their prognostic factors.

Methods

All patients undergoing transbronchial cryobiopsies at the Department of Respiratory Diseases and Allergy, Aarhus University Hospital, were included in this prospective observational cohort study.

Results

A total of 250 patients were included [61% male, mean age 66 years (range, 22–81 years)]. Pneumothorax was detected in 70 (28%) of the patients, moderate hemorrhage in 53 (21%) and severe hemorrhage in 2 (1%) of the patients. Hemorrhage was associated with central biopsies, but not with anticoagulant therapy. None of the complications were related to lung function, exercise capacity, biopsy or probe size. Only one patient experienced an acute exacerbation. Three-month mortality was 0.4% (1 patient), caused by cancer and unrelated to the procedure. Cryobiopsies contributed to the final diagnosis in 72% of the patients and after multidisciplinary team discussion, a consensus diagnosis was obtained in 82% of the patients. The gender, the total sum of biopsy sizes, number of biopsies and presence of more than 50% alveolar tissue in biopsies increased the diagnostic yield.

Conclusions

Our study confirms that using cryobiopsies in the diagnostic setup for interstitial lung diseases is safe with a limited risk of acute exacerbations and mortality. Cryobiopsies contribute to the diagnosis in the majority of patients.

Implementation of transbronchial lung cryobiopsy in a tertiary referral center for interstitial lung diseases: a cohort study on diagnostic yield, complications, and learning curves

Background

Transbronchial lung cryobiopsy (TBLC) has been introduced as an alternative to surgical lung biopsy (SLB) in the diagnostics of interstitial lung diseases (ILD). Despite controversy on safety, TBLC is increasingly implemented in ILD centers with an apparent diagnostic yield comparable to SLB. The aim of this study was to assess TBLC implementation experiences from a tertiary Danish ILD center regarding diagnosis, complications, and learning curves for TBLC performance.

Methods

TBLC was prospectively performed in a cohort of patients with unclassifiable ILD based on a preceding multidisciplinary clinical and radiological revision. TBLC was performed as an outpatient procedure with the patients in general anesthesia using a flexible bronchoscope with 1.9 or 2.4 mm cryoprobes. Learning curves for TBLC performance were calculated using cumulated sum (CUSUM) scores for diagnostic yield, pneumothorax, and bleeding.

Results

From February 2017 to March 2020 141 patients (86 (61%) men, median age 69 years [IQR, 60–74 years]) had TBLC performed. A histological and confirmative diagnosis was made in 101 patients (75.2%) and 124 patients (87.9%, i.e. clinical diagnostic yield), respectively, in whom idiopathic interstitial pneumonias constituted the majority (67.3%) of the clinical diagnoses. We observed 2 deaths (1.4%) within 30 days of TBLC, but no procedure-related mortality or severe bleeding. Moderate bleeding occurred in 23 patients (16.3%), pneumothorax in 21 patients (14.9%) with only 14 patients (9.9%) requiring a pleural drain. Based on the CUSUM score analysis, the diagnostic yield obtained was satisfactory throughout the period.

Conclusion

This study reports experiences of outpatient TBLC implementation in a tertiary referral ILD center from the largest investigated TBLC cohort in Scandinavia The diagnostic yield and prevalence of complications obtained by TBLC from this single center study on unclassifiable ILD support outpatient TBLC as a valuable and safe alternative to SLB to diagnose ILD in well-selected patients. The learning curves for TBLC were acceptable in the hands of experienced bronchoscopists.

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.

Safety and diagnostic yield of transbronchial lung cryobiopsy by flexible bronchoscopy using laryngeal mask airway in diffuse and localized peripheral lung diseases: A single-center retrospective analysis of 326 cases

Background

Intubation with either an endotracheal tube or a rigid bronchoscope is generally preferred to provide airway protection as well as to manage unpredictable complications during transbronchial lung cryobiopsy (TBLC). The laryngeal mask airway has been described as a safe and convenient tool for airway control during bronchoscopy.

Aims and Objectives

In this study, we evaluated the safety and outcome of using a laryngeal mask airway (LMA) as a conduit for performing TBLC by flexible video bronchoscopy (FB).

Methods

We retrospectively analyzed the database of the patients who underwent TBLC between November 2015 and September 2019. The procedure was performed using FB through LMA under general anesthesia. Prophylactic occlusion balloon was routinely used starting January 2017 onwards. Radial endobronchial ultrasound (R-EBUS) guidance was used for TBLC in the localized lung lesions when deemed necessary. Multidisciplinary consensus diagnostic yield was determined and periprocedural complications were recorded.

Results

A total of 326 patients were analysed. The overall diagnostic yield was 81.60% (266/326) which included a positive yield of 82.98% (161/194) in patients with diffuse lung disease and 79.54% (105/132) in patients with localized disease. Serious bleeding complication occurred in 3 (0.92%) cases. Pneumothorax was encountered in 8 (2.45%) cases. A total of 9 (2.76%) cases had at least 1 major complication.

Conclusion

This study demonstrates that the use of LMA during TBLC by flexible bronchoscopy allows for a convenient port of entry, adequate airway support and effective endoscopic management of intrabronchial haemorrhage especially with the use of occlusion balloon.

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.

Assessment and Management of Occupational Hypersensitivity Pneumonitis

The diagnosis and treatment of occupational hypersensitivity pneumonitis (OHP) remain complex and challenging in the absence of diagnostic gold standards or clinical guidelines. This review provides an update of the recent literature regarding the different presentations of OHP and the diagnostic yield and value of the diagnostic tests currently available, which include occupational and medical history, laboratory tests (serum-specific immunoglobulins, environmental sampling), imaging, bronchoalveolar lavage, transbronchial biopsy, transbronchial cryobiopsy, surgical lung biopsy, and specific inhalation challenges. These tools provide a precise differential diagnosis within the framework of interstitial lung diseases. However, among the chronic fibrotic forms, distinguishing OHP from sarcoidosis, nonspecific interstitial pneumonia and idiopathic pulmonary fibrosis remains a diagnostic challenge. Avoidance of exposure is pivotal for OHP management, whereas corticosteroids are fundamental in the pharmacological approach to this disease. In addition, studies describing the long-term benefits of immunosuppressive and antifibrotic agents have increased the use of these treatments in OHP.

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. 

Granulomatous and lymphocytic interstitial lung disease diagnosed by transbronchial lung cryobiopsy

Granulomatous and lymphocytic interstitial lung disease is a pulmonary complication of common variable immune deficiency with significant morbidity and increased mortality. Diagnosis has historically been obtained by surgical lung biopsy as transbronchial biopsy typically yields insufficient tissue for definitive diagnosis from a disease process with a patchy distribution. However, the potential for significant morbidity and mortality with surgical lung biopsy exists, necessitating the development of alternative diagnostic approaches. We present a case of granulomatous and lymphocytic interstitial lung disease confirmed through minimally invasive transbronchial lung cryobiopsy and discuss the role of this modality in diagnosing interstitial lung disease.

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.

Feasibility and utility of transbronchial cryobiopsy in precision medicine for lung cancer: Prospective single-arm study

Cryoprobe is a novel transbronchial biopsy (TBB) tool that yields larger tissue samples than forceps. Pathological diagnosis and biomarker analysis, such as genetic alterations and programmed death‐ligand 1 (PD‐L1) expression, are paramount for precision medicine against lung cancer. We evaluated the safety and usefulness of cryoprobe TBB for lung cancer diagnosis and biomarker analysis. In this single‐center, prospective single‐arm study, patients suspected of having or diagnosed with primary lung cancer underwent cryoprobe TBB using flexible bronchoscopy after conventional forceps TBB from the same lesion. Cryoprobe TBB was performed in 121 patients. The incidence rate of severe bleeding and serious adverse events (4% [90% confidence interval: 2%‐9%]) was significantly lower than the expected rate (20% with 30% threshold, P < 0.01). Combining both central and peripheral lesions, the diagnostic yield rate of cryoprobe samples was 76% and that of forceps samples was 84%. Compared with forceps TBB samples, cryoprobe TBB samples were larger (cryoprobe 15 mm² vs forceps 2 mm²) and resulted in a larger proportion of definite histomorphological diagnosis (cryoprobe 86% vs forceps 74%, P < 0.01), larger amounts of DNA extracted from samples (median: cryoprobe, 1.60 µg vs forceps, 0.58 µg, P = 0.02) and RNA (median: cryoprobe, 0.62 µg vs forceps, 0.17 µg, P < 0.01) extracted from samples, and tended to yield greater rates of PD‐L1 expression >1% (51% vs 42%). In conclusion, cryoprobe is a safe and useful tool for obtaining lung cancer tissue samples of adequate size and quality, which allow morphological diagnosis and biomarker analysis for precision medicine against lung cancer.

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.

Transbronchial lung cryobiopsy may be of value for nonresolving acute respiratory distress syndrome: case series and systematic literature review

BACKGROUND

Identification of pathologic features is helpful for the management of nonresolving acute respiratory distress syndrome (ARDS). Transbronchial lung cryobiopsy (TBLC) is a novel biopsy technique that may have comparable utility to surgical biopsy. The aim of this study was to assess the value of TBLC in patients with nonresolving ARDS.

METHODS

All patients with nonresolving ARDS who underwent TBLC from January 2019 to August 2019 in a tertiary medical ICU were included. In addition, a literature search of TBLC for ARDS was performed by searching PubMed, EMBASE, ATS/ERS/APSR meeting abstracts, ClinicalTrials.gov , and Google Scholar. Data on complications, histologic diagnosis, management changes, and outcomes were analysed.

RESULTS

Five patients (three women and two men) underwent TBLC. None of the patients developed pneumothorax, although two patients developed massive bleeding, which was controlled by continuous occlusion using bronchial blockers. There were no procedure-related deaths. Diffuse alveolar damage (DAD) and alternative histologic patterns were found in two and three patients, respectively, resulting in management changes in all cases. The literature search yielded four studies, which together with the present study comprised data from 25 cases in which TBLC was used in nonresolving ARDS. The summary diagnostic yield was 92% (23/25). Only 44% (11/25) of cases were proven to be DAD. TBLC contributed to management changes in 80% of patients (20/25). Procedure-related complications consisted of pneumothorax (16%, 4/25), significant bleeding (12%, 3/25), and persistent air leaks (8%, 2/25). There were no procedure-related deaths. The follow-up survival rate was 61.9% (13/21).

CONCLUSIONS

The complications of TBLC in selected patients with nonresolving ARDS may be acceptable. The procedure may have a high diagnostic yield and can lead to a re-evaluation of the diagnosis as well as changes in patient management. Further investigations with larger sample sizes are required.

Complications and hospital admission in the following 90 days after lung cryobiopsy performed in interstitial lung disease

Transbronchial lung cryobiopsy (TBLC) is an emerging technique for the diagnosis of interstitial lung disease (ILD), but its risk benefit ratio has been questioned. The objectives of this research were to describe any adverse events that occur within 90 days following TBLC and to identify clinical predictors that could help to detect the population at risk.

METHODS

We conducted an ambispective study including all patients with suspected ILD who underwent TBLC. Data were collected concerning the safety profile of this procedure and compared to various clinical variables.

RESULTS

Overall, 257 TBLCs were analysed. Complications were observed in 15.2% of patients; nonetheless, only 5.4% of all patients required hospital admission on the day of the procedure. In the 30 and 90 days following the TBLC, rates of readmission were 1.3% and 3.5% and of mortality were 0.38%, and 0.78% respectively. Two models were built to predict early admission (AUC 0.72; 95% CI 0.59-0.84) and overall admission (AUC 0.76; 95% CI 0.67-0.85).

CONCLUSIONS

Within 90 days after TBLC, 8.9% of patients suffered a complication serious enough to warrant hospital admission. Modified MRC dyspnoea score ≥2, FVC<50%, and a Charlson Comorbidity Index score ≥2 were factors that predicted early and overall admission.

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.

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.

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.

Transbronchial Lung Cryobiopsy in Interstitial Lung Diseases: Best Practice

The lung biopsy in interstitial lung disease (ILD) represents an important diagnostic step when the clinical and radiological data are insufficient for a firm diagnosis. A growing body of evidence suggests the utility of transbronchial lung cryobiopsy (TBLC) in the diagnostic algorithm of ILD as it allows, compared to transbronchial lung biopsy with conventional forceps, a better identification of complex histological patterns - such as usual interstitial pneumonia - and can provide information which has a clinical impact on the multidisciplinary discussion similar to that provided by surgical lung biopsy. Performed correctly, it appears to have a better safety profile than surgery. The decision to perform a lung biopsy should be a multidisciplinary decision process where it is felt that there is sufficient diagnostic doubt after a careful clinical evaluation including review of the computed tomograms of the thorax. The presence of severe pulmonary hypertension (> 50 mm Hg), poor lung function (FVC < 50%), or dismissed gas transfer (DLCO of < 35%) are considered relative contraindications for TBLC. Anticoagulants and antiplatelet drugs should be discontinued for the minimum period required for the specific drugs. The greatest consideration should be given to ensure the biopsy is performed safely and we recommend the use of either an endotracheal tube or rigid bronchoscopy. Deep sedation or general anesthesia allow better control of the procedure and a better patient experience. Prophylactic balloon blockers should be used to tamponade any bleeding and also to prevent overspill of blood from the segment that is being sampled. The procedure should be performed under fluoroscopy to ensure that samples are ideally obtained about 10 mm from the pleural edge. The cryoprobe is activated for about 5 s for the first biopsy and then adjusted according to the sample size obtained. With a careful standardized approach it is possible to obtain good-quality lung specimens for diagnosis in a safe manner.

Tyrosine Kinase Inhibitor-Induced Interstitial Lung Disease: Clinical Features, Diagnostic Challenges, and Therapeutic Dilemmas

Since the approval of the first molecularly targeted tyrosine kinase inhibitor (TKI), imatinib, in 2001, TKIs have heralded a new era in the treatment of many cancers. Among their innumerable adverse effects, interstitial lung disease (ILD) is one of the most serious, presenting most frequently with dyspnea, cough, fever, and hypoxemia, and often treated with steroids. Of the 28 currently approved TKIs, 16 (57 %) are reported to induce ILD with varying frequency and/or severity. The interval from drug administration to onset of ILD varies between patients and between TKIs, with no predictable time course. Its incidence is variously reported to be approximately 1.6-4.3 % in Japanese populations and 0.3-1.0 % in non-Japanese populations. The mortality rate is in the range of 20-50 %. Available evidence (primarily following the use of erlotinib and gefitinib in Japan because of the unique susceptibility of that population) has identified a number of susceptibility and prognostic risk factors (male sex, a history of smoking, and pre-existing pulmonary fibrosis being the main ones). Although the precise mechanism is not understood, collective evidence suggests that immune factors may be involved. If TKI-induced ILD is confirmed by thorough evaluation of the patient and exclusion of other causes, management is supportive, and includes discontinuation of the culprit TKI and administration of steroids. Discontinuing the culprit TKI presents a clinical dilemma because the diagnosis of TKI-induced ILD in a patient with pre-existing pulmonary fibrosis can be challenging, the patient may have TKI-responsive cancer with no suitable alternative, and switching to an alternative agent, even if available, carries the risk of the patient experiencing other toxic effects. Preliminary evidence suggests that therapy with the culprit TKI may be continued under steroid cover and/or at a reduced dose. However, this approach requires careful individualized risk-benefit analysis and further clinical experience.

Feasibility of Radial Endobronchial Ultrasound-Guided Bronchoscopic Cryobiopsy without Fluoroscopy for Lung Parenchymal Lesions

Background

Cryobiopsy is used to biopsy peripheral lung lesions through flexible bronchoscopy with fluoroscopic guidance. However, fluoroscopy is not available at some institutions. This study evaluated the feasibility of radial endobronchial ultrasound-guided bronchoscopic cryobiopsy without fluoroscopy.

Methods

This retrospective study was conducted at Chang Gung Memorial Hospital, Linkou branch, in Taiwan. This study enrolled patients who received bronchoscopy examinations with cryotechnology between July 2014 and June 2016. The data were collected through medical chart review.

Results

During the study period, 101 patients underwent bronchoscopy examinations with cryotechnology. Ninety patients with endobronchial tumors were excluded from this study. Eleven patients who underwent radial endobronchial ultrasound-guided bronchoscopic cryobiopsy for lung parenchymal lesions were enrolled into this study. The mean age was 61.1 ± 13.8 years. Five patients were men, and the other six were women. The number of cryobiopsies ranged from 1 to 3. In the histological biopsies, the mean specimen diameter was 0.53 ± 0.23 cm, and the mean biopsy area was 0.20 ± 0.19 cm². Nine of 11 patients had pathological diagnoses. No complications, including pneumothorax, respiratory failure, or major bleeding, were recorded after the procedure.

Conclusions

Endobronchial ultrasound is used to ensure biopsy location, and endobronchial ultrasound-guided cryobiopsy is a feasible technique to biopsy peripheral lung lesions in selected cases at institutions without fluoroscopy equipment. This study provided some rationale for further studies examining the impact of fluoroscopy.

Management of oral antiplatelet agents and anticoagulation therapy before bronchoscopy

Although, bronchoscopy is a relatively safe procedure, small amount of bleeding in the airway can have serious consequences. Careful consideration of the risks of diagnostic and therapeutic bronchoscopic intervention can help minimize potential complications. With increasing number of patients using antiplatelet and anticoagulation therapies, strategies for minimizing thromboembolic and operative bleeding events need to be included in the risk and benefit analyses. Growing evidence suggests that aspirin is safe and does not increase bleeding during bronchoscopy. In addition, despite small studies reporting that it may be safe to perform bronchoscopic procedures that have low risk for bleeding such as endobronchial ultrasound with transbronchial needle aspiration on clopidogrel, it is still recommended to hold it for 7 days prior to performing elective bronchoscopy. It is recommended to hold vitamin K antagonist, as well as new oral anticoagulation agents prior to bronchoscopy. The timing for pre-procedural discontinuation of anticoagulation therapy and the decision to bridge depend on the agent used, the renal function and the thromboembolic risk. In this review article, we will discuss available data regarding management of anticoagulation and antiplatelet therapy as it applies to bronchoscopic procedures.

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.

Transbronchial cryobiopsy in interstitial lung disease: experience in 106 cases - how to do it

Transbronchial biopsy using forceps (TBB) is the first diagnostic technique performed on patients with interstitial lung disease (ILD). However, the small size of the samples and the presence of artefacts in the tissue obtained make the yield variable. Our objectives were 1) to attempt to reproduce transbronchial cryobiopsy under the same conditions with which we performed conventional TBB, that is, in the bronchoscopy unit without intubating the patient and without fluoroscopy or general anaesthesia; 2) to describe the method used for its execution; and 3) to analyse the diagnostic yield and its complications. We carried out a prospective study that included 106 patients with clinical and radiological features suggestive of ILD who underwent cryo-transbronchial lung biopsy (cryo-TBB) under moderate sedation without endotracheal intubation, general anaesthesia or use of fluoroscopy. We performed the procedure using two flexible bronchoscopes connected to two video processors, which we alternated until obtaining the number of desired samples. A definitive diagnosis was obtained in 91 patients (86%). As for complications, there were five pneumothoraces (4.7%) and in no case was there severe haemorrhage or exacerbation of the underlying interstitial disease. Cryo-TBB following our method is a minimally invasive, rapid, safe and economic technique that can be performed in a bronchoscopy suite under moderate sedation without the need for intubating the patient or using fluoroscopy and without requiring general anaesthesia.

Idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis is a fibrosing interstitial pneumonia associated with the radiological and/or histological pattern of usual interstitial pneumonia. Its aetiology is unknown, but probably comprises the action of endogenous and exogenous micro-environmental factors in subjects with genetic predisposition. Its diagnosis is based on the presence of characteristic findings of high-resolution computed tomography scans and pulmonary biopsies in absence of interstitial lung diseases of other aetiologies. Its clinical evolution is variable, although the mean survival rate is 2-5 years as of its clinical presentation. Patients with idiopathic pulmonary fibrosis may present complications and comorbidities which modify the disease's clinical course and prognosis. In the mild-moderate disease, the treatment consists of the administration of anti-fibrotic drugs. In severe disease, the best therapeutic option is pulmonary transplantation. In this paper we review the diagnostic and therapeutic aspects of the disease.