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

The application of bronchoscopy in the assessment of immune checkpoint inhibitor-related pneumonitis severity and recurrence

To explore the role of bronchoscopy for the assessment of checkpoint inhibitor pneumonitis (CIP), a retrospective single-center study was conducted to assess patients diagnosed with CIP at grade 2 or above and also underwent bronchoscopy between January 2020 and December 2022. Clinical data and bronchoscopic findings were recorded. The treatment data and prognosis information were collected. Twenty-one patients who underwent bronchoscopy and were diagnosed with CIP were enrolled in this study. All patients underwent bronchoalveolar lavage fluid (BALF) analysis. Of them, T lymphocyte subsets of BALF were tested in 15 cases. Transbronchial cryobiopsy (TBCB) was performed in 8 patients, and transbronchial lung biopsy was performed in 5 patients. 3 patients developed pneumothorax after TBCB and all recovered without serious compilations.14 patients experienced grade 2 CIP, while 7 patients ≥ grade 3 CIP. Symptoms were improved in 19 (90.5%) patients after standard treatment adhering to CIP guidelines. However, 5 patients relapsed during steroid tapering. Factors related to the severity and recurrence of CIP were analyzed. Patients with previous interstitial lung disease (ILD) were more likely to develop high grade CIP than those without [83.3% (5/6) versus 15.4% (3/15), P = 0.011].The odds ratio (OR) was 32.5 (95% CI 2.284-443.145, P = 0.009). Increased BALF lymphocyte percentage was associated with high grade CIP, OR 1.095 (95% CI 1.001-1.197, P = 0.047), and higher possibility of CIP relapse, OR 1.123 (95% CI, 1.005-1.225, P = 0.040). Lymphocyte subsets were tested in 15 patients. CD4/CD8 > 1 was found in 80% (4/5) of relapsed patients and 20% (2/10) of patients without relapse (P = 0.047). The OR was 16.00 (95% CI 1.093-234.24, P = 0.043). In this retrospective study, patients with previous ILD was more likely to develop high grade CIP. Higher lymphocyte percentage in BALF was associated with high grade CIP and susceptibility to relapse during treatment of CIP. A CD4/CD8 ratio greater than 1 in lymphocyte subsets of BALF was associated with higher possibility of CIP relapse. We found that TBCB is a safe procedure in CIP patients.

A novel technique for conducting flexible bronchoscopy cryobiopsy under conscious sedation: An observational study

Transbronchial lung cryobiopsy (TBCB) is a reliable method for obtaining histopathological findings in interstitial lung diseases. TBCB is traditionally performed during rigid bronchoscopy, positioning an endobronchial balloon blocker to facilitate bleeding management. Therefore, it can be challenging to implement in Centers without access to anesthesiologic support or dedicated beds for endoscopic procedures. We present a series of 11 patients who underwent 12 TBCBs using a flexible bronchoscope and a 5 Fr endobronchial blocker passing through an uncuffed endotracheal tube, under moderate sedation and spontaneous breathing. All procedures were carried out in an endoscopy suite, using fluoroscopy guidance but without requiring anesthesiologic assistance. TBCB was feasible in all cases, and it demonstrated similar or improved diagnostic yield (90.1%) and safety compared to rigid bronchoscopy. In 1 case, it was successfully repeated due to an inconclusive histological definition at the first attempt. The size of the samples was consistent with the literature, as it was the incidence of pneumothorax (16.6%). Four cases of moderate bleeding and 4 cases of severe bleeding were managed without further complications. To our knowledge, this is the first description of a technique allowing to perform TBCB through an artificial airway without need for either rigid bronchoscopy or general anesthesia. We believe this technique could make TBCB faster, cost-effective, and feasible even in resource-limited settings without compromising on safety. However, further studies are needed to validate these findings.

The Diagnostic Efficiency and Safety of Transbronchial Lung Cryobiopsy Using 1.1-mm Cryoprobe in Diagnosing Interstitial Lung Disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is increasingly used to diagnose interstitial lung disease (ILD). The 1.1-mm cryoprobe has recently been available in clinical practice. The diagnostic yield and safety of TBLC using a 1.1-mm cryoprobe need to be confirmed.

METHODS

A prospective, randomized controlled trial was conducted in patients with suspected ILD and randomly assigned to 1.1-mm and 1.9-mm cryoprobe groups. The primary outcome was the diagnostic yield of multidisciplinary discussion. Secondary outcomes were sample quality and incidence of complications. The tension and stress effects during TBLC onto the target lobe caused by 1.1-mm and 1.9-mm cryoprobes were also evaluated using finite element analysis.

RESULTS

A total of 224 patients were enrolled. No significant differences were observed in the diagnostic yield (80.4% vs. 79.5%, p = 0.845) and sample quality scores (5.73 ± 0.64 vs. 5.66 ± 0.77; p = 0.324) between the 1.9-mm cryoprobe group and 1.1-mm cryoprobe group. The average surface areas of samples in 1.1-mm cryoprobe group were smaller, while no difference in sample weights was observed. A decreased incidence of moderate bleeding was found in the 1.1-mm cryoprobe group (17.0% vs. 6.2%, p = 0.027), while there was no difference in the incidence of the pneumothorax, there was a trend to higher rate of pneumothorax in 1.1-mm group. In finite element analysis, the 1.1-mm cryoprobe required the largest tension and produced the largest stress.

CONCLUSION

Compared with a 1.9-mm cryoprobe, there was no difference in specimen quality or diagnostic rate but smaller sample size with a 1.1-mm cryoprobe. There was a decreased risk of moderate bleeding, but a trend towards increased risk for pneumothorax with 1.1-mm cryoprobe.

TRAIL REGISTRATION

Clinicaltrials.gov identifier NCT04047667; registered August 4, 2019.

Case of stage 0 pulmonary sarcoidosis pathologically diagnosed via transbronchial lung cryobiopsy

A 45-year-old male was diagnosed with arrhythmia during a routine health examination. Findings from different modalities, such as echocardiography and radiography, were consistent with cardiac involvement in sarcoidosis. There was no ocular involvement or superficial lymph node enlargement. A chest computed tomography scan did not reveal any pulmonary lesions or bilateral hilar lymphadenopathy. To pathologically diagnose systemic sarcoidosis, transbronchial lung cryobiopsy was performed. Results showed pathological evidence of noncaseating epithelioid granulomas. Herein, we present a case in which sarcoidosis diagnosis was confirmed via transbronchial lung cryobiopsy despite the absence of respiratory lesions on computed tomography scan.

Interstitial Lung Disease: A Review

Importance

Interstitial lung disease (ILD) consists of a group of pulmonary disorders characterized by inflammation and/or fibrosis of the lung parenchyma associated with progressive dyspnea that frequently results in end-stage respiratory failure. In the US, ILD affects approximately 650 000 people and causes approximately 25 000 to 30 000 deaths per year.

Observations

The most common forms of ILD are idiopathic pulmonary fibrosis (IPF), which accounts for approximately one-third of all cases of ILD, hypersensitivity pneumonitis, accounting for 15% of ILD cases, and connective tissue disease (CTD), accounting for 25% of ILD cases. ILD typically presents with dyspnea on exertion. Approximately 30% of patients with ILD report cough. Thoracic computed tomography is approximately 91% sensitive and 71% specific for diagnosing subtypes of ILDs such as IPF. Physiologic assessment provides important prognostic information. A 5% decline in forced vital capacity (FVC) over 12 months is associated with an approximately 2-fold increase in mortality compared with no change in FVC. Antifibrotic therapy with nintedanib or pirfenidone slows annual FVC decline by approximately 44% to 57% in individuals with IPF, scleroderma associated ILD, and in those with progressive pulmonary fibrosis of any cause. For connective tissue disease-associated ILD, immunomodulatory therapy, such as tocilizumab, rituximab, and mycophenolate mofetil, may slow decline or even improve FVC at 12-month follow-up. Structured exercise therapy reduces symptoms and improves 6-minute walk test distance in individuals with dyspnea. Oxygen reduces symptoms and improves quality of life in individuals with ILD who desaturate below 88% on a 6-minute walk test. Lung transplant may improve symptoms and resolve respiratory failure in patients with end-stage ILD. After lung transplant, patients with ILD have a median survival of 5.2 to 6.7 years compared with a median survival of less than 2 years in patients with advanced ILD who do not undergo lung transplant. Up to 85% of individuals with end-stage fibrotic ILD develop pulmonary hypertension. In these patients, treatment with inhaled treprostinil improves walking distance and respiratory symptoms.

Conclusions and Relevance

Interstitial lung disease typically presents with dyspnea on exertion and can progress to respiratory failure. First-line therapy includes nintedanib or pirfenidone for IPF and mycophenolate mofetil for ILD due to connective tissue disease. Lung transplant should be considered for patients with advanced ILD. In patients with ILD, exercise training improves 6-minute walk test distance and quality of life.

Assessment of a randomized controlled trial on the safety of pre-placing bronchial balloons in transbronchial lung cryobiopsy for diagnosing interstitial lung disease

RATIONALE AND OBJECTIVES

Bleeding is a major complication of transbronchial lung cryobiopsy (TBLC), and pre-placing a bronchial balloon is one of the clinical practices used to prevent it, but with very weak evidence, which should be confirmed. This study aimed to conduct whether pre-placing a bronchial balloon in TBLC for diagnosing interstitial lung disease (ILD) is more safety.

MATERIALS AND METHODS

In this prospective, single-center, randomized controlled trial, patients with suspected ILD were enrolled and randomly assigned to pre-placed balloon and none-pre-placed balloon groups. The primary outcome was incidence of moderate bleeding in each group. The secondary endpoints were the incidence of severe bleeding, pneumothorax, and other procedural complications.

RESULTS

Exactly 250 patients were enrolled between August 2019 and March 2022, with 125 in each group. There were no significant differences in severe bleeding between the none-pre-placed balloon group and pre-placed balloon group (1.6% vs. 0.8%; adjusted p = 0.520), while more moderate bleeding occurred in the none-pre-placed balloon group (26.4% vs. 6.4%, adjusted p = 0.001), as well as more use of hemostatic drug (28.0% vs. 6.4%, adjusted p = 0.001). Three patients in the none-pre-placed balloon group used the bronchial balloon. More samples could be acquired in the pre-placed balloon group than in the none-pre-placed balloon group (3.8 ± 0.9 vs. 3.1 ± 0.9, p < 0.001). There were no significant differences in multidisciplinary discussion (MDD) between the two groups (89.6% vs. 91.2%, adjusted p = 0.182).

CONCLUSION

A pre-placed bronchial balloon can reduce the incidence of moderate bleeding and increase the confidence of the bronchoscopists. However, it had no effect on increasing the diagnostic rate of MDD and reducing severe bleeding.

REGISTRATION NUMBER

NCT04047667 ( www.

CLINICALTRIALS

gov identifier).

Defining Optimal Settings for Lung Cryobiopsy in End-Stage Pulmonary Disease. A Human, Ex Vivo, Diseased Lung Clinical Trial

BACKGROUND

To evaluate optimal settings of probe size, freezing time, and distance to the pleura that influence the size and quality of biopsy specimens during transbronchial lung cryobiopsies in ESPD.

METHODS

We prospectively recruited 17 patients undergoing lung transplantation. We created a nonperfused ex vivo bronchoscopy setting to perform multiple cryobiopsies with different probe sizes (1.7, 1.9, and 2.4 mm), freezing times (3, 5, 7, 10, 20, 30 seconds), and probe distance from pleura (5, 10, and 20 mm). Alveolated pulmonary parenchyma area≥50% in histology was considered a good quality biopsy, with a minimum procedural artifact. We used logistic regression to identify independent parameters as risk factors for histologic adequacy.

RESULTS

A total of 545 cryobiopsies were obtained from 34 explanted lungs after pneumonectomy for lung transplantation. The mean maximum diameter of the specimen achieved with the 1.7 probe was larger (13.5 mm) than those obtained with 1.9 and 2.4 mm probes (11.3 and 10.7 mm, P= 0.07). More pleural macroscopic damage and pleural tissue in histology occurred with the 2.4 mm probe ( P <0.001). There was no difference in the quality of specimens between the different freezing times and the distance from the pleura.

CONCLUSIONS

Freezing time and distance from the pleura did not affect the histologic quality for diagnosing ESPD in severely damaged lungs. Smaller cryoprobe size did not negatively affect sample adequacy.

Multidisciplinary Approach to the Diagnosis of Idiopathic Interstitial Pneumonias: Focus on the Pathologist's Key Role

Idiopathic Interstitial Pneumonias (IIPs) are a heterogeneous group of the broader category of Interstitial Lung Diseases (ILDs), pathologically characterized by the distortion of lung parenchyma by interstitial inflammation and/or fibrosis. The American Thoracic Society (ATS)/European Respiratory Society (ERS) international multidisciplinary consensus classification of the IIPs was published in 2002 and then updated in 2013, with the authors emphasizing the need for a multidisciplinary approach to the diagnosis of IIPs. The histological evaluation of IIPs is challenging, and different types of IIPs are classically associated with specific histopathological patterns. However, morphological overlaps can be observed, and the same histopathological features can be seen in totally different clinical settings. Therefore, the pathologist's aim is to recognize the pathologic-morphologic pattern of disease in this clinical setting, and only after multi-disciplinary evaluation, if there is concordance between clinical and radiological findings, a definitive diagnosis of specific IIP can be established, allowing the optimal clinical-therapeutic management of the patient.

The accuracy of electromagnetic navigation bronchoscopy compared to fluoroscopy in navigation of transbronchial lung cryobiopsy in patients with interstitial lung disease

BACKGROUND

Safely implementing transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) requires accurate navigation. Traditional fluoroscopy falls short in reducing the risk of post-procedure pneumothorax. The potential of electromagnetic navigation bronchoscopy (ENB) as a more precise navigation method warrants further exploration.

METHODS

A prospective cohort study was conducted on ILD patients undergoing TBLC. Patients were assigned either fluoroscopy or ENB for cryoprobe positioning. Navigation accuracy was evaluated using cone beam computed tomography (CBCT) images as the standard. Safety and diagnostic yield were also observed.

RESULTS

Seventeen patients underwent TBLC, with 10 guided by fluoroscopy and seven by ENB. Fluoroscopy-guided cryoprobe navigation required more adjustments [9/15 (60%) v.s. 1/9 (11%), p = 0.018] for subsequent TBLC compared to ENB, as confirmed by CBCT images. Clinical characteristics, post-procedure complications, and biopsy specimen size showed no significant differences between the groups. Fourteen patients obtained a pathological diagnosis, and 15 received a multidisciplinary discussion (MDD) diagnosis. In the fluoroscopy group, three patients failed to obtain a pathological diagnosis, and two failed to obtain an MDD diagnosis.

CONCLUSIONS

ENB demonstrates significantly superior accuracy in TBLC navigation compared to traditional fluoroscopy when CBCT images are used as a reference. Further studies are necessary to determine the value of ENB in TBLC navigation for ILD patients.

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.

Selective bronchial occlusion for the prevention of pneumothorax after transbronchial lung cryobiopsy in a pulmonary alveolar proteinosis patient: a case report

The diagnosis of pulmonary alveolar proteinosis (PAP) is based on biopsies. Compared with other methods of taking biopsies, transbronchial lung cryobiopsy (TBLC) has a higher diagnostic rate and the likelihood of pneumothorax. Selective bronchial occlusion (SBO) is an effective technique for treating intractable pneumothorax. However, there are no data available about SBO for the prevention of pneumothorax after TBLC in a PAP patient. A 49-year-old man complained of recurrent cough and tachypnea, and his symptoms did not fully resolve until the diagnosis was confirmed, and he was treated with whole lung lavage. Our patient was ultimately diagnosed with PAP by TBLC but not multiple tests for the bronchoalveolar lavage fluid (BALF). The patient was discharged quickly after whole lung lavage due to the fact that he did not develop pneumothorax under SBO. This case illustrates that TBLC is a supplementary examination for PAP, especially for those in whom BALF results fail to confirm a diagnosis. Moreover, our report highlights that SBO is necessary to effectively prevent pneumothorax during and after multiple TBLCs in PAP patients.

Transbronchial lung cryobiopsy for peripheral pulmonary lesions. A narrative review

An increasing number of peripheral pulmonary lesions (PPLs) requiring tissue verification to establish a definite diagnosis for further individualized management are detected due to the growing adoption of lung cancer screening by chest computed tomography (CT), especially low-dose CT. However, the morphological diagnosis of PPLs remains challenging. Transbronchial lung cryobiopsy (TBLC) that can retrieve larger specimens with more preserved cellular architecture and fewer crush artifacts in comparison with conventional transbronchial forceps biopsy (TBFB), as an emerging technology for diagnosing PPLs, has been demonstrated to have the potential to resolve the clinical dilemma pertaining to currently available sampling devices (e.g., forceps, needle and brush) and become a diagnostic cornerstone for PPLs. Of note, with the introduction of the 1.1 mm cryoprobe that will be more compatible with advanced bronchoscopic navigation techniques, such as radial endobronchial ultrasound (r-EBUS), virtual bronchoscopic navigation (VBN) and electromagnetic navigation bronchoscopy (ENB), the use of TBLC is expected to gain more popularity in the diagnosis of PPLs. While much remains for exploration using the TBLC technique for diagnosing PPLs, it can be envisaged that the emergence of additional studies with larger data accrual will hopefully add to the body of evidence in this field.

Pulmonary Langerhans cell histiocytosis diagnosed using transbronchial lung cryobiopsy: A case report

A 63-year-old Japanese woman with multiple cysts in both lungs on chest computed tomography (CT) was referred to our hospital after a thorough examination, including a transbronchial lung biopsy (TBLB), failed to provide a diagnosis. Based on the findings on chest CT and pathological examination of the bronchoalveolar lavage fluid and transbronchial lung cryobiopsy (TBLC) specimen, the patient was diagnosed with pulmonary Langerhans cell histiocytosis (PLCH). TBLC may replace TBLB as the main diagnostic technique for PLCH, although further studies are required to determine the usefulness of TBLC for the diagnosis of PLCH.

Utility and Safety of Bronchoscopic Cryotechniques-A Comprehensive Review

Cryosurgical techniques are employed for diagnostic and therapeutic bronchoscopy and serve as important tools for the management of pulmonary diseases. The diagnosis of interstitial lung disease requires multidisciplinary team discussions after a thorough assessment of history, physical exam, computed tomography, and lung-function testing. However, histological diagnosis is required in selected patients. Surgical lung biopsy has been the gold standard but this can be associated with increased morbidity and mortality. Transbronchial lung cryobiopsy is an emerging technique and multiple studies have shown that it has a high diagnostic yield with a good safety profile. There is wide procedural variability and the optimal technique for cryobiopsy is still under investigation. There is emerging data that demonstrate that cryobiopsy is safe and highly accurate in the diagnosis of thoracic malignancies. Furthermore, cryorecanalization procedures are a useful adjunct for the palliation of tumors in patients with central airway obstruction. One should keep in mind that these procedures are not free from complications and should be carried out in a specialized center by a trained and experienced bronchoscopy team. We present a review of the literature on the diagnostic and therapeutic utility of bronchoscopy-guided cryosurgical procedures and their safety profile.

Transbronchial Cryobiopsy Is Superior to Forceps Biopsy for Diagnosing both Fibrotic and Non-Fibrotic Interstitial Lung Diseases

BACKGROUND

Interstitial lung disease (ILD) evaluation often requires lung biopsy for definite diagnosis. In recent years, transbronchial cryobiopsy (TBCB) emerged as a procedure with higher diagnostic yield than transbronchial forceps biopsy (TBFB), especially for fibrotic ILDs. Nonetheless, studies comparing these modalities in non-fibrotic ILDs and for specific ILD diagnoses are scarce.

OBJECTIVES

The aim of this study was to evaluate the diagnostic yield and safety of TBCB and TBFB in patients with fibrotic and non-fibrotic ILDs.

METHOD

An observational retrospective multicenter study including patients with ILD diagnosis by multidisciplinary discussion that underwent TBCB or TBFB between 2017 and 2021. Chest CT scans were reviewed by a chest radiologist. Biopsy specimens were categorized as diagnostic (with specific histological pattern), nondiagnostic, or without lung parenchyma. Nondiagnostic samples were reassessed by a second lung pathologist. TBCB and TBFB diagnostic yields were analyzed by multivariate regression. Procedural complications were evaluated as well.

RESULTS

276 patients were included, 116 (42%) underwent TBCB and 160 (58%) TBFB. Fibrotic ILDs were present in 148 patients (54%). TBCB diagnostic yield was 78% and TBFB 48% (adjusted odds ratio [AOR] 4.2, 95% CI: 2.4-7.6, p < 0.01). The diagnostic yield of TBCB was higher than TBFB among patients with fibrotic ILD (AOR 3.8, p < 0.01), non-fibrotic ILD (AOR 5.8, p < 0.01), and across most ILD diagnoses. TBCB was associated with higher risk for significant bleeding (10% vs. 3%, p < 0.01), but similar risk for pneumothorax.

CONCLUSIONS

Diagnostic yield of TBCB was superior to that of TBFB for both fibrotic and non-fibrotic ILDs, and across most diagnoses.

The Evolving Concept of the Multidisciplinary Approach in the Diagnosis and Management of Interstitial Lung Diseases

BACKGROUND

Interstitial lung diseases (ILDs) are a group of heterogeneous diseases characterized by inflammation and/or fibrosis of the lung interstitium, leading to a wide range of clinical manifestations and outcomes. Over the years, the literature has demonstrated the increased diagnostic accuracy and confidence associated with a multidisciplinary approach (MDA) in assessing diseases involving lung parenchyma. This approach was recently emphasized by the latest guidelines from the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Association for the diagnosis of ILDs.

METHODS

In this review, we will discuss the role, composition, and timing of multidisciplinary diagnosis (MDD) concerning idiopathic pulmonary fibrosis, connective tissue disease associated with ILDs, hypersensitive pneumonia, and idiopathic pneumonia with autoimmune features, based on the latest recommendations for their diagnosis.

RESULTS

The integration of clinical, radiological, histopathological, and, often, serological data is crucial in the early identification and management of ILDs, improving patient outcomes. Based on the recent endorsement of transbronchial cryo-biopsy in idiopathic pulmonary fibrosis guidelines, an MDA helps guide the choice of the sampling technique, obtaining the maximum diagnostic performance, and avoiding the execution of more invasive procedures such as a surgical lung biopsy. A multidisciplinary team should include pulmonologists, radiologists, pathologists, and, often, rheumatologists, being assembled regularly to achieve a consensus diagnosis and to review cases in light of new features.

CONCLUSIONS

The literature highlighted that an MDA is essential to improve the accuracy and reliability of ILD diagnosis, allowing for the early optimization of therapy and reducing the need for invasive procedures. The multidisciplinary diagnosis of ILDs is an ongoing and dynamic process, often referred to as a "working diagnosis", involving the progressive integration and re-evaluation of clinical, radiological, and histological features.

Transbronchial Lung Cryobiopsy and Surgical Lung Biopsy: A Prospective Multi-Centre Agreement Clinical Trial (CAN-ICE)

Rationale: Transbronchial cryobiopsy (TBCB) for the diagnosis of interstitial lung disease (ILD) has shown promising results, but prospective studies with matched surgical lung biopsy (SLB) have yielded conflicting results. Objectives: We aimed to assess within- and between-center diagnostic agreement between TBCB and SLB at both the histopathologic and multidisciplinary discussion (MDD) levels in patients with diffuse ILD. Methods: In a multicenter prospective study, we performed matched TBCB and SLB in patients referred for SLB. After a blinded review by three pulmonary pathologists, all cases were reviewed by three independent ILD teams in an MDD. MDD was performed first with TBCB, then with SLB in a second session. Within-center and between-center diagnostic agreement was evaluated using percentages and correlation coefficients. Measurements and Main Results: Twenty patients were recruited and underwent contemporaneous TBCB and SLB. Within-center diagnostic agreement between TBCB-MDD and SLB-MDD was reached in 37 of the 60 (61.7%) paired observations, resulting in a Cohen's κ value of 0.46 (95% confidence interval [CI], 0.29-0.63). Diagnostic agreement increased among high-confidence or definitive diagnoses on TBCB-MDD (21 of 29 [72.4%]), but not significantly, and was more likely among cases with SLB-MDD diagnoses of idiopathic pulmonary fibrosis than fibrotic hypersensitivity pneumonitis (13 of 16 [81.2%] vs. 16 of 31 [51.6%]; P = 0.047). Between-center agreement for cases was markedly higher for SLB-MDD (κ = 0.71 [95% CI, 0.52-0.89]) than TBCB-MDD (κ = 0.29 [95% CI, 0.09-0.49]). Conclusions: This study demonstrated moderate TBCB-MDD and SLB-MDD diagnostic agreement for ILD, while between-center agreement was fair for TBCB-MDD and substantial for SLB-MDD. Clinical trial registered with www.clinicaltrials.gov (NCT02235779).

The Characteristic of Transbronchial Lung Cryobiopsy in the Pathological Diagnosis of Hypersensitivity Pneumonitis

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) has widely used for the diagnosis of diffuse lung disease. However, it remains unclear whether TBLC is useful for the diagnosis in hypersensitivity pneumonitis (HP).

METHODS

We investigated 18 patients who underwent TBLC and were diagnosed with HP based on pathology or multidisciplinary discussion (MDD). Of the 18 patients, 12 had fibrotic HP (fHP), 2 had non-fibrotic HP (non-fHP) diagnosed with MDD. The remaining 4 patients were diagnosed with fHP by pathology but not by MDD because of clinical features. The radiology and pathology of these cases were compared.

RESULTS

All patients with fHP showed radiological findings of inflammation, fibrosis, and airway disease. Conversely, pathology showed fibrosis and inflammation in 11 of 12 cases (92%), but airway disease was significantly less common with 5 cases (42%) (p = 0.014). Non-fHP showed inflammatory cell infiltration mainly in the centrilobule on pathology, which was consistent with radiology. Granulomas were found in 5 patients with HP (36%). In the non-HP group, airway-centered interstitial fibrosis was observed in 3 patients (75%) with pathology.

CONCLUSIONS

The pathology with TBLC is difficult to evaluate airway disease of HP. We need to understand this characteristic of TBLC to make a MDD diagnosis of HP.

Histologic Analysis of Idiopathic Pulmonary Fibrosis by Morphometric and Fractal Analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrotic lung disorder, ultimately leading to respiratory failure and death. Despite great research advances in understanding the mechanisms underlying the disease, its diagnosis, and its treatment, IPF still remains idiopathic without known biological or histological markers able to predict disease progression or response to treatment. The histologic hallmark of IPF is usual interstitial pneumonia (UIP), with its intricate architectural distortion and temporal inhomogeneity. We hypothesize that normal lung alveolar architecture can be compared to fractals, such as the Pythagoras tree with its fractal dimension (D_f), and every pathological insult, distorting the normal lung structure, could result in D_f variations. In this study, we aimed to assess the UIP histologic fractal dimension in relationship to other morphometric parameters in newly diagnosed IPF patients and its possible role in the prognostic stratification of the disease. Clinical data and lung tissue specimens were obtained from twelve patients with IPF, twelve patients with non-specific interstitial pneumonia (NSIP), and age-matched "healthy" control lung tissue from patients undergoing lung surgery for other causes. Histology and histomorphometry were performed to evaluate D_f and lacunarity measures, using the box counting method on the FracLac ImageJ plugin. The results showed that D_f was significantly higher in IPF patients compared to controls and fibrotic NSIP patients, indicating greater architectural distortion in IPF. Additionally, high D_f values were associated with higher fibroblastic foci density and worse prognostic outcomes in IPF, suggesting that D_f may serve as a potential novel prognostic marker for IPF. The scalability of D_f measurements was demonstrated through repeated measurements on smaller portions from the same surgical biopsies, which were selected to mimic a cryobiopsy. Our study provides further evidence to support the use of fractal morphometry as a tool for quantifying and determining lung tissue remodeling in IPF, and we demonstrated a significant correlation between histological and radiological D_f in UIP pattern, as well as a significant association between D_f and FF density. Furthermore, our study demonstrates the scalability and self-similarity of D_f measurements across different biopsy types, including surgical and smaller specimens.

Transbronchial lung cryobiopsy and pulmonary fibrosis: A never-ending story?

Background

The diagnostic process of pulmonary fibrosis (PF) is often challenging, requires a collaborative effort of several experts, and often requires bioptic material, which can be difficult to obtain, both in terms of quality and technique. The main procedures available to obtain such samples are transbronchial lung cryobiopsy (TBLC) and surgical lung biopsy (SLB).

Objective

The purpose of this paper is to review the evidence for the role of TBLC in the diagnostic-therapeutic process of PF.

Methods

A comprehensive review was performed to identify articles to date that addressed the role of TBLC in the diagnostic-therapeutic process of PF using the PubMed® database.

Results

The reasoned search identified 206 papers, including 21 manuscripts (three reviews, one systematic review, two guidelines, two prospective studies, three retrospective studies, one cross-sectional study, one original article, three editorials, three clinical trials, and two unclassifiable studies), which were included in the final review.

Conclusions

TBLC is gaining increasing efficacy and improving safety profile; however, there are currently no clear data demonstrating its superiority over SLB. Therefore, the two techniques should be considered with careful rationalization on a case-by-case basis. Further research is needed to further optimize and standardize the procedure and to thoroughly study the histological and molecular characteristics of PF.

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

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

Diagnosis and Pharmacologic Management of Fibrotic Interstitial Lung Disease

Interstitial lung disease is an umbrella term that encompasses a spectrum of parenchymal lung pathologies affecting the gas exchanging part of the lung. While many of these disease entities are not fibrotic in nature, a number can lead to pulmonary fibrosis which may or may not progress over time. Idiopathic pulmonary fibrosis is the prototypical, progressive fibrotic interstitial lung disease, which can lead to worsening hypoxemic respiratory failure and mortality within a number of years from the time of diagnosis. The importance of an accurate and timely diagnosis of interstitial lung diseases, which is needed to inform prognosis and guide clinical management, cannot be overemphasized. Developing a consensus diagnosis requires the incorporation of a variety of factors by a multidisciplinary team, which then may or may not determine a need for tissue sampling. Clinical management can be challenging given the heterogeneity of disease behavior and the paucity of controlled trials to guide decision making. This review addresses current paradigms and recent updates in the diagnosis and pharmacologic management of these fibrotic interstitial lung diseases.

Ultrathin bronchoscopic cryobiopsy of peripheral pulmonary lesions

BACKGROUND AND OBJECTIVE

Ultrathin bronchoscopy aids in the diagnosis of peripheral pulmonary lesions. However, both the working channel and the specimens are small. A 1.1-mm ultrathin cryoprobe that can enter the working channel of the ultrathin bronchoscope is now available, which may overcome the limitations of small specimen size. The aim of this study was to evaluate the feasibility, efficacy and safety of ultrathin bronchoscopic cryobiopsy using an ultrathin cryoprobe for diagnosing peripheral pulmonary lesions.

METHODS

Patients with peripheral pulmonary lesions ≤30 mm in diameter were prospectively enrolled in the study. All patients underwent forceps biopsy followed by cryobiopsy using a 3.0-mm ultrathin bronchoscope under radial probe endobronchial ultrasound guidance, virtual bronchoscopic navigation and fluoroscopic guidance. The primary endpoint was the feasibility of cryobiopsy.

RESULTS

In total, 50 patients with peripheral pulmonary lesions were enrolled in the study; the median longest diameter on computed tomography was 17.9 mm. Cryobiopsy was performed successfully in 49 patients (98%). Forceps biopsy, cryobiopsy and the combination of these two methods provided a specific diagnosis in 54% (27/50), 62% (31/50) and 74% (37/50) of patients, respectively. The median size of specimens obtained via cryobiopsy was significantly larger than the median size obtained via forceps biopsy (7.0 vs. 1.3 mm² , respectively, p < 0.001). Mild bleeding during cryobiopsy occurred in 47 patients (94%). No moderate/severe bleeding or pneumothorax occurred.

CONCLUSION

Ultrathin bronchoscopic cryobiopsy is feasible, effective and sufficiently safe for the diagnosis of peripheral pulmonary lesions.

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.

Novel diagnostic techniques in interstitial lung disease

Research into novel diagnostic techniques and targeted therapeutics in interstitial lung disease (ILD) is moving the field toward increased precision and improved patient outcomes. An array of molecular techniques, machine learning approaches and other innovative methods including electronic nose technology and endobronchial optical coherence tomography are promising tools with potential to increase diagnostic accuracy. This review provides a comprehensive overview of the current evidence regarding evolving diagnostic methods in ILD and to consider their future role in routine clinical care.

Diagnosing interstitial lung disease by multidisciplinary discussion: A review

The multidisciplinary meeting (MDM) has been endorsed in current international consensus guidelines as the gold standard method for diagnosis of interstitial lung disease (ILD). In the absence of an accurate and reliable diagnostic test, the agreement between multidisciplinary meetings has been used as a surrogate marker for diagnostic accuracy. Although the ILD MDM has been shown to improve inter-clinician agreement on ILD diagnosis, result in a change in diagnosis in a significant proportion of patients and reduce unclassifiable diagnoses, the ideal form for an ILD MDM remains unclear, with constitution and processes of ILD MDMs varying greatly around the world. It is likely that this variation of practice contributes to the lack of agreement seen between MDMs, as well as suboptimal diagnostic accuracy. A recent Delphi study has confirmed the essential components required for the operation of an ILD MDM. The ILD MDM is a changing entity, as it incorporates new diagnostic tests and genetic markers, while also adapting in its form in response to the obstacles of the COVID-19 pandemic. The aim of this review was to evaluate the current evidence regarding ILD MDM and their role in the diagnosis of ILD, the practice of ILD MDM around the world, approaches to ILD MDM standardization and future directions to improve diagnostic accuracy in ILD.

Applications of cryobiopsy in airway, pleural, and parenchymal disease

INTRODUCTION

:Cryobiopsy is a novel diagnostic technique for thoracic diseases which has been extensively investigated over the past 20 years. It was originally proposed for the diagnosis of endobronchial lesions and diffuse parenchymal lung disease due to limitations of conventional sampling techniques including small size and presence of artifacts.

AREAS COVERED

:We will review recent evidence related to the expanding use of cryobiopsy in thoracic diseases. To identify references, the MEDLINE database was searched from database inception until May 2022 for case series, cohort studies, randomized controlled trials, systematic reviews and meta-analyses related to cryobiopsy.

EXPERT OPINION

Cryobiopsy has expanding applications in the field of thoracic diseases. Evidence to support transbronchial cryobiopsy as an alternative to surgical lung biopsy is increasing and was recently endorsed as a conditional recommendation by the latest American Thoracic Society guideline update for Idiopathic Pulmonary Fibrosis. Developments in technology and technique, in particular the availability of a 1.1 mm flexible cryoprobe, have extended applications to pulmonary diseases, including diagnosis of interstitial lung diseases, peripheral pulmonary lesions, and lung transplant rejection.