Before Freezing Out Cryobiopsy, We Need to Thaw Out Flaws in the Diagnosis of Interstitial Lung Disease

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.

Practical application and validation of the 2018 ATS/ERS/JRS/ALAT and Fleischner Society guidelines for the diagnosis of idiopathic pulmonary fibrosis

Background

Accurate diagnosis of idiopathic pulmonary fibrosis (IPF) is essential to inform prognosis and treatment. In 2018, the ATS/ERS/JRS/ALAT and Fleischner Society released new diagnostic guidelines for usual interstitial pneumonitis (UIP)/IPF, adding Probable UIP as a CT category based on prior studies demonstrating this category had relatively high positive predictive value (PPV) for histopathologic UIP/Probable UIP. This study applies the 2018 ATS/ERS/JRS/ALAT and Fleischner Society guidelines to determine test characteristics of CT categories in academic clinical practice.

Methods

CT and histopathology were evaluated by three thoracic radiologists and two thoracic pathologists. Comparison of consensus categorization by the 2018 ATS and Fleischner Society guidelines by CT and histopathology was performed.

Results

Of patients with CT UIP, 87% (PPV, 95% CI: 60–98%) had histopathologic UIP with 97% (CI: 90–100%) specificity. Of patients with CT Probable UIP, 38% (PPV, CI: 14–68%) had histopathologic UIP and 46% (PPV, CI: 19–75%) had either histopathologic UIP or Probable UIP, with 88% (CI: 77–95%) specificity. Patients with CT Indeterminate and Alternative Diagnosis had histopathologic UIP in 27% (PPV, CI: 6–61%) and 21% (PPV, CI: 11–33%) of cases with specificities of 90% (CI: 80–96%) and 25% (CI: 16–37%). Interobserver variability (kappa) between radiologists ranged 0.32–0.81.

Conclusions

CT UIP and Probable UIP have high specificity for histopathologic UIP, and CT UIP has high PPV for histopathologic UIP. PPV of CT Probable UIP was 46% for combined histopathologic UIP/Probable UIP. Our results indicate that additional studies are needed to further assess and refine the guideline criteria to improve classification performance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01670-7.

Transbronchial Cryobiopsy in the Diagnosis of Fibrotic Interstitial Lung Disease

CONTEXT.—

Transbronchial cryobiopsy is an emerging procedure to obtain lung tissue for diagnosis of interstitial lung disease and has gained popularity because it is less invasive and has a lower rate of complications compared with nonselective surgical lung biopsy.

OBJECTIVE.—

To provide an overview of the status of the medical literature regarding transbronchial cryobiopsy.

DATA SOURCES.—

A literature search was performed using PubMed search engine. The terms "cryobiopsy" or "cryoprobe" and "interstitial lung disease" or "diffuse parenchymal lung disease" or "pulmonary fibrosis" were used, with the search concluding at the end of November 2019.

CONCLUSIONS.—

While the diagnostic yield of transbronchial cryobiopsy is slightly lower than surgical lung biopsy, a growing amount of literature suggests that with a multidisciplinary approach cryobiopsy provides diagnostic and prognostic information approaching that of surgical lung biopsy with lower morbidity and mortality.

Transbronchial Cryobiopsy in Interstitial Lung Diseases: State-of-the-Art Review for the Interventional Pulmonologist

Interstitial lung diseases are a heterogenous group of disorders that are often difficult to diagnose precisely. Clinical, laboratory, radiographic, and histologic information may be needed to arrive at the correct diagnosis. The multidisciplinary discussion has been proven to be useful in this patient group. Transbronchial cryobiopsy has become a popular method for obtaining tissue samples. Over the course of the last decade, there has been a significant amount of research assessing the feasibility, safety, and diagnostic endpoints of transbronchial cryobiopsy in patients with interstitial lung disease. Data continues to mount to support its use, which has been reflected in guidelines and expert panel reports. Patient selection, procedural performance, and appropriate specimen handling are critical factors for success. A coordinated approach by pulmonologists with expertise in interstitial lung diseases, interventional pulmonologists, and thoracic pathologists is essential. In this evidence-based narrative review, we address transbronchial cryobiopsies from these three distinct perspectives. In addition, the current literature was used to address nine common procedural questions.

Lung cryobiopsy and interstitial lung disease: What is its role in the era of multidisciplinary meetings and antifibrotics?

Diagnosing ILD can be complex, and despite detailed evaluation and HRCT imaging, many patients require lung biopsy to help classify their disease. SLB has served as the reference standard for histopathology in ILD, since initial classification schemes were created more than 50 years ago. Frequently, patients are too unwell to undertake SLB and remain unclassifiable, despite the input of expert MDD. This can limit access to therapy and establishment of prognosis. TBLC is an emerging procedure for sampling lung tissue with promising results in research and clinical settings. Although diagnostic yield is not as high as SLB, the risk profile looks to be more acceptable and the accuracy appears to be good. There is increasing evidence for the utility of cryobiopsy in ILD diagnosis, particularly within the MDD. Cryobiopsy serves as an important adjunct for the diagnosis of ILD, enhancing the diagnostic confidence of treating clinicians.

Lung Cryobiopsy for the Diagnosis of Interstitial Lung Diseases: A Series Contribution to a Debated Procedure

Introduction: Transbronchial cryobiopsy is an alternative to surgical biopsy for the diagnosis of fibrosing interstitial lung diseases, although the role of this relatively new method is rather controversial. Aim of this study is to evaluate the diagnostic performance and the safety of transbronchial cryobiopsy in patients with fibrosing interstitial lung disease. Materials and methods: The population in this study included patients with interstitial lung diseases who underwent cryobiopsy from May 2015 to May 2018 at the Division of Pneumology of San Giuseppe Hospital in Milan and who were retrospectively studied. All cryobiopsy procedures were performed under fluoroscopic guidance using a flexible video bronchoscope and an endobronchial blocking system in the operating room with patients under general anaesthesia. The diagnostic performance and safety of the procedure were assessed. The main complications evaluated were endobronchial bleeding and pneumothorax. All cases were studied with a multidisciplinary approach, before and after cryobiopsy. Results: Seventy-three patients were admitted to this study. A specific diagnosis was reached in 64 cases, with a diagnostic sensitivity of 88%; 5 cases (7%) were considered inadequate, 4 cases (5%) were found to be non-diagnostic. Only one major bleeding event occurred (1.4%), while 14 patients (19%) experienced mild/moderate bleeding events while undergoing bronchoscopy; 8 cases of pneumothorax (10.9%) were reported, of which 2 (2.7%) required surgical drainage. Conclusions: When performed under safe conditions and in an experienced center, cryobiopsy is a procedure with limited complications having a high diagnostic yield in fibrotic interstitial lung disease.