Bronchoscopic modalities to diagnose sarcoidosis

Role of Bronchoscopy in Diagnosis of Sarcoidosis

Sarcoidosis is a multisystem inflammatory disorder with unclear etiology and can often pose a diagnostic challenge. A tissue diagnosis is often necessary to illustrate the non-caseating granulomas on histopathology. This review aims to synthesize current evidence related to tissue diagnosis of sarcoidosis using various bronchoscopic techniques. We start by discussing standard bronchoscopic techniques which have remained the cornerstone of diagnostic workup such as bronchoalveolar lavage (BAL), endobronchial biopsy (EBB), conventional transbronchial needle aspiration (cTBNA) and transbronchial lung biopsy (TBLB) followed by newer modalities that incorporate real-time image guidance using endobronchial and endoscopic ultrasound. Although BAL, EBB, and TBLB have been employed as a diagnostic tool for several decades, their sensitivity and diagnostic yield is inferior to ultrasound-based endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). More recently, convincing evidence has also emerged to support the diagnostic accuracy and tissue yield of transbronchial lung cryobiopsy which will also be discussed in this review. These advances in bronchoscopic equipment and techniques over the last 2 decades have made it possible to obtain tissue samples using minimally invasive techniques thus avoiding invasive open lung biopsy and the risks that inherently follow. Up-to-date knowledge of these modalities is imperative for ensuring evidence-based medicine and improving patient-centric outcomes.

High-Definition Videobronchoscopy for the Diagnosis of Airway Involvement in Sarcoidosis: The Enhance Sarcoidosis Multicenter Study

BACKGROUND

The ability of high-definition (HD) videobronchoscopy to detect airway involvement in sarcoidosis has not been evaluated previously.

RESEARCH QUESTION

What is the role of HD videobronchoscopy in the identification of sarcoidosis-associated airway abnormalities (AAs)? What are the patterns of AAs more commonly observed and more frequently associated with the detection of granulomas in endobronchial biopsy (EBB)?

STUDY DESIGN AND METHODS

In this prospective international multicenter cohort study, consecutive patients with suspected sarcoidosis underwent airway inspection with an HD videobronchoscope and EBB using a standardized workflow. AAs were classified according to six patterns defined a priori: nodularity, cobblestoning, thickening, plaque, increased vascularity, and miscellaneous. We assessed diagnostic yield of EBB, prevalence of AAs, and interobserver agreement for different patterns of AAs.

RESULTS

AAs were identified in 64 of 134 patients with sarcoidosis (47.8%), with nodularity (n = 23 [17.2%]), plaque (n = 19 [14.2%]), and increased vascularity (n = 19 [14.2%]) being the most prevalent. The diagnostic yield of EBB was 36.6%. AAs were significantly more prevalent in patients with than in those without nonnecrotizing granulomas on EBB (67.4% vs 36.5%; P = .001). Likewise, parenchymal disease on CT scan imaging was significantly more common in patients with than in those without nonnecrotizing granulomas on EBB (79.6% vs 54.1%; P = .003). On a per-lesion analysis, nonnecrotizing granulomas were seen especially in EBB samples obtained from areas of cobblestoning (9/10 [90%]) and nodularity (17/29 [58.6%]). The overall diagnostic yield of random EBB was low (31/134 [23.1%]). The interobserver agreement for the different patterns of AA was fair (Fleiss κ = 0.34).

INTERPRETATION

In a population with a large prevalence of White Europeans, HD videobronchoscopy detected AAs in approximately one-half of patients with sarcoidosis. The diagnostic yield of EBB was higher in patients with parenchymal involvement on CT scan imaging and in those with AAs, especially if manifesting as cobblestoning and nodularity.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT4743596; URL: www.

CLINICALTRIALS

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Diagnostic value of exfoliated tumor cells combined with DNA methylation in bronchoalveolar lavage fluid for lung cancer

BACKGROUND

To evaluate the diagnostic value of exfoliated tumor cells (ETCs) numbers combined with DNA methylation levels in bronchoalveolar lavage fluid (BALF) in lung cancer.

METHODS

BALF samples were collected from 43 patients with lung cancer and 23 with benign lung disease. ETCs were detected by the nano-enrichment method, and the methylation status of the short stature homeobox gene 2 (SHOX2) and the RAS association domain family 1, isoform A (RASSF1A) gene were detected by RT-PCR. The diagnostic value of each metric was evaluated by receiver operating characteristic curve analysis, specificity and sensitivity.

RESULTS

The sensitivity/specificity of RASSF1A and SHOX2 methylation detection were 44.12%/76.47% and 93.75%/87.50%, respectively. When "RASSF1A/SHOX2 methylation" was used as a positive result, the sensitivity increased to 88.24%, and the specificity decreased to 81.25%. When "RASSF1A + SHOX methylation" was used as positive, the sensitivity was reduced to 32.35%, but the specificity was increased to 100.00%. The sensitivity and specificity of ETCs detection in BALF were 89.47% and 16.67%, respectively. When "SHOX2/RASSF1A methylation + ETCs was used as a positive result, the sensitivity and specificity of the detection were 79.31% and 81.82%, respectively. When "SHOX2 + RASSF1A + ETCs" was used as positive, the sensitivity was 34.48% and the specificity was 90.91%. Receiver operating characteristic curve analysis showed that when SHOX2, RASSF1A methylation and ETCs were combined, the diagnostic sensitivity increased to 0.778.

CONCLUSION

ETCs counting in combination with SHOX2 and RASSF1A methylation assays in BALF samples has demonstrated excellent sensitivity for lung cancer diagnosis and is an effective complementary tool for clinical diagnosis of lung cancer.

The Risk of Sarcoidosis Misdiagnosis and the Harmful Effect of Corticosteroids When the Disease Picture Is Incomplete

Sarcoidosis is a complex granulomatous disease of unknown etiology. Due to the heterogeneity of the disease, the diagnosis remains challenging in many cases, often at the physician's discretion, requiring a thorough and complex investigation. Many other granulomatous diseases have the potential to mimic sarcoidosis, whether infectious, occupational, or autoimmune diseases and starting an unnecessary corticosteroid treatment can worsen the patient's prognosis, leading to side effects that can be harder to treat than the actual disease.

Diagnostic Yield of Transbronchial Lung Cryobiopsy Compared to Transbronchial Forceps Biopsy in Patients with Sarcoidosis in a Prospective, Randomized, Multicentre Cross-Over Trial

Background: Transbronchial lung forceps biopsy (TBLF) is of limited value for the diagnosis of interstitial lung disease (ILD). However, in cases with predominantly peribronchial pathology, such as sarcoidosis, TBLF is considered to be diagnostic in most cases. The present study examines whether transbronchial lung cryobiopsy (TBLC) is superior to TBLF in terms of diagnostic yield in cases of sarcoidosis. Methods: In this post hoc analysis of a prospective, randomized, controlled, multicentre study, 359 patients with ILD requiring diagnostic bronchoscopic tissue sampling were included. TBLF and TBLC were both used for each patient in a randomized order. Histological assessment was undertaken on each biopsy and determined whether sarcoid was a consideration. Results: A histological diagnosis of sarcoidosis was established in 17 of 272 cases for which histopathology was available. In 6 out of 17 patients, compatible findings were seen with both TBLC and TBLF. In 10 patients, where the diagnosis of sarcoidosis was confirmed by TBLC, TBLF did not provide a diagnosis. In one patient, TBLF but not TBLC confirmed the diagnosis of sarcoidosis. Conclusions: In this post hoc analysis, the histological diagnosis of sarcoidosis was made significantly more often by TBLC than by TBLF. As in other idiopathic interstitial pneumonias (IIPs), the use of TBLC should be considered when sarcoidosis is suspected.

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.

Diagnostic yield and safety of transbronchial cryobiopsy in sarcoidosis

Introduction

Transbronchial lung cryobiopsy (TBLC) is an endoscopic technique proven to be useful in diagnostic approach to interstitial lung disease (ILD), but its role in sarcoidosis is not fully established. The aim of the present study was to assess the diagnostic yield of TBLC in sarcoidosis and its safety profile.

Methods

Retrospective analysis of patients, evaluated in a tertiary hospital ILD outpatient clinic, who underwent TBLC in the diagnostic work-up. TBLC was performed in accordance with the 2018 expert statement from the Cryobiopsy Working Group.

Results

32 patients were included (mean±sd age 47.7±12.6 years, 59.4% male) and divided into three groups: highly likely sarcoidosis (n=21), possible sarcoidosis (n=6) and unlikely sarcoidosis (n=5). A mean of 2.8±0.8 TBLCs were performed. The definitive diagnosis was established by TBLC in 20 out of 27 patients with suspected sarcoidosis. Two patients were diagnosed with sarcoidosis by other methods performed afterwards. TBLC leaded to other diagnosis as well, such as fungal infection (n=1), hypersensitivity pneumonitis (n=1) and silicosis (n=3), making the diagnostic yield for suspected sarcoidosis of TBLC of 92.6%. TBLC was also able to show compatible histological features in five patients whom sarcoidosis was not previously considered. The complications reported overall were pneumothorax in five (15.6%) patients and moderate bleeding in one (3.1%) case.

Conclusion

In this cohort, TBLC was a safe, reliable and useful procedure in sarcoidosis diagnosis. These results suggest that TBLC can be used successfully in those cases where a definitive diagnosis could not be reached with the usual and less-invasive diagnostic tools.

TBLC is a safe procedure with a high diagnostic yield in patients with a prior suspicion of sarcoidosis. Moreover, it can diagnose atypical cases in which previous methods are inconclusive.http://bit.ly/2KWJxLG

Role of Bronchoscopic Techniques in the Diagnosis of Thoracic Sarcoidosis

The diagnosis of sarcoidosis relies on clinical and radiological presentation, evidence of non-caseating granulomas in histopathology and exclusion of alternative causes of granulomatous inflammation. Currently, a proper diagnosis, with a high level of confidence, is considered as key to the appropriate diagnosis and management of the disease. In this sense, this review aims to provide a brief overview on the role of bronchoscopy in the diagnosis of thoracic sarcoidosis, incorporating newer techniques to establish, including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), transesophageal ultrasound-guided needle aspiration with the use of an echo bronchoscope (EUS-B-FNA) and transbronchial lung cryobiopsy (TBLC). Most of the literature reports the diagnostic superiority of endosonographic techniques, such as EBUS-TBNA alone or in combination with EUS-FNA, over conventional bronchoscopic modalities in diagnosing Scadding stages I and II of the disease. Moreover, TBLC may be considered a useful and safe diagnostic tool for thoracic sarcoidosis, overcoming some limitations of transbronchial lung biopsy (TBLB), avoiding more invasive modalities and being complementary to endosonographic procedures such as EBUS-TBNA.

The complimentary role of transbronchial lung cryobiopsy and endobronchial ultrasound fine needle aspiration in the diagnosis of sarcoidosis

PURPOSE

Transbronchial lung cryobiopsy (TBLC) is a novel technique that has proved to be useful in diagnosing various interstitial lung diseases (ILD). The use of TBLC to diagnose sarcoidosis in an unselected patient population is unknown, and could be complimentary to endobronchial ultrasound fine needle aspiration (EBUS-FNA).

METHODS

A retrospective analysis of 36 patients in a single, tertiary-care, academic medical center was conducted to describe the yield of both EBUS-FNA and TBLC in the diagnosis of suspected sarcoidosis over a three year period. A grading system to evaluate the presence and extent of specific radiographic features on computed tomography chest imaging studies was compared to the results of EBUS-FNA and TBLC. Complications associated with the procedures were also noted.

RESULTS

The overall diagnostic yield in our cohort (all pathologic diagnosis considered) was 80.6% (29 out of 36 patients had a definite pathologic diagnosis). Eighteen patients referred for possible sarcoidosis had a positive bronchoscopic specimen confirming the diagnosis of sarcoidosis. For those patients with a pathologic diagnosis of sarcoidosis, the diagnostic yield for EBUS-FNA and TBLC was 66.7% each (12 out of 18 patients), while the combined diagnostic yield for EBUS-FNA and TBLC increased to 100%. For all cases, the pneumothorax rate was 11.1%.

CONCLUSIONS

TBLC appears to be a safe and complimentary technique to diagnose sarcoidosis and could be considered part of the diagnostic armamentarium in bronchoscopic centers.