Determining factors of endobronchial ultrasound-guided transbronchial needle aspiration specimens for lung cancer subtyping and molecular testing

Pulmonary endoscopy - central to an interventional pulmonology program

INTRODUCTION

Pulmonary endoscopy occupies a central role in Interventional Pulmonology and is frequently the mainstay of diagnosis of respiratory disease, in particular lung malignancy. Older techniques such as rigid bronchoscopy maintain an important role in central airway obstruction. Renewed interest in the peripheral pulmonary nodule is driving major advances in technologies to increase the diagnostic accuracy and advance new potential endoscopic therapeutic options.

AREAS COVERED

This paper describes the role of pulmonary endoscopy, in particular ultrasound in the diagnosis and staging of lung malignancy. We will explore the recent expansion of ultrasound to include endoscopic ultrasound - bronchoscopy (EUS-B) and combined ultrasound (CUS) techniques. We will discuss in detail the advances in the workup of the peripheral pulmonary nodule.We performed a non-systematic, narrative review of the literature to summarize the evidence regarding the indications, diagnostic yield, and safety of current bronchoscopic sampling techniques.

EXPERT OPINION

EBUS/EUS-B has revolutionized the diagnosis and staging of thoracic malignancy resulting in more accurate assessment of the mediastinum compared to mediastinoscopy alone, thus reducing the rate of futile thoracotomies. Although major advances in the assessment of the peripheral pulmonary nodule have been made, the role of endoscopy in this area requires further clarification and investigation.

Acquisition and Handling of Endobronchial Ultrasound Transbronchial Needle Samples: An American College of Chest Physicians Clinical Practice Guideline

BACKGROUND

Endobronchial ultrasound-guided transbronchial aspiration (EBUS-TBNA) has become the standard for initial lung cancer diagnosis and staging. Previous guidelines have generally focused on the "when" and "how" of EBUS-TBNA; however, little guidance is available on handling and processing specimens during and after acquisition to help optimize both diagnostic yield and tissue integrity for ancillary studies. This document examines the available literature on EBUS-TBNA specimen processing and handling.

STUDY DESIGN AND METHODS

Rigorous methodology was applied to provide a trustworthy evidence-based guideline and expert panel report. Panelists developed key clinical questions utilizing the Population, Intervention, Comparator, and Outcome (PICO) format, addressing specific topics in EBUS-TBNA specimen processing. MEDLINE (via PubMed) and the Cochrane Library were systematically searched to identify relevant literature, supplemented by manual searches. References were screened for inclusion with document evaluation tools to assess the quality of included studies, extract meaningful data, and grade the level of evidence to support each recommendation or suggestion.

RESULTS

Our systematic review and critical analysis of the literature of the 9 PICO questions related to handling and processing EBUS-TBNA specimens resulted in 9 evidence-based statements.

INTERPRETATION

Evidence of the handling and processing of EBUS-TBNA specimens varies in strength but is satisfactory in some areas to guide clinicians in certain aspects of specimen handling. Additional research in many aspects of specimen handling and processing is needed to help improve our knowledge base.

Clinical Applications of Endobronchial Ultrasound (EBUS) Scope: Challenges and Opportunities

Endobronchial Ultrasound (EBUS) has been widely used to stage lung tumors and to diagnose mediastinal diseases. In the last decade, this procedure has evolved in several technical aspects, with new tools available to optimize tissue sampling and to increase its diagnostic yield, like elastography, different types of needles and, most recently, miniforceps and cryobiopsy. Accordingly, the indications for the use of the EBUS scope into the airways to perform the Endobronchial Ultrasound-TransBronchial Needle Aspiration (EBUS-TBNA) has also extended beyond the endobronchial and thoracic boundaries to sample lesions from the liver, left adrenal gland and retroperitoneal lymph nodes via the gastroesophageal tract, performing the Endoscopic UltraSound with Bronchoscope-guided Fine Needle Aspiration (EUS-B-FNA). In this review, we summarize and critically discuss the main indication for the use of the EBUS scope, even the more uncommon, to underline its utility and versatility in clinical practice.

High SUVmax Is an Independent Predictor of Higher Diagnostic Accuracy of ROSE in EBUS-TBNA for Patients with NSCLC

Introduction: This study aimed to verify the predictors of the diagnostic accuracy of rapid on-site evaluation (ROSE) in endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) among patients with non-small cell lung cancer (NSCLC). Methods: We retrospectively reviewed consecutive patients with NSCLC who underwent EBUS-TBNA for staging or diagnosis at our hospital from June 2016 to June 2018. The patients were divided into two groups—those with a correct diagnosis and an incorrect diagnosis after ROSE. Kaplan−Meier plots and log-rank tests were used to estimate outcomes. Results: A total of 84 patients underwent EBUS-TBNA for staging and diagnosis. Sixty patients with demonstrated malignant mediastinal lymph nodes were enrolled. In the univariate analysis, lymph nodes < 1.5 cm (HR = 3.667, p = 0.031) and a SUVmax > 5 (HR = 41, p = 0.001) were statistically significant for diagnostic accuracy of ROSE. In the multivariate Cox regression analysis, only a SUVmax > 5 (HR = 20.258, p = 0.016) was statistically significant. Conclusions: A SUVmax > 5 is an independent predictor of higher diagnostic accuracy of ROSE in EBUS-TBNA in patients with NSCLC with malignant mediastinal lymph nodes. Therefore, ROSE in patients with a SUVmax < 5 might not be reliable and requires further prudent assessment (more shots or repeated biopsies at mediastinal LNs) in clinical practice.

Evaluation of lung cancer biomarkers profile for the decision of targeted therapy in EBUS-TBNA cytological samples

BACKGROUND

Guidelines recommend performing biomarker tests for epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), BRAF and ROS proto-oncogene-1(ROS1) genes and protein expression of programmed death ligand-1(PD-L1) in patients with non-small lung cell carcinoma (NSCLC). Studies reported that endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) can provide sufficient material for cancer biomarker analyses, but there are still concerns about the subject.

AIM

The purpose of the study was to assess the adequacy of EBUS-TBNA for testing lung cancer biomarkers.

METHODS

We retrospectively reviewed patients with NSCLC whose EBUS-TBNA was analysed for EGFR, ALK, ROS-1, BRAF and PD-L1 expression between December 2011 and December 2020.

RESULTS

A total of 394 patients were enrolled in the study. EGFR mutation and ALK fusion were the most common studied biomarkers. EBUS-TBNA adequacy rate for biomarker tests was found 99.0% for EGFR, 99.1 for ALK, 97.2% for ROS1, 100% for BRAF and 99.3% for PD-L1 testing. Multivariate analysis revealed the histological type, history of treatment for NSCL, size, or 18-fluorodeoxyglucose uptake of sampled lesion did not show any association with TBNA adequacy for biomarker testing.

CONCLUSION

EBUS-TBNA can provide adequate material for biomarker testing for EGFR, ALK, ROS-1, BRAF and PD-L1 expression.

Detection of short stature homeobox 2 and RAS-associated domain family 1 subtype A DNA methylation in interventional pulmonology

One of the most important aspects of interventional pulmonology is to obtain tissue or liquid samples of the chest to diagnose a respiratory disease; however, it is still possible to obtain insufficient tissue or cytologic specimens. Indeed, methylation detection is an effective method by which to establish a diagnosis. This review focuses on the clinical application of short stature homeobox 2 and RAS-associated domain family 1 subtype A DNA methylation detection in interventional pulmonology, including bronchoscopic fluid biopsy, transbronchial needle aspiration, and pleural effusion.

Pilot Study of the Performance of 19-G Needle in Endobronchial Ultrasound-guided Transbronchial Aspiration for the Diagnosis and Testing of Molecular Markers in Lung Cancer

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become the standard for diagnosis and staging of lung cancer. Historically, 21- and 22-G needles have been paired with EBUS. We evaluated the performance of EBUS-TBNA using a larger 19-G needle in the assessment of tumor tissue obtained and success of testing for molecular markers.

METHODS

We prospectively enrolled adult patients with lymphadenopathy concerning for metastatic lung cancer. Patients underwent diagnostic EBUS-TBNA utilizing 19-G needles. Cases of non-small cell lung cancer (NSCLC) were evaluated for programmed cell death receptor ligand (PD-L1) expression. Cases of adenocarcinoma or undifferentiated NSCLC were further evaluated for 3 molecular markers for driver mutations: epidermal growth factor receptor (EGFR), c-ros oncogene 1 (ROS-1), and anaplastic lymphoma kinase (ALK).

RESULTS

Fifty patients were enrolled and underwent EBUS-TBNA using 19-G needles. PD-L1 assay was successfully performed in 90% of NSCLC cases. In adenocarcinoma or undifferentiated NSCLC cases, the success rate in testing was 90% for EGFR and 86% for ALK. ROS-1 testing had a success rate of 67%; 24% of these specimens had adequate tumor cells but there was technical difficulty with the assay. Block quality was judged by total number of tumor cells per hematoxylin and eosin-stained slide of each cell block (58% of specimens had >500 cells and 22% had 200 to 500 cells). There were no adverse events.

CONCLUSION

EBUS-TBNA using 19-G needles can obtain a high number of tumor cells and has a high rate of success in performing assays for PD-L1, EGFR, and ALK in NSCLC patients without an increase in adverse events. The success rate of ROS-1 testing was lower.

The Morphological Analysis of Cells in the Bronchoscopic Brushing and TBNA of Patients with Lung Adenocarcinoma

Biopsy, brushing, and transbronchial needle aspiration (TBNA) are the most common methods for diagnosis of lung adenocarcinoma and are taken during the same diagnostic bronchoscopic procedure. However, it is not clear what the morphological diagnostic criteria of cytology by brushing or TBNA are. A retrospective analysis was performed on 136 patients who underwent video bronchoscopy examination for diagnostic purposes. All the subjects were performed brushing or TBNA and confirmed as lung adenocarcinoma by biopsy or postoperative pathology. An additional 140 randomly selected patients with benign lung diseases were included in the study and used as a control group. The benign cells usually confused with adenocarcinoma cells were ciliated columnar cells, mucous columnar cells, ciliated cuboid cells, and reactive ciliated cells, respectively. The number of cases diagnosed as adenocarcinoma cells, carcinoma cells, suspicious cancer cells, and atypical proliferative cells by cytology was 101, 11, 20, and 4, respectively. The main basis for the interpretation of adenocarcinoma cells is the enlargement of individual nucleus, the arrangements of multistage papillary, and the general enlargement of nuclei, while the main clue for the interpretation of suspicious cancer cells and dysplasia cells comes from escape cells. The results suggested that the degree of nuclear enlargement, multiple papillary arrangement, and escape cells or escape trend cells are important clues for the interpretation of lung adenocarcinoma cells, while the atypical proliferative cells were similar to escape cells or escape trend cells, which were essentially benign cells beside the cancer.

Recent advances in convex probe endobronchial ultrasound: a narrative review

Convex probe endobronchial ultrasound (CP-EBUS) has been widely used in the lymph node staging and restaging of lung tumors and the diagnosis of mediastinal diseases. Recent years have seen continuous progress in this technology. For diagnosis, elastography technology can preliminarily distinguish between benign and malignant lesions, so that reduce the number of punctures. CP-EBUS can also be used as an endoscopic ultrasound (EUS) to guide needle aspirations of liver lesions, retroperitoneal lymph nodes and left adrenal gland (LAG) lesions sometimes. Some advances help diagnosing more accurately and effectively, such as the intranodal forceps biopsy (IFB), the new type of 22G needle, the rapid on-site evaluation (ROSE) and the cancer gene methylation, etc. In addition, special advances are being made in diagnosis using artificial intelligence (AI). For treatment, CP-EBUS has yielded novel research results when applied to transbronchial needle injection (TBNI) and radioactive seed implantation in clinical cases, and blocking of the cardiac plexus in animal studies. The next-generation CP-EBUS is also ready for use in the clinic and the technology will be improving continuously. Through this review, we hope to educate clinicians on the latest uses of CP-EBUS and open up further research ideas for readers interested in this technology.

Accuracy of endoscopic ultrasound-guided needle aspiration specimens for molecular diagnosis of non-small-cell lung carcinoma

BACKGROUND

Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) are highly sensitive for diagnosing and staging lung cancer. In recent years, targeted therapy has shown great significance in the treatment of non-small cell lung carcinoma (NSCLC). Using these minimally invasive techniques to obtain specimens for molecular testing will provide patients with a more convenient diagnostic approach.

AIM

To evaluate the feasibility and accuracy of tissue samples obtained using EUS-FNA and EBUS-TBNA for molecular diagnosis of NSCLC.

METHODS

A total of 83 patients with NSCLC underwent molecular testing using tissues obtained from EUS-FNA or EBUS-TBNA at the Tianjin Medical University Cancer Hospital from January 2017 to June 2019. All enrolled patients underwent chest computed tomography or positron emission tomography/computed tomography prior to puncture. We detected abnormal expression of EGFR, KRAS, MET, HER2, ROS1 and anaplastic lymphoma kinase protein. Two patients failed to complete molecular testing due to insufficient tumor tissue. The clinical features, puncture records, molecular testing results and targeted treatment in the remaining 81 patients were summarized.

RESULTS

In a total of 99 tissue samples obtained from 83 patients, molecular testing was successfully completed in 93 samples with a sample adequacy ratio of 93.9% (93/99). Biopsy samples from two patients failed to provide test results due to insufficient tumor tissue. In the remaining 81 patients, 62 cases (76.5%) were found to have adenocarcinoma, 11 cases (13.6%) had squamous cell carcinoma, 3 cases (3.7%) had adenosquamous carcinoma and 5 cases (6.2%) had NSCLC-not otherwise specified. The results of molecular testing showed EGFR mutations in 21 cases (25.9%), KRAS mutations in 9 cases (11.1%), ROS-1 rearrangement in 1 case (1.2%) and anaplastic lymphoma kinase-positive in 5 cases (6.2%). Twenty-four patients with positive results received targeted therapy. The total effectiveness rate of targeted therapy was 66.7% (16/24), and the disease control rate was 83.3% (20/24).

CONCLUSION

Tissue samples obtained by EUS-FNA or EBUS-TBNA are feasible for the molecular diagnosis of NSCLC and can provide reliable evidence for clinical diagnosis and treatment.

Radiomics model for distinguishing tuberculosis and lung cancer on computed tomography scans

BACKGROUND

Pulmonary tuberculosis (TB) and lung cancer (LC) are common diseases with a high incidence and similar symptoms, which may be misdiagnosed by radiologists, thus delaying the best treatment opportunity for patients.

AIM

To develop and validate radiomics methods for distinguishing pulmonary TB from LC based on computed tomography (CT) images.

METHODS

We enrolled 478 patients (January 2012 to October 2018), who underwent preoperative CT screening. Radiomics features were extracted and selected from the CT data to establish a logistic regression model. A radiomics nomogram model was constructed, with the receiver operating characteristic, decision and calibration curves plotted to evaluate the discriminative performance.

RESULTS

Radiomics features extracted from lesions with 4 mm radial dilation distances outside the lesion showed the best discriminative performance. The radiomics nomogram model exhibited good discrimination, with an area under the curve of 0.914 (sensitivity = 0.890, specificity = 0.796) in the training cohort, and 0.900 (sensitivity = 0.788, specificity = 0.907) in the validation cohort. The decision curve analysis revealed that the constructed nomogram had clinical usefulness.

CONCLUSION

These proposed radiomic methods can be used as a noninvasive tool for differentiation of TB and LC based on preoperative CT data.