Molecular analysis of small tissue samples obtained via transbronchial lung biopsy using radial probe endobronchial ultrasound

Invasive Diagnostic Procedures from Bronchoscopy to Surgical Biopsy-Optimization of Non-Small Cell Lung Cancer Samples for Molecular Testing

Background and Objectives: Treatment of advanced lung cancer (LC) has become increasingly personalized over the past decade due to an improved understanding of tumor molecular biology and antitumor immunity. The main task of a pulmonologist oncologist is to establish a tumor diagnosis and, ideally, to confirm the stage of the disease with the least invasive technique possible. Materials and Methods: The paper will summarize published reviews and original papers, as well as published clinical studies and case reports, which studied the role and compared the methods of invasive pulmonology diagnostics to obtain adequate tumor tissue samples for molecular analysis, thereby determining the most effective molecular treatments. Results: Bronchoscopy is often recommended as the initial diagnostic procedure for LC. If the tumor is endoscopically visible, the biopsy sample is susceptible to molecular testing, the same as tumor tissue samples obtained from surgical resection and mediastinoscopy. The use of new sampling methods, such as cryobiopsy for peripheral tumor lesions or cytoblock obtained by ultrasound-guided transbronchial needle aspiration (TBNA), enables obtaining adequate small biopsies and cytological samples for molecular testing, which have until recently been considered unsuitable for this type of analysis. During LC patients' treatment, resistance occurs due to changes in the mutational tumor status or pathohistological tumor type. Therefore, the repeated taking of liquid biopsies for molecular analysis or rebiopsy of tumor tissue for new pathohistological and molecular profiling has recently been mandated. Conclusions: In thoracic oncology, preference should be given to the least invasive diagnostic procedure providing a sample for histology rather than for cytology. However, there is increasing evidence that, when properly processed, cytology samples can be sufficient for both the cancer diagnosis and molecular analyses. A good knowledge of diagnostic procedures is essential for LC diagnosing and treatment in the personalized therapy era.

NSCLC in the Era of Targeted and Immunotherapy: What Every Pulmonologist Must Know

The treatment of non-small cell lung cancer has dramatically changed over the last decade through the use of targeted therapies and immunotherapies. Implementation of these treatment regimens relies on detailed knowledge regarding each tumor’s specific genomic profile, underscoring the necessity of obtaining superior diagnostic tissue specimens. While these treatment approaches are commonly utilized in the metastatic setting, approval among earlier-stage disease will continue to rise, highlighting the importance of early and comprehensive biomarker testing at the time of diagnosis for all patients. Pulmonologists play an integral role in the diagnosis and staging of non-small cell lung cancer via sophisticated tissue sampling techniques. This multifaceted review will highlight current indications for the use of targeted therapies and immunotherapies in non-small cell lung cancer and will outline the quality of various diagnostic approaches and subsequent success of tissue biomarker testing. Pulmonologist-specific methods, including endobronchial ultrasound and guided bronchoscopy, will be examined as well as other modalities such as CT-guided transthoracic biopsy and more.

Proposal of a novel pipeline involving precise bronchoscopy of distal peripheral pulmonary lesions for genetic testing

Next-generation sequencing (NGS) has become increasingly more important for lung cancer management. We now expect biopsies to be sensitive, safe, and yielding sufficient samples for NGS. In this study, we propose ultraselective biopsy (USB) with sample volume adjustment (SVA) as a novel method that integrates an ultrathin bronchoscope, radial probe endobronchial ultrasound, and the direct oblique method for ultraselective navigation, and adjustment of sample volume for NGS. Our purpose was to estimate the diagnostic potential and the applicability of USB-SVA for amplicon-based NGS analysis. The diagnostic yield of bronchoscopy in forty-nine patients with malignant peripheral pulmonary lesions (PPLs) was retrospectively analyzed, and amplicon-based NGS analysis was performed on samples from some patients using USB. The diagnostic yields of distal PPLs in the USB group were significantly higher than those in the non-USB group (90.5% vs. 50%, respectively, p = 0.015). The extracted amounts of nucleic acids were at least five times the minimum requirement and the sequence quality met the criteria for the Oncomine™ Target Test. Only the tumor cell content of some samples was insufficient. The feasibility of the pipeline for USB, SVA, and amplicon-based NGS in distal PPLs was demonstrated.

Radial-EBUS and virtual bronchoscopy planner for peripheral lung cancer diagnosis: How it became the first-line endoscopic procedure

Background

Various advanced bronchoscopy methods have been developed to reach peripheral lung lesions (PLL). In a large cohort, we aimed to assess a standardized procedure of first‐line radial‐endobronchial ultrasound (r‐EBUS) and virtual bronchoscopy planner for the diagnosis of peripheral lung cancer.

Methods

This retrospective, single center study included patients who had r‐EBUS‐guided bronchoscopy for the diagnosis of a PLL between 2008 and 2019. Cases without a final diagnosis of cancer or follow‐up were excluded.

Results

Between 2008 and 2019, 2735 patients had a r‐EBUS procedure, among whom 1627 had a final diagnosis of cancer and were included in the present study. Over the 12‐year study period, r‐EBUS became the first‐line endoscopic procedure to assess PLL (25% as first‐line bronchoscopy in 2008 vs. 92% in 2019). The frequency of the bronchus sign decreased from 2009 to 2019 (100% to 80%; p = 0.001), whereas US visualization of the lesion remained stable (88%). The median number of biopsies increased from two (2008 to 2014) to four (2015 to 2019) (p < 0.0001), with the same diagnostic efficiency (74% total and 80% when a bronchus sign was present). Of the 651 adenocarcinomas, molecular analysis was possible in 86%. PD‐L1 expression analysis was possible in 81% of cases. During the study period, the lifetime of the radial probe increased from 57 procedures to 77 procedures/probe.

Conclusion

Because r‐EBUS and VB planner is easy to perform under local anesthesia, inexpensive and efficient it can be used as a first‐line procedure to assess peripheral lung cancer.

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.

Comparison of radial endobronchial ultrasound-guided transbronchial lung biopsy with distance measurement versus with guide sheath in diagnosing peripheral pulmonary lesions with a diameter ≥3 cm by thin bronchoscope

OBJECTIVE:

This study aims to explore the diagnostic values of radial endobronchial ultrasound-guided transbronchial lung biopsy with distance (rEBUS-D-TBLB) measurement and with guide sheath (rEBUS-GS-TBLB) for peripheral pulmonary lesions (PPLs) with a diameter ≥3 cm by thin bronchoscope.

PATIENTS AND METHODS:

Six hundred and three patients with PPL (diameter ≥3 cm) were enrolled in this study. The subjects were divided into the rEBUS-D-TBLB and rEBUS-GS-TBLB groups by the random number table method. Patients were assigned to undergo rEBUS-D-TBLB or rEBUS-GS-TBLB, respectively. The histopathology, positive diagnosis rates, duration of the procedure, and postoperative adverse effects between the two groups were examined.

RESULTS:

A total of 569 patients were included in this study according to the inclusion and exclusion criteria, with 282 cases in the rEBUS-D-TBLB group and 287 cases in the rEBUS-GS-TBLB group. For malignant diseases, the positive diagnosis rates of PPL in the outer/inner-middle lung bands and the right-upper/-lower lung lobes by rEBUS-D-TBLB were noninferior to those of rEBUS-GS-TBLB. The duration of the procedure of rEBUS-D-TBLB was longer than that of rEBUS-GS-TBLB. There were 14 cases of hemorrhage >50 mL, 1 case of postoperative chest pain in the rEBUS-D-TBLB group, and 3 cases of hemorrhage >50 mL in the rEBUS-GS-TBLB group.

CONCLUSION:

REBUS-D-TBLB by thin bronchoscope has a high diagnostic value for PPL with a diameter ≥3 cm, which may be considered a useful alternative for rEBUS-GS-TBLB in the clinic.

Guide sheath versus non-guide sheath method for endobronchial ultrasound-guided biopsy of peripheral pulmonary lesions: A multicenter randomized trial

INTRODUCTION

Guide sheaths (GSs) have been widely used during radial probe endobronchial ultrasound-guided transbronchial biopsy (rEBUS-TBB) of peripheral pulmonary lesions. However, it remains unknown whether a GS enhances the diagnostic yield. We compared the diagnostic yields of small peripheral pulmonary lesions between rEBUS-TBB with and without a GS.

METHODS

In eight institutions, patients with peripheral pulmonary lesions≤30 mm in diameter were enrolled and randomized to undergo rEBUS-TBB with a GS (GS group) or without a GS (non-GS group) using a 4.0-mm thin bronchoscope, virtual bronchoscopic navigation, and fluoroscopy. The primary endpoint was the diagnostic yield of the histology specimens.

RESULTS

A total of 605 patients were enrolled; ultimately, data on 596 (300 in the GS group and 296 in the non-GS group) with peripheral pulmonary lesions having a longest median diameter of 19.6 mm were analyzed. The diagnostic yield of histological specimens from the GS group was significantly higher than that from the non-GS group (55.3% versus 46.6%, respectively; p=0.033). Interactions were evident between the diagnostic yields, procedures, lobar locations (upper lobe versus other regions, p=0.003), and lesion texture (solid versus part-solid nodules, p=0.072).

CONCLUSIONS

The diagnostic yield for small peripheral pulmonary lesions afforded by rEBUS-TBB using a GS was higher than that without a GS.

Bronchoscopic tissue yield for advanced molecular testing: are we getting enough?

The treatment of advanced lung cancer has become increasingly personalized over the past decade as a result of the improved understanding of tumor molecular biology and anti-tumor immunity. An adequate tumor sample is central to targetable mutation analysis, and immunologic profiling. The majority of lung cancer patients currently present at an advanced disease stage, so that diagnosis and staging are largely based on small biopsy and cytology specimens. Flexible bronchoscopy techniques play a prominent role in the acquisition of these diagnostic specimens. This narrative review summarizes the available evidence with regards to the role of various conventional and advanced flexible bronchoscopy techniques in acquiring sufficient tissue for mutation analysis and programmed death-ligand 1 (PD-L1) testing.