Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)-from morphology to molecular testing

Current role of cytopathology in the molecular and computational era: The perspective of young pathologists

Cytopathology represents a well established diagnostic approach because of its limited cost, reliability, and minimal invasiveness with respect to other methodologies. The evolving complexity of the different classifications systems and the implementation of ancillary techniques to refine the diagnosis is progressively helping in the risk of malignancy stratification, and the adoption of next-generation sequencing techniques contributes to enrich this valuable tool with predictive information, which is always more essential in the tailored medicine era. The recent introduction of digital and computational pathology is further boosting the potentialities of cytopathology, aiding in the interpretation of samples to improve the cost effectiveness of large screening programs and the diagnostic efficiency within intermediate/atypical categories. Moreover, the adoption of artificial intelligence tools is promising to complement molecular investigations, representing a stimulating perspective in the cytopathology field. In this work, the authors tried to summarize the multifaceted nature of this complex and evolving field of pathology, synthesizing the most recent advances and providing the young pathologists' perspective on this fascinating world.

Analysis of variation of serum CEA, SCC, CYFRA21-1 in patients with lung cancer and their diagnostic value with EBUS-TBNA

Background

To explore the variation of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1), and squamous cell carcinoma (SCC) antigen in patients with lung cancer (LC) and their diagnostic value with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA).

Methods

This study examined the diagnostic value of serum tumor marker testing and EBUS-TBNA joint detection for LC in 150 patients with suspected LC.

Results

Compared to benign patients, the serum levels of CYFRA21-1, SCC, and CEA in LC were higher (P<0.05). In patients with squamous cell carcinoma (LSCC), small cell lung cancer (SCLC), and lung adenocarcinoma, lung adenocarcinoma had higher serum CEA levels (P<0.05). In comparison, LSCC patients had higher serum SCC and CYFRA21-1 levels (P<0.05). As compared to each index detected alone, the AUC of combined detection of each index to diagnose LC and identify pathological types of LC was elevated.

Conclusions

The clinical significance of serum CYFRA21-1, SCC, and CEA conjugated with EBUS-TBNA is demonstrated for diagnostic purposes and identification of LC pathological types.

[EBUS-guided cryobiopsy in the diagnosis of mediastinal lesions - step by step]

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the gold standard in the diagnosis of mediastinal and hilar lesions. For certain purposes, such as the diagnosis and subtyping of lymphoproliferative disorders or molecular pathology, a larger amount of intact sample material is required. EBUS cryobiopsy is a new and efficient tool for this purpose. As it is a new approach, there is still no standardised workflow. In this review, we present the procedure step by step as it is performed at the Ruhrlandklinik in Essen.

Endobronchial Ultrasound Guided Transbronchial Needle Aspiration and Next Generation Sequencing Yields

PURPOSE

The use of endobronchial ultrasound (EBUS) is standard practice for lung cancer diagnosis and staging. Next generation sequencing (NGS) for detection of genetic alterations is recommended in advanced, non-squamous, non-small-cell lung cancer (NSCLC). Existing protocols for NGS testing are minimal and reported yields vary. This study aimed to determine the yield of EBUS samples obtained for NGS using a sampling protocol at our institution and assess predictive factors to form collection protocols.

METHODS

We reviewed EBUS bronchoscopies from 2016 to 2021 with non-squamous NSCLC diagnoses. For target lesions suspected to be malignant, the sampling protocol was: (a) two slides for on-site evaluation, (b) three to five fine needle aspirations rinsed into saline for immunohistochemical staining and in-house molecular markers, and (c) additional three to five rinses for NGS. Sufficiency for NGS processing was determined by the pathology department.

RESULTS

Two hundred and seventy-eight non-squamous NSCLC samples were obtained by EBUS (205 adenocarcinoma; 73 not otherwise specified). EBUS was performed under general anesthesia in 75.5% of cases. The overall sample adequacy for NGS testing was 57.5%. Higher adequacy rates were observed when protocol was adhered to 66.0% versus 37.2% (p < 0.001). There was no statistically significant difference based on the size of the lesion or location of the sample.

CONCLUSION

When a protocol of three to five dedicated needle rinses for NGS was followed, we nearly doubled our sample adequacy rate for NSG as compared to standard care. Studies are needed to determine the ideal collection and processing modality to preserve tissue samples for genetic sequencing.

A Review of Endobronchial-Ultrasound-Guided Transbronchial Intranodal Forceps Biopsy and Cryobiopsy

Benign and malignant mediastinal lesions are not infrequently encountered in clinical practice. Mediastinoscopy has long been considered the gold standard in evaluating mediastinal pathology. Since its introduction into clinical practice, endobronchial-ultrasonography-guided transbronchial fine needle aspiration (EBUS-TBNA) has replaced mediastinoscopy as the initial procedure of choice to evaluate mediastinal lesions and to stage lung cancer. Its diagnostic yield in benign mediastinal lesions and less common malignancies, however, has remained limited. This has led different proceduralists to investigate additional procedures to improve the diagnostic yield of EBUS-TBNA. In recent years, different published reports concluded that the addition of EBUS-guided intranodal forceps biopsy (IFB) and transbronchial cryobiopsy (TBCB) to EBUS-TBNA increases the diagnostic yield especially in benign mediastinal lesions and uncommon mediastinal malignancies. The purpose of this review is to describe how EBUS-IFB and EBUS-TBCB are performed, to compare their diagnostic yields, and to discuss their limitations and their potential complications. In addition, the review will conclude with a proposed algorithm on how to incorporate EBUS-IFB and EBUS-TBCB into clinical practice.

Insufficient endobronchial ultrasound-guided transbronchial needle aspiration specimens. When and why? The analysis of criteria and reasons behind the insufficient specimens

BACKGROUND

The classification terminology systems for pulmonary cytology specimens have recently emerged. Inadequate samples, classified as "nondiagnostic," raise challenges in determining the threshold of cell numbers and the risk of malignancy (ROM).

METHODS

The study retrospectively reviewed 248 endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) samples: 46 insufficient samples, 60 low cellularity samples, and 142 adequate samples. Characteristics as cellularity, number of benign and malignant cells, and background features were assessed. Receiver operating characteristic curve analysis was performed to establish cell sufficiency thresholds for the diagnosis.

RESULTS

Out of the 248 samples analyzed, 108 were classified as benign, 94 as malignant, and 46 as insufficient. The study found that the cellularity thresholds for diagnosis in cell blocks and cytological samples were ≥50 cells and ≥100 cells, respectively. The thresholds for tumor cell counts were ≥1 - 10 cells for both types of cells, respectively. Considerably, some low cellularity samples were initially classified as insufficient despite meeting the diagnostic thresholds upon revision. The ROM varied across sample categories, with insufficient samples having a ROM of 10.9%, benign samples 15.7%, suspicious samples 92.0%, and malignant samples 100%.

CONCLUSION

Insufficient EBUS-TBNA samples raise challenges in diagnosis and management. This study identified the root cause of insufficient samples, including factors related to humans, diagnostic methods, sampling, and laboratory processing. By understanding the root causes, diagnostic recommendations can be developed to improve the diagnostic process. The findings emphasize the importance of standardized classification and terminology systems for clear communication among healthcare professionals and institutions, ultimately improving patient care and enabling quality assurance measures.

Evaluation of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) Samples from Advanced Non-Small Cell Lung Cancer for Whole Genome, Whole Exome and Comprehensive Panel Sequencing

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is often the only source of tumor tissue from patients with advanced, inoperable lung cancer. EBUS-TBNA aspirates are used for the diagnosis, staging, and genomic testing to inform therapy options. Here we extracted DNA and RNA from 220 EBUS-TBNA aspirates to evaluate their suitability for whole genome (WGS), whole exome (WES), and comprehensive panel sequencing. For a subset of 40 cases, the same nucleic acid extraction was sequenced using WGS, WES, and the TruSight Oncology 500 assay. Genomic features were compared between sequencing platforms and compared with those reported by clinical testing. A total of 204 aspirates (92.7%) had sufficient DNA (100 ng) for comprehensive panel sequencing, and 109 aspirates (49.5%) had sufficient material for WGS. Comprehensive sequencing platforms detected all seven clinically reported tier 1 actionable mutations, an additional three (7%) tier 1 mutations, six (15%) tier 2-3 mutations, and biomarkers of potential immunotherapy benefit (tumor mutation burden and microsatellite instability). As expected, WGS was more suited for the detection and discovery of emerging novel biomarkers of treatment response. WGS could be performed in half of all EBUS-TBNA aspirates, which points to the enormous potential of EBUS-TBNA as source material for large, well-curated discovery-based studies for novel and more effective predictors of treatment response. Comprehensive panel sequencing is possible in the vast majority of fresh EBUS-TBNA aspirates and enhances the detection of actionable mutations over current clinical testing.

Sotorasib after immune checkpoint inhibitor administration induces hepatotoxicity. True, false or just another adverse effect of NSCLC treatment

Non-small cell lung cancer is still diagnosed at a late disease stage and systematic therapy is necessary. Currently we have three main treatment modalities; chemotherapy, targeted with tyrosine kinase inhibitors and immune check point inhibitors. In the recent years and based on new studies we can administer combination of chemotherapy and immunotherapy, or radiotherapy and immunotherapy. Every treatment approach is based on the specific gene expression of the tumor. Tyrosine kinase inhibitors have been used for more than a decade for epidermal growth factor positive tumors, the same for anaplastic lymphoma kinase and proto-oncogene 1. Programmed death-ligand 1 expression has been found to be associated with the efficiency of immune checkpoint inhibitors. However; there are still several subpopulations in non-small cell lung cancer patients. We will comment on the group with KRAS G12C mutation and the targeted therapy with sotorasib for its efficiency and toxicity based on new studies.

Deep Learning Using Endobronchial-Ultrasound-Guided Transbronchial Needle Aspiration Image to Improve the Overall Diagnostic Yield of Sampling Mediastinal Lymphadenopathy

Lung cancer is the biggest cause of cancer-related death worldwide. An accurate nodal staging is critical for the determination of treatment strategy for lung cancer patients. Endobronchial-ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has revolutionized the field of pulmonology and is considered to be extremely sensitive, specific, and secure for lung cancer staging through rapid on-site evaluation (ROSE), but manual visual inspection on the entire slide of EBUS smears is challenging, time consuming, and worse, subjective, on a large interobserver scale. To satisfy ROSE’s needs, a rapid, automated, and accurate diagnosis system using EBUS-TBNA whole-slide images (WSIs) is highly desired to improve diagnosis accuracy and speed, minimize workload and labor costs, and ensure reproducibility. We present a fast, efficient, and fully automatic deep-convolutional-neural-network-based system for advanced lung cancer staging on gigapixel EBUS-TBNA cytological WSIs. Each WSI was converted into a patch-based hierarchical structure and examined by the proposed deep convolutional neural network, generating the segmentation of metastatic lesions in EBUS-TBNA WSIs. To the best of the authors’ knowledge, this is the first research on fully automated enlarged mediastinal lymph node analysis using EBUS-TBNA cytological WSIs. We evaluated the robustness of the proposed framework on a dataset of 122 WSIs, and the proposed method achieved a high precision of 93.4%, sensitivity of 89.8%, DSC of 82.2%, and IoU of 83.2% for the first experiment (37.7% training and 62.3% testing) and a high precision of 91.8 ± 1.2, sensitivity of 96.3 ± 0.8, DSC of 94.0 ± 1.0, and IoU of 88.7 ± 1.8 for the second experiment using a three-fold cross-validation, respectively. Furthermore, the proposed method significantly outperformed the three state-of-the-art baseline models, including U-Net, SegNet, and FCN, in terms of precision, sensitivity, DSC, and Jaccard index, based on Fisher’s least significant difference (LSD) test (p<0.001). For a computational time comparison on a WSI, the proposed method was 2.5 times faster than U-Net, 2.3 times faster than SegNet, and 3.4 times faster than FCN, using a single GeForce GTX 1080 Ti, respectively. With its high precision and sensitivity, the proposed method demonstrated that it manifested the potential to reduce the workload of pathologists in their routine clinical practice.

Neuroendocrine Tumor Diagnosed Through Endoscopic Ultrasound-Guided Fine-Needle Biopsy of a Lung Mass

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is an excellent modality for tissue acquisition and has been shown to be superior to EUS-fine-needle aspiration in several studies. Although tissue sampling of lung nodules using EUS-fine-needle aspiration has been reported in the literature, the use of EUS-FNB for tissue acquisition of parenchymal lung mass has rarely been reported in the literature. Our report highlights that EUS-FNB is safe and effective for lung lesions that are near the esophageal wall.

Useful on-site macroscopic quantitative evaluation of EBUS-TBNA samples

Background

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive diagnostic test with a high diagnostic yield. Optimal specimen acquisition is of a key importance; however, rapid on-site cytology examination (ROSE) during EBUS-TBNA has limited access. In an attempt to provide immediate feedback to the operator, the intervention pulmonology team started to classify macroscopically every lymph node sample in terms of abundance. The main objective of this study was to clarify whether this on-site macroscopic evaluation of EBUS sample was related to histology results and therefore any helpful for clinical practice.

Results

From a total of 288 lymph node stations sampled, adequate/diagnostic histological results were present in 11.1% of “insufficient” samples, 40.9% “sufficient” samples, 76.4% “good” samples and 88.1% of “excellent” samples. This was statistically significant with p-value under 0.0001. Also, there was a statistical agreement between samples that were macroscopically “insufficient” or “sufficient” with “inadequate” and “dubious” histological results and also between macroscopically “good” and “excellent” samples and histological results that were adequate/diagnostic. And that statistical agreement was of moderate magnitude according to the “Landis and Koch” classification (k = 0.386).

Conclusions

The positive relationship between the on-site macroscopic evaluation of the EBUS sample as “excellent” and the “adequate/diagnostic” histological result is of high clinical importance since it represents a fast, cheap and easy method that provides immediate feedback to the operator influencing his conduct; by obtaining additional passes to achieve an “excellent” will ensure a higher percentage of samples with a diagnosis, accelerating the patients treatment.

Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA): Technical Updates and Pathological Yield

Since the endobronchial ultrasound bronchoscope was introduced to clinical practice, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become the procedure of choice to sample hilar and mediastinal adenopathy. Multiple studies have been conducted in the last two decades to look at the different technical aspects of the procedure and their effects on the final cytopathological yield. In addition, newer modes of ultrasound scanning and newer tools with the potential to optimize the selection and sampling of the target lymph node have been introduced. These have the potential to reduce the number of passes, reduce the procedure time, and increase the diagnostic yield, especially in rare tumors and benign diseases. Herein, we review the latest updates related to the technical aspects of EBUS-TBNA and their effects on the final cytopathological yield in malignant and benign diseases.

Small-Cell Carcinoma of the Lung: What We Learned about It?

Small-cell lung carcinoma (SCLC) is a high-grade aggressive disease that belongs to the neuroendocrine (NE) group of lung tumors that also includes typical carcinoid, atypical carcinoid, and large-cell NE carcinoma. SCLC has specific histological diagnostic criteria that are sometimes troublesome to be assessed in cytological samples that indeed represent the most frequent source of diagnostic material due to the typical advanced presentation at the onset of SCLC. However, cytological preparations could be in some instances more reliable than histology due to the better preservation of nuclear details. Cytological criteria for diagnosis of SCLC include high cellularity, small cell size, scant cytoplasm, coarsely granulated chromatin with "salt-and-pepper" appearance, inconspicuous or absent nucleoli, Azzopardi crush effect, and necrotic debris in the background. Despite being distinctive, these features could be incomplete to differentiate SCLC with other small-cell neoplasia. Therefore, immunocytochemical determination of diagnostic biomarkers is crucial to achieve a confident diagnosis. Furthermore, recent findings on molecular and transcriptomic studies of SCLC revealed the potential rise of new predictive and prognostic biomarkers that, whenever validated by immunocytochemistry, may potentially assist to tailor the best therapy, including immune checkpoint inhibition.

The changes on anesthetic practice for non-intubated bronchoscopic interventions during Covid-19 pandemic

Bronchoscopic interventions (BIs) and airway management for bronchoscopy are exceptionally high-risk procedures not only for anesthesiologists, pulmonologists, but also for nursing staff because they expose nurses to COVID-19-containing droplets. However, perioperative changes can be made to the anesthetic management for nonintubated BIs to minimize the spread of COVID-19.

EBUS-TBNA Cytological Samples for Comprehensive Molecular Testing in Non-Small Cell Lung Cancer

Clinical guidelines promote the identification of several targetable biomarkers to drive treatment decisions in advanced non-small cell lung cancer (NSCLC), but half of all patients do not have a viable biopsy. Specimens from endobronchial-ultrasound transbronchial needle aspiration (EBUS-TBNA) are an alternative source of material for the initial diagnosis of NSCLC, however their usefulness for a complete molecular characterization remains controversial. EBUS-TBNA samples were prospectively tested for several biomarkers by next-generation sequencing (NGS), nCounter, and immunohistochemistry (PD-L1). The primary objectives were to assess the sensitivity of EBUS-TBNA samples for a comprehensive molecular characterization and to compare its performance to the reference standard of biopsy samples. Seventy-two EBUS-TBNA procedures were performed, and 42 NSCLC patients were diagnosed. Among all cytological samples, 92.9% were successfully genotyped by NGS, 95.2% by nCounter, and 100% by immunohistochemistry. There were 29 paired biopsy samples; 79.3% samples had enough tumor material for genomic genotyping, and 96.6% for PD-L1 immunohistochemistry. A good concordance was found between both sources of material: 88.9% for PD-L1, 100% for NGS and nCounter. EBUS-TBNA is a feasible alternative source of material for NSCLC genotyping and allows the identification of patient candidates for personalized therapies with high concordance when compared with biopsy.

Molecular and Genomic Profiling of Lung Cancer in the Era of Precision Medicine: A Position Paper from the Italian Association of Thoracic Oncology (AIOT)

The identification of the optimal cancer treatment has become progressively more intricate for non-small-cell lung cancer (NSCLC) patients due to the multitude of options available. The testing of biomarkers to predict clinical responses to therapies is pivotal to stratify the patients based on the molecular features of their tumors. The number of actionable genetic alterations to be tested is increasing together with the comprehension of the molecular mechanisms underlying tumor growth and development. The possibility of using next generation sequencing-based approaches enhanced the acquisition of genetic data with potential clinical usefulness, and favored the integration of precision medicine in clinical practice. The availability of targeted sequencing panels that cover genetic alterations in hundreds of genes allows the performance of a comprehensive genomic profiling (CGP) of lung tumors. However, different issues still need to be solved, from the tissue needed for next generation sequencing analysis, to the choice of the test and its interpretation in the clinical context. This position paper from the Italian Association of Thoracic Oncology (AIOT) summarizes the results of a discussion from a Precision Medicine Panel meeting on the challenges to bringing CGP and, therefore, precision medicine into the daily clinical practice.

The utility of immunohistochemical testing for mismatch repair proteins in fine needle aspiration specimens of pancreatic adenocarcinoma

INTRODUCTION

Microsatellite instability (MSI) testing is recommended for all colonic and endometrial carcinomas to screen for Lynch syndrome. The role of MSI testing in pancreatic adenocarcinoma has not been well-established. Screening can be done via immunohistochemical (IHC) staining for mismatch repair (MMR) proteins (MLH1, MSH2, MSH6, PMS2). We report our experience and the clinical utility of MMR IHC on pancreatic adenocarcinomas in fine-needle aspiration (FNA) specimens.

MATERIALS AND METHODS

We performed a retrospective review to identify all patients diagnosed with pancreatic adenocarcinoma by FNA at our institution between December 2017 and September 2019. For cases with sufficient tumor cells for testing, the MMR results and morphology were summarized, as well as corresponding clinical information, including age, clinical stage, treatment, and concurrent other cancers.

RESULTS

From December 2017 to September 2019, there were a total of 184 pancreatic FNAs with a diagnosis of adenocarcinoma. Of these 184 FNAs, 65 (35%) contained sufficient material in the cell block to perform IHC for MMR. The cell block material was collected in either RPMI or CytoLyt. Poor technical quality precluded interpretation of PMS2 in 4 cases and MSH6 in 2 cases. All other cases showed intact expression of all four proteins.

CONCLUSIONS

IHC for MMR proteins can be done on specimens collected in RPMI or CytoLyt, but RPMI appears to be more reliable. None of the pancreatic adenocarcinomas in this study showed loss of MMR protein expression. Routine testing of MMR loss may not be indicated in pancreatic adenocarcinomas in the general patient population.

Processing and Reporting of Cytology Specimens from Mediastinal Lymph Nodes Collected using Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: A State-of-the-Art Review

Endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) is presently the preferred modality for sampling mediastinal lymph nodes. There is an unmet need for standardization of processing and reporting of cytology specimens obtained by EBUS-TBNA. The manuscript is a state-of-the-art review on the technical aspects of processing and reporting of EBUS-TBNA specimens. A literature search was conducted using the PubMed database, and the available evidence was discussed among the authors. The evidence suggests that at least one air-dried and one alcohol-fixed slide should be prepared from each lymph node pass. The remaining material should be utilized for microbiological analysis (in saline) and cell block preparation (10% formalin or other solutions). Wherever available, rapid-onsite evaluation should be performed to assess the adequacy of the sample and guide the need for additional material. The lymph node aspirate should also be collected in Roswell Park Memorial Institute solution in cases where lymphoma is under consideration. The use of liquid-based cytology provides good quality specimens that are free from blood and air-drying artifacts and can be used wherever available. Sample adequacy and the diagnostic category should be furnished separately in the cytology report.

Endobronchial ultrasound-guided intranodal forceps biopsy (EBUS-IFB)-technical review

Endobronchial ultrasound (EBUS) and transbronchial needle aspiration (TBNA) have changed the landscape of pulmonology. Mediastinal structures beyond the confines of airway walls are visualized in real-time with EBUS, leading to improved accuracy of tissue sampling and diagnostic yield. With the development of various needle sizes ranging from 25-G to 19-G, the sampling of lymph nodes is becoming easier and more commonplace. Yet, certain conditions such as sarcoidosis and lymphoma may still be difficult to diagnose via EBUS-TBNA. Furthermore, in the age of targeted therapy, there are more demands on EBUS-TBNA samples for molecular marker testing and next-generation sequencing. Here, we present a complementary methodology, EBUS-guided intranodal forceps biopsy (EBUS-IFB), for tissue acquisition that may help address these deficiencies. Specifically, we aim to propose indications, contraindications, outline approaches in performing IFB, and provide an overview of the data for this complementary technique.

Precision cytopathology: expanding opportunities for biomarker testing in cytopathology

Precision cytopathology refers to therapeutically linked biomarker testing in cytopatology, a dynamically growing area of the discipline. This review describes basic steps to expand precision cytopathology services. Focusing exclusively on solid tumors, the review is divided into four sections: Section 1: Overview of precision pathology- opportunities and challenges; Section 2: Basic steps in establishing or expanding a precision cytopathology laboratory; Section 3: Cytopathology specimens suitable for next generation sequencing platforms; and Section 4: Summary. precision cytopathology continues to rapidly evolve in parallel with expanding targeted therapy options. Biomarker assays (companion diagnostics) comprise a multitude of test types including immunohistochemistry, in situ hybridization and molecular genetic tests such as PCR and next generation sequencing all of which are performable on cytology specimens. Best practices for precision cytopathology will incorporate traditional diagnostic approaches allied with careful specimen triage to enable successful biomarker analysis. Beyond triaging, cytopathologists knowledgeable about molecular test options and capabilities have the opportunity to refine diagnoses, prognoses and predictive information thereby assuming a lead role in precision oncology biomarker testing.

Endobronchial ultrasound-guided fine-needle aspiration for pulmonary carcinomas genotyping: experience with 398 cases including rapid EGFR/KRAS analysis in 43 cases

BACKGROUND

Endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA) of mediastinal lymph nodes is a minimally invasive and efficient tool for both diagnosis and staging of lung cancer. EBUS-FNA also permits tumor genotyping. However this critical datum for the therapeutic management is often long to obtain for metastatic patients with short life expectancy.

METHODS

From May 2011 to December 2017, 398 lung cancer patients underwent a genetic analysis based on EBUS-FNA samples. EBUS-FNAs were performed with rapid on-site evaluation. Mutations were studied with Sanger or new generation sequencing. Forty-three cases were also tested with a fully automated real-time PCR rapid technique. ALK abnormalities were assessed by immunohistochemistry and/or in situ hybridization.

RESULTS

A genotypic result could be obtained in 316 cases (79.4%) and in 180 of the 198 more recent cases (90.9%). Genetic abnormalities were observed in 191 cases (48.0%). Using the rapid technique, EGFR/KRAS mutational status was obtained within a few hours following the histological diagnosis and on the same day of the EBUS-FNA by analyzing fresh specimens after intra-operative cytological diagnosis.

CONCLUSIONS

In term of molecular diagnosis, EBUS-FNA provides high-quality biological material similar to that of other clinical sampling methods. Furthermore, our study suggests that a rapid molecular diagnostic method could lead to a prompt and appropriate therapeutic management for many advanced stage patients.

Endobronchial Ultrasound-guided Transbronchial Needle Aspiration With a 19-G Needle Device

BACKGROUND

Endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration is a well-established first-line minimally invasive modality for mediastinal lymph node sampling. Although results are excellent overall, the technique underperforms in certain situations. We aimed to describe our results using a new 19-G EBUS-guided transbronchial needle aspiration device to determine safety and feasibility of this approach.

METHODS

We completed a retrospective chart review of all cases performed to the time of data analysis at each of 3 study sites.

RESULTS

A total of 165 procedures were performed with a total of 297 individual lymph nodes or lesions sampled with the 19-G device by 10 bronchoscopists. Relatively large targets were selected for sampling with the device (mean lymph node size: 20.4 mm; lung lesions: 33.5 mm). A specific diagnosis was obtained in 77.3% of cases with an additional 13.6% of cases with benign lymphocytes, for a procedural adequacy rate of 90.9%. Procedure sample adequacy was 88.6% in suspected malignant cases, 91.0% in suspected sarcoidosis/lymphadenopathy cases, and 85.7% of cases with suspected lymphoma. On a per-node basis, a specific diagnosis was noted in 191/280 (68.2%) of samples, with an additional 61 showing benign lymphocytes for a per-node sample adequacy rate of 90%. One case (0.6%) of intraprocedure bleeding was noted.

CONCLUSIONS

A new flexible 19-G EBUS needle was successfully and safely applied in a large patient cohort for sampling of lung and enlarged mediastinal lesions with high diagnostic rates across clinical indications.

The diagnostic value of tissue button technique for specimen accusation during endobronchial ultrasound-guided transbronchial fine-needle aspiration

INTRODUCTION

The quality of tissue acquisition during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a major determinant of the diagnostic yield of the procedure. In the tissue button (TB) technique, the retrieved cellular specimen is fixed in ethanol and subsequently scraped from slide using surgical blade into formaldehyde and processed like ordinary tissue biopsy thus potentially increasing its diagnostic value.

OBJECTIVES

To retrospectively evaluate the diagnostic yield of a TB technique in patients undergoing EBUS-TBNA for various malignant and benign conditions.

METHODS

The diagnostic yield of specimen obtained by two methods (TB and traditional cell-block technique) performed during the same procedure are outlined in 46 patients who underwent EBUS-TBNA (median age = 65, range 19-85 years).

RESULTS

Overall, in both malignant and benign conditions, TB resulted in clear diagnostic material in 43/46 (93.4%) patients. Specifically, TB provided clear histological diagnosis of malignancy (either primary lung cancer or metastases from extra-thoracic cancer) in 30/46 (65.2%) patients and granulomatous inflammation in 11/46 (23.9%) of patients. Only in two patients TB did not provide diagnostic material.

CONCLUSIONS

The newly introduced TB technique provides valuable histological diagnostic material during EBUS-TBNA both malignant and benign conditions. Given its simplicity and its high diagnostic yield, TB should be considered to be used as one of the preferred specimen acquisition modalities during EBUS-TBNA specimen processing. Direct comparison to alternative tissue processing techniques during EBUS-TBNA should be explored in further randomized prospective studies.