Utility of bronchoscopically obtained frozen cytology pellets for next-generation sequencing.

BACKGROUND: Next-generation sequencing (NGS) is essential for lung cancer treatment. It is important to collect sufficient tissue specimens, but sometimes we cannot obtain large enough samples for NGS analysis. We investigated the yield of NGS analysis by frozen cytology pellets using an Oncomine Comprehensive Assay or Oncomine Precision Assay. METHODS: We retrospectively enrolled patients with lung cancer who underwent bronchoscopy at Kobe University Hospital and were enrolled in the Lung Cancer Genomic Screening Project for Individualized Medicine. We investigated the amount of extracted DNA and RNA and determined the NGS success rates. We also compared the amount of DNA and RNA by bronchoscopy methods. To create the frozen cytology pellets, we first effectively collected the cells and then quickly centrifuged and cryopreserved them. RESULTS: A total of 132 patients were enrolled in this study between May 2016 and December 2022; of them, 75 were subjected to frozen cytology pellet examinations and 57 were subjected to frozen tissue examinations. The amount of DNA and RNA obtained by frozen cytology pellets was nearly equivalent to frozen tissues. Frozen cytology pellets collected by endobronchial ultrasound-guided transbronchial needle aspiration yielded significantly more DNA than those collected by transbronchial biopsy methods. (P < 0.01) In RNA content, cytology pellets were not inferior to frozen tissue. The success rate of NGS analysis with frozen cytology pellet specimens was comparable to the success rate of NGS analysis with frozen tissue specimens. CONCLUSIONS: Our study showed that frozen cytology pellets may have equivalent diagnostic value to frozen tissue for NGS analyses. Bronchial cytology specimens are usually used only for cytology, but NGS analysis is possible if enough cells are collected to create pellet specimens. In particular, the frozen cytology pellets obtained by endobronchial ultrasound-guided transbronchial needle aspiration yielded sufficient amounts of DNA. TRIAL REGISTRATION: This was registered with the University Medical Hospital Information Network in Japan (UMINCTR registration no. UMIN000052050).

EBUS-TBNA for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer clinically staged with PET/CT.

BACKGROUND AND OBJECTIVE: To evaluate the diagnostic accuracy and clinical usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer (NSCLC) clinically staged with positron emission tomography/computed tomography (PET/CT). METHODS: We conducted a study that included patients with centrally located T1N0M0 NSCLC, clinically staged with PET/CT who underwent EBUS-TBNA for mediastinal staging. Patients with negative EBUS-TBNA underwent mediastinoscopy, video-assisted mediastinoscopic lymphadenectomy (VAMLA) and/or lung resection with systematic nodal dissection, that were considered the gold standard. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), overall accuracy of EBUS-TBNA for diagnosing mediastinal metastases (N2 disease) and the number needed to treat (NNT: number of patients needed to undergo EBUS-TBNA to avoid a case of pathologic N2 disease after resection) were calculated. RESULTS: One-hundred eighteen patients were included. EBUS-TBNA proved N2 disease in four patients. In the remaining 114 patients who underwent mediastinoscopy, VAMLA and/or resection there were two cases of N2 (N2 prevalence 5.1%). The sensitivity, specificity, NPV, PPV and overall accuracy for diagnosing mediastinal metastases (N2 disease) were of 66%, 100%, 98%, 100% and 98%, respectively. The NNT was 31 (95% CI: 15-119). CONCLUSION: EBUS-TBNA in patients with central clinically staged T1N0M0 NSCLC presents a good diagnostic accuracy for mediastinal staging, even in a population with low prevalence of N2 disease. Therefore, its indication should be considered in the management of even these early lung cancers.

Comparison of the specimen quality of endobronchial ultrasound-guided intranodal forceps biopsy using standard-sized forceps versus mini forceps for lung cancer: A prospective study.

BACKGROUND AND OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a diagnostic procedure with adequate performance; however, its ability to provide specimens of sufficient quality and quantity for treatment decision-making in advanced-stage lung cancer may be limited, primarily due to blood contamination. The use of a 0.96-mm miniforceps biopsy (MFB) permits true histological sampling, but the resulting small specimens are unsuitable for the intended applications. Therefore, we introduced a 1.9-mm standard-sized forceps biopsy (SFB) and compared its utility to that of MFB. METHODS: We prospectively enrolled patients from three institutions who presented with hilar/mediastinal lymphadenopathy and suspected advanced-stage lung cancer, or those who were already diagnosed but required additional tissue specimens for biomarker analysis. Each patient underwent MFB followed by SFB three or four times through the tract created by TBNA using a 22-gauge needle on the same lymph node (LN). Two pathologists assessed the quality and size of each specimen using a virtual slide system, and diagnostic performance was compared between the MFB and SFB groups. RESULTS: Among the 60 enrolled patients, 70.0% were diagnosed with adenocarcinoma. The most frequently targeted sites were the lower paratracheal LNs, followed by the interlobar LNs. The diagnostic yields of TBNA, MFB and SFB were 91.7%, 93.3% and 96.7%, respectively. The sampling rate of high-quality specimens was significantly higher in the SFB group. Moreover, the mean specimen size for SFB was three times larger than for MFB. CONCLUSION: SFB is useful for obtaining sufficient qualitative and quantitative specimens.

Endobronchial Ultrasound Guided Transbronchial Needle Aspiration and PD-L1 Yields.

PURPOSE: Immunotherapy is a leading approach for treating advanced non-small cell lung cancer (NSCLC) by targeting the PD-1/PD-L1 checkpoint signaling pathway, particularly in tumors expressing high levels of PD-L1 (Jug et al. in J Am Soc Cytopathol 9:485-493, 2020; Perrotta et al. in Chest 158: 1230-1239, 2020). Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive method to obtain tissue for molecular studies, including PD-L1 analysis, in unresectable tumors (Genova et al. in Front Immunol 12: 799455, 2021; Wang et al. in Ann Oncol 29: 1417-1422, 2018). This study aimed to assess the adequacy of PD-L1 assessment in EBUS-TBNA cytology specimens. METHODS: Data was collected retrospectively from patients who underwent EBUS-TBNA between 2017 and 2021 for suspected lung cancer biopsy. Samples positive for NSCLC were examined for PD-L1 expression. EBUS was performed by experienced practitioners, following institutional guidelines of a minimum of five aspirations from positively identified lesions. Sample adequacy for molecular testing was determined by the pathology department. RESULTS: The analysis involved 387 NSCLC cases (149 squamous cell, 191 adenocarcinoma, 47 unspecified). Of the 263 EBUS-TBNA specimens tested for PD-L1, 237 (90.1%) were deemed adequate. While 84% adhered to the protocol, adherence did not yield better results. Significantly higher PD-L1 adequacy was observed in squamous cell carcinomas (93.2%) compared to adenocarcinoma (87.6%). The number of aspirations and sedation type did not correlate with PD-L1 adequacy in either cancer type, but lesion size and location had a significant impact in adenocarcinomas. Adenocarcinoma exhibited higher PD-L1 expression (68%) compared to squamous cell carcinoma (48%). CONCLUSION: EBUS-TBNA offers high yields for assessing immunotherapy markers like PD-L1, with satisfactory adequacy regardless of NSCLC subtype, lesion size, or location.

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.

Whole Genome Sequencing in Advanced Lung Cancer can be Performed Using Diff-Quik Cytology Smears Derived from Endobronchial Ultrasound, Transbronchial Needle Aspiration (EBUS TBNA).

INTRODUCTION: Maximising alternative sample types for genomics in advanced lung cancer is important because bronchoscopic samples may sometimes be insufficient for this purpose. Further, the clinical applications of comprehensive molecular analysis such as whole genome sequencing (WGS) are rapidly developing. Diff-Quik cytology smears from EBUS TBNA is an alternative source of DNA, but its feasibility for WGS has not been previously demonstrated. METHODS: Diff-Quik smears were collected along with research cell pellets. RESULTS: Tumour content of smears were compared to research cell pellets from 42 patients, which showed good correlation (Spearman correlation 0.85, P < 0.0001). A subset of eight smears underwent WGS, which presented similar mutation profiles to WGS of the matched cell pellet. DNA yield was predicted using a regression equation of the smears cytology features, which correctly predicted DNA yield > 1500 ng in 7 out of 8 smears. CONCLUSIONS: WGS of commonly collected Diff-Quik slides is feasible and their DNA yield can be predicted.

Clinical application of endobronchial ultrasonography-guided transbronchial needle aspiration biopsy-a single center, large sample, real-world study.

BACKGROUND: Endobronchial ultrasonography-guided transbronchial needle aspiration biopsy (EBUS-TBNA) has been used for more than 10 years in China. Its clinical application and diagnostic value in different diseases with large sample was lack of report. METHODS: A retrospective analysis was performed about the application and diagnostic value of EBUS-TBNA in different disease of patients in Respiratory Intervention Center of Guangzhou Institute of Respiratory Health from January 2012 to July 2020. RESULTS: A total 5758 patients were included with 182 patients excluded for lack of information. Finally, data of 5576 patients (3798 males and 1778 females) were analyzed. For anesthetize, most patients were undergoing general anesthesia of intravenous with spontaneous breathing (69.4%), followed by general anesthesia of intravenous and inhalation with tracheal intubation and mechanical ventilation (17.9%) and conscious sedation and analgesia (12.8%). Lymph nodes were the main sites of biopsy obtained (76.4%). Tumors accounted for the highest proportion of disease (66.4%), followed by infection diseases (9.9%), sarcoidosis (3.9%), lymphoma (1.1%), and others (18.7%). The sensitivity of EBUS-TBNA for diagnosis of tumor was 89.7%, and 40.8% for infection diseases. There were significant differences in the puncture site and proportions of diseases between male and females (both p < 0.05). Higher diagnostic value was found in male patients (p < 0.05). CONCLUSION: EBUS-TBNA has good diagnostic value for different mediastinal and central pulmonary space-occupying lesions diseases, with highest sensitivity for tumors. Higher diagnostic value was found in male patients.

The utility of WhatsApp-based off-site evaluation for rapid cytology of EBUS-TBNA samples.

BACKGROUND: Whether off-site evaluation of slides by a cytologist viewing the images shared by WhatsApp improves the on-site evaluation by a pulmonologist (P-ROSE) remains unknown. This study's objective was to compare the sensitivity of P-ROSE and WHOSE for adequacy and diagnosis of cytology specimens obtained by endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA). MATERIALS AND METHODS: We retrospectively reviewed our bronchoscopy database to identify subjects who underwent EBUS-TBNA for lymph node sampling and had reports of P-ROSE and WHOSE. We collected data on the adequacy of samples as reported by the pulmonologist (P-ROSE), remotely by the cytologist (WHOSE), and finally after detailed cytologic evaluation. The study's primary outcome was to assess the increment in sensitivity for adequacy and diagnostic category (using the final cytology report as reference) by incorporating WHOSE. RESULTS: We included 264 (P-ROSE, n = 184; WHOSE, n = 80) subjects. The sensitivity (95% CI) for sample adequacy by P-ROSE and WHOSE was 65.3% (57.9%-72%) and 92% (83.6%-96.2%), respectively. There was a 26.6% (95% CI, 16%-35.2%) increment in the sensitivity for adequacy. The sensitivity (95% CI) for diagnosis by P-ROSE and WHOSE was 53.9% (46%-61.1%) and 89.8% (79.5%-95.3%), respectively. There was a 35.9% (95% CI, 23.4%-45%) increment in the sensitivity for diagnosis with WHOSE. The agreement between P-ROSE and final cytology in adequacy was poor (κ = -0.023, p = 0.616). The agreement between WHOSE and final cytology was moderate for adequacy (κ = 0.491, p = <0.001). CONCLUSION: We found WHOSE significantly improves the performance of P-ROSE for rapid assessment of cytology specimens obtained by EBUS-TBNA.

A Case of Mediastinal Tuberculous Lymphadenitis in a Chronic Dialysis Patient Diagnosed by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA).

A 54-year-old woman on dialysis due to chronic renal failure had a fever lasting 2 weeks and was referred to a hospital. Non-enhanced CT and blood tests showed no remarkable findings. She was hospitalized and received an antibacterial drug. Although she was discharged after the fever subsided, she was hospitalized again due to a fever a few days later. A contrast-enhanced CT revealed mediastinal lymphadenopathy, and she was transferred to our hospital for a bronchoscopy. Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) for subcarinal lymph nodes was performed in our hospital. The Polymerase Chain Reaction (PCR) test of the obtained specimen was positive for mycobacterium tuberculosis, and histologically, caseous granulomas were found in the specimen. She was diagnosed with mediastinal tuberculous lymphadenitis, and HREZ (isoniazid, rifampicin, ethambutol, and pyrazinamide) treatment was started. The fever subsided immediately, and she was discharged from our hospital 2 weeks after the initiation of treatment. Thereafter, she received treatment as an outpatient. Since the use of a contrast medium was complicated by dialysis, a non-enhanced CT was performed at first, and it was difficult to make a diagnosis from this. We report this as an informative case that could be diagnosed with EBUS-TBNA, which was easily performed on a patient weakened by prolonged fever and dialysis.

Effect of chlorhexidine Mouthrinse on prevention of microbial contamination during EBUS-TBNA: a randomized controlled trial.

BACKGROUND: Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure, fatal infectious complications have been reported. However, adequate preventive strategies have not been determined. We aimed to investigate the effect of chlorhexidine mouthrinse on the prevention of microbial contamination during EBUS-TBNA. METHODS: In this single-center, assessor-blinded, parallel-group randomized controlled trial, we randomly assigned adult participants undergoing EBUS-TBNA using a convex probe to gargle for 1 minute with 100 mL of 0.12% chlorhexidine gluconate before EBUS-TBNA or to receive usual care (no chlorhexidine mouthrinse). Aspiration needle wash samples were collected immediately after completion of EBUS-TBNA by instilling sterile saline into the used needle. The primary outcome was colony forming unit (CFU) counts per mL of needle wash samples in aerobic cultures. Secondary outcomes were CFU counts per mL of needle wash samples in anaerobic cultures, fever within 24 hours after EBUS-TBNA, and infectious complications within 4 weeks after EBUS-TBNA. RESULTS: From January 2021 to June 2021, 106 patients received either chlorhexidine mouthrinse (n = 51) or usual care (n = 55). The median CFU counts of needle wash samples in aerobic cultures were not significantly different in the two groups (10 CFU/mL vs 20 CFU/mL; P = 0.70). There were no significant differences between the groups regarding secondary outcomes, including median CFU counts in anaerobic cultures (P = 0.41) and fever within 24 hours after EBUS-TBNA (11.8% vs 5.6%, P = 0.31). There were no infectious complications within 4 weeks in both groups. CONCLUSIONS: Chlorhexidine mouthrinse did not reduce CFU counts in needle wash samples of EBUS-TBNA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04718922 . Registered on 22/01/2021.

Comparison of a 22G Crown-Cut Needle with a Conventional 22G Needle with EBUS Guidance in Diagnosis of Sarcoidosis.

INTRODUCTION: Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is a standard procedure in cases of enlarged mediastinal lymph nodes. Recently, new tools were developed aiming to improve the diagnostic yield. A novel crown-cut needle is considered to obtain tissue cores which can be beneficial for the evaluation by the pathologist. This study aimed to compare the novel 22G crown-cut needle with a conventional 22G needle with EBUS guidance in the diagnosis of sarcoidosis. METHODS: We designed a single-center prospective randomized clinical trial between March 2020 and January 2021 with 30 patients with mediastinal lymphadenopathy and suspected sarcoidosis. RESULTS: 24 patients (mean age 49.5 vs 54.1, mean FVC 73.7% vs 86.7%, mean DLCO 72.4% vs 72.5% for crown-cut needle vs conventional needle, respectively) were diagnosed with sarcoidosis. In the remaining six patients, sarcoidosis was reasonably excluded. The diagnostic yield for sarcoidosis was 77% with the crown-cut needle vs. 82% with the conventional needle (p > 0.05). In patients with histopathologic hallmarks typical of sarcoidosis (n = 19), the crown-cut needle was superior in detecting granulomas (8.3 vs 3.8 per cytoblock, p < 0.05) and histiocytes (502 vs 186 per cytoblock, p < 0.05). Four of seven bronchoscopists experienced difficulties passing through the bronchial wall with the crown-cut needle and one episode of bleeding occurred in this group which made interventions necessary. CONCLUSIONS: Despite equivalence in diagnostic accuracy, the crown-cut needle was superior to the conventional needle in detecting granulomas and histiocytes. This indicates greater potential for obtaining higher quality sample material with the crown-cut needle in cases of granulomatous inflammation.

Optimizing the endoscopic diagnosis of mediastinal lymphadenopathy: a glimpse on cryobiopsy.

Etiological diagnosis of mediastinal lymphadenopathy represents a daily challenge. Endosonography (transesophageal and transbronchial ultrasound-guided needle aspiration) is the recommended technique in the first diagnostic work-up and in the mediastinal staging of lung cancer. Despite a good sensitivity, limited amount of collected tissue may hamper molecular assessment in advanced lung cancer and in the diagnosis of lymphoproliferative disorders, fibrotic sarcoidosis, and mycobacterial lymphadenitis. Cryobiopsy, a bronchoscopic technique based on cooling, crystallization, and subsequent collection of tissue, has been successfully employed in the diagnosis of interstitial lung diseases. Cryoprobes provide larger amount of tissue than conventional bronchoscopic sampling tools and might potentially prevent the need for invasive surgical procedures. New applications of the technique (e.g., bronchoscopic diagnosis of peripheral pulmonary lesions and mediastinal lymph nodes) have been recently described in few reports. In a recent issue of the Journal, Genova et al. described five patients who underwent endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) followed by ultrasound-guided transbronchial cryobiopsy of mediastinal lymphadenopathy for a suspected malignancy. The authors discussed about the potential added value of mediastinal cryobiopsy on a correct histopathological and molecular assessment in patients with malignancies. EBUS-cryobiopsy could be a promising technique in the diagnostic pathway of mediastinal lymphadenitis. However, cryobiopsy is now available only in few selected centres. The learning curve of the technique adapted to mediastinal ultrasound-guided sampling, the optimal sampling strategy, its true diagnostic accuracy in patients with malignant and benign diseases, as well as its safety, are still largely unclear. Mediastinal cryobiopsy could be complementary rather than alternative to conventional endosonography. Rapid on-site evaluation of EBUS-TBNA could guide subsequent sampling with cryoprobes in case of poor collection of biological material or in case of suspected lymphoproliferative disorders. Further studies should investigate its diagnostic yield, in comparison or in combination with conventional endosonography, in large cohorts of patients with malignant or benign mediastinal lymphadenopthies.

Endobronchial ultrasound-guided transbronchial needle aspiration in patients with previously treated malignancies: diagnostic performance and predictive value.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration is a minimally invasive and effective sampling approach for patients with mediastinal or hilar lymphadenopathy. Increased recognition of the ultrasonographic features revealed the value of its images in predicting mediastinal lymph node malignancy. However, its diagnostic validity and the predictive value of its ultrasonographic features have not been demonstrated well in patients after systemic anti-tumor therapy. This study aimed to evaluate the efficiency of endobronchial ultrasound-guided transbronchial needle aspiration in patients with suspicious lymph nodes after anti-tumor therapy. METHODS: We retrospectively reviewed cases of endobronchial ultrasound-guided transbronchial needle aspiration performed between January 2019 and August 2021 at a single tertiary hospital center. Patients with suspected mediastinal or hilar lymph nodes within 5 years of systemic anti-tumor therapy were enrolled. Final diagnoses were determined by pathologic diagnoses of samples from transbronchial needle aspiration, surgery, or follow-up for at least 6 months. Ultrasonographic features were analyzed to assess the predictive value of malignant lymph nodes after treatment. RESULTS: Overall, 168 lymph nodes of 138 patients were analyzed. Among 110 (65.5%) malignant lymph nodes, 75 originated from lung cancers; the other 35 were from other malignancies. No complications related to endobronchial ultrasound-guided transbronchial needle aspiration were observed. Of 58 negative results of transbronchial needle aspiration, 51 were proven to be true negatives; 7 were false. The overall sensitivity and the negative predictive value were 94.02% and 87.93%, respectively. Univariate and multivariate analysis revealed the absence of central hilar structure and short axis > 10 mm as independent predictive factors for malignancy. CONCLUSIONS: Endobronchial ultrasound-guided transbronchial needle aspiration performs satisfactorily in diagnosing mediastinal and hilar lymphadenopathy even after anti-tumor treatment.

Potential application of cryobiopsy for histo-molecular characterization of mediastinal lymph nodes in patients with thoracic malignancies: a case presentation series and implications for future developments.

BACKGROUND: The management of non-small cell lung cancer (NSCLC) has become increasingly complex due to the evolution of personalized medicine approaches. Such approaches are characterized by the necessity of adequate tumor samples; hence, improved biopsy techniques are needed. Transbronchial lung cryobiopsy is a novel endoscopic procedure designed to collect peripheral pulmonary tissue, and it is currently employed in interstitial lung diseases. The use of this technique in oncology might result in improved mediastinum staging and molecular characterizations; however, available data involving the use of a cryoprobe on mediastinal lymph nodes are still limited. CASE PRESENTATION: Here we present a series of five consecutive patients who underwent endoscopic assessment of mediastinal lymph nodes for oncologic reasons. All patients were subjected both to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS TBNA) and cryobiopsy of mediastinal lymph nodes during the same procedure, and no complications were observed. In three of the reported cases, both cryobiopsy and cell block from EBUS TBNA were positive, while in one case cryobiopsy was not diagnostic and EBUS TBNA was negative; moreover, one case showed discordance between the procedures, as cryobiopsy was negative and cell block obtained from multiple stations was diagnostic for small cell lung cancer. In one case involving a patient treated for lymphoma, cryobiopsy provided more complete histologic characterization, and in another case involving a patient affected by NSCLC cryobiopsy provided more material for molecular analyses. CONCLUSION: This case presentation series suggests that cryobiopsy, which has been generally used on peripheral lung lesions so far, is a feasible and safe approach for diagnosis and staging of mediastinal lymph nodal involvement, especially when station 7 is involved. Compared to EBUS TBNA, cryobiopsy might provide more adequate histological samples, with a possible impact on molecular characterizations and, therefore, therapeutic decisions. However, the learning curve of the procedure has not to be understated and optimal protocols for implementing this technique are needed. In our opinion, further studies designed to integrate the routine use of cryobiopsy in current practice for solid and eventually hematologic tumors with mediastinal lymph node involvement are warranted.

Pretracheal ectopic thymoma: A diagnostic challenge in endobronchial ultrasound-guided transbronchial needle aspiration cytology.

Ectopic thymomas (ETs) are rare thymic neoplasms that arise from atypical anatomical sites and present a diagnostic challenge for clinicians as they can be mistaken for other pathological entities on fine needle aspiration (FNA) cytology.

Pneumomediastinum: A Rare Complication of Endobronchial Ultrasound Guided Fine Needle Aspiration.

Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) is a commonly performed outpatient procedure used for the diagnosis, staging of lung cancer, and the evaluation of thoracic lymphadenopathy of unknown origin. With the advent of this minimally invasive technology, mediastinoscopy, once the gold standard, has fallen out of favour. Pneumomediastinum is a rare complication of EBUS-TBNA and can often be managed conservatively. We present a case of a 52-year-old female who developed pneumomediastinum following EBUS-TBNA and improved with expectant management in the emergency department. We discuss the proposed pathophysiology of this rare occurrence that usually follows a benign course. Severe complications, such as mediastinitis and tracheal tear, need to be excluded promptly.

PD-L1+ lung cancer stem cells modify the metastatic lymph-node immunomicroenvironment in nsclc patients.

INTRODUCTION: Cancer stem cells (CSCs) are implicated in tumor initiation and development of metastasis. However, whether CSCs also affect the immune system is not fully understood. We investigated correlations between the PD-L1+ CSCs, changes in T-cell phenotype in metastatic and non-metastatic lymph nodes (LNs) and response to treatment. METHODS: LNs' aspirates were obtained during the EBUS/TBNA procedure of 20 NSCLC patients at different stages of the disease. CSCs and T-cell characteristics were determined by flow cytometry. RESULTS: PD-L1+ CSCs positively correlated with the percentage of Tregs, PD-1+ CD4 T cells and Tim3+ CD4+ T cells, whereas PD-L1+ CSCs were negatively correlated with CD4+ T cells and CD28+ CD4+ T cells. The percentage of PD-L1+ CSCs was higher in patients with progressive disease (PD) as compared to patients with stable disease (SD) or partial response (PR). Among T cells, only PD-1+ CD4+ T cells and Tim3+ CD4+ T-cell frequencies were higher in patients with PD as compared to patients with SD or PR. CONCLUSION: The frequency of PD-L1+ CSCs associates with an altered T-cell frequency and phenotype indicating that CSCs can affect the immune system. The higher percentage of PD-L1+ CSCs in patients with PD may confirm their resistance to conventional therapy, suggesting that CSCs may be an interesting target for immunotherapy.

Impact of EBUS-TBNA in addition to [18F]FDG-PET/CT imaging on target volume definition for radiochemotherapy in stage III NSCLC.

PURPOSE/INTRODUCTION: [18F]FDG-PET/CT is the standard imaging-technique for radiation treatment (RT) planning in locally advanced non-small cell lung cancer (NSCLC). The purpose of this study was to examine the additional value of endobronchial-ultrasound transbronchial needle aspiration (EBUS-TBNA) to standard PET/CT for mediastinal lymph-node (LN) staging and its impact on clinical target volume (CTV). MATERIALS AND METHODS: All consecutive patients with primary stage III NSCLC who underwent [18F]FDG-PET/CT and EBUS-TBNA prior to RT were analyzed from 12/2011 to 06/2018. LN-stations were assessed by an expert-radiologist and a nuclear medicine-physician. CTV was evaluated by two independent radiation oncologists. LNs were grouped with increasing distance along the lymphatic chains from primary tumor into echelon-1 (ipsilateral hilum), echelon-2 (LN-station 7 and ipsilateral 4), and echelon-3 (remaining mediastinum and contralateral hilum). RESULTS: A total of 675 LN-stations of which 291 were positive for tumor-cells, were sampled by EBUS-TBNA in 180 patients. The rate of EBUS-positive LNs was 43% among all sampled LNs. EBUS-positivity in EBUS-probed LNs decreased from 85.8% in echelon-1 LNs to 42.4%/ 9.6% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher's exact test). The false discovery rate of PET in comparison with EBUS results rose from 5.3% in echelon-1 to 32.9%/ 69.1% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher's exact test). Sensitivity and specificity of FDG-PET/CT ranged from 85 to 99% and 67 to 80% for the different echelons. In 22.2% patients, EBUS-TBNA finding triggered changes of the treated CTV, compared with contouring algorithms based on FDG-avidity as the sole criterion for inclusion. CTV was enlarged in 6.7% patients due to EBUS-positivity in PET-negative LN-station and reduced in 15.5% by exclusion of an EBUS-negative but PET-positive LN-station. CONCLUSION: The false discovery rate of [18F]FDG-PET/CT increased markedly with distance from the primary tumor. Inclusion of systematic mediastinal LN mapping by EBUS-TBNA in addition to PET/CT has the potential to increase accuracy of target volume definition, particularly in echelon-3 LNs. EBUS-TBNA is recommended as integral part of staging for radiochemotherapy in stage III NSCLC.

High diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of adolescent pulmonary tuberculosis.

BACKGROUND: The microbiological diagnosis of pulmonary tuberculosis (Tb) in a pediatric population is hampered by both low pathogen burden and noncompliance with sputum sampling. Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been found useful for the evaluation of mediastinal pathologies in adults, for children, sparse data are available. Here, we have evaluated EBUS-TBNA as a diagnostic procedure in children and adolescents with suspected pulmonary Tb. METHODS: In this retrospective analysis, we reviewed the charts of unaccompanied refugee minors (URM) who were admitted between January 2016 and July 2018 and who, during their initial medical screening upon arrival in Germany, were found to have abnormal radiological pulmonary and mediastinal findings and/or immunological results indicative of Tb. For each patient, basic sociodemographic data, clinical features and data on diagnostic procedures performed were assessed. These included imaging, immunodiagnostic tests and microbiological data derived from sputum, bronchoalveolar lavage, EBUS-TBNA, bronchoscopy and pleural fluid sampling. All patients who underwent invasive sampling procedures were included in the study. RESULTS: Out of 42 URM with suspected Tb, 34 fulfilled the study's inclusion criteria. Ages ranged from 14 to 17 years. All were of African origin, with 70.0% coming from Somalia, Eritrea and Ethiopia. Among the 21 patients for whom EBUS-TBNA was performed, the diagnostic yield was high: 66.7% positive results (MTb detected either by acid-fast stain, culture or PCR in 4.8, 42.9 and 61.9% of samples, respectively). Multidrug-resistant MTb was found in two patients from Somalia. No complications were associated with the procedure. Overall, pulmonary Tb was diagnosed in 29 patients (85.3%), miliary Tb in two patients (5.9%) and latent Tb in three patients (8.8%). CONCLUSIONS: EBUS-TBNA is a sensitive and safe method with high diagnostic yield in the evaluation of pediatric patients with mediastinal pathology and suspected Tb.

Impact of 18F-FDG PET/CT, CT and EBUS/TBNA on preoperative mediastinal nodal staging of NSCLC.

BACKGROUND: Staging of non-small-cell lung cancer (NSCLC) is a multidisciplinary process involving imaging, endoscopic and surgical techniques. This study aims at investigating the diagnostic accuracy of 18F-FDG PET/CT, CT scan, and endobronchial ultrasound/transbronchial needle aspirate (EBUS/TBNA) in preoperative mediastinal lymph nodes (MLNs) staging of NSCLC. METHODS: We identified all patients who were diagnosed with NSCLC at the King Hussein Cancer Center in Amman, Jordan, between July 2011 and December 2017. We collected their relevant clinical, radiological, and histopathological findings. The per-patient analysis was performed on all patients (N = 101) and then on those with histopathological confirmation (N = 57), followed by a per-lymph-node-station basis overall, and then according to distinct N-stage categories. RESULTS: 18F-FDG PET/CT, in comparison to CT, had a better sensitivity (90.5% vs. 75%, p = 0.04) overall and in patients with histopathological confirmation (83.3% vs. 54.6%), and better specificity (60.5% vs. 43.6%, p = 0.01) overall and in patients with histopathological confirmation in MLN staging (60.6% vs. 38.2%). Negative predictive value of mediastinoscopy, EBUS/TBNA, and 18F-FDG PET/CT were (87.1%), (90.91%), and (83.33%) respectively. The overall accuracy was highest for mediastinoscopy (88.6%) and EBUS/TBNA (88.2%), followed by 18F-FDG PET/CT (70.2%). Dividing patients into N1 disease vs. those with N2/N3 disease yielded similar findings. Comparison between 18F-FDG PET/CT and EBUS/TBNA in patients with histopathological confirmation shows 28 correlated true positive and true negative findings with final N-staging. In four patients, 18F-FDG PET/CT detected metastatic MLNs that would have otherwise remained undiscovered by EBUS/TBNA alone. Lymph nodes with a maximal standardized uptake value (SUVmax) more than 3 were significantly more likely to be true-positive. CONCLUSION: Multimodality staging of the MLNs in NSCLC is essential to provide accurate staging and the appropriate treatment. 18F-FDG PET/CT has better overall diagnostic utility when compared to the CT scan. The NPV of 18F-FDG PET/CT in MLNs is reliable and comparable to the NPV of EBUS/TBNA. SUVmax of MLNs can help in predicting metastases, but nevertheless, a positive 18F-FDG PET/CT MLNs particularly if such a result would change the treatment plan, should be verified histopathologically.