Pyrexia of Unknown Origin in a Young Male: Unmasking Melioidosis in a Tuberculosis-Endemic Setting.

A young male, plantation worker from Southeast Asia, presented with a non-productive cough, intermittent high-grade fever with chills, and significant weight loss over two months. Prior investigations were non-contributory, despite various antibiotics, his symptoms persisted. Physical examination and routine investigations, including an extensive microbiological workup for fever were non-contributory. A positron emission tomography-computed tomography (PET-CT) scan performed for pyrexia of unknown origin (PUO) revealed pulmonary consolidation, mediastinal lymphadenopathy, and splenic microabscesses. Material aspirated via endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) from the left interlobar lymph node was positive for Burkholderia pseudomallei on conventional nested polymerase chain reaction (PCR), confirming a diagnosis of melioidosis. Following appropriate antibiotic therapy, there was a complete resolution of symptoms. This case underscores the diagnostic challenges and the need for advanced techniques in identifying melioidosis, which can mimic tuberculosis.

EBUS-TBNA diagnosis of mediastinal melioidosis in patient presented with lymphadenopathy and SVC thrombosis: A rare manifestation in non-diabetic patient.

Melioidosis is a tropical infectious disease that ranks as northeastern Thailand's third most common infectious cause of death. The manifestations of melioidosis vary depending on the organs involved and often resemble malignancy and tuberculosis. We present a case of an atypical melioidosis presentation in a patient with low-grade fever and facial swelling without any risk factors. Chest CT revealed a 3.3-cm heterogeneous enhancing right lower paratracheal lymph nodes with thrombosis of the superior vena cava and azygos vein. Endobronchial ultrasound-guided transbronchial needle aspiration of lymph node was performed, and Burkholderia pseudomallei was identified through lymph node culture. The patient underwent a three-week intravenous course of ceftazidime and a 12-week oral course of trimethoprim-sulfamethoxazole. Oral anticoagulation was also administered. Follow-up computed tomography of the thorax after completion of treatment revealed no residual lymphadenopathy and thrombosis.

Importance of mediastinal granulomatous/sarcoid-like lymphadenopathy in extrathoracic malignancies.

BACKGROUND: In patients with extrathoracic malignancies (ETM), granulomatous lymph adenopathy called sarcoid-like reactions (SLR) can be seen in the regional or draining lymph nodes. We hypothesized that SLR may be a sign of imminent metastasis and investigated the clinical course and rate of recurrence in patients with ETM and granulomatous mediastinal lymphadenopathy (MLN). METHODS: In this retrospective observational study, we reviewed the medical files of patients with known ETM and who underwent EBUS-TBNA for initial staging or detection of recurrence from 2011 to 2023. Patients with granulomatous MLN were included. RESULTS: Forty-one patients (29 female) enrolled in the study. Breast and colorectal carcinomas were the most common malignancies. A total of 81 lymph nodes were sampled. The final diagnosis of patients was five sarcoidosis, one tuberculosis, one second primary, one drug reaction, and 33 SLR. Among patients with SLR, in one patient lymph nodes progressed during the follow-up and were accepted as false-negative without confirmatory biopsy. The negative predictive value (NPV) of granulomatous MLN for metastasis was 97.05%. CONCLUSION: Granulomatous MLN may be due to tuberculosis, drug reaction, sarcoidosis, or SLR in patients with ETM. SLR has a high NPV in patients with ETM. Follow-up imaging rather than confirmatory biopsy is reasonable in these patients.

Intrathoracic non-tuberculous mycobacteriosis with endobronchial lesion in a child aged 11 with HIV infection diagnosed by bronchoscopic biopsy, EBUS-TBNA and confocal laser endomicroscopy.

The diagnosis of intrathoracic non-tuberculous mycobacteriosis (NTM) is challenging. We report a case of a pediatric pulmonary NTM with endobronchial lesion and lymphadenitis in a child with HIV infection diagnosed by bronchoscopic biopsy, EBUS-TBNA and probe-based confocal laser endomicroscopy (pCLE). The pCLE showed a large number of highly fluorescent cells and zones of density and disorganized elastin fibers at alveolar areas. A combination of diagnostic endoscopic procedures is required to establish the diagnosis of NTM.

Endobronchial ultrasound-guided cryobiopsy for diagnosing a case of granulomatosis with polyangiitis.

EBUS-TBNA has represented a revolution in the diagnosis of intrathoracic pathologies, particularly in lung cancer staging, replacing more invasive methods such as mediastinoscopy. However, its role in diagnosing rare benign or malignant mediastinal disorders is still a matter of debate. Over the past few years, the role of EBUS-guided cryobiopsy has been increasingly emerging as an innovative and minimally invasive technique in diagnosing these disorders, with an excellent safety profile. In this case report, we present the case of a young man brought to our attention after already undergoing a non-diagnostic trans thoracic needle aspiration (TTNA) procedure for lung consolidations. In our department, he underwent an initial EBUS-TBNA procedure with inconclusive rapid on-site evaluation (ROSE), leading to the decision to perform an EBUS-guided cryobiopsy, which yielded a diagnosis of granulomatosis with polyangiitis without complications. This clinical case demonstrates that in specific contexts, EBUS-cryobiopsy represents an excellent diagnostic tool.

Supernatant fluid from endobronchial ultrasound-guided transbronchial needle aspiration for rapid next-generation sequencing.

INTRODUCTION: There is an increasing demand to optimize the workflow and maximize tissue available for next-generation sequencing (NGS) for non-small cell carcinoma. We looked at transbronchial needle endobronchial ultrasound-guided bronchoscopy with transbronchial needle aspiration samples and evaluated the performance of supernatant (SN) fluid processed from a dedicated aspirate collected for NGS testing. MATERIALS AND METHODS: Nineteen samples were collected and processed using a new workflow. Five aspirates were collected in formalin. One additional dedicated pass was collected fresh and centrifuged. The resulting cell pellet was added to formalin for cell block (CB) processing. DNA and RNA were extracted from concentrated SN for targeted testing using the Oncomine Precision Assay (Thermo Scientific, Waltham, MA). NGS results from the corresponding CB samples were used as "controls" for comparison. RESULTS: Thirty-one mutations were detected in SN (Table 1). The most frequently mutated genes were TP53 (35%), EGFR (23%), KRAS (13%), CTNNB1 (6%), and ERBB2 (6%). There was 100% concordance between the mutations detected in SN and corresponding CBs with comparable variant allele frequencies. Turnaround time of NGS results was 1 day for SN compared to 4-10 days for CB. CONCLUSIONS: We were able to demonstrate the usefulness of SN for reliable rapid molecular results. We successfully incorporated the workflow for tissue handling and processing among our clinical, cytopathology, and molecular teams. Molecular results were available at the same time as the cytologic diagnosis, allowing for timely reporting of a comprehensive diagnosis. This approach is particularly useful in patients with advanced disease requiring urgent management.

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.

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).

Quantitative evaluation of endobronchial ultrasound elastography in the diagnosis of benign and malignant mediastinal and hilar lymph nodes.

OBJECTIVE: To compare the diagnostic value of different quantitative methods of endobronchial ultrasound elastography in benign and malignant mediastinal and hilar lymph nodes. METHODS: This retrospective study included patients who underwent endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal and hilar lymph node enlargement in our hospital between January 2019 and August 2022. We compared different quantitative elastography parameters [red area ratio (RAR, lymph node red area/lymph node area), green area ratio (GAR, lymph node green area/lymph node area), blue area ratio (SAR, lymph node blue area/lymph node area), mixed area ratio (MAR, lymph node green area/lymph node area), blue-green lymph node area/lymph node area), strain rate ratio (SR), strain rate in the target lymph node (LPA), ratio of blue area to total lymph node area outside the center of the target lymph node (PAR), and average grey value (MGV)], in order to find the best quantitative evaluation method. RESULTS: A total of 244 patients (346 lymph nodes) were included in this study. All quantitative elastography parameters were statistically significant for the differentiation of benign and malignant lesions except the average grey value of the target lymph nodes. The area under the receiver operating characteristic curve of SAR was 0.872 (95% confidence interval: 0.83-0.91), the cutoff value was 0.409, and the sensitivity, specificity, positive and negative predictive values were 85.4%, 78.0%, 80.4%, and 83.4%, respectively. CONCLUSION: Compared with other types of quantitative analysis, SAR has a higher predictive significance for benign and malignant lymph nodes.

Bacterial pericardial effusion secondary to endobronchial ultrasound guided needle aspiration.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a widely used procedure in lung cancer diagnosis with few serious complications. We present a rare case of pericardial effusion secondary to EBUS-TBNA. An 80-year-old male with interstitial lung disease, developed a pericardial effusion composed exclusively of oropharyngeal flora following EBUS-TBNA. Bacterial pericardial effusion following EBUS-TBNA has only been reported in the literature seven previous times. The majority of these cases reported a biopsy of the 4R lymph node. This case highlights the potential risk of pericardial effusion when sampling lymph nodes, particularly station 4R, in patients with a high-riding superior pericardial recess.

Accuracy of endobronchial ultrasound-guided transbronchial needle aspiration for staging of non-small cell lung cancer.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is routinely performed to confirm a lung cancer diagnosis and/or to clinically stage disease. EBUS-TBNA findings may be used to determine whether patients can be offered potentially curative surgery. In this study, we evaluated the reporting in our service of EBUS-TBNA cytology for early-stage (operable) non-small cell lung cancer (NSCLC), focusing on diagnostic accuracy and analyzing cases with discordant cytologic and post-surgical histopathologic conclusions. METHODS: Cytology slides and cytopathology reports of 120 NSCLC patients who had undergone EBUS-TBNA and lobectomy in our hospital system between 2015 and 2021 were retrospectively reviewed. RESULTS: Of 290 lymph nodes (110 cases) able to be reviewed, interpretation of 48 lymph nodes was discordant with the original cytopathology report. This included 31 lymph nodes originally reported as adequate, which were found to be non-diagnostic on review. The diagnostic accuracy (benign/malignant) of lymph nodes that were sampled at EBUS-TBNA and excised at surgery was 89%. Specific examination of cases where EBUS-TBNA cytology did not reflect post-surgical findings illustrated important features and limitations of the procedure. These included potential misclassification of lymph node stations, the presence of multiple, variably involved nodes at lymph node stations, and the failure to detect small volume disease. CONCLUSIONS: Continuous evaluation of EBUS-TBNA performance identifies technical limitations and areas of improvement for cytopathology reporting. This is increasingly important in an era where lung cancer screening is expected to increase diagnosis of early-stage disease and with the advent of novel treatments, including non-surgical management options.

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.

Factors associated with increased diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration: an observational single center study.

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an innovative tool for diagnosing mediastinal diseases. We investigated the factors affecting the diagnostic yield of EBUS-TBNA and evaluated whether the effects of these factors (number of biopsies, core tissue acquisition rate, and diameter and volume of tissue) vary depending on computed tomography (CT) and/or positron emission tomography (PET)/CT results. Methods: We retrospectively analyzed lung cancer patients who underwent EBUS-TBNA at Korea University Ansan Hospital (January 2019-December 2022). Patients in whom EBUS-TBNA failed and those with missing diameter or volume data and no imaging data interpretation were excluded. Subgroup analysis was performed by dividing the patients into None (no cancer detected on CT or PET/CT), Either (cancer detected on either CT or PET/CT), and Both (cancer detected on both CT and PET/CT) groups. Results: In all, 228 patients were enrolled; 351 lymph node stations were analyzed. The median age of the patients was 69 years (male, 76.8%). Adenocarcinoma (28.5%) was the most common diagnosis. EBUS-TBNA was predominantly performed at station #4R (30.5%). Each examination involved two stations with a total procedure time of 30 minutes. An increased number of passes led to a higher diagnostic yield for EBUS-TBNA (P<0.001). Additionally, successful tissue sampling was associated with a large diameter (P=0.016) and volume (P=0.002) of the tissue. The effect of these factors was modified by imaging results. In the None and Either groups, an increase in the pass number was correlated with an increased diagnostic yield (adjusted P=0.003 and 0.007, respectively). However, in the Both group, it was not significant and remained at a suggestive level (P=0.304). The diameter and volume did not differ significantly across subgroups (adjusted P>0.05). Conclusions: Increasing the number of passes during EBUS-TBNA can maximize the diagnostic yield, especially when CT and/or PET/CT results are inconclusive.

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.

EBUS-guided cryobiopsy in the diagnosis of thoracic disorders.

BACKGROUND: Endobronchial Ultrasound (EBUS) has emerged as a crucial tool for diagnosing intrathoracic disorders, particularly in the staging of lung cancer. However, its diagnostic capabilities in the context of benign and rare diseases remain a subject of debate. AIM: to investigate the diagnostic yield and safety of EBUS-transbronchial mediastinal cryobiopsy (EBUS-TMC) in comparison to EBUS-transbronchial needle aspiration (TBNA) for a broad spectrum of intrathoracic diseases. METHODS: a single-centre retrospective observational study conducted on 48 patients who underwent both EBUS-TBNA and endobronchial ultrasound-transbronchial mediastinal cryobiopsy (EBUS-TMC) in the same procedure between August 2021 and October 2023. RESULTS: The overall diagnostic yield of EBUS-TMC surpassed that of EBUS-TBNA (95.8% vs 54.1 %), notably excelling in the diagnosis of sarcoidosis (92.8% vs 78.5 %), rare mediastinal disorders (100% vs 0 %), hyperplastic lymphadenopathy (100% vs 0 %), and lymphoproliferative disease (100% vs 0 %). No significant differences were observed in the diagnosis of NSCLC and SCLC. Samples obtained through EBUS-TMC facilitated the acquisition of NGS and immunohistochemical analyses more readily. CONCLUSION: EBUS-TMC may contribute to the precise diagnosis and subtyping of mediastinal diseases, especially lymphomas and rare mediastinal tumors, thereby reducing the number of non-diagnostic procedures.

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.