Background Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has emerged as an important tool for the diagnosis and staging of lung cancer but its role in the diagnosis of tuberculous intrathoracic lymphadenopathy has not been established. The aim of this study was to describe the diagnostic utility of EBUS-TBNA in patients with intrathoracic lymphadenopathy due to tuberculosis (TB). Methods 156 consecutive patients with isolated intrathoracic TB lymphadenitis were studied across four centres over a 2-year period. Only patients with a confirmed diagnosis or unequivocal clinical and radiological response to antituberculous treatment during follow-up for a minimum of 6 months were included. All patients underwent routine clinical assessment and a CT scan prior to EBUS-TBNA. Demographic data, HIV status, pathological findings and microbiological results were recorded. Results EBUS-TBNA was diagnostic of TB in 146 patients (94%; 95% CI 88% to 97%). Pathological findings were consistent with TB in 134 patients (86%). Microbiological investigations yielded a positive culture of TB in 74 patients (47%) with a median time to positive culture of 16 days (range 3e84) and identified eight drug-resistant cases (5%). Ten patients (6%) did not have a specific diagnosis following EBUS; four underwent mediastinoscopy which confirmed the diagnosis of TB while six responded to empirical antituberculous therapy. There was one complication requiring an inpatient admission. Conclusions EBUS-TBNA is a safe and effective firstline investigation in patients with tuberculous intrathoracic lymphadenopathy.

Our current understanding of epidermal growth factor receptor (EGFR) autoinhibition is based on X-ray structural data of monomer and dimer receptor fragments and does not explain how mutations achieve ligand-independent phosphorylation. Using a repertoire of imaging technologies and simulations we reveal an extracellular head-to-head interaction through which ligand-free receptor polymer chains of various lengths assemble. The architecture of the head-to-head interaction prevents kinase-mediated dimerisation. The latter, afforded by mutation or intracellular treatments, splits the autoinhibited head-to-head polymers to form stalk-to-stalk flexible non-extended dimers structurally coupled across the plasma membrane to active asymmetric tyrosine kinase dimers, and extended dimers coupled to inactive symmetric kinase dimers. Contrary to the previously proposed main autoinhibitory function of the inactive symmetric kinase dimer, our data suggest that only dysregulated species bear populations of symmetric and asymmetric kinase dimers that coexist in equilibrium at the plasma membrane under the modulation of the C-terminal domain.

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Lung cancer diagnostics have progressed greatly in the previous decade. Development of molecular testing to identify an increasing number of potentially clinically actionable genetic variants, using smaller samples obtained via minimally invasive techniques, is a huge challenge. Tumour heterogeneity and cancer evolution in response to therapy means that repeat biopsies or circulating biomarkers are likely to be increasingly useful to adapt treatment as resistance develops. We highlight some of the current challenges faced in clinical practice for molecular testing of EGFR, ALK, and new biomarkers such as PDL1. Implementation of next generation sequencing platforms for molecular diagnostics in non-small-cell lung cancer is increasingly common, allowing testing of multiple genetic variants from a single sample. The use of next generation sequencing to recruit for molecularly stratified clinical trials is discussed in the context of the UK Stratified Medicine Programme and The UK National Lung Matrix Trial.

Rationale: The current management of lymphoma requires accurate diagnosis and subtyping of de novo lymphoma and of relapsed or refractory lymphoma in known cases. The role of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the clinical management of lymphomas is unclear. Objectives: To investigate the use of EBUS-TBNA in the diagnosis of de novo and relapsed mediastinal lymphomas. Methods: A total of 2,256 consecutive patients who underwent EBUS-TBNA in a tertiary center between February 2008 and April 2013 were prospectively evaluated. The diagnostic accuracy and clinical use of EBUS-TBNA in 100 cases of de novo or suspected relapsed mediastinal lymphoma was investigated by comparing EBUS-TBNA diagnosis with the final diagnosis. Measurements and Main Results: De novo mediastinal lymphoma was correctly diagnosed by EBUS-TBNA in 45 (88%) of 51 and relapsed lymphoma in 15 (100%) of 15 lymphoma cases. EBUS-TBNA accurately established a diagnosis other than lymphoma in 32 (97%) of 33 patients with suspected lymphoma relapse. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EBUS-TBNA in the diagnosis of mediastinal lymphoma were 89%, 97%, 98%, 83%, and 91%, respectively. Sensitivity of EBUS-TBNA in subtyping lymphomas into high-grade non-Hodgkin lymphoma, low-grade non-Hodgkin lymphoma, and Hodgkin lymphoma was 90%, 100%, and 79%, respectively. EBUS-TBNA diagnosis was adequate for clinical management in 84 (84%) of 100 cases. Conclusions: Multimodality evaluation of EBUS-TBNA can be successful in the diagnosis of de novo mediastinal lymphomas and is ideally suited in distinguishing lymphoma relapse from alternative pathologies; it is least sensitive in subtyping Hodgkin lymphoma.