New developments in the imaging of lung cancer.

Radiological and nuclear medicine methods play a fundamental role in the diagnosis and staging of patients with lung cancer. Imaging is essential in the detection, characterisation, staging and follow-up of lung cancer. Due to the increasing evidence, low-dose chest computed tomography (CT) screening for the early detection of lung cancer is being introduced to the clinical routine in several countries. Radiomics and radiogenomics are emerging fields reliant on artificial intelligence to improve diagnosis and personalised risk stratification. Ultrasound- and CT-guided interventions are minimally invasive methods for the diagnosis and treatment of pulmonary malignancies. In this review, we put more emphasis on the new developments in the imaging of lung cancer.

Bronchoscopic procedures to diagnose peripheral lung lesions.

Bronchoscopy has a low risk of complications when diagnosing peripheral lung lesions suspected of malignancy, however the procedures do not always determine a diagnosis. Several modalities have been invented to improve the diagnostic yield, including radial endobronchial ultrasound and electromagnetic navigation, which are currently used by several departments in Denmark. Augmented fluoroscopy, CT-guided bronchoscopy and robotic bronchoscopy are not yet available in Denmark, but may improve the diagnostic work-up, as argued in this review.

Management of incidental pulmonary nodules in CT examination.

Lung cancer is the leading cause of cancer-related death in Denmark and the world. The increase in CT examinations has led to an increase in detection of pulmonary nodules divided into solid and subsolid (including ground glass and part solid). Risk factors for malignancy include age, smoking, female gender, and specific ethnicities. Nodule traits like size, spiculation, upper-lobe location, and emphysema correlate with higher malignancy risk. Managing these potentially malignant nodules relies on evidence-based guidelines and risk stratification. These risk stratification models can standardize the approach for the management of incidental pulmonary findings, as argued in this review.

ERS International Congress 2023: highlights from the Clinical Techniques, Imaging and Endoscopy Assembly.

The Clinical Techniques, Imaging and Endoscopy Assembly is involved in the diagnosis and treatment of several pulmonary diseases, as demonstrated at the 2023 European Respiratory Society (ERS) International Congress in Milan, Italy. From interventional pulmonology, the congress included several exciting results for the use of bronchoscopy in lung cancer, including augmented fluoroscopy, robotic-assisted bronchoscopy and cryobiopsies. In obstructive lung disease, the latest results on bronchoscopic treatment of emphysema with hyperinflation and chronic bronchitis were presented. Research on using cryobiopsies to diagnose interstitial lung disease was further explored, with the aims of elevating diagnostic yield and minimising risk. For imaging, the latest updates in using artificial intelligence to overcome the increased workload of radiologists were of great interest. Novel imaging in sarcoidosis explored the use of magnetic resonance imaging, photon-counting computed tomography and positron emission tomography/computed tomography in the diagnostic work-up. Lung cancer screening is still a hot topic and new results were presented regarding incorporation of biomarkers, identifying knowledge gaps and improving screening programmes. The use of ultrasound in respiratory medicine is an expanding field, which was demonstrated by the large variety in studies presented at the 2023 ERS Congress. Ultrasound of the diaphragm in patients with amyotrophic lateral sclerosis and myasthenia gravis was used to assess movements and predict respiratory fatigue. Furthermore, studies using ultrasound to diagnose or monitor pulmonary disease were presented. The congress also included studies regarding the training and assessment of competencies as an important part of implementing ultrasound in clinical practice.

Radial Endobronchial Ultrasound and Electromagnetic Navigation Bronchoscopy with Fluoroscopy for the Diagnosis of Peripheral Lung Lesions.

Diagnosing lung cancer using a flexible bronchoscope is a safe procedure with a very low risk of complications. Bronchoscopy has high diagnostic accuracy for endobronchial lesions, but it falls short when sampling peripheral lesions. Therefore, several modalities have been invented to guide the bronchoscope to the lesion and confirm the location of the tumor before tissue sampling. Fluoroscopy is used during bronchoscopy to provide a 2D X-ray image of the thorax during the procedure. The bronchoscope and tools will be visible, as well as lesions if larger than 2.0-2.5 cm. Radial endobronchial ultrasound (rEBUS) consists of an ultrasound probe, small enough to be inserted into the working channel of the bronchoscope. The ultrasound probe is used to differentiate between consolidated tissue, such as tumor tissue, and normal air-filled lung parenchyma. Electromagnetic navigation bronchoscopy (ENB) creates a 3D model of the bronchial tree from computed tomography (CT) scans of the patient. Prior to the bronchoscopy, a route from the trachea to the lesion is planned, to create real-time guidance of the bronchoscope to the lesion during the procedure, similar to the Global Positioning System. The aim of this article is to describe a stepwise approach to performing bronchoscopy with rEBUS and fluoroscopy, bronchoscopy with ENB, rEBUS, and fluoroscopy. In the discussion section, the pros and cons of each modality will be discussed.

A Stepwise Approach for Performing Ultrasound Guided Transthoracic Lung Biopsy.

Diagnosing patients with radiological lung lesions, especially those suspected of having primary lung cancer, is a common and critical clinical scenario. When selecting the most suitable invasive procedure to establish a diagnosis in these cases, a delicate balance must be struck between achieving a high diagnostic yield, providing staging information, minimizing potential complications, enhancing the patient experience, and controlling costs. The integration of thoracic ultrasound as a routine clinical tool in respiratory medicine has led to increased awareness and utilization of ultrasound-guided invasive techniques in chest procedures, including transthoracic biopsies. By following a systematic and stepwise approach, transthoracic ultrasound-guided lung biopsy emerges as a safe, cost-effective procedure with a remarkable diagnostic accuracy. These attributes collectively position it as an ideal invasive technique when technically feasible. Consequently, in patients presenting subpleural lung lesions suspected of malignancy, transthoracic ultrasound-guided lung biopsy has become a standard procedure in the realm of modern invasive pulmonology.

Endobronchial Ultrasound for the Screening of Pulmonary Embolism in Patients with Suspected Lung Cancer: A Prospective Cohort Study.

BACKGROUND: Patients with lung cancer exhibit increased risk of pulmonary embolism (PE). While the contrast phase of computed tomography of the chest in the diagnostic work-up of suspected chest malignancy does not allow reliable detection of PE, it may be feasible to screen for present PE during endobronchial ultrasound (EBUS) examination. OBJECTIVES: The aim of this study was to establish if screening during EBUS for PE in patients with suspected lung cancer is feasible and if positive findings are predictive of PE. METHODS: Patients undergoing EBUS due to suspicion of malignancy of the chest were prospectively enrolled. The pulmonary arteries were assessed during EBUS using a standardized protocol. Patients in whom PE suspicion was raised were referred to confirmatory imaging. RESULTS: From December 2020 to August 2021, 100 patients were included. Median time for vascular assessment during EBUS was 2 min (Q1-Q3: 1-3 min). EBUS identified two suspected PEs (2%), and the number needed to scan was 50. The positive predictive value of EBUS for PE was 100%. CONCLUSION: EBUS for PE screening seems feasible and with limited time use. The PPV of positive findings for the diagnosis of PE is high, but the utility is somewhat limited by a high number needed to scan even in a high-risk population. Based on our findings, we believe that EBUS assessment of the pulmonary vasculature may have a role as a routine screening tool for PE. The assessment for PE should be implemented in EBUS training programmes, as operators should be able to recognize incidental PEs.

Does the Addition of Radial Endobronchial Ultrasound Improve the Diagnostic Yield of Electromagnetic Navigation Bronchoscopy? A Systematic Review.

BACKGROUND: Lung cancer is the leading cause of cancer-related death worldwide. Early diagnosis is crucial to increased survival rates. Radial endobronchial ultrasound (rEBUS) and electromagnetic navigation bronchoscopy (ENB) have been developed for the diagnosis of small lung lesions. The aim of this systematic review was to evaluate whether the combination of rEBUS and ENB is superior to ENB alone. METHOD: A systematic search was performed using MEDLINE, Embase, and Cochrane Library databases on "ENB," and conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The project was registered with PROSPERO, number CRD42020214682. RESULTS: In total, 2,092 studies were identified through a literature search. Five studies were included in the final review. One study found that the addition of rEBUS increased diagnostic yield, while another concluded the converse. Three studies did not have significant results. Meta-analysis was not feasible due to heterogeneity and the small number of studies. CONCLUSION: As the current evidence on the topic is sparse and heterogeneous, it is not possible to conclude whether the addition of rEBUS to ENB has a significant impact on diagnostic yield. Further studies are needed to illuminate this question in order to ensure optimal choice of endoscopic technique as well as used time and resources. The project received funding from the Region of Southern Denmark's PhD fund.