Multidimensional evaluation of tracheobronchial disease in adults

Abstract

The large airways can be affected by a wide spectrum of acquired benign and malignant diseases. These lesions may present as focal or diffuse processes and with narrowing or widening of the airway. Some of these may be asymptomatic for quite some time and may be incidentally detected on imaging, while others may be symptomatic, causing airway compromise. There may be a characteristic radiograph and computed tomography (CT) appearance, suggesting a narrow differential. When the imaging findings are not definitive, tissue may be obtained for pathological analysis. It behooves the radiologist to be familiar with the pathologic findings that correlate with the radiographic or CT appearance of the most frequently seen large airway lesions. In this way, we may improve our diagnostic accuracy. This paper will present the imaging findings of the most prevalent tracheobronchial lesions along with any associated pathology.Teaching Points• The large airways can be affected by many acquired benign and malignant diseases.• Large airway lesions may present as focal or diffuse processes, with narrowing or widening.• There may or may not be characteristic imaging appearance of large airway disease.• If imaging findings are not definitive, tissue may be obtained for pathological analysis.

CT Findings of Central Airway Lesions Causing Airway Stenosis-Visualization and Quantification: A Pictorial Essay

“…About one-third of patients have either mediastinal or pulmonary metastases at diagnosis. In addition, approximately 40% of tracheobronchial SCCs are reported to have an association with carcinoma of the oropharynx, larynx, and lung ( 3 9 12 ).…”

“…The majority of SCCs in the tracheobronchial tree show high uptake of fluorine-18-fluorodeoxyglucose ( 18 F-FDG) in PET/CT. Approximately 10% of lesions are multifocal, which necessitates a careful evaluation of the remainder of the airway when SCC is suspected ( 3 9 12 ).…”

“…Because of its submucosal origin, ACC tends to have an intact epithelium and a smooth contour. Pathologically, these tumors resemble glandular tissue, as they arise from minor salivary glands ( 3 9 12 ).…”

“…Since most ACCs manifest as central airway tumors, they should be distinguished from bronchogenic carcinoma (e.g., SCC), carcinoid tumor, and benign airway tumors. When ACCs occur in the central airways and show avid FDG uptake it is difficult to differentiate them from bronchogenic carcinoma, particularly SCC ( 3 9 12 ).…”

“…Patients are usually in their third to fifth decade, and commonly present with symptoms related to airway involvement, such as asthma, cough, dyspnea, and hemoptysis. As the majority of tumors arise in or close to the central airways, airway obstruction can occur resulting in atelectasis or recurrent postobstructive pneumonia in the same lobe ( 3 9 12 ).…”