The Distribution of Mediastinal Lesions across Multi Institutional, International, Radiology Databases.
BACKGROUND Mediastinal lesions are uncommon; studies on their distribution are in general small and from a single institution. Furthermore, these studies are usually based on pathology or surgical databases and therefore miss many lesions that are not biopsied and/or resected. Our aim was to identify the distribution of lesions in the mediastinum in a large international, multi institutional cohort. MATERIAL AND METHODS At each participating institution, a standardized retrospective radiology database search for interpretations of CT, PET CT and MRI scans including any of the following terms: "mediastinal nodule" "mediastinal lesion" "mediastinal mass" or "mediastinal abnormality" was performed (2011 2014) Standardized data were collected. Statistical analysis was performed. RESULTS Amongst 3,308 cases, thymomas (27.8% benign mediastinal cysts (20.0% and lymphomas (16.1% were most common. The distribution of lesions varied amongst mediastinal compartments; thymomas (38.3% benign cysts (16.8% and neurogenic tumors (53.9% were the most common lesions in the prevascular, visceral and paravertebral mediastinum, respectively (p<0.001) Mediastinal compartment was associated with age; patients with paravertebral lesions were the youngest (p<0.0001) Mediastinal lesions differed by continent/country with benign cysts being the most common mediastinal lesions in China, thymomas in Europe and lymphomas in North America and Israel (p<0.001) Benign cysts, thymic carcinomas, and metastases were more commonly seen in larger hospitals, while lymphomas and thymic hyperplasia occurred more often in smaller hospitals (p<0.01) CONCLUSIONS Our study confirmed that spectrum and frequency of mediastinal lesions depends on mediastinal compartment and age. This information provides helpful demographic data and is important when considering the differential diagnosis of a mediastinal lesion.
Journal of thoracic oncology official publication of the International Association for the Study of Lung Cancer