[Thymic lesions: A 4 years-review]

The difficulty in differentiating invasive from non-invasive thymic tumours solely by histological features, leads to the decision of resecting suspected lesions except in the presence of: (a) diffuse metastasis; or (b) typical imaging findings of thymic hyperplasia or after recovering from some recent stress. Therefore, the role of radiology is of the utmost importance in the initial evaluation and staging of thymic mediastinal masses.

The objective of this study was to elaborate a retrospective analysis of the cases of thymic lesions that underwent surgery at the Cardiothoracic Department of Centro Hospitalar Vila Nova de Gaia/Espinho (CHVNG/E), from January 2013 to December 2016, illustrating their main radiologic findings with computed tomography (CT) images.

During the studied time period, 35 patients were diagnosed with thymic lesions including: 14 thymomas (40%), 9 thymic cysts (26%), 4 thymic hyperplasias (11%), 3 thymic carcinomas (9%), 2 thymolipomas (6%), 2 lymphomas (6%) and 1 neuroendocrine tumour (3%). The mean age of the sample was 60 years, ranging from 23 to 88 years, with a predomi- nance of the female sex (69%). In this article, 11 CT images and 1 thoracic x-ray are presented to illustrate the common imaging features of each thymic disease. Thymoma was the most frequent thymic lesion found in our 4-year case sample, similarly to what is described in literature for the adult age.

Knowledge of the main radiologic findings of each pathological entity of the thymus is vital for the correct therapeutic management and disease staging, frequently allowing the differentiation of non-surgical from surgical lesions.