Mediastinal venolymphatic malformations mimicking thymic carcinoma

This report was about a 60‐year‐old asymptomatic female patient who presented to our clinic with an anterior mediastinal mass found on routine chest computed tomography (CT). Chest CT revealed an irregular poorly enhanced anterior mediastinal mass which showed signs of infiltration to adjacent structures with sparse calcifications. The preliminary diagnosis was thymic carcinoma. The patient underwent extended thymectomy via median sternotomy and complete excision of the tumor. A small draining vein to the left brachiocephalic vein and phleboliths were identified in the tumor. A definitive diagnosis was made of mediastinal venolymphatic malformation (VLM). The patient had an uneventful clinical course and was discharged without further complication. This report highlights that it is possible to misdiagnose mediastinal VLM as thymic carcinoma and could serve as a useful reminder to physicians in the future.