Imaging of intravenous lobular capillary hemangioma of azygos vein.

Intraluminal masses of the azygos vein are of rare occurrence. The differential diagnosis includes bland thrombus, tumor thrombus, epithelioid hemangioendothelioma, and leiomyosarcoma. To this list, the authors add an uncommon case of intravenous lobular capillary hemangioma, also known as intravenous pyogenic granuloma, of the azygos vein, inducing a recurrent large right pleural effusion. CT, MR, and PET/CT features of this lesion are presented.