A 52-year-old man was admitted to our hospital for mediastinal mass found incidentally in health examination. He had no special disease history or any symptoms. No face or upper extremity edema was found in physical examination. Enhanced chest computer tomography (CT) showed a size of 5.6*4.3 cm mass in anterior mediastinum, which was enhanced in the artery phase (Fig. ), and it had no clear boundary with left innominate vein and SVC. The CT report suggested high possibility of thymoma. Echocardiographic examination did not reveal any abnormality. Thymoma was diagnosed and he received operation in our hospital through median sternotomy on July 2019. During the operation, a dark red and saccular mass was found in anterior mediastinum with slight pulsation. The mass had no clear boundary with left innominate vein and further exploration revealed they were connected with each other. The membrane of the mass seemed to be very thin and easily bled when touched. Left innominate venous aneurysm with part of SVC involved was highly suspected.\nThe venous aneurysm was resected with the proximal and distal end of the left innominate vein blocked (Fig. ). However, the majority of the left innominate vein wall was involved and only a little part of vessel wall was left after the venous aneurysm was resected, which made the reconstruction of the left innominate vein necessary. Because of the misdiagnosis and lack of abundant preoperative preparation, we decided to take pericardium as material for repairment and reconstruction. We first resected the involved part of SVC with it blocked, and repaired it with a small piece of pericardium. The SVC was unblocked immediately after repairment was finished. Then we took a large piece of pericardium and wrapped it around a needle tube, suturing the two sides to make it a tube in shape with the smooth surface inside (Fig. ). The tube was first anastomosed to the distal end of the left innominate vein. Then we blocked the SVC again and opened a small hole in the side wall and anastomosed the other side of the tube with SVC. The reconstructed left innominate vein and SVC seemed patent and firm (Fig. ). Low molecular heparin was used once per day just for routine anticoagulation after surgery. The patient had an uneventful postoperative course and was discharged 6 days after surgery. He did not take anticoagulant drugs after discharge and was satisfied with the treatment therapy. The pathological diagnosis was mediastinal hemangioma. The patient kept in good condition on the last follow up date of December 2019.
A 58 years-old man presented at our emergency room with fever, cough and left thoracic pain. His past medical history was unremarkable. Blood test showed WBC and C-reactive protein elevation. He had started antibiotics therapy and, given the persistence of symptoms, CT scan was performed showing lower left pneumonia. Incidentally, a 2.5 cm mass was found in the upper anterior mediastinum, with positive contrast enhancement and a 5 mm vessel arising from left brachio-cephalic vein (, ). Because of size and position fine needle aspiration nor anterior mediastinotomy were performed. Radiologic features were consistent with thymoma that usually appears as an ovoid or lobulated, smooth, well-marginated mass, projecting over the mediastinum typically protruding unilaterally, therefore patient underwent (1) neurologic evaluation that excluded myasthenia (2) PET/CT scan that showed the absence of any pathological uptake. However, thymoma was felt to remain a diagnostic possibility and patient was referred for radical surgery, with particular attention to abnormal vascularization. He underwent left thoracoscopy and, in spite of extreme attention, during pleural dissection between mediastinum and sternum, a sudden massive bleeding occurred (about 1,500 cc) requiring emergency conversion to median sternotomy. It was then clear that the bleeding came from tumor and not from brachiocephalic vein or its branches, as initially thought. After controlling the bleeding, we removed the mass but it was necessary to sacrifice the left laryngeal nerve.\nIntra-operative emergency required significant blood transfusions and precautionary transfer in intensive care for 24 h. The patient eventually made a complete recovery. We only recorded transitory dysphonia as in case of laryngeal nerve paralysis. At specimen analysis, the cut surface seemed to have some fresh blood and the soft tissue was taupe with multifocal thrombosis in various stages of organization up to phlebolithes. Histopathologically, it was diagnosed a residual thymic tissue surrounded by lipomatous hyperplasia with venous malformation consisting essentially of a large number of dilated vessels with a single layer of endothelial cells with no signs of atypia or mitosis. Most of the channels contained red blood cells in the cavity. Margins were free. Definitive histology was a 7 cm fatty specimen enclosing a 2.5 cm in size mass diagnostic for residual thymus associated with venous vascular malformation (ISSVA classification, 2008).