Thymic haemangioma presenting with a left innominate vein aneurysm: insight into the aetiology

Abstract

Thymic haemangiomas and innominate vein aneurysms are rare with only 7 and 19 previous cases, respectively, reported in the medical literature. The aetiology of an innominate vein aneurysm remains unclear and there is no previous report of tumour involvement. We present the case of a 27-year old male with concomitant mediastinal tumour and innominate vein aneurysm who underwent surgical treatment. The tumour intruded into the lower section of the innominate vein, thus causing aneurysmal dilation. Pathologically, the tumour was diagnosed as a thymic cavernous haemangioma involving the left innominate vein. This is the first case of a thymic haemangioma presenting with an innominate vein aneurysm, and suggests that tumours may be involved in the aetiology of innominate vein aneurysms.

Thymic Cavernous Hemangioma With a Left Innominate Vein Aneurysm

“…Aneurysms may also occur secondary to arteriovenous fistulae [2,6]. We previously reported that a thymic cavernous hemangioma may be included in the etiology of an innominate vein aneurysm because the tumor may retract the lower portion of the left innominate vein [2]. Compared with our previous case, which had a convex-shaped left innominate vein aneurysm, our current case had a fusiform-shaped left innominate vein aneurysm.…”

“…Furthermore, a coexisting left innominate vein aneurysm was discovered. Innominate vein aneurysms are also rare, with only 20 cases reported to date [2]. Therefore, a thymic cavernous hemangioma with a left-side innominate vein aneurysm, as in our case, is very rare.…”

“…A thymic hemangioma presenting with an innominate vein aneurysm is extremely rare, and this case was the first in 2012 and the second overall encountered in our institution [2].…”

“…The etiologies of thoracic venous aneurysms include congenital malformations, trauma, inflammation, infection, and degenerative changes in the vessel wall. Aneurysms may also occur secondary to arteriovenous fistulae [2,6]. We previously reported that a thymic cavernous hemangioma may be included in the etiology of an innominate vein aneurysm because the tumor may retract the lower portion of the left innominate vein [2].…”

“…Three-dimensional (3D) CT and a 3D model created using a 3D printer (Connex; Stratasys, Tokyo, Japan) showed abnormal dilation of the left innominate vein, which was partly covered by the tumor (Fig 2). We preoperatively diagnosed the mass as a thymic hemangioma based on our experience with a similar case [2]. Thymoma and thymic venous malformation were ruled out as other preoperative diagnoses.…”