Ruptured Tentorium Originating Masson Tumor

Abstract

Intravascular papillary endothelial hyperplasia (IPEH) also known as Masson's tumor, is a benign, slow growing, vascular lesion which is seen very rarely and only a few cases have been reported intracranially in the literature. It has been reported at many sites, but the posterior fossa involvement is very rare. The preoperative diagnosis is very difficult, as there is no enough cases to achieve a clear understanding about the details of its radiological findings. Differential diagnosis have to be made especially from angiosarcoma and meningioma. It is curable by total surgical removal. In this article we presented the characteristic clinical, radiological, perioperative and pathological findings in a case of IPEH in an unusual location, origin and behavior. To best of our knowledge, we presented the first case of IPEH originating from tentorium.

Keywords: Dural attachment; extraaxial lesion; intravascular papillary endothelial hyperplasia; posterior fossa tumor.

Figure 1

(a-d) Preoperative magnetic resonance images (a) axial unenhanced T2 weighted magnetic resonance imaging showing right-sided lesion (white arrow) and hyperdense areas which extends to the left cerebellum (hemorrhage) and there is no edema round the lesion. (b) Axial postcontrast T1 image, showing bilateral vermian lesions in which the right-sided mass is enhancing gadolinium peripherally. (c) Postcontrast sagittal image, demonstrating partly attachment of the mass to the tentorium. (d) Postcontrast coronal image demonstrates bilateral lesions close to the tentorium in mixt intensity

Figure 2

(a-d) Intraoperative images. (a) Initial surgical view of the tumor, originating from the tentorium (white arrow) after retraction of cerebellum inferiorly. (b) Bipolar coagulation of the tumor feeders and detachment of the tumor from the tentorium. (c) Surgical view of the tumor (white arrow) after total detachment. (d) Removal of the tumor in a single piece (white arrow) fashion

Figure 3

(a-c) Postoperative magnetic resonance images demonstrating no residual tumor. (a) Axial enhanced T1 imaging. (b) Sagittal enhanced T1 imaging. (c) Coronal T2 imaging

Figure 4

(a-c) Histopathological images. (a) Anomalous vascular channels, some of them are associated thrombus and fibrosis. Well circumscribed dilated large blood vessel containing papillary structures in the lesion is marked with an arrow, (H and E, ×40) (b) High magnification view of the (arrow) marked area. The delicate papillary structures are covered by a thin endothelial lining. No significant atypia, mitotic activity, or necrosis are seen, (H and E, ×100). (c) Strong immunopositivity for CD-31 in most of the endothelial cells lining small vessels and papillary structures CD31 ×100