Medulloblastoma in the cerebellopontine angle mimicking a schwannoma

Abstract

The typical distinction between cerebellopontine angle (CPA) medulloblastoma and other primary CPA tumors was not fully known. While CPA medulloblastoma is very uncommon, it should be included in the differential diagnosis of patients with CPA tumors.

Keywords: cerebellopontine angle; children; extra‐axial; medulloblastoma.

FIGURE 1

A homogeneously hyperintense solid mass located in the right CPA, on axial T2‐weighted image (arrow, A). The mass appears isointense in coronal FLAIR imaging (arrow, B), hyperintense on axial DWI imaging (arrow, C), and hypointense on the axial ADC map (arrow, D)

FIGURE 2

Intravoxel incoherent motion analysis for the tumor and parenchyma

FIGURE 3

The FA values for the tumor and the parenchyma on diffusion tensor imaging

FIGURE 4

Perfusion analysis for the tumor and the parenchyma on the semiquantitative T1‐perfusion map

FIGURE 5

Metabolic parameters of the tumor based on MRI spectroscopy

FIGURE 6

Histopathological results showing (A) densely packed small‐blue‐round cells and (B) embryonal cells with Homer Wright rosettes, accompanied by (C) high mitotic activity (hematoxylin and eosin staining, original magnification [A], ×100 [B], and ×400 [C])