case_images: PMC3268097_01
case_images: Preoperative magnetic resonance imaging demonstrating a cystic-solid mass of brainstem with mild edema. The solid part manifested homogeneous enhancement on T1-weighted gadolinium enhancement (thick arrow). The well-defined mass was mainly located in pons with the cystic part (thin arrow) extending to the right cerebral peduncle, but there was no evidence of attachment to dura mater. Axial T1-weighted imaging (A), coronal (B) and sagittal (C) post-contrast T1-weighted imaging.
case_images: 1477-7819-10-10-1.jpg
case_images: PMC3268097_01_1477-7819-10-10-1.jpg
case_images: F1
case_images: T1- and T2- weighted imaging with homogeneous enhancement on T1-weighted gadolinium enhancement, but no dural tail sign was noted. The cystic part was shown of hypo-intense on T1-weighted imaging and hyper-intense on T2-weighted imaging (Figure 1).
case_images: Photomicrographs showing the histological and immunohistochemical features of the lesion. The tumor tissue was composed of sheets of cells arranged in a predominantly papillary pattern with perivascular pseudo-rosettes. Tumor cells in the papillary area displayed abundant eosinophilic cytoplasm, vesicular nuclei (A) (original magnification x100). The immunohistochemistry profile showed positivity for EMA (B), vimentin (C) and MIB-1 (D) (original magnification x200). The insert in A represents a higher magnification of the outlined area (original magnification x400).
case_images: 1477-7819-10-10-2.jpg
case_images: PMC3268097_01_1477-7819-10-10-2.jpg
case_images: F2
case_images: The immunohistochemistry profile showed positivity for epithelial membrane antigen (EMA) and vimentin, but negativity for glial fibrillary acidic protein (GFAP), cytokeratin (CK), and S-100 protein (Figure 2).
case_images: Nine-month after the first operation, magnetic resonance imaging revealed a local recurrence of primary tumor, which showed heterogeneous enhancement on post contrast imaging (A). Two-year after secondary surgery plus radiotherapy. T1-weighted enhanced magnetic resonance imaging shows no evidence of disease residue or recurrence (B).
case_images: 1477-7819-10-10-3.jpg
case_images: PMC3268097_01_1477-7819-10-10-3.jpg
case_images: F3
case_images: Nine months later, he was re-admitted with facial palsy and left upper limb weakness again, and brain MRI showed local tumor recurrence (Figure 3A). During the more than 2 years follow-up, brain MRI revealed no residual or recurred tumor (Figure 3B).