Clinicopathological features of cerebellar lipidized medulloblastoma: a case report and review of literatures

摘要

Objective To explore the clinicopathological features of cerebellar lipidized medulloblastoma. Methods The clinical manifestations， neuroimaging, histopathological and immunohistochemical features were analysed in one case of lipidized medulloblastoma in the cerebellar vermis. Related literatures were reviewed. Results A 26 ? year ? old man presented with intermittent headache，accompanied by dizziness, nausea and vomiting. The magnetic resonance imaging (MRI) demonstrated a mass located the cerebellar vermis convex to the fourth ventricle. The tumor with well? demarcated boundary was homogeneous hypointense on T1 weighted and heterogeneous hyperintense on T2 weighted images, and enhanced brilliantly and homogenously on contrast. The patient subsequently underwent gross total mass resection. Microscopically，there was diffuse infiltration by high cellularity of tumor cells. The cytoplasm were thin eosinophilic to amphophilic. The neoplastic cells showed round to oval hyperchromatic nuclei with a delicately stippled chromatin and occasional conspicuous nucleoli and numerous mitotic figures were also present. Thin?wall vascular proliferation was detected. Lipid?laden cells were focally distributed in tumor tissue. On immunohistochemical examination, the neoplasm was reactive for CD56 and synaptophysin (Syn), focally positive for neurofilament protein (NF), weakly positive for oligodendrocyte lineage transcription factor 2 (Olig?2), and negtive for nestin, neuronal nuclei (NeuN), S?100 protein (S ? 100), glial fibrillary acidic protein (GFAP) and epithelial membrane antigen (EMA). TP53 protein was over expressed in 10% of tumor cells. Ki ? 67 antigen labeling index were about 40% . Conclusion Cerebellar lipidized medulloblastoma is rare. Neuroimaging showed space occupying lesion in cerebellar vermis. Histologically, the tumor cells were consisted of monotonous, round cells with focal accumulations of lipidized cells. The differential diagnosis include liponeurocytoma and ependymoma and so on. DOI：10.3969/j.issn.1672?6731.2012.03.014.