松果体母细胞瘤一例报告并文献复习

Pineoblastoma:one case report and review of literatures

目的探讨松果体母细胞瘤患者的临床和病理学特征,并复习相关文献。方法与结果一例12岁女性患者,无明显诱因头痛3年。头部MRI检查显示松果体区椭圆形等T_1、等或低T_2信号影,大小约2.70cm×2.00cm,增强扫描呈明显均匀强化。手术中可见肿瘤组织呈暗红色,边界尚清楚,有出血灶,分块切除肿瘤组织和包膜后第三脑室和侧脑室脑脊液通畅流出。光学显微镜观察肿瘤细胞呈弥散或片状密集排列,组织发生大片凝固性坏死;肿瘤细胞形态较小,细胞核呈圆形或不规则形,核深染、异型性明显、分裂象多见,细胞质极少、边界欠清晰;部分区域肿瘤细胞可见微小钙化灶、Homer-Wright菊形团结构和不典型的Flexner-Weinsteiner菊形团结构。免疫组织化学染色肿瘤细胞突触素、嗜铬素A表达阳性;胶质纤维酸性蛋白、神经元核抗原表达阴性;Ki-67抗原标记指数约20%。手术后随访6个月,肿瘤无复发。结论松果体母细胞瘤是临床少见的发生于松果体实质的幼稚分化肿瘤,以20岁以下青年人高发,呈高度恶性,患者预后不良。

Objective To report a rare case of pineoblastoma and to explore the clinical and pathological features of pineoblastoma. Methods Retrospectively analysed the clinical presentation, histopathologieal and immunohistochemical features of one case with pineoblastoma. The related literatures were reviewed. Results A 12-year-old female patient presented with headache for 3 years. Magnetic resonance imaging （MRI） showed that ovoid nodule was found to be located at the pineal region with clear margin, measuring 2.70 cm × 2.00 cm in dimension. T1WI showed the isointense comparable to the grey mater in the lesion. T2WI showed the hypointense or isointense, and homogeneous enhancement was observed. During operatxon, tumor tissue was in dark-red color, with well demarcated margin. The tumor nodule was resected segmentally. After resection of the tumor tissue and capsule, cerebrospinal fluid unobstruetedly Honed out from the third and lateral ventricles. Foci of hemorrhage was also seen. Grossly, grayish tissue fragments were submitted, measuring 1.50 cm × 1.00 cm × 0.50 cm. Histomorphologically, neoplastic cells were diffusely with high cellularity with sheet-hke necrotic foci and no lobular structure was observed. Micro-calcification, Homer-Wright rosettes and Flexner-Weinstemer rosettes were occasionally identified. Small tumor cells were darkly stained with scant cytoplasm and prominent atypia. Mitosis were easily seen. Immuohistochemistry showed that synapsin （Syn）, chromogranin A （CgA） were positive, the Ki-67 labeling index was 20% in tumor cells. However, glial fibrillary acidic protein （GFAP） and neuronal nuclear antigen （Neu-N） were negative. After operation, the patient was followed for 6 months, and no recurrence occurred. Conclusion Pineoblastoma represents a very rare primitive tumor in the pineal region. It usually occurs in the first 2 decades of life with poor prognosis and high-grade malignancy,