颅内原发性内胚窦瘤6例临床病理观察

Primary intracranial endodermal sinus tumor: A clinicopathologic analysis of 6 cases

目的 研究颅内原发性内胚窦瘤 (EST)的临床病理特点 ,探讨其组织发生。方法 临床资料分析及运用组织学、组化、免疫组化 (ABC或S P法 )和电镜观察 6例颅内原发性EST及伴有EST的生殖细胞肿瘤。结果 6例EST及伴有EST的生殖细胞肿瘤中 ,男性 5例 ,女性 1例 ,年龄 5～ 16岁 ,平均 10岁 ,临床以颅内高压为主要症状。EST组织学特点 :疏松网状结构、嗜酸性透明小球及基膜样物形成、腺泡状和腺管状结构 ,部分伴有“血管套”结构、多囊性卵黄囊结构。免疫组化 :瘤细胞AFP、CEA和α 1 抗胰蛋白酶 (+)。电镜观察最有特征性的是瘤细胞内外有大量高电子密度圆形物质 ,瘤细胞外可见无定形基底膜样物质。随访的 4例患者 3～ 10个月内死亡 ,1例术后 7年复发。结论 颅内原发性EST及伴有EST的生殖细胞肿瘤多见于男性 ,好发于青少年 ,多位于松果体区、鞍区和第三脑室。颅内原发性EST及伴有EST的生殖细胞肿瘤少见 ,高度恶性 。

Objective To study the clinicopathologic characteristics and histogenesis of endodermal sinus tumor (EST). Methods Histopathologic, immunohistochemical and electron microscopic techniques were used in 6 cases of primary intracranial EST. Results There were 5 male and 1 female, with age ranged from 5 to 16 years (mean 10 ). Main clinical feature was high intracranial pressure. Histologic appearance of the tumor included reticular structure, hyaline droplets, basement membrane like structures, a gland like alveolar pattern with invaginations resembling the glomeruli of the kidney, and yolk sac vesicles. Immunohistochemically, all the cases were positive for AFP, CEA and anti alpha 1 trypsin. Electron microscopic examination showed aggregation of electron dense material in the extracelluar and intracellular spaces and amorphous basement membrane like substance in the extracellular matrix in 4 cases. Follow up results showed that 4 patients died within 10 months, and one had recurrence in 7 years after operation. Conclusions Primary intracranial EST is a distinct clinicopathologic entity in children and adolescent, mostly in male. It is a rare and highly malignant neoplasm of germ cell origin.