胎儿骶尾部先天性未成熟畸胎瘤尸检1例报道并文献复习

Congenital immature teratoma of fetal sacrococcygeal region: report of a case and review of the literature

目的探讨胎儿骶尾部先天性未成熟畸胎瘤的临床病理特征、诊断及鉴别诊断。方法分析1例胎儿骶尾部先天性未成熟畸胎瘤的临床资料、尸检病理结果,并结合文献复习。结果 B超示胎儿脊柱骶尾部囊、实性混合回声。尸检发现胎儿骶尾部可见5.5 cm×5 cm×4 cm大小肿物,切面呈囊实性,囊内含淡黄色液体。光镜下肿瘤由多个胚层组成,可见角化的鳞状上皮、纤毛上皮、软骨、平滑肌、肠管、内胚窦样结构、神经胶质细胞和原始神经管。免疫组化:小管样结构细胞nestin、vimentin和CD99(+),GFAP、NF和Neu N(-);周围神经胶质细胞GFAP和NF(+),Neu N(-);上皮细胞CK(+),内胚窦样结构S-100(+);Ki-67阳性率为20%,p53(-)。结论胎儿骶尾部先天性未成熟畸胎瘤罕见,确诊依赖于B超、组织学形态和免疫组化结果,需要与成熟性畸胎瘤和原始神经外胚层肿瘤鉴别。

Objective To explore the clinical and pathological features, diagnosis and differential diagnosis of congenital immature teratoma of fetal sacroeoecygeal region. Methods A case of congenital immature teratoma of fetal sacrocoecygeal site was observed by clinical data analysis, histopathology, immunohistochemistry, and some relevant literatures were reviewed： Results B ultrasound showed fetal sacrococcygeal cyst and spinal solid mixed echo. The size of the tumor located in fetal sacrum and coccyx was 5.5 em × 5 cm × 4 cm. Tumor section showed cystic and solid. There was pale yellow liquid in the cyst. Under light microscope, the tumor was composed of a plurality of ectoderm. There were keratinized squamous epithelium, ciliary epithelium, cartilage, muscle, intestine, neuroglia cells and primitive neural tube. The primitive neural tube was positive for nestin, CD99 and vimentin. Neuroglia were positive for GFAP. Nerve fibers were positive for NF. Epithelium was positive for CK. Endodermal sinus-like structure was positive for S-100. Ki-67 index was 20% in focal area. The tumor cells were negative for P53 and NeuN. Conclusion Congenital immature teratoma of fetal sacrococeyx is a rare tumor. Its diagnosis depends on the imaging, histological features and immunohistochemical results. The turnout must be distinguished from mature teratoma and primitive neurotodermal tumour.