上皮样炎性肌纤维母细胞肉瘤1例临床病理观察

Epithelioid inflammatory myofibroblastic sarcoma: a clinicopathologic analysis of one case

目的分析上皮样炎性肌纤维母细胞肉瘤(EIMS)的临床及病理特征,旨在提高对本病的认识及鉴别。方法对1例EIMS进行免疫组化染色,荧光原位杂交检测ALK基因重排,观察其病理特点并复习文献。结果患者女,56岁,腹痛2月余。肿物位于肠系膜,直径约15 cm,切面黏液样外观。镜下见肿瘤富于黏液背景,瘤细胞呈弥漫或团块状分布,细胞呈上皮样,圆形、多边形、短梭形,胞质丰富、核偏位,核分裂活跃,间质内见显著炎细胞浸润。免疫组化显示,ALK(5A4)及ALK(1A4)阳性均特征性定位于肿瘤细胞核膜。FISH检测显示ALK基因重排阳性。此外,该例肿瘤还表达vimentin、Desmin、D2-40、WT-1、CD99。术后约2个月后复发,生存期约5个月。结论EIMS是罕见的一种软组织恶性肿瘤,恶性度极高,临床表现无特异性,诊断主要依赖病理形态学及免疫组化染色。

Objective To present a case report of epithelioid inflammatory myofibroblastic sarcoma(EIMS),aiming to enhance the understanding of its clinicopathological characteristics.Methods Immunohistochemistry was performed on a case of EIMS and FISH was employed to detect ALK fusion.Results A 56-year-old woman suffered stomachache for about 2 months.A mass was discovered in her abdominal cavity,which was approximately 15 cm in diameter and appeared with mucus-like cutting surface.Microscopic evaluation revealed the distribution of tumors cells into myxoid stroma,which were epitheloid,round,polygonal,short-spindle with abundant cytoplasm,vesicular nuclei,prominent nucleoli and a lot of mitosis.In addition,numerous inflammatory cells were observed in background that was predominated by neutrophilic cells.ALK was located on nuclear membrane by immunostaining with ALK(5 A4)and ALK(1 A4),and the gene fusion of ALK was identified by FISH.Moreover,tumor cells showed positive staining against vimentin,desmin,D2-40,WT-1 and CD99.The patient suffered recurrence two months later and survived for about five months.Conclusion EIMS is a soft tissue tumor with high malignancy,and its diagnosis depends on morphological changes and immunostaining.