促结缔组织增生性小圆细胞肿瘤的临床病理特征分析

Clinicopathological analysis of desmoplastic small round cell tumor

目的:研究促结缔组织增生性小圆细胞肿瘤(desmoplastic small round cell tumor,DSRCT)的临床病理特征。方法:回顾性分析2012年1月至2019年11月7例首都医科大学附属北京世纪坛医院诊断的DSRCT临床资料,复阅病理切片,并行免疫组织化学法及荧光原位杂交法(fluorescence in situ hybridization,FISH)检测,总结病理特征。结果:患者均为男性,中位年龄29岁,部位均为腹腔,临床症状包括腹胀腹痛、腹水、大便习惯改变、排尿困难。病理大体上表现为大网膜或肠系膜多发灰白结节,组织学上表现为大小不一、形态不规则的小圆细胞巢及增生的纤维结缔组织。免疫组织化学法检测显示肿瘤细胞中的Desmin和Vimentin呈核旁点灶状阳性表达,FISH检测EWSR1-WT1融合基因阳性。中位随访期为15个月,6例生存,1例死亡。结论:DSRCT发病率低,高度恶性,Desmin和Vimentin核旁点灶状阳性表达具有提示意义,EWSR1-WT1融合基因阳性具有确诊意义。

Objective:We aimed to investigate the clinicopathological features of desmoplastic small round cell tumor(DSRCT).Methods:We conducted a retrospective analysis of the clinical characteristics of 7 DSRCT specimens collected from January 2012 to November 2019 in Beijing Shijitan Hospital,Capital Medical University.Pathological slides were further studied.Immunohistochemistry and fluorescence in situ hybridization(FISH)were carried out to study the pathological characteristics.Results:The patients were all male with the median age of 29 years.All tumors were located in the abdominal cavity.The clinical symptoms were abdominal distension,abdominal pain,altered bowel habits,and dysuria.Gross pathology showed multiple grey nodules scattered on the omentum and mesentery.Histopathology showed well-defined nests of small round blue tumor cells separated by abundant desmoplastic stroma.Immunohistochemistry showed distinctive expression of paranuclear dot-like pattern of Desmin and Vimentin;expression of EWSR1-WT1 fusion gene was detected by FISH.At the median follow-up period of 15 months,six patients were alive.Conclusions:DSRCT is highly malignant,with distinctive pathological features of paranuclear dot-like expression of Desmin and Vimentin by immunohistochemistry,and the expression of EWSR1-WT1 fusion gene.