14例胰腺实性假乳头状肿瘤的临床病理分析

Clinical pathological analysis in 14 cases of pancreatic solid-pseudopapillary tumors

目的:探讨胰腺实性假乳头状肿瘤(solid-pseudopapillary tumor,SPPT)的临床病理学特征以及可用于鉴别诊断的免疫组织化学新方法。方法:对14例SPPT患者的临床特征、组织学形态及其嗜铬素(CgA)、突触素(Syn)、E-钙粘素(E-cadherin)、β-连环蛋白(β-catenin)和细胞周期蛋白D1(Cyclin D1)的免疫组织化学结果进行观察,并与5例胰腺高分化内分泌肿瘤和高分化内分泌癌(WET/WEC)的结果进行比较。结果:SPPT主要发生于年轻女性,胰头多见,肿瘤呈囊实性,虽边界清楚,但常可见局灶的浸润现象。SPPT在组织学形态上与WET/WEC,特别是实性型的WET/WEC有一定的相似性,二者CgA、Syn均可阳性,但SPPT的E-cadherin染色呈现100%的膜阴性,甚至可出现核阳性信号(5/14),而WET/WEC保留膜阳性信号,核均为阴性。SPPT的β-catenin染色均呈现胞核及胞浆阳性,而WET/WEC均呈现胞膜及胞浆阳性,甚至出现核旁的点状阳性信号,而细胞核始终为阴性,类似于胰岛细胞的染色模式。SPPT的Cyclin D1核染色阳性率多大于70%(12/14),而WET/WEC的Cyclin D1染色阳性率均未超过30%。结论:通过对患者临床资料以及包括E-cadherin、β-catenin、Cyclin D1在内的免疫组织化学染色结果的综合分析,有利于SPPT的确诊以及与WET/WEC的鉴别。

Objective：To observe clinical and pathological features of pancreatic solid-pseudopapillary tumor（SPPT）,and to find some useful immunohistochemical methods for its differential diagnosis.Methods： The clinical features of 14 SPPT patients were obtained.Each case underwent microscopic observation and immunohistochemical staining.The primary antibodies were CgA,Syn,E-cadherin,β-catenin and Cyclin D1.These results were compared with 5 pancreatic well-differentiated tumors and well-differentiated carcinomas（WET/WEC）.Results： SPPT mainly involved young women,and the head of pancreas was the commonest location.Tumors were always in solid and cystic gross appearance.Although the tumor＇s borderlines seemed clear,focal infiltrations could often be identified.The histological features of SPPT were similar in some aspects to those of WET/WEC,especially the solid pattern of WET/WEC.Both of them could express CgA and Syn.But all SPPTs lost E-cadherin membranous signals,and even had some nuclear signals（5/14）,while all WET/WECs remained the same staining pattern with normal pancreas cells.β-catenin positive signals in SPPTs were located both in nuclei and plasmas.WET/WECs＇ positive signals were all in membranes and plasmas,but negative ones in nuclei.Perinuclear dot-like signals could also be seen in the majority cells,which were similar to normal islet cells＇ staining pattern.SPPTs＇ nuclear positive rates of Cyclin D1 were usually more than 70%（12/14）.WET/WECs＇ rates were all lower than 30%.Conclusion： Comprehensive analysis of patients＇ clinical,pathological features and immunohistochemistry results,including E-cadherin,β-catenin and Cyclin D1,was helpful to the diagnosis of SPPT and its differential diagnosis of WET/WEC.