摘要目的 研究内皮细胞间紧密连接蛋白Claudin-5和细胞间黏附分子CD99在鉴别胰腺实性-假乳头状瘤(SPN)与胰腺神经内分泌性肿瘤(P-NET)中的意义.方法 应用免疫组织化学MaxVision法检测于2003至2012年收集的37例SPN、21例P-NET组织中Claudin-5和CD99的表达情况.结果 37例SPN,Claudin-5在细胞膜表达,阳性率为100％；21例P-NET,Claudin-5均不表达；两者之间差异有统计学意义(P＜0.01).CD99在SPN和P-NET中的表达模式不同,前者呈核旁点状聚集,后者在细胞膜表达,其表达率分别为91.9％(34/37)和61.9％(13/21)；两者之间差异有统计学意义(P＜0.01).Claudin-5和CD99在SPN中的表达呈显著正相关(r=0.421,P=0.001).结论 对于大体和镜下特征与P-NET相似的SPN病例,仅依靠形态学诊断十分困难.免疫组织化学联合检测Claudin-5和CD99则对鉴别诊断有重要意义.

abstractsObjective To investigate the expression of endothelium tight junction protein Claudin-5 and intercellular adhesion molecule CD99 in solid-pseudopapillary neoplasms (SPN) and neuroendocrine tumors of pancreas (P-NET),and their significance in the differential diagnoses.Methods Immunohistochemical staining of Claudin-5 and CD99 was performed in 37 cases SPN and 21 cases of P-NET.Results Membranous Claudin-5 expression was observed in all cases of SPN but was absent in all cases of P-NET.The difference was significant (P ＜ 0.01).In SPN,91.9％ (34/37) of the cases displayed paranuclear dot-like immunoreactivity for CD99; in contrast,61.9％ (13/21) of the cases of P-NET displayed membranous staining (P ＜ 0.01).There was a positive association between the expression of Claudin-5 and CD99 in SPN (r =0.421,P =O.001).Conclusions Although the macroscopic and microscopic features of SPN are quite characteristic,they may not allow confident differentiation from P-NET in all cases,especially when these characteristics are not classical.If necessary,immunostaining for Claudin-5 and CD99 can help to differentiate between these entities.