甲状腺微小乳头状癌术中冰冻未能明确诊断的原因分析

Reason Analysis of Frozen Sections Not Diagnosis on Hyroidpapillary Microcarcinoma

目的对甲状腺微小乳头状癌(PTMC)术中冰冻病理未能明确诊断的原因进行分析,分析延迟诊断和假阴性诊断的陷阱。方法对术中未能诊断的8例PTMC的冰冻切片和石蜡切片进行对比观察,免疫组化法检测半乳糖凝集素-3(Galectin-3)、间皮瘤相关抗体-1(HBME-1)、细胞角蛋白19(CK19)的表达。结果8例PTMC,术中冰冻均未确诊,延迟诊断4例,假阴性2例,冰冻取材阴性2例,其中1例肿瘤(钙化明显)直径为8 mm,2例肿瘤直径为6 mm,其余均<3 mm。以上病例中5例经石蜡切片和免疫组化染色证实,出现CK19、HBME-1、Galectin-3三者联合弥漫中强阳性表达,另3例由于病灶较小,免疫组化切片时病灶消失。结论冰冻切片未见乳头的PTMC是诊断的主要陷阱,钙化明显、淋巴细胞较多时常掩盖细胞核的形态,加之病灶太小、经验不足和冰冻切片的人工假象,对于肿瘤的浸润性边界、间质硬化、异型性、核沟、核内包涵体的判断有误,从而导致冰冻未能明确诊断。

Objective To analysis the reason of frozen sections not diagnosis on hyroidpapillary microcarcinoma(PTMC)and thepitfall in delayed diagnosis and false-negative diagnosis of PTMC.Methods To 8 PTMC cases frozen sections not diagnosis,control observation was made on frozen sections and paraffin sections.Immunohistochemical stains for CK19,HBME-1 and Galectin-3 were performed.Results In 8 PTMC cases frozen sections,they were not diagnosed.There were frozen section delayed(4 cases)and frozen section false-negative(2 cases)and frozen section negative(2 cases).The diameter of PTMC was 8 mm in 1 case which had obvious calcification.The diameter of PTMC was 6 mm in 2 case.The others was not more than 3 mm.The immunohistochemical staining of CK19,HBME-1 and Galectin-3 showed moderate to strong positive co-expressions of the three molecules in 5 case.Because the diameter of PTMC was too small.The nidus was disappeared immunohistochemical staining.Conclusion PTMC no papilla in frozen sections is the pitfall in pathological diagnosis.Obvious calcification and multiple lymphocyte often cover up characteristics of nucleus.Because the lesion is too small the experience was inadequate,artificial illusion is obvious in frozen section,and wrong judgment to infiltration boundary,interstitial hardening,atypia,nuclear groove,intranuclear pseudoinclusion.The frozen section could not be definitely diagnosed.