易漏诊的甲状腺乳头状癌临床病理观察

Easily missed papillary thyroid carcinoma:a clinicopathologic and review of literature

目的探讨易漏诊的甲状腺乳头状癌(PTC)的临床病理学特征、诊断与鉴别诊断。方法对1例易漏诊的甲状腺乳头状癌进行冷冻切片及常规石蜡切片观察、免疫组化及分子病理检测,结合文献分析其诊断特点及鉴别诊断。结果甲状腺术中冷冻镜下见,甲状腺滤泡上皮部分呈乳头状增生,细胞核稍增大,但不拥挤,未见明显的毛玻璃样核、核沟及核内包涵体,局灶区域偶见少许砂砾体,形态学较温和。术后组织见甲状腺滤泡上皮呈乳头状或实性生长,可见砂砾体,但细胞学仍缺乏乳头状癌的形态特点。多处取材发现肿瘤周围组织侵犯和淋巴结转移。免疫组化:甲状腺内及淋巴结内肿瘤细胞TTF-1、TG、CK19和galectin-3(+),TPO(-)。分子病理示KRAS基因12密码子(34G>C)突变,G12R(Gly12Arg)突变型。结论部分甲状腺乳头状癌缺乏典型细胞学特征,应通过广泛取材和免疫组化确诊。

Objective To investigate the clinicopathological features,diagnosis and differential diagnosis of easily missed papillary thyroid carcinoma. Methods A case of easily missed papillary thyroid carcinoma was analyzed with frozen sections,paraffin section, immunohistochemistry staining and molecular pathology phenotype and its diagnosis and differential diagnosis were explored with review of the literature. Results Thyroid intraoperative frozen microscope showed that thyroid follicular epithelial cells were papillary hyperplasia,the nucleus were slightly increased,but not crowded. No obvious ground glass nuclei,nuclear grooves and intranuclear inclusions were found,and focal area of the neoplasm occasionally saw a little sand body. The morphology of thyroid tumor cells was milder. Postoperative thyroid follicular epithelium grew with papillary or solid, sand bodies were able to be seen, but still lacking cytological morphological characteristics of papillary carcinoma. However,invasion of the surrounding tissue and the metastasis of lymph node in the slides. Immunohistochemistry showed that the tumor cells were TTF-1（ ＋）,TG（ ＋）,CK19（ ＋）,galectin-3（ ＋）,TPO（-）. Molecular pathology showed that codon 12（ 34 G〉 C） of KRAS gene,G12R（ Gly12Arg）.Conclusion Some papillary thyroid carcinomas which lacking typical cytological features should be diagnosed by extensive drawn and immunohistochemistry.