Stomatin‐like protein 2 overexpression in papillary thyroid carcinoma is significantly associated with high‐risk clinicopathological parameters and BRAFV600E mutation

Stomatin‐like protein 2 (SLP‐2), a member of the stomatin protein family, has emerged as a potential molecular hallmark of tumor progression in several human malignancies. The aim of this study was to analyze SLP‐2 expression pattern in benign and malignant thyroid tumors (n = 210) and to examine its relationship with clinicopathological parameters and BRAFV600E mutation in thyroid cancer. SLP‐2 immunohistochemical expression was not detected in benign adenomas and was absent/weak in follicular and anaplastic carcinomas. High expression levels of SLP‐2, found only in papillary thyroid carcinoma (PTC), particularly in the classical variant, were significantly associated with adverse clinicopathological parameters: lymph node metastasis (p = 0.002), extrathyroid invasion (p < 0.001), pT status (p < 0.001), and advanced tumor stage (p = 0.001). Additional genotyping of PTC cases for the BRAFV600E mutation revealed for the first time a close relation between SLP‐2 overexpression and the presence of BRAF mutation (p = 0.02) with high positive rates of lymph node metastasis (70%) and extrathyroid invasion (80%) in these cases. The significant association of SLP‐2 overexpression with unfavorable clinicopathological characteristics and BRAFV600E mutation indicates that SLP‐2 may have a role in aggressiveness of BRAF‐mutated PTC and that SLP‐2 evaluation could be clinically useful in identification of high‐risk PTC patients.     

Immunohistochemistry is highly sensitive and specific for detecting the BRAF V600E mutation in papillary thyroid carcinoma

The V600E mutation in the B-type Raf kinase (BRAF) gene is a common genetic change in cases of papillary thyroid carcinoma (PTC) that appears to play a key role in the development and progression of this disease. We sought to assess the sensitivity and specificity of immunohistochemical detection of this mutation with a V600E mutated BRAF antibody in a Chinese PTC cohort. In this study, we used fully automated immunohistochemistry (IHC) assay with a BRAF V600E (VE1) mouse monoclonal primary antibody to screen for the BRAF V600E mutation in 556 cases of PTC. Moreover, to verify the IHC staining results, real-time PCR was applied to detect this mutation in the same patient cohort. Among the 556 cases in the examined primary PTC cohort, 414 (74.5%) cases and 419 (75.4%) cases were positive for the BRAF V600E mutation by IHC staining and by real-time PCR, respectively. The real-time PCR results indicated that the sensitivity and specificity of IHC staining for the BRAF V600E mutation were 98.8% and 100%, respectively. The BRAF V600E mutation was common among Chinese patients with primary PTC, and was strongly correlated with older patient age and the conventional subtype of PTC but was not associated with parameters of clinicopathological aggressiveness. The fully automated IHC is a reliable technique that can serve as an alternative to molecular biological approaches for the routine detection of the BRAF V600E mutation in PTC patients.     

分化型甲状腺癌中BRAF V600E突变分析

目的探讨分化型甲状腺癌中BRAF V600E突变与临床病理特征的关系。方法收集甲状腺乳头状癌(papillary thyroid carcinoma,PTC)80例(其中经典型67例、滤泡亚型8例、嗜酸细胞亚型3例、高细胞亚型2例)、滤泡癌5例,其中30例PTC取相应癌旁组织,全部送基因检测室检测BRAF V600E突变情况。结果 80例PTC中BRAF V600E突变率为65.0%,5例滤泡癌及30例癌旁组织中未发现BRAF V600E突变;BRAF V600E突变与患者年龄、肿瘤包膜侵犯、淋巴结转移及TNM分期有关。PTC亚型中,经典型和高细胞亚型的BRAF V600E突变率较高(70.1%、100.0%),滤泡亚型的突变率较低(33.3%)。结论PTC中BRAF V600E突变可能与患者年龄有一定相关性,还与包膜侵犯、淋巴结转移及TNM分期有关,经典型和高细胞亚型的BRAF V600E突变率较高,明显高于滤泡亚型。     

Investigation of BRAF V600E detection approaches in papillary thyroid carcinoma

Objective

The detection of BRAF V600E mutation in papillary thyroid carcinoma (PTC) may be helpful to offer diagnostic confirmation. Additionally, such detection may provide a targeted therapeutic approach for the radioactive iodine resistant patients to predict adverse outcomes. To compare the results of immunohistochemistry (IHC) method using the anti-BRAF V600E (VE1) antibody with the Quantitative real-time polymerase chain reaction (qPCR) approach in examining BRAF V600E mutation in PTC, we investigated the sensitivity and specificity of BRAF V600E (clone VE1) mouse monoclonal antibody in detecting the BRAF V600E mutation and correlated BRAF V600E mutation with clinicopathologic features in PTC.

新疆地区甲状腺乳头状癌中BRAF V600E基因的表达及意义

目的探讨新疆地区BRAF V600E基因点突变在甲状腺乳头状癌(papillary thyroid carcinoma,PTC)中的表达,及其与临床病理特征的关系。方法收集原发性PTC 178例,石蜡包埋组织经QIAGEN试剂盒提取DNA,经Taq Man探针荧光定量PCR技术检测PTC中BRAF基因点突变。结果 178例原发性PTC中BRAF V600E基因点突变142例,突变率为79.8%(142/178)。患者年龄(≥45岁)、肿瘤直径(≤1 cm)、被膜外侵犯BRAF V600E基因点突变率高(P均0.05),而BRAF V600E基因点突变与患者性别、多灶性及淋巴结转移灶和肿瘤部位均无相关性(P均0.05)。结论新疆地区PTC中BRAF V600E基因点突变与临床病理特征密切相关,且具有一定特异性,可作为PTC诊断提供依据。     

甲状腺乳头状癌中TROP-2表达的临床意义及其诊断价值

目的观察人类滋养层细胞表面抗原2(TROP-2)在甲状腺乳头状癌(papillary thyroid carcinoma,PTC)中的表达,探讨TROP-2在PTC中表达的临床意义及其诊断价值。方法采用免疫组化EnVision法检测100例甲状腺恶性病变(PTC 75例、滤泡性癌10例、髓样癌10例、差分化癌5例)、45例良性病变(正常甲状腺10例、结节性甲状腺肿10例、桥本甲状腺炎15例、滤泡性腺瘤10例),5例具有乳头样核特征的非浸润性甲状腺滤泡性肿瘤(non-invasive folliculaRthyroid neoplasms with papillary-like nucleaRfeatures,NIFTP)中TROP-2的表达;ARMS法检测PTC中BRAF V600E基因突变。分析TROP-2对PTC诊断的敏感性和特异性,及其与PTC临床病理特征以及BRAF V600E基因突变的关系。结果TROP-2在PTC中的阳性率为81.3%(61/75),在其他甲状腺恶性肿瘤和良性病变中均阴性,TROP-2对PTC诊断的敏感性为81.3%,特异性为100%。TROP-2表达与PTC淋巴结转移有关(P<0.05),与患者年龄、性别、肿瘤部位及临床分期无关(P>0.05),经典型PTC中TROP-2表达高于滤泡亚型PTC(P<0.05)。PTC中TROP-2表达与BRAF V600E基因突变呈正相关(P<0.05)。结论TROP-2是一种具有高度特异性和敏感性的诊断PTC的标志物,TROP-2检测可预测PTC的临床生物学行为和BRAF V600E基因突变状态,并对于形态学变形的PTC、微小型PTC和PTC的甲状腺内扩散的诊断和识别具有重要价值。     

Detection of BRAFV600E mutation on papillary thyroid carcinoma and metastatic malignant melanoma by fine‐needle aspiration cytology

A genetic link between cutaneous melanoma and thyroid cancer (TC) has been identified. A high percentage of both melanomas and papillary carcinomas of the thyroid harbors a recurrent mutation (i.e., BRAF^V600E) in the BRAF oncogene. Herein, we report the case of a 65‐year‐old man with papillary TC and cutaneous malignant melanoma metastatic to masseter muscle, both characterized by BRAF mutation. This is one of the rare reports in which a complete molecular characterization has been performed. As the patients with papillary thyroid carcinoma have a higher risk of malignant melanoma and vice versa, continuous monitoring of such patients, with either of these tumors is necessary. Fine‐needle aspiration cytology is useful as shown in the present case. Diagn. Cytopathol. 2014;42:877–879. © Wiley Periodicals, Inc.     

实时剪切波弹性成像杨氏模量最大值诊断甲状腺乳头状癌BRAF V600E基因突变的价值

目的:探究实时剪切波弹性成像（SWE）杨氏模量最大值诊断甲状腺乳头状癌（PTC）鼠类肉瘤滤过性毒菌致癌同源体B1（BRAF）V600E基因突变的价值。方法:回顾性分析2018年1月~2019年6月宿迁市第一人民医院收治的110例PTC患者共124个结节的临床及超声影像学资料。患者经病理学检查均确诊为PTC,并完成了BRAF V600E基因检测以及SWE检查,临床资料完整。通过比较V600E基因突变型与野生型PTC的SWE检查结果,并绘制患者Emax值的ROC曲线,分析Emax值对PTC患者BRAF V600E基因突变的诊断效能。结果:BRAF基因检测结果显示:124个PTC结节BRAF基因检测V600E野生型共37个,V600E突变型共87个。野生型PTC结节的SWE图像多以蓝色为主,而突变型主要表现为红橙相间彩色混杂的图像。突变组PTC结节Emax、Emean、Eratio值均明显大于野生组,比较差异具有统计学意义（P<0.05）,ROC曲线分析显示:Emax值诊断V600E突变的AUC=0.846>0.5（95%CI:0.808~0.885, P<0.01）;Cut-off值为43.65 kPa,此时敏感度为91.45%,特异性为68.23%。以Emax≥43.65 kPa为临界值对124个结节进行诊断,结果显示:SWE诊断PTC结节为V600E基因突变型90个,野生型34个,正确率为86.29%;SWE诊断结果与基因检测结果一致性显著（Kappa值=0.665, P<0.01）。结论:PTC BRAF V600E基因突变型与野生型的SWE影像学特征具有明显差异,应用SWE的Emax值诊断PTC结节V600E基因突变的正确率和敏感性均较高,诊断价值显著,值得在临床上推广应用。     

A valuable adjunct to FNA diagnosis of papillary thyroid carcinoma: In‐house PCR assay for BRAF T1799A (V600E)

The diagnostic approach to thyroid nodules generally starts with FNA cytology. However, approximately one‐fifth of cytologic evaluations yield indeterminate cytological findings but only 20% of cases with indeterminate thyroid nodule cytology have a cancer diagnosis, emphasizing the need for an effective ancillary test based on FNA material to help prevent unnecessary surgery. Detection of BRAFV600E mutation, the genetic signature of papillary thyroid carcinoma (PTC) in FNA material provides an invaluable diagnostic adjunct to overcome the limitations of FNA cytology. There are many ways to detect V600E, such as direct DNA sequencing, allele‐specific PCR and hybridization‐based colorimetric methods. In this study, a newer simple PCR method is presented that removes requirements for sequencing special equipment and commercial kits. Two forward primers including the mutant sequence specific (F2), and one common reverse (R) primer were optimized to generate a 241 bp fragment (F1R), an internal PCR control, and a 141 bp fragment (F2R) denoting the presence of V600E. Sensitivity studies revealed that the assay is capable of detecting V600E even in 1 ng of DNA. Direct sequencing data of 241 bp F1R fragment proved the specificity of the assay. For validation studies of the sequence specific multiplex PCR assay, archival FNA slides were used in a group of thyroid lesions including PTC, follicular carcinoma, follicular adenoma, Hashimoto thyroiditis, and benign thyroid nodules. The newer PCR‐based method presented in this study is a practical, inexpensive one‐step assay to detect the BRAF T1796A mutation on FNA samples. Diagn. Cytopathol. 2011;39:424–427. © 2010 Wiley‐Liss, Inc.     

BRAF基因突变在甲状腺乳头状癌中的临床意义

目的：探讨BRAF V600E基因突变与甲状腺乳头状癌的临床相关性。方法：采用PCR技术和直接测序法,对63例甲状腺乳头状癌患者和45例其他类型甲状腺疾病患者石蜡组织BRAF V600E基因突变进行检测。结果：甲状腺乳头状癌组中32例存在突变;而在其他类型甲状腺疾病组中未发现突变。BRAF V600E基因突变在甲状腺乳头状癌不同肿瘤直径组之间的比较差异以及在有无区域淋巴结转移组之间的比较差异均具有统计学意义(P<0.05)。结论：BRAF V600E基因突变与甲状腺乳头状癌的发生、肿瘤的大小和区域淋巴结的转移有关。     

Overexpression of cytokeratin 17 is associated with the development of papillary thyroid carcinoma and the presence of lymph node metastasis

Cytokeratin 17 (CK17), a basal/myoepithelial cell keratin, appears to play an important role in the progression of several human malignancies. Increased CK17 expression has previously described in cases of papillary thyroid carcinoma (PTC). However, no studies to date have investigated the clinical significance of CK17 expression in patients with PTC. The aim of this study was to compare the expression of CK17 in patients with PTC with that observed in normal thyroid tissue and benign thyroid lesions, and to examine the relationship between CK17 expression and clinicopathologic characteristics of patients with PTC. CK17 protein expression was evaluated by immunohistochemistry on tissue microarrays containing thyroid tissue samples from 108 PTCs, 16 nodular goiters, and 81 healthy controls. Sixty-five of the 108 (60.2%) PTC tissue samples exhibited positive CK17 expression, whereas all nodular goiters and normal thyroid tissue samples showed a complete absence of CK17 immunoreactivity. The difference in frequency of CK17 positivity between PTC (65/108, 60.2%), normal thyroid tissue (0/81, 0.0%), and benign thyroid lesions (0/16, 0.0%) was statistically significant (P<0.001). Positive CK17 expression in PTC was significantly associated with the presence of lymph node metastasis (P=0.024) and higher pN stage (P=0.028). Expression of CK17 is significantly increased in cases of PTC compared to normal tissue and benign thyroid lesions, and CK17 overexpression is associated with the presence of lymph node metastasis in patients with PTC. These findings suggest that CK17 is involved in the development and metastasis of PTC.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

Clinical significance of RET/PTC and p53 protein expression in sporadic papillary thyroid carcinoma

AIMS: Rearranged during Transfection (RET)/papillary thyroid carcinoma (PTC) and p53 are two genes involved in the pathogenesis of PTC. It has been suggested that RET/PTC expression is associated with higher rates of local extension and lymph node involvement, whereas p53 mutations are more frequent in poorly differentiated and anaplastic carcinomas. In addition, experimental studies have shown that p53 activity can modify the behaviour of PTC carrying RET/PTC. The aim of this study was to investigate the expression of both RET/PTC and p53 in order to evaluate their usefulness as prognostic factors. METHODS AND RESULTS: Resected specimens of 61 cases of PTC were studied immunohistochemically using a polyclonal antibody to RET and a monoclonal antibody to p53 protein. RET/PTC expression was associated with extrathyroid extension of PTC, at diagnosis (P < 0.05). In contrast, no relationship between p53 immunoreactivity and clinical status was found. In addition, p53 expression was more prevalent among RET/PTC+ patients, and significantly influenced the relationship observed between RET/PTC and extrathyroid extension of the disease. CONCLUSION: Our results suggest that immunohistochemistry for both PTC/RET and p53 could be useful in the clinical evaluation of patients with PTC.     

Occult oncocytic papillary thyroid carcinoma with lymphoid stroma (Warthin-like tumor): report of a case with concomitant mutations of BRAF V600E and V600K

Warthin-Like tumor of the thyroid is a recently described rare variant of papillary thyroid cancer. The distinct histological feature of this variant is papillary architecture lining oncocytic epithelial cells with nuclear characteristics of papillary carcinoma, accompanied by prominent lymphocytic infiltration in the papillary stalks. Here, we present a case of occult Warthin-like papillary thyroid carcinoma, 0.5-cm in maximum dimension, underwent left thyroid lobectomy in a 65 years old Chinese woman. In this case, there was no extrathyroid extension, vascular invasion and lymphatic metastasis, as well as no complication of lymphocytic thyroiditis. Immunohistochemistry staining revealed that the tumor cells were positive for Leu-M1, HBME-1, 34βE12, and MIB-1 labeling index was low. RET/PTC expression was absent in tumor cells. Furthermore, activated point mutations of BRAF V600E and V600K were concurrently detected by DNA sequencing. Further studies are needed to elucidate the prevalence and role of BRAF^V600K mutation in papillary thyroid carcinoma, and long-term follow-up for the patient is needed to clarify the biological behavior of this variant with dual BRAF mutations.     

An immunohistochemical and genetic study of BRAFV600E mutation in Japanese patients with ameloblastoma

Ameloblastoma is an odontogenic tumor of the jaw. It most frequently occurs in the mandible, and less often in the maxilla. Mandibular ameloblastoma harbors a BRAF mutation that causes a valine (V) to glutamic acid (E) substitution at codon 600 (BRAF^V600E). We examined specimens from 32 Japanese patients to detect the prevalence of the BRAF^V600E mutation, and to evaluate the relationship between immunohistochemical (IHC) expression and genetic results, of BRAF^V600E+ ameloblastoma. Among the 32 cases, 22 (69%) were IHC positive for BRAF^V600E protein, and 10 (31%) were IHC negative; and polymerase chain reaction showed 16 of 21 tested cases (76%) carried the BRAF^V600E mutation. Our findings indicate that that samples that stain IHC positive for BRAF^V600E protein are more likely to carry the BRAF^V600E mutation. These results support assessments for BRAF mutations, and the use of BRAF inhibitors as targeted therapy for ameloblastoma in Japanese patients.