分子生物学法分析青少年甲状腺肿物临床病理及特点

探讨青少年甲状腺肿物的临床病理学特点,甲状腺癌的复发、转移和结节性甲状腺肿复发的可能相关因素。按WHO病理分型标准和国际抗癌联盟(UICC)TNM分期标准回顾性分析青少年甲状腺肿物124例及其中部分甲状腺癌和结节性甲状腺肿的随访资料。124例甲状腺肿物患者男女比例约为1 3,甲状腺癌39例(31.5%),其中乳头状癌35例,滤泡癌3例,髓样癌1例;甲状腺腺瘤59例(47.6%),结节性甲状腺肿11例(8.9%),结节性甲状腺肿伴腺瘤7例(5.6%),甲状腺炎5例(4%),甲状舌管囊肿3例(2.4%)。本组资料显示,青少年甲状腺癌以乳头状癌为主,其复发、转移与组织学亚型为弥漫硬化型及甲状腺包膜和其外软组织受侵状态相关。虽然常见淋巴结转移、肺转移以及局部侵犯周围软组织,但患者总体预后较好。结节性甲状腺肿的复发与病变弥漫位于双叶有关,而与患者性别、年龄和是否伴有乳头样及腺瘤样增生关系不密切。     

颈淋巴结转移率在53例甲状腺包裹型乳头状癌相关病理因素分析

目的 探讨甲状腺包裹型乳头状癌的临床病理特征、淋巴结转移率及转移相关因素、治疗及预后。方法 收集武汉大学人民医院病理科2015年9月至2018年12月53例甲状腺包裹型乳头状癌手术切除标本进行回顾性分析。结果 53例甲状腺包裹型乳头状癌患者年龄20～73岁(平均44.2岁),男女比例为1:2.5,肿瘤直径0.1～3.2cm,肿瘤单侧好发,颈淋巴结转移率为13.2%,其中普通型乳头状癌颈淋巴结转移率明显高于乳头状微小癌(P0.05),随访期间预后存活率100%。结论 甲状腺包裹型乳头状癌是甲状腺乳头状癌的一种特殊亚型,颈淋巴结转移率与肿瘤大小密切相关,治疗以手术切除为主,预后相对较好。     

甲状腺乳头状癌淋巴结转移的临床危险因素分析

目的:探讨甲状腺乳头状癌发生颈部淋巴结转移的危险因素。方法:回顾性分析我院自2017年1月至2017年5月手术治疗甲状腺乳头状癌病人177例的临床资料,采用卡方检验、t检验及logistic回归分析甲状腺乳头状癌发生颈部淋巴结的危险因素。结果:甲状腺乳头状癌淋巴结转移率为45.8%,术后并发症发生率为6.2%,淋巴结转移组较未转移组年龄更小、癌结节更大(P0.05),两组比较性别无统计学差异(P0.05),0.5 cm癌结节≤1 cm组较癌结节≤0.5 cm组更易出现淋巴结转移(P0.05),年龄大于45岁、癌结节≤0.5 cm的患者,9.6%发生淋巴结转移。Logistic回归分析提示年龄、癌结节大小是淋巴结转移的独立危险因素(P0.05)。结论:年龄、癌结节大小是淋巴结转移的独立危险因素,年龄越小、癌结节越大的甲状腺乳头状癌患者,越容易出现颈部淋巴结转移。     

女性甲状腺癌的病理与预后分析

目的:探讨女性甲状腺癌的病理特点以及预后影响因素。方法:收集2005年1月至2009年8月,齐齐哈尔和平医院收治的女性甲状腺癌患者148例,回顾分析其临床病理特点以及预后影响因素。结果:病理检查显示131例(88.5%)甲状腺乳头状癌(PTC),6例(4.1%)为滤泡状癌(FTC),3例(2.0%)为髓样癌(MTC),6例(4.1%)为未分化癌(ATC);病理分期Ⅰ-Ⅱ期占45.3%,Ⅲ-Ⅳ期占54.7%;27例(18.24%)为周围组织侵犯,9例(6.1%)为远处转移,10例(6.76%)对侧甲状腺转移,56例(37.84%)颈部淋巴结转移;1年、3年、5年生存率依次为97.3%、93.2%、83.8%;年龄、病理床分期、病理类型、淋巴结转移、远处转移以及周围组织侵犯均是影响临床预后的重要因素(P0.05)。结论:女性甲状腺癌存在病理分期晚、病理分型差、淋巴结转移、远处转移及局部侵犯率高等不良预后因素,早期影像学检查对临床治疗具有指导意义。     

抑癌基因PTEN 在甲状腺乳头状癌中的表达及临床意义*

目的:通过免疫组织化学方法检测PTEN基因在正常甲状腺组织、甲状腺良性肿瘤组织、甲状腺乳头状癌癌组织中的表达水平并进行比较,探讨其对甲状腺乳头状癌诊断和治疗的意义。方法:采用SP免疫组化方法,用已知阳性组织做阳性对照,以磷酸盐缓冲液(PBS)代替一抗做阴性对照,分别作HE染色和免疫组织化学染色。结果:PTEN蛋白在三组组织中的表达差异具有显著性(P<0.001);正常甲状腺组织、甲状腺良性肿瘤组织中的阳性率分别为100%和82.5%,均显著高于甲状腺癌组织中的45%(P<0.05),即PTEN在甲状腺癌中表达显著降低;PTEN在甲状腺乳头状癌淋巴结转移组和无淋巴结转移组阳性表达率分别为15%和60%,差异有显著性(x2=10.91,P=0.001);PTEN在甲状腺乳头状癌在包膜侵犯组和无侵犯组的阳性表达率分别为25.93%和60.61%,差异有显著性(x2=7.22,P=0.007);PTEN在甲状腺癌淋巴结转移组和包膜侵犯组的阳性表达强度显著低于无淋巴结转移和包膜侵犯组(P<0.01),有统计学意义。结论:PTEN基因表达的降低在甲状腺癌的发生和转移过程中起重要作用。     

血清甲状腺过氧化物酶抗体对合并桥本甲状腺炎甲状腺微小癌淋巴结转移影响

目的:探讨合并桥本甲状腺炎的甲状腺微小乳头状癌淋巴结转移的特点,分析血清甲状腺过氧化物酶抗体(Thyroid peroxidase-antibody,TPO-Ab)滴度对该组病例淋巴结转移的影响。方法:回顾性分析武汉同济医院甲状腺乳腺外科2012年1月至2014年5月收治的甲状腺微小癌伴桥本甲状腺炎的病例,运用卡方检验、阈值效应分析、多因素logistic回归方法分析该组病例血清TPO-Ab滴度对淋巴结转移的影响。结果:共收集75例合并桥本甲状腺炎的微小乳头状癌病例,血清TPO-Ab滴度与淋巴结转移相关:抗体滴度对淋巴结转移的影响存在分段特征,有阈值效应,该组病例以212 IU/m L为阈值;多因素logistic回归显示,随着血清TPO-Ab水平升高,淋巴结转移率下降(OR=0.993,95%CL=0.987,0.999,P=0.018)。结论:合并桥本甲状腺炎的甲状腺微小乳头状癌病例,血清TPO-Ab滴度对淋巴结转移的影响可能存在阈值效应,值得深入分析;且高血清TPO-Ab滴度可能是淋巴结转移的保护因素,但两者的相互关系尚需进一步探讨。     

HIF-1a、VEGF和CXCR4在甲状腺乳头状癌中的表达及意义

目的研究乏氧诱导因子1a(HIF-1a)、血管内皮生长因子(VEGF)和趋化因子受体4(CXCR4)在甲状腺乳头状癌组织中的表达及与临床病理因素的关系。方法应用免疫组化SP法检测120例甲状腺乳头状癌组织和60例正常对照组织中的HIF-1a、VEGF及CXCR4的表达情况,统计分析相关临床病理因素。结果 HIF-1a、VEGF及CXCR4在甲状腺乳头状癌中的阳性表达率分别为65.0%(78/120)、56.8%(68/120)、60.0%(72/120);三者的阳性表达与甲状腺乳头状癌的淋巴结转移及临床病理分期密切相关(P0.01);三者的表达之间存在一定的相关性(P0.05)。多因素分析发现,TNM分期,HIF-1a和CXCR4与甲状腺乳头状癌淋巴结转移密切相关(均P0.05)。结论 HIF-1a、VEGF及CXCR4与甲状腺乳头状癌的发生、发展相关,特别在甲状腺乳头状癌淋巴结转移中发挥重要作用,三者的检测在甲状腺乳头状癌的临床诊断及治疗中具有重要的指导意义。     

甲状腺乳头状癌合并桥本氏甲状腺炎的BRAF基因表达及侵袭性

目的:比较甲状腺乳头状癌合并桥本氏甲状腺炎与不合并桥本氏甲状腺炎的BRAFV600E基因表达以及侵袭性的区别。方法:2011年9月到2013年9月四川大学华西医院手术治疗并有BRAFV600E基因测定的甲状腺乳头状癌患者226名,均有病理证实。其中合并桥本氏甲状腺炎者50例为研究组,同期随机抽取50例不合并桥本氏甲状腺炎者作为对照组。比较两组性别、年龄、肿瘤大小、数量、BRAFV600E基因表达以及甲状腺外侵犯和淋巴结转移与侵袭性相关的因素的区别。结果:甲状腺乳头状癌合并桥本氏甲状腺炎在男女性别,发病年龄、肿瘤大小上和对照组相比无差异(P0.05);BRAFV600E突变率、甲状腺外侵犯和淋巴结转移都较对照组更低(P0.05)。BRAF基因突变阳性组甲状腺外侵犯和淋巴结转移率较BRAFV600E基因突变阴性组更高(P0.05)。结论:BRAFV600E基因突变的甲状腺乳头状癌患者有更高的甲状腺腺外侵犯和淋巴结转移。甲状腺乳头状癌合并桥本氏甲状腺炎较不合并桥本氏甲状腺炎有着更低的BRAFV600E突变率,更低的甲状腺外侵犯和淋巴结转移。     

甲状腺癌组织MVD和β-连环素蛋白表达及其相关性研究

目的:探讨微血管密度(MVD)和β-catenin蛋白表达在甲状腺癌预后判断中的意义.方法:采用免疫组化SP法检测90例甲状腺癌及10例正常甲状腺组织中β-catenin蛋白表达,以CD105标记测定MVD.结果:①MVD值在甲状腺髓样癌、乳头状癌、未分化癌、滤泡癌中依次增高(P＜0.05);伴发转移及高临床分期(Ⅲ、Ⅳ期)甲状腺癌组织中MVD明显高于无转移及低临床分期(Ⅰ、Ⅱ期)组(P＜0.05).②未分化癌及髓样癌中β-catenin异常表达率显著高于其在乳头状癌及滤泡癌中的表达(P＜0.05),β-catenin异常表达率在淋巴结有无转移间以及病理分期Ⅰ-Ⅱ、Ⅲ-Ⅳ之间的差异有统计学意义(P＜0.05).③β-catenin异常表达与甲状腺癌MVD值呈显著正相关(r=0.384,P＜0.05).结论:MVD是影响甲状腺癌预后的因素之一,β-catenin可能在甲状腺癌组织微血管形成中发挥作用.     

VEGF-D在甲状腺癌组织中的表达和意义

目的:探讨甲状腺癌中血管内皮生长因子-D(Vascular Endothelial Growth Factor,VEGF-D)在甲状腺癌中的表达及意义.方法:免疫组织化学染色方法分别对16例癌周正常组织和56例甲状腺癌组织切片染色,观察癌周正常组织和甲状腺癌组织VEGF-D的表达情况.结果:(1)在甲状腺癌中VEGF-D阳性表达主要见于细胞的胞膜上和胞质中.VEGF-D阳性表达在癌周正常组织和甲状腺癌分别为18.7%和71.4%,两者在统计学上有显著差异.(2)在甲状腺癌中VEGF-D在淋巴结非转移组表达阳性率为60.0%,而转移组表达为83.8%,明显高于非转移组,两者问在统计学上有显著差异.(3)在甲状腺乳头状癌中VEGF-D阳性表达在非转移组50%,淋巴结转移组85.1%,明显高于非转移组,说明VEGF-D在淋巴结转移组比非淋巴结转移组表达显著,VEGF-D的阳性表达与甲状腺癌的淋巴结转移显著相关.结论:(1)在癌周甲状腺组织VEGF-D阳性反应较弱,在甲状腺癌组织VEGF-D阳性反应较强,两者比较有显著性差异.(2)在甲状腺癌中,尤其是甲状腺乳头状癌中,其癌组织中VEGF-D的表达强度增加,与无淋巴结转移的甲状腺癌组织相比,有淋巴结转移的甲状腺癌组织中VEGF-D的表达较强,可作为肿瘤转移的指标之一.     

微小RNA-205 在甲状腺乳头状癌中的表达及临床意义

目的:观察微小RNA(microRNA,miRNA,miR)-205在甲状腺乳头状癌(PTC)中的表达并探讨其临床意义。方法:收集自2014年1月至2014年12月在我院甲状腺外科住院治疗的甲状腺乳头状癌患者的术后新鲜病理组织45例,其中男14例,女31例,年龄24-69岁,平均45.5岁。结节性甲状腺肿28例,癌旁正常甲状腺组织5例。提取各组织中的miRNA,应用实时荧光定量聚合酶链反应(RT-q PCR)方法检测miR-205的表达情况。结果:甲状腺乳头状癌miR-205的表达量较非肿瘤组织(结节性甲状腺肿、癌旁组织)明显下调[(1.06±1.76)vs(3.19±4.88),P=0.038]。伴淋巴结转移的PTC组织中miR-205表达量明显低于无淋巴结转移的PTC组织[(1.21±1.80)vs(9.59±1.60),P=0.003]。miR-205的相对表达与PTC患者性别、年龄及浸润与否均无显著相关性,而肿瘤直径呈显著相关性。结论:miR-205在PTC中的表达异常下调,可能与PTC的发生、侵袭和转移有关。     

Nomogram to Assess the Risk of Central Cervical Lymph Node Metastasis in Patients With Clinical N0 Papillary Thyroid Carcinoma

ObjectiveTo develop and validate an individualized risk prediction model for the need for central cervical lymph node dissection in patients with clinical N0 papillary thyroid carcinoma (PTC) diagnosed using ultrasound.MethodsUpon retrospective review, derivation and internal validation cohorts comprised 1585 consecutive patients with PTC treated from January 2017 to December 2019 at hospital A. The external validation cohort consisted of 406 consecutive patients treated at hospital B from January 2016 to June 2020. Independent risk factors for central cervical lymph node metastasis (CLNM) were determined through univariable and multivariable logistic regression analysis. An individualized risk prediction model was constructed and illustrated as a nomogram, which was internally and externally validated.ResultsThe following risk factors of CLNM were established: a solitary primary thyroid nodule’s diameter, shape, calcification, and capsular abutment-to-lesion perimeter ratio. The areas under the receiver operating characteristic curves of the risk prediction model for the internal and external validation cohorts were 0.921 and 0.923, respectively. The calibration curve showed good agreement between the nomogram-estimated probability of CLNM and the actual CLNM rates in the 3 cohorts. The decision curve analysis confirmed the clinical usefulness of the nomogram.ConclusionThis study developed and validated a model for predicting the risk of CLNM in individual patients with clinical N0 PTC, which should be an efficient tool for guiding clinical treatment.     

青岛地区某医院12年甲状腺癌发病模式变迁

目的:探讨青岛地区某医院12年甲状腺癌的发病趋势和病理类型分布。方法:回顾性分析2001-2012年于青岛大学附属医院行手术切除的甲状腺癌患者的发病年龄、性别比例、手术数量以及病理类型构成比的变化。结果:12年来手术治疗甲状腺癌2421例,其中乳头状癌(PTC)占94.13%,滤泡状癌(FTC)占3.02%,髓样癌(MTC)占2.15%,未分化癌(ATC)占0.70%。甲状腺癌手术数量呈逐年递增趋势,尤以近4年升高显著,其病理类型以PTC为主,构成比例由79.63%上升至97.47%。四类甲状腺癌均以女性多见(男女比例1:1.38-1:4.37)。甲状腺癌的平均确诊年龄为46.80岁,PTC最低(46.48岁),ATC最高(64.25岁)。结论:青岛地区甲状腺癌发病数量呈逐年递增趋势,PTC是最常见的病理类型,其构成比例上升明显,其他类型相对下降。PTC的发病可能与高碘有关。     

IGFBP7在甲状腺乳头状癌中的表达及意义

目的观察胰岛素样生长结合蛋白-7(IGFBP7)在甲状腺乳头状癌中的表达及意义。方法对87例甲状腺乳头癌(PTC)组织及癌旁组织(PeT)进行IGFBP7、Ki67、p53免疫组织化学分析,其中10例提取蛋白用半定量western blot方法进行IGFBP7表达水平分析。结果 (1)IGFBP7免疫组化显示,PTC癌组织IGFBP7阳性率达78.16%(68/87),明显高于癌旁组织的31.03%(27/87)(P0.05);(2)Western blot灰度值比较,癌组织IGFBP7表达水平显著高于癌旁组织(t=2.875,P0.05);(3)Ki67、p53与IGFBP7相关性分析显示,p53表达水平与IGFBP7表达水平呈显著正相关性(r=0.261,P0.05),而Ki67表达水平与IGFBP7表达水平无相关性(r=0.148,P=0.170);(4)高水平表达的IGFBP7与PTC淋巴结转移高度相关(r=0.238,P0.05)。结论 IGFBP7表达异常增高可能与甲状腺乳头状癌发生及发展有关,有望成为诊断PTC的一项新型的生物标记物。     

Risk Factors for Central Lymph Node Metastasis in CN0 Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Background

Central lymph node metastasis (CLNM) is common in papillary thyroid carcinoma (PTC). Prophylactic central lymph node dissection (PCLND) for patients with clinically negative central compartment lymph nodes (CN0) remains controversial. The phrase “clinically negative” is used to indicate that patients exhibited no clinical evidence of CLNM by ultrasonography (US) or computerized tomography (CT) preoperatively. In this study, we analyze the risk factors for CLNM in CN0 patients.

Methods

The PUBMED and SCIE databases were systematically searched for works published through January 31, 2015. All of the patients included in this study underwent thyroidectomy+PCLND. Revman 5.3 software was used to analyze the data.

Results

Twenty studies and 9084 patients were included in this meta-analysis. The following variables were associated with an increased risk of CLNM in CN0 patients: age < 45 years (OR = 1.59, 95% CI = 1.42–1.78, p<0.00001), male sex (OR = 1.95, 95% CI = 1.63–2.32, p<0.00001), multifocality (OR = 1.43, 95% CI = 1.22–1.67, p<0.00001), tumor size > 2 cm for PTC patients (OR = 2.98, 95% CI 2.08–4.28, p<0.00001) or tumor size > 0.5 cm for papillary thyroid microcarcinoma (PTMC) patients (OR = 2.30, 95% CI = 1.71–3.09, p<0.00001), location of the primary tumor in the central area and low pole (OR = 1.86, 95% CI = 1.48–2.33, p<0.00001), lymphovascular invasion (OR = 4.35, 95% CI = 2.24–8.46, p<0.0001), extrathyroidal extension (OR = 2.27, 95% CI = 1.76–2.94, p<0.00001), and capsular invasion (OR = 1.72, 95% CI = 1.39–2.41, p<0.00001). PTC (tumor size>1cm) exhibited a higher risk factor associated with CLNM than PTMC (tumor size<1cm) (OR = 2.83, 95% CI = 2.15–3.72, p<0.00001). Bilateral tumors (OR = 1.21, 95% CI = 0.92–1.58, p = 0.17) and lymphocytic thyroiditis (OR = 0.88, 95% CI = 0.71–1.09, p = 0.25) had no association with CLNM in CN0 patients.

Conclusions

Our systematic review identified several clinical features associated with CLNM in CN0 patients, including age, sex, multifocality, size, location, lymphovascular invasion, capsular invasion, and extrathyroidal extension. These factors should guide the application of PCLND in CN0 patients.     

桥本氏病合并甲状腺乳头状癌患者血清甲状腺相关激素水平的变化及意义

目的:探究桥本氏病(HT)合并甲状腺乳头状癌(PTC)患者血清甲状腺相关激素水平的变化及意义。方法:对我院148例HT患者的临床资料进行回顾性分析,根据其是否合并PTC分为HT合并PTC组(n=68)和单纯HT组(n=80)。比较两组患者性别、年龄及血清促甲状腺激素(TSH)、甲状腺功能指标[游离三碘甲腺原氨酸(FT3)、游离甲状腺素(FT4)]、抗甲状腺抗体[甲状腺球蛋白抗体(TGAb)、甲状腺过氧物酶抗体(TPOAb)]水平等临床资料差异,分析血清TSH水平变化及意义。结果:HT合并PTC组患者男性比例、年龄、病程及血清TSH水平均大于单纯HT组,血清TGAb、TPOAb水平则均小于单纯HT组(P0.05);血清FT3、FT4水平比较差异无统计学意义(P0.05)。HT合并PTC患者组血清TSH4.2 m IU/L患者占比高于血清TSH正常组(P0.05)。血清TSH4.2 m IU/L患者中HT合并PTC患者的占比大于血清TSH水平正常的患者(P0.05)。HT合并PTC患者中,血清TSH水平4.2 m IU/L患者中央区淋巴结转移发生率高于血清TSH水平正常患者(P0.05);血清TSH4.2 m IU/L与血清TSH正常患者多灶癌发生率比较差异无统计学意义(P0.05)。结论:HT患者血清TSH水平升高可能促进其甲状腺组织癌变,HT合并PTC患者血清TSH水平升高可能促进其中央区淋巴结转移。     

RET/PTC Rearrangements Are Associated with Elevated Postoperative TSH Levels and Multifocal Lesions in Papillary Thyroid Cancer without Concomitant Thyroid Benign Disease

RET/PTC rearrangements, resulting in aberrant activity of the RET protein tyrosine kinase receptor, occur exclusively in papillary thyroid cancer (PTC). In this study, we examined the association between RET/PTC rearrangements and thyroid hormone homeostasis, and explored whether concomitant diseases such as nodular goiter and Hashimoto''s thyroiditis influenced this association. A total of 114 patients diagnosed with PTC were enrolled in this study. Thyroid hormone levels, clinicopathological parameters and lifestyle were obtained through medical records and surgical pathology reports. RET/PTC rearrangements were detected using TaqMan RT-PCR and validated by direct sequencing. No RET/PTC rearrangements were detected in benign thyroid tissues. RET/PTC rearrangements were detected in 23.68% (27/114) of PTC tissues. No association between thyroid function, clinicopathological parameters and lifestyle was observed either in total thyroid cancer patients or the subgroup of patients with concomitant disease. In the subgroup of PTC patients without concomitant disease, RET/PTC rearrangement was associated with multifocal cancer (P = 0.018). RET/PTC rearrangement was also correlated with higher TSH levels at one month post-surgery (P = 0.037). Based on likelihood-ratio regression analysis, the RET/PTC-positive PTC cases showed an increased risk of multifocal cancers in the thyroid gland (OR = 5.57, 95% CI, 1.39–22.33). Our findings suggest that concomitant diseases such as nodular goiter and Hashimoto''s thyroiditis in PTC may be a confounding factor when examining the effects of RET/PTC rearrangements. Excluding the potential effect of this confounding factor showed that RET/PTC may confer an increased risk for the development of multifocal cancers in the thyroid gland. Aberrantly increased post-operative levels of TSH were also associated with RET/PTC rearrangement. Together, our data provides useful information for the treatment of papillary thyroid cancer.     

Cytologic features of metastatic papillary thyroid carcinoma in cervical lymph nodes

OBJECTIVE: To elucidate the cytologic characteristics of metastatic papillary thyroid carcinoma (PTC) in cervical lymph nodes and the differences in cervical lymph nodes from those of stage I (intrathyroidal) PTC. STUDY DESIGN: Forty-seven cases of papillary thyroid carcinoma with cervical lymph node metastasis (group A) and 38 cases of intrathyroidal papillary carcinoma (group B) were included in this study. Preoperative fine needle aspiration cytology (FNAC) examination was performed on enlarged cervical lymph nodes (47 cases, group A) and enlarged thyroid nodules (13 cases, group A, and 38 cases, group B). All the cases were surgically excised and pathologically verified. The cytologic smears were reviewed and analyzed. RESULTS: The cytologic characteristics of metastatic PTC in cervical lymph nodes displayed a higher frequency of foamy macrophages (51.1% vs. 26.3%) and a lower frequency of distinct cell borders (38.3% vs. 71.1%) than those of stage I PTC. Metastatic PTC in cervical lymph nodes also had a higher frequency of cystic degeneration (44.7% vs. 5.3%) than intrathyroidal lesions. In 1 of the 47 cases with lymph node metastasis, the aspirate contained macrophages but no tumor cells. CONCLUSION: FNAC was useful in the diagnosis of metastatic PTC in cervical lymph nodes. However, because cystic degeneration appeared frequently, FNAC combined with thyroid ultrasonography to find the primary lesion is necessary in this situation.     

Analysis of the expression of RET/PTC oncogenes in post-chernobyl papillary thyroid carcinomas of patients from different age groups

A comparative analysis of the expression of both, RET/PTC1 and RET/PTC3 oncogenes in papillary thyroid carcinomas (PTC) of patients from different age groups was carried out. Those were the following groups: children (mean age - 13 years, mean latency period - 13 years), young adults (mean age - 24 years, mean latency period - 14 years), adults (mean age - 38 years, mean latency period - 22 years). The presence of RET/PTC oncogenes was detected using polymerase chain reaction. In all cases the samples of both tumor and normal thyroid tissue were studied. It was established that induction of both, RET/PTC1 and RET/PTC3 rearrangements was present only in carcinoma samples. In PTCs the percentage of RET/PTC-positive tumors with increasing the age of patients has been decreasing. It should be noted that the part of carcinomas with induction of RET/PTC1 did not change with increasing the age of patients. At the same time the frequency of RET/PTC3 rearrangements with the increasing both the latency period and age of patients, significantly decreased. In conclusion, our data can evidence for the presence of correlation between the age of patients, latency period and induction of RET/PTC3 oncogenes.     

Molecular changes in thyroid neoplasia

All authors integrating the known facts into a model of thyroid carcinogenesis concur that two main histotypes of thyroid cancer exhibit different routes of molecular development. RET rearrangements are an initiating event in papillary carcinoma, and simultaneously the most characteristic mutation for this type of cancer. They are followed by further, not well recognized, mutations. RAS mutations are regarded as a crucial event in the development of follicular tumors already at the adenoma step, while in papillary cancer they belong to the spectrum of secondary mutations, enabling tumor progression. Aberrant DNA methylation, causing loss of P16 tumor supressor gene, may be a common event in both types of cancer. Aneuploidy is seen much more frequently in follicular than in papillary cancer, which also exhibits a low rate for loss of heterozygosity and microsatellite instability. Mutations of the P53 tumor supressor gene are a common feature of undifferentiated thyroid cancers and could be responsible for their aggressive phenotype. RET rearrangements have been proposed as identifying fingerprints for irradiation induced thyroid cancer in children. Our own data speak against this hypothesis. We noted a high frequency of RET/PTC3 mutations in a group of Polish children with papillary thyroid carcinoma, regarded as sporadic cancer.