Changing patterns of thyroid carcinoma

Background  To assess changing trends in histological types of thyroid cancer in an Irish hospital over the past 30 years. Methods  Biographical data, tumour characteristics, treatment and outcome from 190 patients with thyroid carcinoma from 1970 to 2000 were reviewed retrospectively. Results  Detailed records of 190 patients with thyroid cancer were identified with a mean age at presentation of 50 years. From 1970 to 1979 the distribution of histological types was: papillary carcinoma; 9 patients (4.7%), follicular; 17 patients (8.9%), anaplastic; 9 patients (4.7%), medullary; 1 patient (0.5%) and lymphoma; 1 patient (0.5%). From 1980 to 1989 papillary carcinoma accounted for 32 patients (16.8%), follicular; 14 patients (7.3%), anaplastic; 13 patients (6.8%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). From 1990 to 1999 papillary cancer accounted for 48 patients (25.2%), follicular; 14 patients (7.3%), anaplastic; 8 patients (4.2%), medullary; 7 patients (3.7%) and lymphoma; 5 patients (2.6%). Survival rates were significantly better for those aged less than 45 years (P < 0.0001), female sex (P < 0.01) and those with papillary carcinoma (P < 0.01). Conclusions  This study demonstrated a significant increase in the incidence of papillary carcinoma. This may be related to increasing dietary iodine intake and may be significant as papillary carcinoma is associated with a more favourable prognosis.     

甲状腺结节细针穿刺检查782例临床病理分析

目的分析甲状腺结节细针穿刺（FNAB）检查的诊断结果及其应用价值。方法回顾性分析782例行FNAB检查患者的临床病理资料。细胞病理诊断分为6类,为未诊断、良性病变、滤泡性病变、滤泡性肿瘤、可疑恶性和恶性。对其中手术治疗的76例患者的组织病理与细胞病理进行对比,判断细针穿刺的准确性。结果782例行FNAB检查患者中,良性病变占74．4％（582／782）,恶性诊断只占2．6％（20／782）,滤泡性肿瘤占5．6％（44／782）,滤泡性病变、可疑恶性分别为3。2％（25／782）和2．9％（23／782）,未诊断者占11．3％（88／782）。76例手术患者中,组织病理诊断良性疾病占65．8％（50／76）,恶性肿瘤占28．9％（22／76）,良性肿瘤占5．3％（4／76）。在细胞病理诊断为良性和恶性两大类中,与组织病理的符合率较高,分别为16／16和16／17。结论甲状腺细针穿刺是甲状腺结节诊断和鉴别诊断的可靠方法。     

甲状腺肿瘤ras-p21及EBV LMP-1的表达及意义

目的研究ras癌基因及EBV感染在甲状腺癌中的意义。方法应用SABC免疫组化法对88例甲状腺肿瘤(乳头状癌34例,滤泡性癌17例,髓样癌5例,未分化癌8例,腺瘤24例)进行研究,观察ras癌基因蛋白产物p21及EBvLMP-1的表达情况。结果甲状腺癌p21的表达与甲状腺肿瘤良恶性有关,甲状腺癌p21阳性率(62.5％)明显高于甲状腺腺瘤(33.3％)(P<0.05)。甲状腺癌p21与组织学分型无关。LMI-1在甲状腺癌中的表达率为15.6％,癌周组织无表达。结论ras癌基因突变为甲状腺癌发生中的早期事件,p21检测可作为甲状腺滤泡性肿瘤良恶性鉴别的辅助指标,提示EBV感染与甲状腺癌的发生有关。     

Histopathological profile of childhood thyroid carcinoma in Ibadan,Southwestern Nigeria

BackgroundThyroid carcinoma is a common endocrine malignancy. It is however rare in childhood and often occurs as a result of radiation exposure or inherited genetic mutations. Most childhood thyroid carcinomas are well differentiated. There are very few epidemiological studies of this disease in Nigeria and our study aimed to determine the frequency in a subset of our population. The study aimed to determine the prevalence and histopathological characteristics of childhood thyroid carcinoma in our environment.MethodsThis was a retrospective review of histopathologically diagnosed thyroid carcinoma in children less than 18 years of age in the Department of Pathology, University College Hospital, Ibadan over a 40-year period. Histopathological diagnosis, age, sex and other relevant clinical information were extracted from the hospital records and surgical pathology records of the department. All cases of patients under18 years old had their slides re-examined and reclassified by two pathologists according to the World Health Organization histopathological classification of thyroid tumours.ResultsThere were 25 cases of thyroid carcinomas seen in children within the study period. Papillary thyroid carcinoma was the most common, accounting for 80% of the cases. Follicular carcinoma accounted for 12%, and medullary and anaplastic carcinoma accounted for 4% each. The mean age at presentation was 13 years. There was a female preponderance with females accounting for 60% of cases. Tumours with distant metastasis made up 20% of the cases.ConclusionChildhood thyroid carcinomas are rare in our environment, with a minority of cases presenting with metastases.     

甲状腺癌ret、ras、p53基因的表达及意义

目的通过对甲状腺癌ret、ras、p53基因研究,揭示其在甲状腺癌发病中的意义,为进一步进行甲状腺癌的防治奠定基础。方法用免疫组织化学方法检测66例甲状腺癌和102例甲状腺良性病变中ret、ras、p53基因的表达并进行比较。结果ret在甲状腺乳头状癌、滤泡状癌、未分化癌、结节性甲状腺肿、桥本病及甲亢中均有表达,在髓样癌和滤泡状腺瘤中未检测到;ras在各型甲状腺病中均有表达,但在乳头状癌、滤泡状腺瘤及桥本病中的阳性率明显高于其他类型,差异有统计学意义（P〈0．05）;p53在各型甲状腺癌中的表达率为20％～50％,良性病变中仅在1例滤泡状腺瘤和3例结节性甲状腺肿中呈阳性。ret、p53在甲状腺癌中的表达显著高于甲状腺良性病变,差异有统计学意义（P=0．001）;ras在甲状腺良恶性病变中均有较高表达,差异无统计学意义（P=1．000）。结论甲状腺癌的发病与癌基因ret、ras及抑癌基因p53的突变有密切联系。ret、p53在甲状腺癌中的表达显著高于甲状腺良性病变;ras在甲状腺良恶性病变中均有较高表达,但在乳头状癌、滤泡状腺瘤及桥本病中的阳性率明显高于其他类型。因此,甲状腺癌的防治除考虑高碘因素外,也应充分注意遗传因素的影响。     

Metastasis in differentiated thyroid carcinoma

Seventy patients of differentiated thyroid carcinoma (DTC) irrespective of age and sex were selected in ENT Department of Bangabandhu Sheikh Mujib Medical University, Dhaka Medical College Hospital and Rangpur Medical College Hospital who were admitted from March 2003 to March 2005. Female were more commonly affected (2.6:1) Papillary carcinoma was more common in 31-50 years of age and follicular carcinoma (ca) common in 41-50 years of age. Among the differentiated thyroid carcinoma papillary carcinoma found 77.15% and follicular ca. found 22.85%. Lymph node metastasis was more common in papillary (35%) than follicular carcinoma (12.5%). But distant metastasis was more common in follicular (12.5%) than papillary carcinoma (3.70). Maximum lymph node metastasis was found in level 3(55%), level 2(45%).     

核仁组成区嗜银蛋白在甲状腺良恶性病变中的定量研究

应用银染技术定量研究了57例甲状腺良恶性病变中核仁组成区嗜银蛋白(AgNOR)的数目和分布.计数结果;正常甲状腺细胞核AgNOR计数平均为2.51,腺瘤4.61,乳头状癌5.60,髓样癌与滤泡癌9.76,未分化癌11.86,均数差别有统计学意义。此外,AgNOR在不同类型的癌中分布形式也有差别,乳头状癌多呈较规则的团块,未分化癌则呈多而不规则的团块及较多散在颗粒,滤泡癌介于两者之间.表明AgNOR方法不仅可以作为定量或半定量指标区分甲状腺良恶性肿瘤,而且提示与癌分型和临床预后相关。     

A histopathological analysis of thyroid diseases in Ile-ife, Nigeria. a review of 274 cases

OBJECTIVE: To describe the spectrum of histopathological features of thyroid diseases; analyse the occurrence of each of the types and to compare the findings with those from previous studies done in Nigeria and elsewhere. MATERIALS AND METHODS: A retrospective study of thyroid lesions seen at the OAUTHC Histopathology Department during a 10-year period between 1988 and 1997. RESULTS: The 274 surgical thyroid specimens received during the study period came from 235 (85.8%) females and 39 (14.2%) males giving a female: male ratio of 6:1. Colloid goiter accounted for about 75% of cases with an average age of occurrence of 40.7 years. Only 1.8% showed features of toxic goiter and thyroiditis each. The adenomas constituted about 6% while carcinomas constituted about 11% of cases respectively. Adenomas occurred almost a decade earlier than carcinomas. Follicular carcinoma was the commonest thyroid cancer seen in this study. CONCLUSION: This study shows that the commonest thyroid disease in Ile-Ife is colloid goiter, which is a preventable disease. Thus, public health measures such as iodination of salt and health education are called for to reduce the occurrence of this disease.     

BP1基因在甲状腺癌组织中的表达及其临床意义

目的检测BP1在甲状腺癌组织中的表达,探讨其与甲状腺癌临床病理因素的关系。方法运用原位杂交及免疫组化方法检测60例甲状腺癌组织（研究组）和20例正常甲状腺组织（对照组）中的BP1表达。结果原位杂交方法检测BP1mRNA阳性率在研究组中为78．3％（47／60）,对照组中为20％（4／20）,BP1基因在2组的表达差异有统计学意义（x。=22．09,P〈0．05）;甲状腺癌各病理类型的阳性表达率分别为乳头状癌81．7％（40／49）、滤泡状癌85．7％（6／7）、髓样癌25．0％（1／4）;髓样癌分别与乳头状癌、滤泡状癌之间BP1mRNA的表达差异有统计学意义（,=4．21,P〈0．05）;免疫组化检测研究组中BP1蛋白阳性率为93．3％（56／60）,对照组中BP1蛋白阳性率为10．0％（2／20）,2组间BP1的表达差异有统计学意义（χ2=52．25,P〈0．05）。国际抗癌联盟（UICC）Ⅰ～Ⅱ期BP1mRNA阳性率90．9％（40／44）,Ⅲ～Ⅳ期43．8％（7／16）,差异有统计学意义（χ2=12．72,P〈0．05）。但BP1mRNA表达与性别、年龄及淋巴结转移无相关性。结论BP1在甲状腺癌组织中的表达显著上调;BP1基因的表达与其UICC分期、病理学类型有关,而与年龄、性别及淋巴转移无关。     

Clinicopathological correlation of serum TSH in patients with thyroid nodule

Thyroid nodules and goitre are common. Carcinoma occurs in 5% of thyroid nodules. Early detection and treatment is beneficial to prolonged survival. Higher thyroid stimulating hormone (TSH) level in patient with thyroid nodule is associated with greater risk of differentiated thyroid carcinoma. To assess relationship of TSH with thyroid carcinoma in nodular goitre and usefulness of this marker in predicting likelihood of thyroid malignancy, a study was undertaken among patients with nodular goitre enrolled prospectively during the period 2007 to 2009. Clinically thyroid nodules, confirmed by high resolution USG underwent serum TSH estimation and FNAC of the the nodules. Finally outcome of histopathological examination of resected thyroid specimen were analysed. Overall 33 patients with thyroid nodules were included in this study. Fifteen patients belonged to age group of 31 to 40 years, 13 belonged to 21 to 30 years; 29 were women, 4 were men. Majority of nodules were in right lobe and firm or hard. Fifteen nodules were > 4cm in size. FNAC showed colloid goitre in 24 patients, 7 patients had papillary carcinoma, 2 patients had follicular nodule. Final histopathological report showed 9 papillary carcinoma, 1 medullary carcinoma, 1 follicular carcinoma, 2 follicular adenoma and rest being colloid goitre. Mean TSH value for colloid goitre was 1.8987 mlU/l, for papillary carcinoma it was 2.2400 mlU/l, for follicular carcinoma it was 2.8900 mlU/l, for medullat carcinoma it was 0.8500 mlU/l and for follicular adenoma it was 4.4200 mlU/l. In differentiated thyroid carcinoma TSH value is raised more than in colloid goitre (p = 0.687). Incidence of malignancy in nodular goitre was 30% (11 carcinoma out of 33) in this study. Incidence of malignancy in nodular goitre is rising. Firm to hard nodules, male sex, 3-4 cm sized nodules are mainly susceptible. There is an obvious trend towards cancer risk with higher TSH value. TSH may, therefore, be used as a supportive screening test to predict malignancy in patients with thyroid nodule.     

Pattern of malignancy in clinically solitary thyroid nodule

Solitary thyroid nodule (STN) is a common thyroid disorder. Clinically recognized thyroid carcinoma constitutes less than 1% of human malignant tumours. The risk of malignancy in solitary thyroid nodule is greater than other thyroid swelling. The risk of malignancy in generalized thyroid swelling is about 3% and in solitary thyroid nodule it is about 15%. This study was carried out in Surgery and ENT Department, Mymensingh Medical college Hospital from November 2008 to October 2009 to see pattern of malignancy in clinically solitary thyroid nodule. Total 108 patients of STN was included in this study, majority of the patients were within 20-39 years age group with female predominance. In addition to thyroid swelling some patients presented with other symptoms like cervical lymphadenopathy in 6(5.56%), dysphagia 2(1.85%), hoarseness of voice 2(1.85%) and metastatic lesion in bone 1(0.92%) cases. Among 108 cases of solitary thyroid nodule only 19 cases were malignant. Patients with malignant lesion presented with shorter duration of symptoms. Out of 19 malignant cases 6(31.58%) cases presented with features of metastasis. Malignancy was more predominant in male (25.00%) than the female (14.47%) in STN. Out of 19 malignant cases, 12(63.16%) were papillary carcinoma, 5(26.31%) were follicular carcinoma and 2(10.53%) cases were medullary carcinoma. Study showed significant difference (p<0.01) between papillary & follicular carcinoma and significant difference (p<0.001) between papillary & medullary carcinoma. Papillary carcinoma was most common among all thyroid malignancies in patients with solitary thyroid nodule.     

PTTG1IP在甲状腺滤泡上皮细胞起源肿瘤中的表达及意义

目的 探讨PTTG1IP蛋白在甲状腺滤泡上皮细胞起源的不同肿瘤中的表达情况及意义。方法 应用免疫组织化学方法检测PTTG1IP蛋白在25例甲状腺癌旁正常组织、23例滤泡性腺瘤、65例乳头状癌、19例滤泡癌和18例未分化癌中的表达情况。结果 PTTG1IP蛋白表达率在甲状腺癌旁正常组织中为28%,在滤泡性腺瘤组织为30.43%,在乳头状癌组织为61.54%,在滤泡癌组织为31.58%,在未分化癌组织为22.22%。PTTG1IP蛋白在乳头状癌组织的表达率显著高于癌旁正常组织、滤泡性腺瘤组织、滤泡癌组织和未分化癌组织（P<0.05）。PTTG1IP蛋白表达率与甲状腺乳头状癌患者年龄、甲状腺外侵犯和TNM分期明显相关（P<0.05）。结论 在甲状腺滤泡上皮细胞起源的不同肿瘤中,PTTG1IP蛋白过表达可能在乳头状癌的始发和进展中发挥作用,而与滤泡癌和未分化癌的发生发展无关。PTTG1IP蛋白可能是鉴别乳头状癌与甲状腺良性病变及其他恶性滤泡上皮性肿瘤的一个有用指标。PTTG1IP可能为难治的甲状腺乳头状癌提供新的治疗靶点。     

甲状腺增生性病变中CK19、TPO、Galectin-3的表达及在病理诊断中的应用

目的:检测甲状腺增生性病变中CK19、TPO、Galectin3的表达情况,并评价其在甲状腺增生性病变诊断与鉴别诊断中的价值。方法:利用免疫组织化学染色EnVision二步法,对120例甲状腺病变组织中CK19、TPO、Galectin3蛋白的表达情况进行检测。结果:58例甲状腺乳头状癌(经典型乳头状癌+滤泡型乳头状癌)中,CK19、Galectin3阳性率均为100%(58/58);TPO阴性率约为84.5%(49/58)。25例滤泡性癌、15例甲状腺滤泡性腺瘤及15例结节性甲状腺肿,CK19、Galectin3多为阴性或弱阳性,而TPO均为阳性。CK19、TPO、Galectin3在经典型乳头状癌与良性增生(滤泡性腺瘤+结节性甲状腺肿)之间,滤泡型乳头状癌分别与滤泡性癌、滤泡性腺瘤之间进行比较,P<0.05,差异有显著性;而滤泡性癌与滤泡性腺瘤之间比较,P>0.05,差异无显著性。结论:CK19、TPO、Galectin3均有助于甲状腺乳头状癌与甲状腺良性增生的诊断与鉴别诊断;有助于甲状腺滤泡型乳头状癌与滤泡性癌的诊断与鉴别诊断;但对滤泡性癌与滤泡性腺瘤之间的诊断与鉴别诊断帮助不大;CK19、TPO、Galectin3联合检测有助于提高甲状腺增生性病变的诊断准确率。     

促甲状腺激素受体第十外显子基因突变与甲状腺癌发病的相关研究

〔摘要〕 目的 研究甲状腺癌发病是否与促甲状腺激素受体（TSHR）第十外显子基因突变有关。 方法 采用巢氏-多聚酶联反应－单链构象多态性分析方法（NEST-PCR-SSCP）及DNA测序方法,对76例甲状腺癌（其中10例滤泡型癌,65例乳头状癌,1例髓样癌）和44例对照组织TSHR第十外显子基因进行检测。结果 经NEST-PCR-SSCP检测甲状腺癌TSHR第十外显子未发现明显带型异常,第三片段(即第3胞内环)取2例对照组织和5例甲状腺癌组织进行DNA测序,7例组织TSHR2000位点碱基均由C→T,使得所编码的601位氨基酸由组氨酸(CAT)→酪氨酸(TAT)（His→Tyr）,余无明显基因突变。结论 甲状腺癌TSHR第十外显子未发现基因突变,提示甲状腺癌发病与TSHR第十外显子基因突变无关;由于所测7例标本601位氨基酸均为酪氨酸,考虑中国人TSHR基因与国外人群存在差异。     

Thyroid gland diseases in Kano

Goiter is endemic in some parts of Nigeria. Kano is populated by people from various geographical areas. There has not been any report of thyroid gland diseases pattern in Kano, hence the need for this study. A retrospective review of 75 cases of thyroid gland diseases seen and managed at Aminu Kano Teaching hospital, Kano over a 5-year period forms the basis for this study. Of the 75 patients with goiters 69(92% ) were females. Simple non-toxic goiter was the most common histologic type accounting for 51 (68.0% ) of cases. There were 10 cases (13.3% ) of thyrotoxicosis, 4 (5.4% )with follicular adenoma, and 10 (13.3% ) other patients had proven carcinoma. Well-differentiated follicular carcinoma was the most common malignant type, 7 of which were not recognised as such preoperatively. All cases were treated by surgery with minimal morbidity and mortality. Thyroid surgery constitutes a significant proportion of surgical practice in Nigeria. While increase in dietary iodine will reduce the incidence of goiter everywhere, the impact of iodinisation of salt is yet to be determined. A population based survey of the prevalence of thyroid gland disease in Kano northwest, Nigeria is strongly indicated.     

ghrelin在甲状腺疾病组织中的表达

目的:探讨ghrelin在不同甲状腺疾病的甲状腺组织中的表达情况及其意义.方法:选取我院2000年至2004年手术切除或穿刺活检的甲状腺石蜡标本57例,其中包括亚急性甲状腺炎5例、桥本氏病8例、甲状腺机能亢进症(Graves病)7例、结节性甲状腺肿8例、甲状腺腺瘤5例、甲状腺淋巴瘤3例、乳头状癌8例、滤泡癌3例、髓样癌5例、未分化癌5例,以甲状腺腺瘤的瘤周正常甲状腺组织作为对照.应用免疫组织化学染色方法检测ghrelin的表达.结果:(1)正常对照、亚急性甲状腺炎、桥本氏病以及Graves病的甲状腺组织中均未见ghrelin表达;(2)结节性甲状腺肿、甲状腺腺瘤以及甲状腺淋巴瘤的组织中亦未见ghrelin表达;(3)甲状腺乳头状癌、滤泡癌、髓样癌及未分化癌的肿瘤细胞中均可见ghrelin阳性染色,8例乳头状癌中有5例染色阳性,其中3例为强阳性;3例滤泡癌中有2例染色阳性;5例髓样癌中有3例染色阳性,其中1例为强阳性;5例未分化癌中有3例染色阳性,其中2例为强阳性.结论:ghrelin在恶性上皮性甲状腺肿瘤中可见表达,而在自身免疫性或炎症性甲状腺疾病和良性甲状腺结节性疾病中未见表达.提示ghrelin表达在甲状腺恶性肿瘤的发生和发展过程中可能具有重要意义.     

甲状腺肿瘤组织神经降压素的免疫组化观察

应用免疫组织化学方法检测了６８例病理性甲状腺组织中神经降压素的分布。结果表明，３５例甲状腺乳头状腺癌中，神经降压素标记阳性反应率为９１％；９例甲状腺滤泡性腺癌及１０例甲状腺髓样癌中标记阳性率为１００％，甲状腺癌中神经降压素阳性颗粒分布于癌组织胞浆、滤泡上皮顶浆及胶质中。而在９例甲状腺腺瘤中８例呈阴性反应；５例甲状腺肿标本神经降压素标记均呈阴性反应。提示甲状腺癌可合成、分泌神经降压素，检测甲状腺标本中神经降压素标记阳性率，可作为甲状腺癌的辅助诊断及其鉴别诊断指标之一。     

Cytological patterns of thyroid lesions in Najran,Saudi Arabia: A 5-year retrospective study

Objectives:To assess the cytological pattern of thyroid lesions in Najran, Saudi Arabia.Methods:A retrospective study, from the period of January 2015 to December 2019. All patients with thyroid enlargement who were presented to different hospitals in Najran and assessed by fine needle aspiration cytology were included in this study.Results:Of 1353 cases, 1138 (84.1%) were female and 215 (15.9%) were male. Most of the thyroid lesions were benign (72.5%) including follicular nodules (39.5%), Hashimoto’s disease (21.2%), and colloid nodules (11.8%). There were 107 (7.9%)cases of suspicious malignancy, and the most common malignant tumor was papillary carcinoma (10.2%). The 2^nd age group (21-40 years) was the common age to be diagnosed with malignant tumors, particularly in males. The 3^rd age group (41-60 years) was most affected by thyroid lesions, particularly in females.Conclusion:Most of thyroid lesions in Najran were benign, and females were more affected by thyroid lesions than males. However, papillary carcinoma was the 4^th most frequent thyroid lesion in females, while it was the 2^nd most frequent in males and diagnosed mainly in younger males (21-40 years). Finally, ages 21-60 years were associated with most of the thyroid lesions in both males and females.     

P^16在甲状腺癌中的表达及意义

目的：研究Ｐ＾１６在甲状腺癌中的表达及意义。方法：应用ＳＰ免疫组化法检测５２例甲状腺癌的病例。结果：甲状腺癌中Ｐ＾１６的阳性率为７１．１％,乳头状癌最高,其次为滤泡癌,最低为未分化癌。癌与正常甲状腺组织及甲状腺腺瘤的表达有显著性差异。结论：Ｐ＾１６的低表达与甲状腺癌的发生有关并与癌的组织学类型有关。     

Microvessel Density in Thyroid Carcinoma and Its Clinical Significance

Objective: To investigate the relationships between angiogenesis and development, metastasis as well as prognosis of thyroid carcinoma. Methods:48 cases of thyroid carcinoma and 5 cases of thyroid adenoma were studied.Density of microvessels of the tumors were identified by immunohistochemical staining in formalin -fixed and paraffin-embedded sections with anti-CD34 monoclonal antibody, and counted microscopically (×200).Results :The mean value of MVD in tumors＞2cm in diameter was (174.92±72.63)/field, while that in tumors≤2cm was ( 117.40± 39.95)/field ( t = 3.3298, P = 0.0026).The number of microvessels was also significantly different in respect to the histotype of the thyroid carcinomas, such as papillary thyroid carcinoma(PTC), follicular thyroid carcinoma(FTC)and medullary thyroid carcinoma(MTC) ( F = 14. 95, P = 0. 0001), but not significantly different in respect to patients'age nor sex ( P＞0.05). Conclusions:By studying microvessel density (MVD) of thyroid arcinomas and correlated with their clinical features and biological behaviors, it is concluded that ngiogenesis is important in tumor growth and metastasis as well as prognosis of thyroid carcinomas. Measures to combat angiogenesis may be beneficial in the treatment for thyroid carcinomas.