The many faces and mimics of papillary thyroid carcinoma

This article provides an overview of the 15 histologic variants of papillary thyroid carcinoma listed by the 2004 World Health Organization (WHO) monograph on endocrine tumors. The histologic features, differential diagnosis, and clinical course of each variant are discussed in some detail. The follicular variants (conventional and macrofollicular) constitute a morphologic challenge because the majority of these tumors are encapsulated and, also, because, in many tumors, not all neoplastic cells show the nuclear features considered to be diagnostic of papillary carcinoma. As a result, most of these tumors are missed even by experienced pathologists. Moreover, hyperplastic thyroid lesions, follicular adenomas, and Hashimoto’s thyroiditis may contain cells with clear nuclei resembling those of papillary carcinoma. Papillary carcinomas composed entirely of hyperchromatic cells have been overlooked. The WHO monograph defines papillary carcinoma with focal spindle and giant cell carcinoma components but its clinical behavior is unknown. Papillary carcinoma with an insular pattern that does not show the artifactual separation of the cell nests has been misinterpreted as the solid variant of papillary carcinoma. Papillary microcarcinomas include not only the conventional type and the follicular variants but also the tall cell and columnar cell variants.     

Pancreatic metastasis of papillary thyroid carcinoma: a case report with review of the literature

In this article we give a case report on a PTC patient with pancreatic metastasis. In this case, the patient was admitted to our hospital for recurrence of PTC and occupying pancreatic lesions. We considered that the pancreatic neoplasm may be pancreatic metastasis of PTC but there is no previous experience about therapeutic approaches to this type of metastases. After some discussion the distant metastasis within the pancreas was successfully removed by a laparotomy and postoperative histology confirmed the diagnosis. After that surgery, the patient recovered well and then received total thyroidectomy and cervical lymph node dissection for recurrent thyroid cancer. After recovery he was discharged from hospital without further treatment. Eventually, he died of acute myocardial infarction in January 2010. To conclude, it is widely believed that the surgical operation should be chosen more positively in the management of those patients without multiple organ metastases. Thus on one hand it can serve to make a definite diagnosis, and on the other hand it can help the body get rid of the bulk of the tumor burden to prolong survival time of the patients.     

Identification of immunohistochemical biomarkers for papillary thyroid carcinoma using gene expression profiling

We report the successful validation of a combined gene expression profiling and tissue microarray approach to papillary thyroid carcinoma (PTC) biomarker identification. Our ultimate goal is the identification of protein biomarkers that can be effectively used in immunocytochemical assays applied to thyroid fine needle aspiration biopsy (FNAB) samples. To that end, we designed our approach to prioritize molecules that were minimally expressed in normal thyroid and highly expressed in PTC. We first generated gene expression profiles from 11 normal thyroid tissue samples and 9 samples of classic PTC. The results were segregated to rank most highly those molecules not expressed in normal thyroid and up-regulated at least 6-fold in PTC. From this list, we chose 2 molecules (P-cadherin and Bax) for immunohistochemical analysis for which commercial antibodies were available. These were compared with 2 other molecules that have been previously studied in thyroid cancer (cytokeratin-19 and galectin-3). For immunohistochemistry, a tissue microarray was generated that contained the following tissues: classic PTC (n = 20), follicular variant of PTC (n = 9), normal thyroid (n = 19), Hashimoto thyroiditis (n = 11), follicular adenoma (n = 15), and follicular carcinoma (n = 14). Immunohistochemical staining was scored and compared with the gene expression profiling. As anticipated, cytokeratin-19 and galectin-3 were highly expressed in PTC and less expressed in other tissues. Bax and P-cadherin were also expressed in PTC, but to a lower level than cytokeratin-19 and galectin-3; however, Bax and P-cadherin demonstrated virtually no staining of normal thyroid, unlike cytokeratin-19 and galectin-3. These results validate our approach for PTC biomarker discovery and identify several candidate biomarkers for further development.     

乳头状甲状腺癌差异表达基因的筛选及生存分析

目的利用生物信息学方法筛选乳头状甲状腺癌（PTC）的关键基因及其所在信号通路，探讨其致癌机制。方法 从基因表达综合数据库（GEO）的两个测序平台的7个GSE芯片中获得PTC和癌旁组织样本的数据。首先利用R语言分别筛选出两个测序平台样本的差异基因，然后通过Metascape和STRING对差异基因进行生物学功能、信号通路分析和蛋白质-蛋白质相互作用分析,最后利用Cytoscape 3.5.1软件筛选出关键基因。结果 两个测序平台的样本求交集共获得302个差异表达基因，其中149个基因上调，153个基因下调，利用Cytoscape 3.5.1软件筛选出15个关键基因，其中12个关键基因位于细胞外基质受体相互作用信号通路中。利用UALCAN数据库对15个关键基因进行生存分析，其中4个基因的表达水平变化与患者的生存时间紧密相关。结论 利用生物信息学技术对来自7个PTC基因芯片数据集的信息进行分析，弥补了小样本结果的不一致性，提高了结果的可靠性和稳定性，并且筛选出了15个关键基因，发现了细胞外基质受体相互作用信号通路在甲状腺癌的发生发展中的重要作用。     

Minichromosome maintenance protein 3 is a candidate proliferation marker in papillary thyroid carcinoma

The proliferative capacity of tumor cells is a characteristic feature in the whole growing tumors. Many pathologists and clinicians have used the estimation of cell proliferation for prognostic information. Minichromosome maintenance protein 3 (MCM3) is known to have a role on the initiation and regulation of DNA replication during cell cycle. The aim of this study was to evaluate the potential applicability of one of the MCM proteins, MCM3, as a proliferation marker in papillary thyroid carcinoma (PTC) with correlation to clinicopathological parameters. We performed the immunohistochemical analysis for MCM3 and Ki-67 in 60 cases of PTC and Western blot analysis for MCM3 expression in 6 PTCs and normal thyroid tissues. The comparison of MCM3 labeling index (LI) to tumor size (P = 0.031) and extrathyroidal extension (P = 0.037) was statistically significant while that of Ki-67 LI to them was not. Moreover, a significant association was not observed between MCM3 and Ki-67, but the MCM3 LI was considerably higher. Western blot analyses revealed that the MCM3 protein expression levels were overexpressed in all PTCs. On the contrary, the levels of MCM3 were very low or absent in all normal thyroid tissues. Our results indicate that MCM3 may be a more reliable proliferation marker than Ki-67 in accessing the growth of tumor and evaluating tumor aggressiveness of PTC.     

Risk factors influencing the recurrence of papillary thyroid carcinoma: a systematic review and meta-analysis

Objective: To evaluate the risk factors influencing the recurrence of papillary thyroid carcinoma. Methods: This meta-analysis used MEDLINE (PubMed), EMBASE and CNKI including all cohort studies reporting the risk factors influencing the recurrence after the initial operation on PTC up to February 23, 2014. Software RevMan 5.2 was used for meta-analysis. Results: Thirteen studies with a total of 7048 patients were included in our meta-analysis. Of all variables, gender, extrathyroid extension, LNM, tumor size, distance metastasis, thyroid surgery types and 131-I given or not were significantly correlated with recurrence, While overall recurrence was similar between the group of ≤ 45 years and > 45 years, multifolicality and solitary. However, when stratified the participants by study location (ie, Asian including China, Korea, Japan, Western country including America, France, Italy, Australia), a statistically significant summary odds ratio for age were found in Western country but none in Asian. Conclusion: The risk factors influencing recurrence includes male, extrathyroid extension, LNM, tumor size more than 2 cm, distance metastasis and subtotal thyroidectomy. However, selection of operation mode should be based on not only the recurrence but the comprehensive consideration of the clinical features.     

Histopathologic and immunohistochemical characterization of a primary papillary thyroid carcinoma in the lateral cervical lymph node

Lymph nodes in the neck are known to occasionally contain benign epithelial inclusions and can be rare primary site of various tumors usually occurring in other organs. Papillary thyroid carcinoma in the lateral neck lymph node with co-existing ectopic thyroid inclusions has not been reported previously. A 41-year-old male patient, who had normal thyroid function and no history of neck irradiation, was seen with a slowly enlarging mass in the right lateral neck. At surgery the cervical mass was found to be separate from the thyroid proper without any attachments in between. Papillary thyroid carcinoma and co-existing thyroid inclusions were identified within the lateral cervical lymph node. Immunohistochemistry detected strong and diffuse cytoplasmic positivity with antibodies against CK19 and CK903 in papillary thyroid carcinoma. Benign thyroid follicles within the lymph node were only weakly and focally stained. Thorough examination confirmed no malignancy in the total thyroidectomy specimen. Furthermore, small foci of metastatic papillary carcinoma were identified in two ipsilateral lymph nodes from neck dissection specimen. These findings suggest development of primary papillary thyroid carcinoma from malignant transformation of benign intranodal thyroid inclusions.     

Distinction between papillary thyroid hyperplasia and papillary thyroid carcinoma by immunohistochemical staining for cytokeratin 19, galectin-3, and HBME-1

The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis. Formalin-fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma from hyperplasia in diagnostically difficult cases.     

SUMO4在甲状腺乳头状癌中的表达及临床意义

目的:探讨小泛素相关修饰因子4(SUMO4)表达与甲状腺乳头状癌(PTC)发生发展的关系。方法:采用real-time PCR、Western blot及免疫组化等方法检测PTC和正常甲状腺组织中SUMO4的mRNA及蛋白表达情况,对比研究SUMO4蛋白表达与PTC及其临床病理特征的关系。结果:SUMO4的mRNA及蛋白表达量在PTC中均明显高于正常甲状腺组织(P0.01)。结论:SUMO4在PTC的高表达提示其在PTC发生发展中扮演着重要的角色,可能与PTC发病的分子机制有关。     

Prevalence and biological behaviour of variants of papillary thyroid carcinoma: experience at a single institute

Aims: There are many variants of papillary carcinoma, and some of these variants have been reported to show biological behaviours differing from that of conventional papillary carcinoma. In this study, we present our experience regarding the prevalence and prognoses of these variants of papillary carcinoma. Methods: H&E sections from 1521 patients who underwent initial surgery for papillary carcinoma in Kuma Hospital between 1987 and 1995 were re-reviewed and classified into conventional papillary carcinoma and various histological variants. We investigated the biological behaviours of these lesions, including prognoses. Results: Follicular, tall cell and oncocytic variants were observed in comparably high incidences: 6.6%, 3.9%, and 1.9%, respectively. Patients with tall cell variant showed significantly worse disease-free survival (DFS) and cause-specific survival (CSS) rates than those with conventional papillary carcinoma. The prognoses of patients with follicular variant did not differ from those of patients with conventional papillary carcinoma. Patients with oncocytic variant have not shown carcinoma recurrence. Among the rare variants, which accounted for less than 1%, columnar cell carcinoma showed a worse prognosis. Conclusions: Since patients with some variants show different clinical outcomes from those with conventional papillary carcinoma, classification of variants might be helpful to predict patient prognosis.     

Apaf-1在甲状腺乳头状癌中的表达及意义

目的:探讨凋亡蛋白酶活化因子1(Apaf-1)在甲状腺乳头状癌(PTC)中的m RNA与蛋白表达及其与细胞增殖的关系。方法:分别采用real-time PCR、Western blot及免疫组化法检测并比较甲状腺乳头状癌和癌旁组织中Apaf-1的m RNA及蛋白表达情况,并分析其表达水平与PTC临床病理学特征的关系;通过下调CGTHW-3细胞中Apaf-1表达量,验证Apaf-1对细胞增殖的影响。结果:在PTC组织中,Apaf-1的m RNA和蛋白表达量均显著低于癌旁组织(P 0. 05);下调Apaf-1表达增强了CGTHW-3细胞的增殖活性(P 0. 05)。结论:Apaf-1在PTC中低表达,抑制其表达可增强CGTHW-3细胞的增殖能力。Apaf-1在甲状腺乳头状癌中可能发挥抑癌作用。     

Septin 7 immunoexpression in papillary thyroid carcinoma: A preliminary study

Papillary thyroid carcinoma (PTC) is the most common type among thyroid cancers. The diagnosis of PTC may be challenging when follicular variant (FVPTC) of this disease is present due to the resemblance of nuclear properties of the classical type (CVPTC). However, making use of ancillary molecular markers in the diagnosis of PTC may help. In our study, we aimed to evaluate the SEPT7 protein expression in PTC. A total of 55 paraffin block tissue samples comprising encapsulated FVPTC (FVPTC(e), n = 25), and CVPTC (n = 15), and benign hyperfunctioning thyroid nodules (HypN, n = 15) were used in this study. Nuclear, cytoplasmic, and overall (total) SEPT7 protein expression levels were determined by using immunohistochemistry. Nuclear, cytoplasmic, and overall SEPT7 expressions (p = 0.02, p = 0.001, p = 0.002, respectively) were significantly lower in FVPTC(e) tissues when compared to HypN. In CVPTC group, nuclear expression was significantly lower (p = 0.004) while overall and cytoplasmic expressions were not changed (p > 0.05). In HypN group, highest nuclear (mean = 2.73), cytoplasmic (mean = 2.86), and overall (mean = 2.86) expression scores were detected. Significantly lower SEPT7 expression in all expressional categories in FVPTC(e) group may be a sign of different molecular signature in this type of tissue.     

Knockout of ASAP1 induces autophagy in papillary thyroid carcinoma by inhibiting the mTOR signaling pathway

Due to lymph node metastasis and infiltration, surgery for PTC (papillary thyroid carcinoma) is a high-risk treatment strategy. Our work reports for the first time that ASAP1 (ArfGAP with SH3 Domain, Ankyrin Repeat and PH Domain 1) is highly expressed in PTC and that its high expression is related to autophagy. Autophagy and ASAP1 expression in 40 PTC tissues and normal tissues were detected by immunofluorescence. We used the lentiviral CRISPR/Cas9 nickase to generate stable cell lines. The difference in autophagy levels between the ASAP1 KO group and the control group was determined by Western blot and immunofluorescence analyses. We added chloroquine (CQ) to verify that ASAP1 increased the formation of autophagosomes rather than reducing their degradation. The expression of mTOR activity-related proteins (P-P70S6K, P-MTOR) was studied by Western blotting. ASAP1 was upregulated while autophagy was downregulated in PTC tissues compared to normal tissues. Knockout of ASAP1 induced autophagy in both MDA-T32 and MDA-T85 cells. Knockout of ASAP1 attenuated the activation of the mTOR signaling pathway. Our studies demonstrated that ASAP1 is upregulated while autophagy is reduced in PTC tissues. In addition, knockout of ASAP1 induces autophagy in PTC by inhibiting the mTOR signaling pathway.     

血管内皮生长因子-C和血管内皮生长因子受体-3在侵袭性甲状腺乳头状癌中的表达及意义

目的 观察血管内皮生长因子(VEGF-C)和血管内皮生长因子受体(VEGFR3)在侵袭性甲状腺乳头状癌组织中的表达,探讨甲状腺乳头状癌细胞淋巴管转移机理.方法 用免疫组化方法检测VEGF-C和VEGFR3在人侵袭性甲状腺乳头状癌和非侵袭性甲状腺乳头状癌中的表达情况,并进行比较和分析.结果 在侵袭性和非侵袭性甲状腺乳头状癌中均可见到VEGF-C和VEGFR3阳性表达,但在侵袭性甲状腺乳头状癌组织VEGF-C (x2=4.738,P=0.030)和VEGFR3(x2=11.951,P=0.010)的表达率和表达强度均高于非侵袭性甲状腺乳头状癌.结论 VEGF-C和VEGFR3在侵袭性甲状腺乳头状癌细胞中高表达,并且可能与此肿瘤的侵袭性相关.     

A histopathological,immunohistochemical and ultrastructural study of intranuclear cytoplasmic inclusions in thyroid papillary carcinoma

Summary Intranuclear cytoplasmic inclusions (ICI) in 38 cases of thyroid papillary carcinoma were studied histopathologically, immunohistochemically, and ultrastructurally in order to examine the frequency of ICI and their relationship to both the histological structure and cytological findings in thyroid papillary carcinoma. The fine-structure and biochemical state of ICI were also studied. ICI occurred in all 38 cases. ICI occurrence ranged from one in several microscopic fields to more than ten per field. The number of ICI divided by the number of nuclei on the microscopic photographs ranged from 0.013 to 0.116. The frequency of ICI was strongly influenced by the state of nuclear chromatin and pleomorphism, but was not influenced by a pattern of papillary or follicular tumour growth. Immunohistochemically, 10-30% of ICI revealed strong thyroglobulin (Tg), which was ascertained by immunoelectron microscopy. Neither T3 nor T4 was detected in ICI (with some exceptions). Some ICI showed keratin and vimentin. PAS-positive ICI were observed. Ultrastructurally, enlarged r-ER, many Golgi vesicles and small vesicles (diameter of 300-500 nm) and sacs were observed in ICI. These findings suggested increased protein synthesis and/or protein accumulation Abundant secondary lysozomes, showing degradation of ICI, and bundles of condensed intermediate filaments were also detected. The character and genesis of ICI are discussed.     

Occult papillary carcinoma of the thyroid with pulmonary lymphangitic spread diagnosed by lung biopsy

Summary Distant metastases from occult papillary carcinoma of the thyroid, which is defined as a tumor less than 15 mm in diameter, are extremely rare. A 21-year-old patient with miliary micronodular densities in both lungs is described, in whom pulmonary lymphangitic spread of occult papillary thyroid carcinoma was diagnosed by thransthoracic lung biopsy.Abkürzungen BAL bronchoalveolar lavage - TBB transbronchial biopsy     

Evaluation of survivin expression and its prognostic value in papillary thyroid carcinoma

Overexpression of survivin, an inhibitor of apoptosis protein, has been found in a variety of human cancers, and is associated with tumor aggressiveness. In this study, we analyzed the expression of survivin in papillary thyroid carcinoma (PTC) and evaluated its clinical significance for predicting an aggressive course of disease at the time of diagnosis. Survivin expression was determined by immunohistochemistry in 104 tissue specimens of PTC, confirmed by Western blot and correlated with clinicopathological parameters. Of the tumors examined, 74 (71.15%) showed high cytoplasmic survivin expression. There was no association between high survivin expression and age, gender or tumor size. On the other hand, it was closely correlated with the presence of lymph node metastasis (P = 0.009), and there was a tendency for correlation with extrathyroidal invasion (P = 0.062). The high risk PTC group (TNM stage III–IV) was associated with high levels of survivin (P = 0.027). These results indicate that survivin is an unfavorable molecule for PTC prognosis, and that its high expression may indicate a subset of PTC patients with a more aggressive disease course. Evaluation of its expression in fine needle aspiration samples could be a useful tool for the identification of those PTC patients who require more extensive surgery, careful follow-up and therapeutic strategy.     

The p75 neurotrophin receptor is widely expressed in conventional papillary thyroid carcinoma

Papillary thyroid carcinomas (PTCs) are associated with alterations in several proto-oncogenes related with nervous system development and function, such as TrkA and RET, which are commonly rearranged in these carcinomas. The other oncogenic event recently identified in PTC is the BRAF V600E mutation. Because the role of TrkA was not completely elucidated in thyroid cancer ethiopathogenesis, we decided to study the expression of active, phosphorylated TrkA and of its coreceptor p75 neurotrophin receptor (p75 NTR) in a series of 92 PTC (37 lesions of conventional PTC, 28 of follicular variant of PTC [FVPTC], and 27 of other variants of PTC) as well as in 21 samples of normal thyroid and nonneoplastic thyroid lesions used as a controls. We observed neoexpression of p75 NTR in PTC, particularly in conventional PTC and in other variants of PTC displaying a papillary growth pattern, rather than in FVPTC. No immunoexpression of p75 NTR was observed in normal thyroid nor in nonneoplastic thyroid lesions. The cellular localization of p75 NTR immunoexpression was also significantly associated with the growth pattern of PTC, being much more frequently detected in an apical localization in PTC with papillary architecture than in PTC with a follicular or solid growth pattern. This apical localization of p75 NTR was significantly associated with the presence of BRAF V600E. No significant differences were detected between normal thyroid, nonneoplastic lesions, and PTC (or any PTC variant) regarding expression/activation of TrkA, thus suggesting that by itself and in contrast to p75 NTR, TrkA is not altered during PTC development.     

The association between the Survivin A9194G exon polymorphisms and papillary thyroid carcinoma risk in the Han Chinese population

The dysregulation of apoptosis plays a key role in carcinogenesis. This study was designed to investigate the association of apoptosis-related gene survivin A9194G single-nucleotide polymorphisms (SNPs) with papillary thyroid carcinoma (PTC) susceptibility. A case–control study of 126 patients and 198 controls was performed to investigate the association between Survivin A9194G polymorphisms and PTC susceptibility by polymerase chain reaction (PCR) following DNA sequencing methods. Moreover, the distribution of genotype frequency and the association of genotype with clinicopathologic characteristics were analyzed. We found that the survivin A9194G genotype was at a decreased risk of PTC (P = 0.003; odds ratio (OR) = 0.56). Furthermore, compared to the PTCs of the AA and AG phenotypes, the GG genotype thyroid cancers were significantly more common in younger patients and in cases of lower pathologic stages. In conclusion, the survivin (A9194G) polymorphism was found to play a protective role in the susceptibility to PTC. Nevertheless, further investigation with a larger sample size is needed to support our results.