Changes in the diagnosis of thyroid tumours in the 5th edition of the WHO classification of endocrine neoplasms.

The WHO classification of thyroid tumours enters its second half-century of development with the 5th edition. Compared to the previous 4th edition of the clas- sification, the permanent increase in information is mainly at the molecular biological level. This has changed the view of very traditional entities - the preferred name for polynodous goiter is (given the monoclonal nature of some nodules) follicular nodular thyroid disease. Some terminological relics have also been re- moved - Hürthle cells are definitively referred to as oncocytes. Follicular adenoma has a new subtype with papillary arrangement (and missing nuclear features of papillary carcinoma). In the already used NIFTP unit, subtypes smaller than 10 mm and oncocytic are newly defined. All oncocytic tumours have an arbitrarily set minimum proportion of oncocytes at 75 %. A multidisciplinary approach to the treatment of thyropathies and the stratification of therapeutic procedures according to risk brought about the introduction of grading into several nosological units of papillary, follicular, and medullary carcinomas. Grading using the number of mitoses determines their quantification at 2 mm² instead of the previously used non-uniform HPFs (high power fields of view). Clarification was made on the basis of genetic findings in a number of other, less frequent diagnoses (e.g. classification of squamous cell carcinoma among anaplastic). Among rare tumors a new category of salivary gland - type carcinomas is formulated with two representatives: mucoepidermoid and secretory carcinoma. Cribriform morular carcinoma previously classified as a variant of papillary carcinoma is newly separated on the basis of the immunological and genetic profile into the newly created category of tumors of uncertain histogenesis. This category also includes sclerosing mucoepidermoid carcinoma with eosinophilia. Microcarcino- ma as a separate entity is not included in the 5th edition. A tumor smaller than 10 mm must be characterized by the appropriate features of the corresponding category. Thyroblastoma replaces terminologically malignant teratoma from the previous classification. Part of the newly established diagnostic criteria is also applicable in FNAB diagnosis. The newly introduced grading in some nosological units can exceptionally change the diagnosis (NIFTP/EFVPTC/non-invasive HG FVPTC), but above all it will affect the choice of therapeutic procedures.

Histology-based and cytology-based needle sampling for targeted next-generation sequencing in the indeterminate thyroid tumors.

PURPOSE: To establish the optimal and minimally invasive diagnostic approach for targeted next-generation sequencing (NGS) in the indeterminate thyroid tumors. METHODS: The patients with indeterminate thyroid tumors were prospectively recruited and analyzed in a single tertiary medical center. We performed FNA and core needle biopsy (CNB) at the surgical specimens to confirm the quality of each sampling procedure. Cytological diagnosis by FNA, histological diagnosis by CNB and confirmed diagnosis by final surgery were compared to demonstrate the agreement among these approaches for the indeterminate thyroid tumors. The quality of the samples from FNA and CNB was evaluated, respectively to determine the optimal approach for targeted NGS. Finally, we performed ultrasound-guided CNB and FNA (US-CNB and US-FNA) on one case to confirm the clinical feasibility of being a pre-operative minimally invasive diagnostic approach. RESULTS: A total of 6 female patients (average age: 50.83 ± 15.18 years) with indeterminate thyroid tumors (average size: 1.79 ± 0.91 cm) were recruited for further analyses. The pathological diagnoses could be obtained by CNB in the first five cases, and the sample quality of CNB for targeted NGS was better than that of FNA, even after 10X dilution. The gene mutations associated with thyroid malignancy could be detected by NGS. In the case treated with US-CNB, the pathological and targeted NGS results were successfully obtained, which suggested the possibility of thyroid malignancy to facilitate immediate decision of subsequent treatment. CONCLUSION: CNB could serve as a minimally invasive diagnostic approach in the indeterminate thyroid tumors by providing pathological diagnoses and qualified samples for detection of mutated genes, which facilitates appropriate and immediate management.

Ultrasonographic Findings and Prognosis of Metastases to the Thyroid Gland.

Metastases to the thyroid gland (MTT) are uncommon in clinical practice. The ultrasound (US) features are easily confused with primary thyroid malignancy, Hashimoto's thyroiditis, and other thyroid diseases. Therefore, this study aimed to assess the role of US and analysis of prognosis of MTT. A total of 45 patients with MTT in the database between July 2009 and February 2022 at the Fujian Cancer Hospital were reviewed. US examinations were performed only on 20 patients, who were finally included in our study. Among the 20 patients, nine were male, and eleven were female. According to US characteristics, metastases to the thyroid gland were divided into nodular and diffuse types (17 and 3 cases, respectively). Three lesions (17.6%) had circumscribed margins, and 14 (82.4%) were uncircumscribed. Three lesions (17.6%) were regular in shape, and 14 (82.4%) were irregular. Nine metastases (52.9%) were a taller-than-wide shape, and eight (47.1%) were not a taller-than-wide shape. Ten lesions (58.8%) had rich vascularity, and seven (41.2%) had absence/not rich vascularity. The mean overall survival (OS) from the time of MTT diagnosis was 22 months (95% confidence interval: 5.95-38.05). The 1-, 3-, and 5-year OS after metastasis was 68.1%, 25.5%, and 17%, respectively. The prognosis of MTT was poor, which is closely related to the characteristics of the primary tumor and metastatic disease. The US findings and US-guided core needle biopsy may be useful in diagnosing MTT in patients with a history of the malignant tumors.

Expanding the Spectrum of BRAF Non-V600E Mutations in Thyroid Nodules: Evidence-Based Data from a Tertiary Referral Centre.

The BRAF p.V600E mutation represents the most specific marker for papillary thyroid carcinoma and is potentially related to aggressive behavior and persistent disease. BRAF alterations other than the p.V600E are less common in thyroid carcinoma and represent an alternative mechanism of BRAF activation with unclear clinical significance. The study aims to describe the frequency and clinicopathologic characteristics of BRAF non-V600E mutations in a large cohort (1654 samples) of thyroid lesions characterized by next-generation sequencing. BRAF mutations have been found in 20.3% (337/1654) of thyroid nodules, including classic (p.V600E) mutation in 19.2% (317/1654) of samples and non-V600E variants in 1.1% of cases (19/1654). BRAF non-V600E alterations include 5 cases harboring p.K601E, 2 harboring p.V600K substitutions, 2 with a p.K601G variant, and 10 cases with other BRAF non-V600E alterations. BRAF non-V600E mutations have been reported in one case of follicular adenoma, three cases of conventional papillary thyroid carcinoma, eight cases of follicular variant of papillary carcinomas, one case of columnar cell variant papillary thyroid carcinoma, one case of oncocytic follicular carcinoma, and two bone metastasis of follicular thyroid carcinoma. We confirm that BRAF non-V600E mutations are uncommon and typically found in indolent follicular-patterned tumors. Indeed, we show that BRAF non-V600E mutations can be found in tumors with metastatic potential. However, in both aggressive cases, the BRAF mutations were concomitant with other molecular alterations, such as TERT promoter mutation.

Pathological diagnosis of general rules for the description of thyroid cancer by Japanese Society of Thyroid Pathology and Japan Association of Endocrine Surgery.

The Japanese Society of Thyroid Pathology and the Japan Association of Endocrine Surgeons developed the eighth edition of the General Rules for the Description of Thyroid Cancer (GRDTC) in December 2019. This article describes the pathological diagnosis of the GRDTC, which has been improved through repeated revisions based on the experience of Japanese pathologists and translated into English to introduce the Japanese diagnostic standard to foreign countries. In this edition of the GRDTC, the histopathological classification and descriptions differ in some respects from those of the fourth edition of the World Health Organization (WHO) classification as revised in 2017. For example, the GRDTC does not adopt the concept of borderline lesions (FT-UMP, WDT-UMP, and NIFTP) of the WHO, taking into consideration the popular histological criteria accepted by Japanese pathologists. The cytological reporting system of the GRDTC was partly modified from the Bethesda system in 2015. It has an additional cyst fluid category separated from the unsatisfactory category that has been demonstrated to be useful in Japan. This translated edition makes it easy to submit Japanese clinicopathological studies of thyroid tumors in an international journal. We also wish to contribute to the improvement, standardization, and globalization of the pathological diagnosis of thyroid tumors.

Oncocytic nodular hyperplasia of the thyroid.

Nodular hyperplasia of the thyroid is a process whereby the gland experiences growth by nodular expansion of thyroid parenchyma. We have encountered 45 patients in whom the process was caused by the growth of well-defined and sharply circumscribed but unencapsulated nodules composed of oncocytic thyroid follicular cells. The lesions arose in 39 women and 6 men, aged 25-69 years (mean = 50.3 years). The surrounding thyroid parenchyma showed features of chronic lymphocytic thyroiditis. The nodules varied from microscopic to 5 cm and appeared to compress the surrounding thyroid parenchyma. Most of the lesions lacked a well-defined capsule. In 26 tumors, the nodules displayed a predominantly follicular pattern of growth; in 8 cases there were admixtures of follicular and trabecular patterns with focal solid areas devoid of follicles. Clinical follow-up in 39 patients ranging from 7 to 22 years (median = 16 years) showed no evidence of recurrence, metastasis, or malignant transformation. One patient died of unknown causes 15 years after the diagnosis, and another patient died 4 years after diagnosis from metastatic colonic adenocarcinoma. Oncocytic nodular hyperplasia is a benign process associated with chronic lymphocytic thyroiditis that should be distinguished from benign and malignant oncocytic (Hurthle cell) tumors of the thyroid.

Identification of circulating biomarkers for differentiating patients with papillary thyroid cancers from benign thyroid tumors.

BACKGROUND: This study aimed to identify the potential circulating biomarkers of protein, mRNAs, and long non-coding RNAs (lncRNAs) to differentiate the papillary thyroid cancers from benign thyroid tumors. METHODS: The study population of 100 patients was classified into identification (10 patients with papillary thyroid cancers and 10 patients with benign thyroid tumors) and validation groups (45 patients with papillary thyroid cancers and 35 patients with benign thyroid tumors). The Sengenics Immunome Protein Array-combined data mining approach using the Open Targets Platform was used to identify the putative protein biomarkers, and their expression validated using the enzyme-linked immunosorbent assay. Next-generation sequencing by Illumina HiSeq was used for the detection of dysregulated mRNAs and lncRNAs. The website Timer v2.0 helped identify the putative mRNA biomarkers, which were significantly over-expressed in papillary thyroid cancers than in adjacent normal thyroid tissue. The mRNA and lncRNA biomarker expression was validated by a real-time polymerase chain reaction. RESULTS: Although putative protein and mRNA biomarkers have been identified, their serum expression could not be confirmed in the validation cohorts. In addition, seven lncRNAs (TCONS_00516490, TCONS_00336559, TCONS_00311568, TCONS_00321917, TCONS_00336522, TCONS_00282483, and TCONS_00494326) were identified and validated as significantly downregulated in patients with papillary thyroid cancers compared to those with benign thyroid tumors. These seven lncRNAs showed moderate accuracy based on the area under the curve (AUC = 0.736) of receiver operating characteristic in predicting the occurrence of papillary thyroid cancers. CONCLUSIONS: We identified seven downregulated circulating lncRNAs with the potential for predicting the occurrence of papillary thyroid cancers.

Molecular Chaperones and Thyroid Cancer.

Thyroid cancers are the most common of the endocrine system malignancies and progress must be made in the areas of differential diagnosis and treatment to improve patient management. Advances in the understanding of carcinogenic mechanisms have occurred in various fronts, including studies of the chaperone system (CS). Components of the CS are found to be quantitatively increased or decreased, and some correlations have been established between the quantitative changes and tumor type, prognosis, and response to treatment. These correlations provide the basis for identifying distinctive patterns useful in differential diagnosis and for planning experiments aiming at elucidating the role of the CS in tumorigenesis. Here, we discuss studies of the CS components in various thyroid cancers (TC). The chaperones belonging to the families of the small heat-shock proteins Hsp70 and Hsp90 and the chaperonin of Group I, Hsp60, have been quantified mostly by immunohistochemistry and Western blot in tumor and normal control tissues and in extracellular vesicles. Distinctive differences were revealed between the various thyroid tumor types. The most frequent finding was an increase in the chaperones, which can be attributed to the augmented need for chaperones the tumor cells have because of their accelerated metabolism, growth, and division rate. Thus, chaperones help the tumor cell rather than protect the patient, exemplifying chaperonopathies by mistake or collaborationism. This highlights the need for research on chaperonotherapy, namely the development of means to eliminate/inhibit pathogenic chaperones.

[Szpiczak plazmocytowy tarczycy - opis przypadku]. / Extramedullary plasmacytoma of the thyroid gland ­ a case report.

Extramedullary plasmacytoma (EMP) is the localized plasma cell neoplasm, that arise in tissues other than bone. The upper respiratory tract and the oral cavity are the most common sites for EMP location. EMPs of the thyroid gland are extremely rare and thus little is known about their behavior compared to other EMPs. CASE REPORT: 68-year-old female patient was admitted to the Department of General, Gastroenterological and Endocrine Surgery due to suspicion of neoplastic proliferation of unknown character within the thyroid gland. Computed tomography (CT) of the neck and chest showed tumor modeling adjacent anatomical structures. Cytological presentation obtained by fine needle aspiration biopsy was classified as category V according to the Bethesda system ("suspicious for malignancy"). The recognition of the lymphoma was suggested. The histopathological examination result of the specimens obtained from surgical biopsy was ambiguous. The patient was transferred to the Neurosurgical Department to continue the diagnostic process due to a presence of tumor within Th5 vertebral body. Percutaneous biopsy and magnetic resonance imaging (MRI) was performed, revealing metastatic character of the lesion and presence of plasma cells. After transferring patient back to surgical ward thyroidectomy was performed. Postoperative histopathological and immunohistochemisty analysis revealed EMP with highly immature morphology. Afterwards patient was admitted to Hematology Clinic in order to establish an adjuvant therapy. CONCLUSIONS: EMP is a very rare form of the primary thyroid malignancy, what makes it difficult to recognize. However, in the differential diagnosis of the thyroid tumors, EMP should be always considered.

Molecular evaluation of BRAF gene mutation in thyroid tumors: Significant association with papillary tumors and extra thyroidal extension indicating its role as a biomarker of aggressive disease.

BACKGROUND: Somatic mutation of the BRAF gene is one to be the most commonly known genetic change in thyroid tumors especially papillary thyroid cancers. The T1799A activating point mutation is detected in >98% of the thyroid tumors, and result in substitution of amino acid valine at position 600 to glutamic acid. METHOD: In this study, we evaluated BRAF mutation in 95 Indian thyroid tumors by pyrosequencing assay. RESULTS: Overall, 36 cases (38%) showed presence of BRAF V600E mutation, while none of the cases showed V600 K mutation. BRAF mutation was found predominantly in female patients in comparison to males (38.4% vs. 36.4%, p = .86). Likewise, smaller sized tumors (≤2.0 cm) showed increased frequency of BRAF mutation as compared to larger sized tumors which were greater than equal to 2 cm (46% vs. 34.4%, p = .64). Furthermore, the frequency of BRAF mutations was significantly higher in conventional PTC tumor type in comparison to non-conventional and other than PTC tumor type (56% vs. 35% vs. 4%, p = .0007). Notably, a significant correlation between presence of BRAF mutation and extra-thyroidal extension was noted. Nevertheless, presence of BRAF mutation was neither associated with capsular/vascular invasion, nor with tumor necrosis. CONCLUSIONS: Pyrosequencing assay was found to be highly sensitive and accurate method for detecting BRAF point mutations. The frequency and distribution pattern of BRAF mutations is similar to global reports. Furthermore, association of BRAF mutation with extra thyroidal extension indicates its aggressive nature and thus can provide insights into the progression of thyroid tumors from less aggressive to poorly differentiated subtype.

Human relevance of follicular thyroid tumors in rodents caused by non-genotoxic substances.

Chronic stimulation of the thyroid gland of rodents by TSH leads to thyroid follicular hyperplasia and subsequently to thyroid follicular adenomas and carcinomas. However, the interpretations of rodent thyroid tumors are contradictory. The U.S. Food and Drug Administration (FDA) concluded that findings with drugs that lead to increased levels of thyroid-stimulating hormone (TSH) in rats are not relevant to humans, whereas the U.S. Environmental Protection Agency (US EPA) concluded that chemicals that produce rodent thyroid tumors may pose a carcinogenic hazard for humans although the thyroid of rodents appears to be more sensitive to a carcinogenic stimulus than that of humans. Meanwhile, based on the CLP Criteria of the European Chemicals Agency (ECHA), rodent thyroid tumors caused by the induction of uridine-diphosphate-glucuronosyl transferases (UDGT) were assessed as not relevant to humans. To clarify these discrepant positions, the function and regulation of the thyroid gland are described and the types of thyroid tumors and the causes of their development in humans and animals are examined. Based on these data and the evidence that so far, except radiation, no chemical is known to increase the incidence of thyroid tumors in humans, it is concluded that rodent thyroid tumors resulting from continuous stimulation of the thyroid gland by increased TSH levels are not relevant to humans. Consequently, compounds that induce such tumors do not warrant classification as carcinogenic.

Expression of Antioxidant Molecules and Heat Shock Protein 27 in Thyroid Tumors.

Oxidative stress-induced DNA damage is a known causing factor for many types of tumors, but information on the role of oxidants and antioxidants in thyroid tumors is limited. The aim of this study was to determine antioxidant levels in thyroid tumors. In this study, tumor and its matched non-tumor thyroid tissue samples were obtained from 53 patients with thyroid tumors. The levels of manganese superoxide dismutase (MnSOD), thioredoxin reductase 2 (TXNRD2), glutathione (GSH), glutathione peroxidase (Gpx), catalase (CAT), and 27 kd heat-shock protein (hsp27) were determined in both thyroid tissue samples and cultured thyroid cells by immunohistochemical staining and western blot. Hydrogen peroxide (H2 O2 ) was used to generate oxidant stress in the cell culture experiments. We found that the levels of MnSOD, TXNRD2, GSH, Gpx, and Hsp27 were increased in both malignant and benign tumors, while the level of CAT was decreased. To verify the results of the tissue study, we treated cultured thyroid cells with H2 O2 and found the same pattern of antioxidant changes. Hsp27 was also increased after H2 O2 treatment. The expression of hsp27 was upregulated by 8.24-, 6.96-, and 3.09-fold in thyroid cancer, follicular adenoma, multinodular goiter, respectively. Collectively, our study demonstrated that the levels of hsp27 together with MnSOD, TXNRD2, GSH, and Gpx were significantly upregulated by H2 O2 in thyroid tumors. The increase of these antioxidants is observed in both malignant and benign tumors, particularly in the former. The upregulation of antioxidants is likely a protective mechanism of tumor cells to maintain their survival and growth. J. Cell. Biochem. 117: 2473-2481, 2016. © 2016 Wiley Periodicals, Inc.

Multi-institutional validation of a novel textural analysis tool for preoperative stratification of suspected thyroid tumors on diffusion-weighted MRI.

PURPOSE: Ultrasound-guided fine needle aspirate cytology fails to diagnose many malignant thyroid nodules; consequently, patients may undergo diagnostic lobectomy. This study assessed whether textural analysis (TA) could noninvasively stratify thyroid nodules accurately using diffusion-weighted MRI (DW-MRI). METHODS: This multi-institutional study examined 3T DW-MRI images obtained with spin echo echo planar imaging sequences. The training data set included 26 patients from Cambridge, United Kingdom, and the test data set included 18 thyroid cancer patients from Memorial Sloan Kettering Cancer Center (New York, New York, USA). Apparent diffusion coefficients (ADCs) were compared over regions of interest (ROIs) defined on thyroid nodules. TA, linear discriminant analysis (LDA), and feature reduction were performed using the 21 MaZda-generated texture parameters that best distinguished benign and malignant ROIs. RESULTS: Training data set mean ADC values were significantly different for benign and malignant nodules (P = 0.02) with a sensitivity and specificity of 70% and 63%, respectively, and a receiver operator characteristic (ROC) area under the curve (AUC) of 0.73. The LDA model of the top 21 textural features correctly classified 89/94 DW-MRI ROIs with 92% sensitivity, 96% specificity, and an AUC of 0.97. This algorithm correctly classified 16/18 (89%) patients in the independently obtained test set of thyroid DW-MRI scans. CONCLUSION: TA classifies thyroid nodules with high sensitivity and specificity on multi-institutional DW-MRI data sets. This method requires further validation in a larger prospective study. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance.

Toxicity and carcinogenicity studies of Ginkgo biloba extract in rat and mouse: liver, thyroid, and nose are targets.

Ginkgo biloba extract (GBE) is a popular herbal supplement that is used to improve circulation and brain function. In spite of widespread human exposure to relatively high doses over potentially long periods of time, there is a paucity of data from animal studies regarding the toxicity and carcinogenicity associated with GBE. In order to fill this knowledge gap, 3-month and 2-year toxicity and carcinogenicity studies with GBE administered by oral gavage to B6C3F1/N mice and F344/N rats were performed as part of the National Toxicology Program's Dietary Supplements and Herbal Medicines Initiative. The targets of GBE treatment were the liver, thyroid, and nose. These targets were consistent across exposure period, sex, and species, albeit with varying degrees of effect observed among studies. Key findings included a notably high incidence of hepatoblastomas in male and female mice and evidence of carcinogenic potential in the thyroid gland of both mice and rats. Various nonneoplastic lesions were observed beyond control levels in the liver, thyroid gland, and nose of rats and mice administered GBE. Although these results cannot be directly extrapolated to humans, the findings fill an important data gap in assessing risk associated with GBE use.

Surgical management of anterior mediastinal tumors of thyroid origin: a comprehensive analysis of approaches, techniques, and outcomes.

BACKGROUND: This manuscript aims to describe the symptoms, demographics, surgical approaches and techniques, the volume of surgical interventions, histological results, intra- and postoperative complications, and postoperative results in patients with anterior mediastinal tumors of thyroid origin (AMTTO). METHODS: Twenty patients with AMTTO were operated between 2017 and 2021. Fifteen were women and 5 were men. The mean age was 66.8 years. RESULTS: The most common histology was nodular micro- and macrofollicular goiter (15/20, 75%). Kocher cervicotomy (65%) was the preferred approach. Total thyroidectomy was performed in 95% of patients. Intraoperative complications were identified in 25% (5/20), and in 2 patients a tracheostomy was required. Early postoperative complications were established in 65% and the most common was unilateral transient recurrent nerve paresis or paralysis and dysphonia (25%). CONCLUSIONS: Commonly resection of AMTTO is a challenge due to its complexities associated with high-risk cases, emphasizing the need for experienced centers in managing such cases.

Seven years of Non-invasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP): Rate of Acceptance and Variation of Diagnostic Approaches Across Different Continents.

CONTEXT: Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was introduced as a new entity replacing the diagnosis of noninvasive encapsulated follicular variant of papillary thyroid carcinoma (PTC). Significant variability in the incidence of NIFTP diagnosed in different world regions has been reported. OBJECTIVE: To investigate the rate of adoption of NIFTP, change in practice patterns, and uniformity in applying diagnostic criteria among pathologists practicing in different regions. METHODS: Two surveys distributed to pathologists of the International Endocrine Pathology Discussion Group with multiple-choice questions on NIFTP adoption into pathology practice and whole slide images of 5 tumors to collect information on nuclear score and diagnosis. Forty-eight endocrine pathologists, including 24 from North America, 8 from Europe, and 16 from Asia/Oceania completed the first survey and 38 the second survey. RESULTS: A 94% adoption rate of NIFTP by the pathologists was found. Yet, the frequency of rendering NIFTP diagnosis was significantly higher in North America than in other regions (P = .009). While the highest concordance was found in diagnosing lesions with mildly or well-developed PTC-like nuclei, there was significant variability in nuclear scoring and diagnosing NIFTP for tumors with moderate nuclear changes (nuclear score 2) (case 2, P < .05). Pathologists practicing in North America and Europe showed a tendency for lower thresholds for PTC-like nuclei and NIFTP than those practicing in Asia/Oceania. CONCLUSION: Despite a high adoption rate of NIFTP across geographic regions, NIFTP is diagnosed more often by pathologists in North America. Significant differences remain in diagnosing intermediate PTC-like nuclei and respectively NIFTP, with more conservative nuclear scoring in Asia/Oceania, which may explain the geographic differences in NIFTP incidence.

A synchronous presentation of thyroid follicular carcinoma-like renal tumor and papillary vesicular thyroid tumors: About an exceptional case and review of the literature.

INTRODUCTION: Thyroid follicular renal cell carcinoma is a special type of renal cell carcinoma newly recognized in recent years. The data is not mature due to the rarity of cases. The association of vesicular papillary tumors of the thyroid is exceptional, and this is the first publication describing such an association in the literature. CASE PRESENTATION: We present the case of a patient who consulted for a goiter. The definitive pathological examination of the specimen of the thyroidectomy showed papillary vesicular thyroid tumors. A month later, she presented with total hematuria; the CT scan revealed a left renal mass; the patient underwent a partial nephrectomy; and the definitive pathological examination of the specimen showed a thyroid follicular carcinoma-like renal tumor. DISCUSSION: Thyroid-type follicular cell renal cell carcinomas are currently recognized as a distinct entity whose histological appearance is reminiscent of thyroid vesicular lesions. There are currently around 39 cases in the literature, but no concomitant thyroid localization has been observed. This finding cannot be verified in the absence of a systematic histological study of the thyroid gland. Our case invites discussion of other thyroid investigation modalities, in particular the value of thyroid biopsy versus cytopuncture, which is often inconclusive in this type of situation. CONCLUSION: At present, understanding of TFCLRT is still very limited. Even more so, their association with a thyroid tumor is exceptional in the literature. We need to increase the number of cases and conduct in-depth investigations with longer follow-up periods to better understand the situation.

The Role of 5-Hydroxymethylcytosine as a Potential Epigenetic Biomarker in a Large Series of Thyroid Neoplasms.

Cytosine modifications at the 5-carbon position play a critical role in gene expression regulation and have been implicated in cancer development. 5-Hydroxymethylcytosine (5hmC), arising from 5-methylcytosine (5-mC) oxidation, has shown promise as a potential malignancy marker due to its depletion in various human cancers. However, its significance in thyroid tumors remains underexplored, primarily due to limited data. In our study, we evaluated 5hmC expression levels by immunohistochemistry in a cohort of 318 thyroid tumors. Our analysis revealed significant correlations between 5hmC staining extension scores and nodule size, vascular invasion, and oncocytic morphology. Nuclear 5hmC staining intensity demonstrated associations with focality, capsule status, extrathyroidal extension, vascular invasion, and oncocytic morphology. Follicular/oncocytic adenomas exhibited higher 5hmC expression than uncertain malignant potential (UMP) or noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), as well as malignant neoplasms, including papillary thyroid carcinomas (PTCs), oncocytic carcinomas (OCAs), follicular thyroid carcinomas (FTCs), and invasive encapsulated follicular variants of PTC (IEFV-PTC). TERT promoter mutation cases showed notably lower values for the 5hmC expression, while RAS (H, N, or K) mutations, particularly HRAS mutations, were associated with higher 5hmC expression. Additionally, we identified, for the first time, a significant link between 5hmC expression and oncocytic morphology. However, despite the merits of these discoveries, we acknowledge that 5hmC currently cannot segregate minimally invasive from widely invasive tumors, although 5hmC levels were lower in wi-FPTCs. Further research is needed to explore the potential clinical implications of 5hmC in thyroid tumors.

Molecular pathology of endocrine gland tumors: genetic alterations and clinicopathologic relevance.

Tumors of the endocrine glands are common. Knowledge of their molecular pathology has greatly advanced in the recent past. This review covers the main molecular alterations of tumors of the anterior pituitary, thyroid and parathyroid glands, adrenal cortex, and adrenal medulla and paraganglia. All endocrine gland tumors enjoy a robust correlation between genotype and phenotype. High-throughput molecular analysis demonstrates that endocrine gland tumors can be grouped into molecular groups that are relevant from both pathologic and clinical point of views. In this review, genetic alterations have been discussed and tabulated with respect to their molecular pathogenetic role and clinicopathologic implications, addressing the use of molecular biomarkers for the purpose of diagnosis and prognosis and predicting response to molecular therapy. Hereditary conditions that play a key role in determining predisposition to many types of endocrine tumors are also discussed.

Analyzing the correlation between low proportion of hobnail features in papillary thyroid carcinoma and clinical aggressiveness risk.

PURPOSE: Hobnail features may enhance the clinical aggressiveness of papillary thyroid carcinoma (PTC). However, whether a low proportion (<30%) of these features contributes to increased PTC aggressiveness remains unclear. This study investigated whether PTC cases with a low proportion hobnail features (<30%) exhibit clinical invasiveness and pathological features of aggressiveness. METHODS: Pathological specimens from patients with postoperatively diagnosed PTC were retrospectively analyzed. Among them, 29 PTC cases with a low proportion of hobnail features (<30%) were compared with 173 consecutive classical PTC (cPTC) cases. Data regarding age at presentation, sex, tumor size, number of tumors, and histological characteristics were obtained by reviewing electronic medical records. Postoperative information was obtained during follow-up visits and telephone interviews. RESULTS: Twenty-nine patients with PTC with a low proportion of hobnail features (<30%) were identified, exhibiting a median age of 34 years. At a median follow-up of 31 (IQR, 23-37) months, two patients had recurrent disease in the PTC with a low proportion of hobnail features (<30%) group, whereas there was no recurrence in the cPTC group. No distant metastasis and postoperative mortality were observed in either group. Compared with the cPTC group, patients with PTC and a low proportion of hobnail features exhibited larger tumor volumes and higher susceptibility to capsular invasion and lymph node metastasis. Tumor size and hobnail features emerged as independent risk factors for lymph node metastasis. CONCLUSION: PTC with a low proportion hobnail features (<30%) and larger tumor volumes are associated with the occurrence of lymph node metastasis. A low proportion of hobnail features (<30%) in PTC may heighten invasiveness, elevating the risk of recurrence.