Clinical, Histopathological, and Radiological Profile of Patients Presenting With Thyroid Malignancies Among the Kerala Population

BACKGROUND AND OBJECTIVE

Thyroid cancer, though relatively uncommon among all cancer types, stands as the primary form of endocrine tumor. Over the last 20 years, there has been a significant uptick in its occurrence. Papillary thyroid carcinoma (PTC), which is well-differentiated, emerges as the dominant subtype, in regions where iodine levels are deemed adequate. The study aimed to study the clinicopathological profile of patients diagnosed with thyroid malignancies at the Muslim Educational Society (MES) Medical College Perinthalmanna.

MATERIALS AND METHODS

This is a retrospective study undertaken at the MES Medical College by the Department of General Surgery and Endocrine Surgery. The study focuses on patients who have been diagnosed with thyroid cancer through a biopsy. Case sheets of all those patients diagnosed with thyroid malignancy were referred from the Medical Records Library to collect the relevant medical and sociodemographic data. This data was entered in the proforma, which was transferred to the Excel sheet and processed in IBM SPSS Statistics for Windows, Version 20 (Released 2011; IBM Corp., Armonk, New York, United States).

RESULTS

The study included predominantly middle-aged individuals (40-60 years), with 22 (55%) falling within this age range, followed by 14 (35%) aged between 20 and 40 years, and only four (10%) above 60 years. Female patients constituted 82.5% of the study group. Most cases presented with swelling lasting less than six months 23 (57.5%), while only four (10%) had swelling lasting more than five years. Compression symptoms were rare, with only three (7.5%) experiencing dysphagia or dyspnea. Pain was reported in two (5%) of the cases. Hypothyroidism, toxic manifestations, or hoarseness were observed in one (2.5%) of the patients. Regarding swelling characteristics, most were greater than 4 cm in size (29, 72%) and firm in consistency (25, 62.5%). Nodular surfaces were present in 19 (47.5%) of the cases, while 38 (95%) of the swellings were mobile. Palpable lymph nodes were noted in 13 (32.5%) of cases. Radiologically, hypoechoic lesions were observed in 26 (65%) of cases, with microcalcification in 29 (72.5%) and peripheral vascularity in 31 (77.5%). Papillary carcinoma was the most common histological type (34, 85%), with medullary and follicular carcinomas accounting for five (12.5%) and one (2.5%), respectively. An association was found between the duration of swelling and histological type (p = 0.05) and between the mobility of swelling and histological type (p < 0.05). However, no significant associations were observed between imaging findings and histological type (p > 0.05). The gender distribution did not show a statistically significant association with histological type.

CONCLUSION

The findings of the study revealed a statistically insignificant association between age, gender, clinical features, and the histological type of thyroid malignancy. Additionally, there was no statistically significant association between the histological type of thyroid malignancy and the size or type of surface or consistency of thyroid swelling or ultrasonographic findings of the swelling like echogenicity, microcalcification, increased peripheral vascularity, or loss of peripheral halo.

Utility of the Growth Differentiation Factor-15 in the Differential Diagnosis of Follicular-Patterned Lesions of the Thyroid on Cytopathologic and Histopathologic Samples

Background Follicular-patterned lesions are a major gray zone in thyroid cytopathology. The recently introduced 2022 World Health Organization (WHO) classification emphasizes the importance of genetic alterations in thyroid neoplasms with the introduction of certain newer terminologies that are expected to cause remarkable changes in cytopathologic and histopathologic reporting. Although molecular assays such as the Afirma gene expression classifier and the ThyroSeq are already in use, there has been an ongoing search for further reliable molecular markers. The growth differentiation factor-15 (GDF-15) is one among them. This study aimed to determine the diagnostic utility of GDF-15 mRNA expression in frozen tissue and fine-needle aspiration (FNA) samples from follicular-patterned thyroid lesions and neoplasms. Methodology The real-time quantitative polymerase chain reaction was performed on 75 frozen tissue and FNA samples each from 19 cases of follicular thyroid hyperplasia (FTH), 10 nodular goiters (NGs), 17 follicular thyroid adenomas (FTAs), eight follicular thyroid carcinomas (FTCs), 12 follicular variant of papillary thyroid carcinomas (FVPTCs), and nine classic papillary thyroid carcinomas (CPTCs) that were diagnosed according to the 2017 WHO classification of thyroid neoplasms. The GDF-15 mRNA expression in all these cases was assessed and compared with the control thyroid tissue samples. One-way analysis of variance and the Kruskal-Wallis test were performed using GraphPad Prism 8 software to determine the significance of differences in the GDF-15 mRNA levels among various thyroid lesions. Results A higher GDF-15 mRNA expression was noted in the malignant thyroid neoplasms including FTC, FVPTC, and CPTC in comparison to FTA, with a fold change between the malignant and benign groups being more than 244.18 times. A difference in the fold change was noted between FTH and FTA with an increase in GDF-15 mRNA level in the latter, which was statistically not significant. Conclusions The fact that GDF-15 mRNA was studied both on fine-needle aspiration cytologic and the frozen tissue material and that the majority of the lesions studied were follicular-patterned establishes the GDF-15 as a potential marker not only for diagnosing malignant thyroid neoplasms of the follicular epithelium but also in distinguishing benign and malignant follicular-patterned neoplasms of the thyroid.

Hurthle cell carcinoma: a rare variant of thyroid malignancy - a case report

Oncocytic/Hurthle cell neoplasm is a rare form of thyroid malignancies, derived from follicular epithelium, presenting with a wide variety having either presenting with features of thyrotoxicosis or no any associated symptoms.

Case presentation

The authors present a case of a 49-year-old female with a known case of chronic obstructive pulmonary disease and hypertension who presented to our hospital with anterior neck swelling for 4 months that has gradually increased over the time. Physical examination, laboratory test, various radiological imaging, and cytological study led to the diagnosis of Hurthle cell neoplasm. With prompt diagnosis, she was admitted and surgery was done that include right hemithyroidectomy. Though it is a rare type of thyroid malignancy, early diagnosis and proper treatment has shown a very good prognosis.

Clinical discussion

Hurthle cell carcinoma initially presents with a single, painless palpable mass in the thyroid with pressure symptoms in advanced cases including dysphagia, dyspnea, and hoarseness. Pain, rapid growth, or significant compressive symptoms are suggestive of an invasive one.

Conclusion

This case highlights on rarity of disease, presentation, and availability of treatment modality.

Multi-Omics and Management of Follicular Carcinoma of the Thyroid

Follicular thyroid carcinoma (FTC) is the second most common cancer of the thyroid gland, accounting for up to 20% of all primary malignant tumors in iodine-replete areas. The diagnostic work-up, staging, risk stratification, management, and follow-up strategies in patients who have FTC are modeled after those of papillary thyroid carcinoma (PTC), even though FTC is more aggressive. FTC has a greater propensity for haematogenous metastasis than PTC. Furthermore, FTC is a phenotypically and genotypically heterogeneous disease. The diagnosis and identification of markers of an aggressive FTC depend on the expertise and thoroughness of pathologists during histopathological analysis. An untreated or metastatic FTC is likely to de-differentiate and become poorly differentiated or undifferentiated and resistant to standard treatment. While thyroid lobectomy is adequate for the treatment of selected patients who have low-risk FTC, it is not advisable for patients whose tumor is larger than 4 cm in diameter or has extensive extra-thyroidal extension. Lobectomy is also not adequate for tumors that have aggressive mutations. Although the prognosis for over 80% of PTC and FTC is good, nearly 20% of the tumors behave aggressively. The introduction of radiomics, pathomics, genomics, transcriptomics, metabolomics, and liquid biopsy have led to improvements in the understanding of tumorigenesis, progression, treatment response, and prognostication of thyroid cancer. The article reviews the challenges that are encountered during the diagnostic work-up, staging, risk stratification, management, and follow-up of patients who have FTC. How the application of multi-omics can strengthen decision-making during the management of follicular carcinoma is also discussed.

Frequency and Type of Thyroid Carcinoma in Patients With Multinodular Goiter

Background This study aimed to investigate the incidence and subtype of thyroid cancer in multinodular goitre (MNG) patients who underwent total thyroidectomy. Methodology A cross-sectional study was conducted at the Khyber Teaching Hospital, screening 207 MNG patients who received complete thyroidectomies between July and December 2022. The senior consultant diagnosed thyroid cancer based on a complete history, physical examination, and laboratory and radiological studies. Ultrasound-guided fine-needle aspiration cytology was performed by a senior consultant radiologist. Bethesda categories for all lesions were recorded. All patients underwent thyroidectomy, and the diagnosis of thyroid cancer was confirmed on histopathology.  Results A total of 207 patients were included in the study, with a mean age of 45.55 ± 8.75 years. Out of 207 patients, 24 (11.59%) were diagnosed with thyroid cancer. Out of 62 male patients, 15 (7.25%) had thyroid cancer. Out of 145 female patients, only nine had cancer (p < 0.001). Nine patients with thyroid cancer had a body mass index (BMI) below 18, compared to only five patients with a BMI of more than 30 kg/m². The difference in age distribution was not significant in our study (p = 0.102).  Conclusion  In conclusion, our study sheds light on the frequency and potential risk factors associated with thyroid cancer in patients with multinodular goiter. Our findings reveal that papillary thyroid carcinoma is the most commonly observed form of thyroid cancer in this patient population, with around 12 percent of patients diagnosed with thyroid cancer. Notably, our study highlights that male patients and those with a lower BMI may have a greater risk of developing thyroid cancer in the context of multinodular goiter. The findings of this study have important implications for the care and follow-up of MNG patients who receive total thyroidectomy. Further research is needed to investigate the type and prognosis of thyroid cancer in patients with MNG.

Beware the recurrent 'benign' multinodular goitre

BACKGROUND

The diagnosis of follicular carcinoma is often difficult to make on pathological analysis, as the histological distinction from follicular adenoma rests solely on the presence of capsular or vascular invasion. Even on retrospective review of the histopathology after the disease biology has declared itself as malignant, the pathological diagnosis of malignancy may not be possible to make.

METHODS

We report three cases in which patients were initially diagnosed with benign follicular lesions, but re-presented with locally recurrent disease and a subsequent malignant disease course.

RESULTS

We describe a rare entity of follicular thyroid carcinoma that demonstrates a locally recurrent and eventually metastatic disease phenotype, despite persistently benign pathological findings.

CONCLUSION

We highlight that if local recurrence occurs in discrete anatomical tissue planes, or in the thyroid bed following open total thyroidectomy for 'benign multinodular goitre', the possibility of this rare presentation of follicular thyroid carcinoma should be considered.

[Analysis of BRAF and NRAS mutations in thyroid tumors in patients from Argentina]

INTRODUCTION

Molecular alterations in follicular cells in the BRAF or NRAS genes have been reported to be associated with the process of carcinogenesis. Our aim was to determine the mutational frequency of BRAF and NRAS in fine-needle aspiration (FNA) specimens in our population.

METHODS

The mutational status of BRAF (codon 600) and NRAS (codon 61) was analysed by qPCR in 193 FNA specimens from suspicious nodules and compared with pathological data of 115 patients.

RESULTS

BRAF mutation was identified in 40 samples (74.1%) of FNAs classified as Bethesda VI (n = 54). In samples histologically diagnosed as classic papillary thyroid carcinoma (cPTC, n = 47), mutation was observed in 70% of cases, while in other subtypes the prevalence was lower (p = 0.013). In FNA specimens of follicular lesions (n = 36), positivity for NRAS was found in 50% of the follicular carcinomas (FTCs), but only in 6.7% of adenomas. Finally, there was a significant correlation between BRAF and PTC with lymph-node metastasis (p = 0.014) and increased relative risk of recurrence based on the Argentine Intersociety Consensus (RR = 6.77, p = 0.022). No significant differences were found between BRAF mutation and other features of aggressiveness in PTC.

CONCLUSION

BRAF and NRAS mutations are observed in a significant number of PTCs and FTCs, in our population. There is a significant correlation between BRAF mutation and lymph-node metastasis.

Spindle cell variant of follicular thyroid carcinoma: an extremely unusual case and review of the literature

Spindle cell proliferations originating in follicular derived thyroid neoplasms are rare and known to cause diagnostic conundrums. We describe a unique case of a spindle cell variant of follicular thyroid carcinoma (FTC) in a 48-year-old female without relevant past medical history, who was being followed for a 1.4 cm left thyroid nodule for the past 15 months. A fine needle aspiration (FNA) of the nodule was interpreted as benign (Bethesda II). On follow-up ultrasound the nodule demonstrated a slight increase in size (to 1.5 cm) and the appearance of coarse calcifications A repeat FNA was performed 12 months later and interpreted as malignant neoplasm (Bethesda VI), containing a population of spindle and epithelioid cells that could not be further classified. A left subtotal thyroidectomy showed an encapsulated tumor mainly composed of fibroblast-like spindle cells, extensive foci of calcifications and focal ossification, with minimal tumor capsule invasion without vascular invasion. Tumor cells expressed vimentin, ERG and SMA (focal), while being negative for pancytokeratin, thyroglobulin, TTF-1, Pax-8, calcitonin, CEA and other lineage-specific mesenchymal, neuroendocrine and melanocytic markers. Importantly, a few residual thyroid follicles were identified within the nodule, and a diagnosis of minimally invasive FTC with extensive spindle cell changes, calcification and osseous metaplasia was rendered. This is only the second cytologic report of a pure spindle cell FTC. The rarity of this neoplasm and its potential broad differential diagnosis create diagnostic difficulties both on cytology and histology.

Follicular and Hurthle Cell Carcinoma: Comparison of Clinicopathological Features and Clinical Outcomes

Background: Follicular thyroid carcinoma (FTC) and Hurthle cell carcinoma (HCC) are rare and aggressive thyroid cancers with limited published data comparing their outcomes or regarding their subtypes. The aim of this study was to describe clinicopathological features and compare clinical outcomes of patients with FTC and HCC based on the 2017 World Health Organization definition and extent of vascular invasion (VI). Methods: We retrospectively studied 190 patients with HCC and FTC primarily treated with surgery at Memorial Sloan Kettering Cancer Center between 1986 and 2015. Patients were classified as minimally invasive (MI), encapsulated angioinvasive with focal VI (EA-FVI), encapsulated angioinvasive with extensive VI (EA-EVI), and as widely invasive (WI). To compare clinical outcomes, patients were grouped as follows: group 1 = FTC-MI and FTC EA-FVI, group 2 = FTC EA-EVI and FTC-WI, group 3 = HCC-MI and HCC EA-FVI, group 4 = HCC EA-EVI and HCC-WI. Outcomes of interest were overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), locoregional recurrence-free survival (LRRFS), and distant recurrence-free survival (DRFS). Outcomes were determined using the Kaplan-Meier method and compared with log-rank test. Results: Patients with HCC (n = 111) were more likely to be older than 55 years old (59% vs. 27%, p < 0.001) with a tendency to present with more extensive VI (33% vs. 19%, p = 0.07) compared with FTC (n = 79). Comparing groups 1, 2, 3, and 4, group 4 patients were more likely to recur (DFS 98%, 93%, 98% vs. 73%, respectively, p = 0.0069). There was no statistically significant difference in OS, DSS LRRFS, or DRFS. Stratified by extent of VI (no, focal, and extensive VI), patients with extensive VI were more likely to recur (RFS 100%, 95%, 77%, p = 0.0025) and had poorer distant control (DRFS: 100%, 95%, 80%, p = 0.022), compared with patients absent or focal VI. Conclusions: Accurate assessment of the extent of VI and tumor phenotype (follicular vs. Hurthle) are essential in identifying patients at higher risk of recurrence.

p53 protein expression in synchronously occurring dedifferentiating stages of thyroid cancer in a patient with neurofibromas: A case report

Poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid carcinoma (ATC) have been hypothesized to arise from well-differentiated thyroid carcinoma (WDTC) due to frequently reported synchronous and metachronous occurrence. Loss of normal p53 function has been implicated in this dedifferentiation process. The current case report presents a 60-year-old male with multiple neurofibromas who underwent total thyroidectomy due to multiple palpable thyroid nodules. Histopathological examination revealed three foci of predominantly papillary, but also follicular carcinoma growth pattern, and two lesions with histological features of insular and trabecular variant, with the larger one showing foci of anaplastic transition. Nuclear p53 protein accumulation, corresponding to mutant abnormally stabilized p53, was higher in more aggressive variants compared with WDTC. The somatic molecular events and downstream pathways of this dedifferentiation course have not been unraveled yet. The present case report demonstrated the simultaneous presence of three divergent histological subtypes in a single thyroid gland, with progressive enhancement of nuclear p53 protein expression, associated with mutant p53 protein, in the more aggressive variants. This is a rare case of progressive enhancement of mutant nuclear p53 protein expression in multifocal thyroid tumor areas consisting of WDTC, PDTC and ATC histological types, highlighting the possibility that WDTC can progress to PDTC and then ATC through an intricate procedure, involving loss of normal p53 function.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Finding in a Rare Case of Follicular Carcinoma of Thyroid with Rhabdoid Morphology

Rhabdoid tumor commonly occurs in the kidney and has an aggressive clinical course with high mortality. Extrarenal rhabdoid tumours can involve a number of organs, but poorly differentiated follicular carcinoma with rhabdoid phenotype is an extremely rare clinical entity. The 18F-FDG PET feature of this thyroid malignancy is not available in the literature to the best of our knowledge. But, this feature has significant clinical relevance in management of such patients. We present such a case.

Nature and outcome of malignant goiter: a revisit

Introduction

the aim of this retrospective study is to review patients with malignant goiter, as regards their nature, demographic characterization, clinical presentation and preoperative histopathological data.

Methods

the study focused on a period of 4 years from December 2015 to January 2019. Patients´ demographic data, clinical presentation, Intra-operative findings, Pre and postoperative histopathological staging and grading were all recorded. Postoperative follow up whether early or late were also included.

Results

a total of 100% (n = 65) patients underwent surgery. The female to male ratio was found to be 5:1 (48 females and 17 males). Solitary nodule was the main clinical presentation in 80% (n = 52) of cases while 20% (n = 13) were multinodular swellings. Papillary carcinoma was recorded in 80% (n = 52) of patients while in 15.4% (n =10) of patients were having follicular carcinoma. The remaining 4.6% (n = 3) suffered of lymphoma; no medullary or anaplastic tumors were reported.

Conclusion

thyroid cancer is the most commonly encountered endocrinal malignancy at our institute. Fine Needle Aspiration Cytology (FNAC) showed a high percentage of reliability in diagnosing thyroid cancer among our series. It is recommended to adapt this technique in initial screening of goiter patients in our local setting.

A case report

Struma ovarii is a monodermal variant of ovarian teratoma. Thyroid-type carcinoma arising in struma ovarii is rare. The most common type is papillary carcinoma, followed by typical follicular carcinoma. A 75-year-old hypertensive patient consulted for the sensation of a painless pelvic mass that has been progressing for six months. The abdominopelvic ultrasound showed a right lateralized abdominopelvic mass measuring 14x13x8 cm with a solid and cystic double component. The patient underwent a unilateral right adnexectomy. Grossly, the tumor was encapsulated and lobulated. On cut sections, it was solid brown whitish in color and gelatinous. On histological examination, it was formed of follicular structures of variable size filled with a dense colloid. From this goiter a malignant tumor proliferation arose, arranged in sheets, trabeculae and follicular structures, and the tumor cells were cubic or polyhedral moderately atypical with few mitotic figures. There were no papillary-like nuclear features. There was focal capsular and vascular invasion. Immunohistochemical study showed positive immunostaining of tumor cells with TTF1. Postoperative course was uneventful. The exact prognosis of thyroid-type carcinoma arising in struma ovarii is still unclear because of its rarity, inadequate follow-up, and the absence of consensus in diagnosis and treatment.

Raman Spectroscopy Discloses Altered Molecular Profile in Thyroid Adenomas

Follicular patterned nodules are sometimes complex to be classified due to ambiguous nuclear features and/or questionable capsular or vascular invasion. In this setting, there is a poor inter-observer concordance even among expert pathologists. Raman spectroscopy was recently used to separate benign and malignant thyroid nodules based on their molecular fingerprint; anyway, some histologically proved follicular adenomas were clustered as having a characteristic profile of malignant lesions. In this study, we analyzed five follicular thyroid adenomas with a malignant spectroscopic profile compared to five follicular adenomas with a benign Raman spectrum in order to assess possible molecular differences between the two groups. Morphological, immunohistochemical, and molecular analyses evidenced expression of malignancy-associated proteins in four out of five malignant clustered adenomas. The remaining malignant clustered adenoma showed a TSHR mutation previously associated with autonomously functioning follicular carcinomas. In conclusion, thyroid follicular adenomas are a group of morphologically benign neoplasms that may have altered the mutational or expression profile; cases of adenomas with altered immunophenotype are recognized as showing a profile associated with malignancy by Raman spectroscopy. This correlation warrants a more extensive evaluation and suggests a potential predictive value of spectroscopic assessment in recognizing characteristics associated with tumor progression in follicular thyroid neoplasms.

FOLLICULAR THYROID CARCINOMA - CLINICAL AND DIAGNOSTIC FINDINGS IN A 20-YEAR FOLLOW UP STUDY

Context

Follicular thyroid carcinomas (FTC) represent 6-10 % of all thyroid carcinomas; the evolution of FTC is quite controversial, partly due to frequent changes of the histopathological definition (minimally invasive-MIFTC or widely invasive carcinoma-WIFTC) and treatment strategies adjustments.

Objective

This research aims to examine the diagnostic procedure, therapeutic attitude and survival rates of patients with FTC, over a period of 16 years in the same institution, with a follow-up of at least 4 years, by analyzing correlations between histology subtype, treatments and the rate of recurrent disease.

Subjects and methods

We have studied 5891 patients with thyroid carcinomas who have undergone surgical or oncological treatment within the institution, between 1^st January 2000 - 31^st December 2015; among them we found 133 patients (2.25%) with "pure" follicular thyroid carcinoma: 114 (86%) women and 19 (14%) men, with a female-male ratio of 6:1. The age of the patients ranged from 10 to 76 years, with an average of 47.8 years. Statistical analysis was done comparing differences among groups of MIFTC and WIFTC.

Results

There was an unexpected high percentage of WIFTC and also an increased number of biochemically persistent and/or recurrent disease in patients with MIFTC. A stronger correlation was observed with the tumour dimensions, rather than with the histopathological subtype.

Conclusions

This research observed that overall survival was associated with tumour size rather than histopathological subtype and there is an important need to perform further studies to assess the effectiveness of treatment strategies.

Late-onset distant metastases confer poor prognosis in patients with well-differentiated thyroid cancer

Background

Distant metastases from well-differentiated thyroid carcinoma (WDTC) occasionally occur over a wide range of time intervals after primary thyroid surgery. The prognostic impact of the timing of distant metastasis onset remains unclear.

Methods

We retrospectively reviewed the clinicopathologic features and clinical outcomes of 57 patients with WDTC and distant metastases, and evaluated the mutational profiles of BRAF, RAS, and TERT promoter genes. All patients underwent thyroidectomy and radioactive iodine (RAI) ablation using the same treatment protocol. Synchronous distant metastases were defined as those detected within 12 months of the primary WDTC diagnosis. Metachronous metastases were considered early- and late-onset diseases if detected 1-5 and ≥5 years after the primary diagnosis, respectively.

Results

In all patients, the 5- and 10-year cancer-specific survival (CSS) rates after the diagnosis of distant metastasis were 86% and 57%, respectively. Late-onset (≥5 years) metachronous distant metastasis was associated with age of ≥55 years (P=0.043) and patients refractory to RAI therapy (P=0.026). TERT promoter mutations were associated with RAI refractivity (P=0.026). BRAF V600E and RAS mutations had no prognostic significance. Bone metastasis (P=0.002) and the onset time of distant metastasis (P=0.004) were associated with poor CSS. There was no significant difference in CSS between patients with synchronous distant metastases and those with early-onset (1-5 years) metachronous distant metastases. In the multivariate analysis, bone metastasis [hazard ratio (HR) =10.24; 95% confidence interval (CI): 1.25-83.74; P=0.030] and late-onset (≥5 years) metachronous distant metastasis (HR =5.20; 95% CI: 1.01-26.63; P=0.048) were independent predictors for worse CSS.

Conclusions

The prognosis of patients with WDTC was poorer for late metachronously detected metastases than for synchronous or early metachronous metastases. Patients with distant metastasis occurring 5 years later after primary thyroid diagnosis should, therefore, be more carefully treated.

Macrofollicular Variant of Follicular Thyroid Carcinoma: A Rare Underappreciated Pitfall in the Diagnosis of Thyroid Carcinoma

Background: Follicular-patterned thyroid nodules predominantly composed of macrofollicular structures without nuclear atypia are generally regarded as benign (i.e., hyperplastic nodules or follicular adenomas). In line with this concept, fine-needle aspiration cytology (FNAC) also assigns a benign connotation to the presence of macrofollicular structures, unless thyrocytes present papillary thyroid carcinoma (PTC)-related nuclear features that raise the possibility of a macrofollicular variant of PTC. However, cases showing macrofollicular architecture, capsular invasion, and no PTC features can also be observed. Methods: We describe the clinical, cytological, histological, and molecular genetic features of four cases of encapsulated follicular neoplasms that presented histologically with a predominant (>70%) macrofollicular architecture, but which also showed clear signs of capsular invasion, and thus were classified as macrofollicular variant of follicular thyroid carcinoma (MV-FTC). Results: Cytologically, macrofollicular structures were identified in all cases, leading to a benign FNAC diagnosis in three of the four cases. Due to increasing nodule size, thyroidectomy was performed in all cases. Histology showed focal and limited capsular invasion, without vascular invasion. Next-generation sequencing (custom 394 gene panel) of each tumor compared with matched normal DNA revealed a total of 7 somatic variants, including dual (likely biallelic) mutations in the DICER1 gene in 2 patients. The clinical outcome was excellent in all cases. Conclusions: Similar to the classical minimally invasive follicular thyroid carcinoma, MV-FTC appears to behave indolently. MV-FTC has a high rate of false-negative FNAC results, but MV-FTC is very rare (<0.05% of all thyroidectomies) and apparently has an indolent behavior. Further studies comprising larger series are necessary to better clarify the biology of this diagnostically challenging rare tumor.

Chest wall metastasis in postoperative thyroid cancer: a case report

Thyroid cancer is common in China. Thyroid adenocarcinoma metastases can be local or distal metastasis. Local metastasis presents as a hard and fixed lymph node in the neck, while distant metastases are found in the lung, skull, vertebrae, and pelvis. However, thyroid follicular carcinomas are mostly observed in hematogenous metastases. The thyroid adenocarcinoma and follicular carcinoma of the thyroid gland are often misdiagnosed. Here, we report the case of a 53-year-old female patient. More than 2 years after her initial diagnosis, her left chest wall was physically examined. The results revealed a progressive enlargement that had a hard quality, poor activity, unclear boundary, pressure pain, and percussion pain. Thyroid follicular cell carcinoma was subsequently diagnosed and treated surgically. The thyroid carcinoma had multiple bone metastases, and the thyroid follicular carcinoma had spread to the chest wall through the blood vessels. Thus, preoperative procedures and follow-up should be strengthened because early pathological thyroid follicular carcinoma and thyroid adenoma can easily be misdiagnosed. Pathologic consultation and follow-ups should be strengthened to prevent misdiagnosis.

Expression of SLC5A5 in Circulating Tumor Cells May Distinguish Follicular Thyroid Carcinomas from Adenomas: Implications for Blood-Based Preoperative Diagnosis

Preoperative diagnosis of thyroid nodules reduces unnecessary surgery. Circulating tumor cells (CTCs) may contain information of primary tumor(s). We asked whether the peripheral blood expression of genes specific for circulating tumor cells (CTCs) differentiates benign thyroid nodules from malignant nodules. Peripheral blood mononuclear cells from thyroid nodule patients (n = 20) were isolated preoperatively and the expression of seven CTC-associated genes was measured in patients with thyroid nodule(s) (n = 20). Among the tested genes, the expression of SLC5A5 and LGALS3 were validated in a larger number of patients (n = 64) and our results show that SLC5A5 expression differentiated follicular adenomas from follicular carcinomas (area under the curve (AUC) = 0.831). The expression of SLC5A5 in CTCs may preoperatively distinguish thyroid follicular adenomas from follicular carcinomas.

Cystathione β-Synthase Is Increased in Thyroid Malignancies

BACKGROUND

Cystathione β-synthase (CBS) catalyzes the conversion of homocysteine and cysteine to hydrogen sulfide (H₂S) and cystathione, via the trans-sulfuration pathway. CBS protein expression levels are increased in several different human malignancies, with increased protein expression correlating with parameters such as tumor stage, anaplasia, metastases, and chemotherapy resistance.

MATERIALS AND METHODS

This study employed tissue microarrays to examine CBS expression in benign thyroid tissue, thyroid oncocytomas, thyroid follicular adenomas, and in follicular, papillary, anaplastic, and medullary thyroid carcinomas.

RESULTS

CBS expression was increased in all thyroid carcinomas types compared to benign thyroid tissue, but not in thyroid follicular adenomas or oncocytomas. A similar pattern was observed for nicotinamide phosphoribosyltransferase (NAMPT) tissue microarray analysis comparing thyroid adenomas and follicular carcinomas.

CONCLUSION

For the first time, we showed that an H₂S-syntheszing enzyme plays a role in thyroid malignancies. Additionally, our data suggest that CBS and NAMPT immunohistochemistry may be useful in differentiating follicular adenomas from follicular carcinomas.

Thyroid follicular carcinoma in a teenager: A case report

A 19-year-old girl complained of an enlarged cervical mass. Based on clinical and cytological assessments, it was diagnosed as thyroid follicular carcinoma and left thyroidectomy was performed. Although thyroid neoplasms are rare in young people, differentiation is needed when the rapid growth of a goiter is detected.

Educational Case: Thyroid Neoplasms: Pathogenesis, Diagnosis, and Treatment

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.

Tumour growth rate of follicular thyroid carcinoma is not different from that of follicular adenoma

OBJECTIVE

Distinguishing malignancy from benign thyroid nodule has always been challenging, especially in follicular lesions. Thyroid nodules with small size and indeterminate cytology do not lead to immediate surgery. We tried to evaluate whether tumour size and tumour growth rate can distinguish follicular thyroid carcinoma (FTC) from follicular adenoma (FA).

DESIGN AND PATIENTS

This retrospective study included patients with pathologically proven FTCs (n = 50) and FAs (n = 110) who underwent preoperative serial neck ultrasonography (US) at least 3 times: it comprises 30% of all follicular tumours (32% FAs and 25% FTCs). The growth rates of follicular tumours on serial US were measured using at least 3 consecutive examinations during a median follow-up of 4.1 years (range, 0.7-13.3 years) by experienced radiologists.

RESULTS

The FA and FTC groups showed no significant difference in clinicopathological characteristics, including age, proportion of large nodules (>4 cm) and preoperative cytology. The maximum diameter of thyroid nodule was gradually increased in both groups with statistical significance (P < .001 and P < .001, respectively). No significant differences in change of maximum diameter of thyroid nodule (P = .132) and tumour volume (P = .208) were found between the FA and FTC groups during the follow-up. The median time to a significant tumour growth from baseline was not different between the FA and FTC groups (1.4 years and 1.7 years, respectively, P = .556). When we divided the patients into four groups (rapid, moderate, slow and no growth) according to the growth velocity of the thyroid tumours, no significant difference in growth velocity was found among the groups.

CONCLUSIONS

The tumour size and growth rate of the thyroid nodule itself could not predict malignancy. Diagnostic approaches that use molecular markers would be more important than clinical features for the decision of diagnostic surgery for patients with follicular tumours.

Malignant Solitary Fibrous Tumor Metastatic to Widely Invasive Hurthle Cell Thyroid Carcinoma: A Distinct Tumor-to-Tumor Metastasis

We illustrate a case of synchronous malignant solitary fibrous tumor of the thoracic cavity, and widely invasive thyroid Hurthle cell carcinoma. The Hurthle cell carcinoma was found to harbor distinct areas of malignant solitary fibrous tumor. This is a unique case of tumor-to-tumor metastasis that, to the best of our knowledge, has not been previously reported.

Genomic Hallmarks of Thyroid Neoplasia

The genomic landscape of thyroid cancers that are derived from follicular cells has been substantially elucidated through the coordinated application of high-throughput genomic technologies. Here, I review the common genetic alterations across the spectrum of thyroid neoplasia and present the resulting model of thyroid cancer initiation and progression. This model illustrates the striking correlation between tumor differentiation and overall somatic mutational burden, which also likely explains the highly variable clinical behavior and outcome of patients with thyroid cancers. These advances are yielding critical insights into thyroid cancer pathogenesis, which are being leveraged for the development of new diagnostic tools, prognostic and predictive biomarkers, and novel therapeutic approaches.

Cytodiagnosis of distant metastases from follicular thyroid carcinoma

INTRODUCTION

Follicular carcinoma of the thyroid is second most common primary malignancy of the thyroid gland after papillary carcinoma and metastasis is uncommonly seen in these patients.

AIMS AND OBJECTIVES

To describe the cytomorphologic features for the accurate diagnosis of distant metastases from follicular carcinoma of thyroid.

MATERIALS AND METHODS

A total of 10 aspirates reported as metastatic follicular carcinoma of thyroid were reviewed for the available clinical and radiological details.

RESULTS

All the patients were females. Six of these patients presented with subcutaneous and soft tissue swellings, one presented with a lung mass, one with right breast swelling, one with lumbar vertebral lesion and one with left iliac bone involvement. The cytology smears revealed tumour cells predominantly arranged in a repetitive microfollicular pattern with some scattered individually and in sheets. The tumour cells were small, had mild nuclear pleomorphism, round nuclei, low nuclear-cytoplasmic ratio, fine chromatin, inconspicuous nucleoli, and scanty to moderate amount of cytoplasm with some showing marginal vacuoles with "fire-flare" appearance. Occasional microfollicles showed scanty eosinophilic colloid in the center.

CONCLUSIONS

Identification and establishment of a correct clinical diagnosis of a distant metastasis from a follicular thyroid carcinoma is a challenging task. We believe that with prior knowledge of characteristic cytologic features, such metastases can be rapidly and accurately diagnosed by fine needle aspiration cytology.

Mucinous Variant of Follicular Carcinoma of the Thyroid Gland: Case Report and Review of the Literature

The rare reports of mucinous variant of follicular carcinoma of the thyroid gland have not provided enough evidence to support the recognition of these tumors as a distinct clinicopathologic entity or to understand their etiopathogenesis. We report the fourth case of mucinous variant of follicular carcinoma displaying a minimally invasive tumor with diffuse expression of thyroglobulin, TTF-1, CD56, PAX-8, cytokeratins 7 and 19, in the absence of monoclonal carcinoembryonic antigen (CEA), cytokeratin 20, chromogranin, HBME-1, P63 expression, and BRAF gene mutation, in a 51-year-old woman who is alive without signs of disease 13 months after total thyroidectomy, bilateral neck dissection, and radioactive iodine. Herein, fine-needle aspiration cytology disclosed "worrisome" cytologic features consisting of large epithelial cells arranged in clusters or singularly, with high nucleocytoplasmic ratio, nuclear grooves and evident nucleoli which were shared by those of mucin-producing papillary thyroid carcinoma. Therefore, knowledge of the cytological and histopathological spectrum of this lesion is important to avoid misdiagnosis. The morphologic clues leading to the correct diagnosis of mucinous variant of follicular neoplasm have been correlated with the data of the literature, and the differential diagnosis is briefly discussed.

Utility of sentinel lymph node biopsy for thyroid cancer: a comprehensive review

Sentinel lymph node biopsy (SLNB) is a minimally invasive lymphatic mapping technique, used to identify lymph node micrometastases and stage multiple cancer types. Despite the performance of SLNB for thyroid cancer having been under study since 1998, its role has remained controversial. The objective of this review is to summarize current research reporting on SLNB for thyroid cancer, focusing on recent studies of its application to differentiated thyroid cancer. The technique and potential benefits of SLNB are reviewed with regards to its ability to identify lymph node metastases, aid in cancer prognostication, and direct surgical and medical treatment.

Preoperative serum thyroglobulin concentration as a predictive factor of malignancy in small follicular and Hürthle cell neoplasms of the thyroid gland

BACKGROUND

Cytologic examination of a fine-needle aspiration biopsy specimen cannot distinguish between benign and malignant follicular or Hürthle cell neoplasms. Serum thyroglobulin (Tg) concentrations are higher in follicular and Hürthle cell carcinomas than in benign follicular or Hürthle cell tumors, but preoperative measurement of Tg is not recommended for initial evaluation of thyroid nodules. The aim of this study was to find out whether preoperative serum Tg concentration is a predictive factor of malignant disease in patients with a follicular or Hürthle cell neoplasm with a diameter of 2 cm or less.

METHODS

From 1988 to 2013, a total of 244 patients (214 female, 30 male, age range 9 to 82 years, median age 52 years) had a surgical procedure at our institute because of follicular or Hürthle cell neoplasms with a tumor diameter of 2 cm or less. In these patients a preoperative concentration of Tg was determined and Tg-autoantibodies were negative. The risk factors for malignancy were identified by a chi-square test and multivariate logistic regression.

RESULTS

The histopathologic diagnoses were carcinoma, adenoma, and benign goiter in 62 (25.5%), 115 (47%), and 67 (27.5%) patients, respectively. The median preoperative Tg concentration in benign tumors, papillary carcinomas, follicular carcinomas, and Hürthle cell carcinomas was 41, 87, 72, and 106 ng/ml (P = 0.05), respectively. The predictive factors for carcinoma shown by the chi-square test were: sex, thyroid volume, and preoperative Tg concentration. The independent predictors of malignancy as shown by multivariate logistic regression were: male sex (odds ratio, 2.57; P = 0.02), and a Tg concentration of more than 80 ng/ml (odds ratio, 2.35; P = 0.005).

CONCLUSION

The independent predictors of malignancy in follicular or Hürthle cell neoplasms are sex and preoperative Tg concentration.

Sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma

OBJECTIVES

The purpose of this study was to determine the sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma.

METHODS

This retrospective study included 36 pathologically proven follicular carcinomas (5 widely invasive and 31 minimally invasive) and 52 follicular adenomas in 88 patients who underwent thyroid surgery. We analyzed the sonographic features of each tumor, including maximum diameter, peripheral halo, echogenicity, echo texture, calcifications, and nodularity. The frequencies of the sonographic features were compared by χ(2) and Fisher exact tests between follicular adenomas and carcinomas. The relative risk of malignancy was evaluated by logistic regression analysis.

RESULTS

Predominantly solid contents, hypoechoic echogenicity, a heterogeneous echo texture, the presence of calcifications, and an absent or irregular thick halo were associated with follicular carcinoma (P < .05). Logistic regression analysis demonstrated that predominantly solid contents, a heterogeneous echo texture, and the presence of calcifications were associated with significant increases in the relative risk of follicular carcinoma (odds ratios, 9.4, 24.9, and 25.6, respectively; P < .01).

CONCLUSIONS

Sonography could provide useful information for differentiating follicular carcinoma from follicular adenoma.

Floating left innominate vein neoplastic thrombus: a rare case of mediastinal extension of follicular thyroid carcinoma

OBJECTIVE

We report a case of advanced follicular thyroid cancer with innominate vein involvement. To our knowledge, this seems to be the first case treated in emergency surgery, reported in literature.

METHOD

A 59-year-old woman with a five-year history of a large and mainly right-sided cervical mass presented with dyspnea, unilateral arm swelling, facial flushing, and venous congestion. An emergency computed tomography scan revealed a thyroid mass extending into the upper mediastinum with displacement and compression of the right jugular vein and carotid artery and apparent adherence to the superior vena cava and left innominate vein.

RESULTS

An emergency total thyroidectomy was performed by means of a sternotomy. The lower portion of the retrosternal goiter projected directly into the left innominate vein, with tumor floating in its lumen. Removal of the neoplastic thrombus was performed, through an incision in the vein, en bloc with the thyroid mass. Both goiter and thrombus were completely replaced by follicular carcinoma.

CONCLUSIONS

Accurate preoperative assessment through contrast-enhanced computed tomography is strongly suggested in the presence of enlarged thyroid gland extending into the mediastinum whenever angioinvasion is suspected. This could prevent blinded maneuvers such as digital externalization of the thoracic component of the gland, which can be fatal in cases of cervico-mediastinal goiter extending into great cervical or mediastinal veins.

Diagnostic value of galectin-3, HBME-1, cytokeratin 19, high molecular weight cytokeratin, cyclin D1 and p27(kip1) in the differential diagnosis of thyroid nodules

The distinction between benign and malignant thyroid tumors is critical for the management of patients with thyroid nodules. We applied immunohistochemical staining for galectin-3, HBME-1, cytokeratin 19 (CK19), high molecular weight cytokeratin (HMWCK), cyclin D1 and p27(kip1) in 295 thyroid lesions to determine their diagnostic accuracy. The expression of all markers was significantly associated with differentiated thyroid carcinoma (DTC). The sensitivity for the diagnosis of DTC was 94.7% with galectin-3, 91.3% with HBME-1, and 90.3% with CK19. The specificities of these markers were 95.5%, 69.7%, and 83.1%, respectively. Combining these markers, co-expression of galectin-3 and CK19 or galectin-3 and HBME-1 was seen in 93.2% of carcinomas but in none of the benign nodules. Comparing follicular variant of papillary carcinoma (FVPC) with follicular carcinoma (FC), the expression of galectin-3, CK19, and HMWCK was significantly higher in FVPC. When comparing FC with FA, the expression of galectin-3 and HBME-1 was significantly higher in FC. These results suggest that 1) galectin-3 is a useful marker in the distinction between benign and malignant thyroid tumors, 2) the combined use of HBME-1 and CK19 can increase the diagnostic accuracy, and 3) the use of CK19 and HMWCK can aid in the differential diagnosis between PC and FC.

Gene expression profiles in thyroid carcinomas

The gene expression profiles of human thyroid carcinomas were analysed by serial analysis of gene expression (SAGE) which allows quantitative and simultaneous analysis of a large number of transcripts. More than 29,000 transcripts derived from a normal thyroid tissue and four thyroid tumours were analysed. While extensive similarity was noted between the expression profiles of the normal thyroid tissue and three differentiated thyroid tumours, many transcripts, such as osteonectin, a-tubulin, glyceraldehyde-3-phosphate dehydrogenase, glutathione peroxidase, and thyroglobulin, were expressed at extremely different levels in differentiated and undifferentiated carcinomas. These data provide new information that might be used to identify genes useful for the diagnosis and treatment of thyroid carcinomas.