Anaplastic thyroid carcinoma. A study of 70 cases

Interaction between tumor stage and age on survival outcomes of patients with anaplastic thyroid cancer

BACKGROUND

Anaplastic thyroid cancer (ATC) is an aggressive, rare malignancy associated with rapid growth and metastasis, and a very poor prognosis. We investigated the clinical characteristics, survival outcomes and independent prognostic factors associated with anaplastic thyroid cancer.

AIM

To assess to what extent the interaction between age and tumor stage affects mortality.

METHODS

A total of 622 patients diagnosed with anaplastic thyroid cancer, between 2010 and 2017 were enrolled in our study by retrieving data from the Surveillance, Epidemiology and End Results (SEER) database. We analyzed demographics, clinical characteristics, overall mortality (OM) and cancer specific mortality (CSM) of ATC. Variables with a P value < 0.1 were incorporated into the multivariate cox model to determine the independent prognostic factors. Furthermore, we analyzed the interaction between age and tumor stage on mortality.

RESULTS

In the multivariate analyses, the divorced/separated population had a lower OM [hazard ratio (HR) = 0.63, 95%CI: 0.42-0.94, P < 0.05] and CSM (HR = 0.61, 95%CI: 0.40-0.92, P < 0.05). OM was higher in tumors with direct extension only (HR = 6.26, 95%CI: 1.29-30.42, P < 0.05) and tumors with distant spread (HR = 5.73, 95%CI: 1.34-24.51, P < 0.05). CSM was also higher in tumors with direct extension (HR = 5.05, 95%CI: 1.05-24.19, P < 0.05) and tumors with distant spread (HR = 4.57, 95%CI: 1.08-19.29, P < 0.05). Mortality was not adversely affected by lymph node involvement. OM was lower in patients who received radiation (HR = 0.66, 95%CI: 0.53-0.83, P < 0.01), chemotherapy (HR = 0.63, 95%CI: 0.50-0.79, P < 0.01) or surgery (HR = 0.53, 95%CI: 0.43-0.66, P < 0.01). CSM was also lower in patient who received radiation (HR = 0.64, 95%CI: 0.51-0.81, P < 0.01), chemotherapy (HR = 0.62, 95%CI: 0.50-0.78, P < 0.01) or surgery (HR = 0.51, 95%CI: 0.41-0.63, P < 0.01). There was no significant interaction between age and tumor stage that affected mortality.

CONCLUSION

In this large US SEER database retrospective study, we found the mortality to be higher in advanced stage tumors with direct extension and distant metastasis. However, patients who received aggressive therapy showed a better overall survival. The aim of our study is to emphasize the importance of detecting ATC at an early stage and provide aggressive therapy to these patients. Since advanced stage ATC is associated with a dismal prognosis, we emphasize the need for randomized control trials and development of novel therapies that will be used to treat ATC.

When to settle for SETTLE! A lesson learned from our cases

Spindle epithelial tumor with thymic like elements (SETTLE) is a biphasic tumor composed of epithelial and spindle cell components. It is an uncommon indolent tumor arising in the thyroid gland and most commonly affects the children and young adults. This entity is mostly overlooked because of its rarity and diagnostic difficulty on morphology. We discuss two cases of SETTLE with varied presentation, diagnostic challenges and lessons learnt from them.SETTLE should be considered as a differential especially when dealing with a thyroid lesion in young and adolescent. The article discusses the histologic details and common mimickers to be borne in mind aiding in arrival at the final diagnosis on biopsy specimens.

Genetic alterations in thyroid cancer mediating both resistance to BRAF inhibition and anaplastic transformation

A subset of thyroid cancers present at advanced stage or with dedifferentiated histology and have limited response to standard therapy. Tumors harboring the BRAF V600E mutation may be treated with BRAF inhibitors; however, tumor response is often short lived due to multiple compensatory resistance mechanisms. One mode of resistance is the transition to an alternative cell state, which on rare occasions can correspond to tumor dedifferentiation. DNA sequencing and RNA expression profiling show that thyroid tumors that dedifferentiate after BRAF inhibition are enriched in known genetic alterations that mediate resistance to BRAF blockade, and may also drive tumor dedifferentiation, including mutations in the PI3K/AKT/MTOR (PIK3CA, MTOR), MAP/ERK (MET, NF2, NRAS, RASA1), SWI/SNF chromatin remodeling complex (ARID2, PBRM1), and JAK/STAT pathways (JAK1). Given these findings, recent investigations have evaluated the efficacy of dual-target therapies; however, continued lack of long-term tumor control illustrates the complex and multifactorial nature of these compensatory mechanisms. Transition to an immune-suppressed state is another correlate of BRAF inhibitor resistance and tumor dedifferentiation, suggesting a possible role for concurrent targeted therapy with immunotherapy. Investigations into combined targeted and immunotherapy are ongoing, but early results with checkpoint inhibitors, viral therapies, and CAR T-cells suggest enhanced anti-tumor immune activity with these combinations.

Glomangiosarcoma-like Anaplastic Transformation in Papillary Thyroid Carcinoma: A Novel Form of Heterologous Differentiation and a Systematic Review of Heterologous Element Prevalence

Anaplastic thyroid carcinoma (ATC) demonstrates a wide variety of morphologies and is characteristically associated with a differentiated thyroid carcinoma component. Heterologous differentiation is a rare, potentially challenging phenomenon in ATC, mostly observed as osteosarcomatous or chondrosarcomatous differentiation. We now describe a novel 'glomangiosarcoma-like' differentiation, review our archival experience from two institutions (UPMC, CC), and perform a systematic review for the prevalence of heterologous elements in ATC. The patient is a 57-year-old female who presented with 4.5 cm left thyroid, and 3.4 cm neck masses. Histologically, the thyroid demonstrated a differentiated high grade papillary thyroid carcinoma, tall cell and hobnail/micropapillary subtypes transitioning into an anaplastic component with spindled to ovoid cells with hemangiopericytoma-like vasculature showing CD34 positivity, variable muscle marker expression and pericellular lace-like type IV collagen deposition. The neck mass consisted solely of the latter morphology. Targeted next-generation sequencing was performed on high grade DTC and adjacent ATC from the thyroid as well as ATC from the neck metastasis. All three components shared BRAFV600E, TERT promoter, and PIK3CA mutations confirming a clonal origin. Archival (UPMC: n = 150, CC: n = 74) and literature review showed no prior examples. Systematic review and meta-analysis of prevalence showed a baseline pooled prevalence (generalized linear mixed model) of heterologous elements of any type to be 1.6% (95% confidence interval: 1.0-2.6%) for studies where this was specifically addressed. ATC with glomangiosarcoma-like heterologous differentiation is a rarity among an already rare morphologic category with unique diagnostic pitfalls.

Efficacy and safety of anlotinib-based chemotherapy for locally advanced or metastatic anaplastic thyroid carcinoma

PURPOSE

Anaplastic thyroid carcinoma (ATC) is one of the most lethal malignancies with no effective treatment. In this study, we investigated the efficacy and safety of anlotinib-based chemotherapy as first-line therapy for ATC.

METHODS

Locally advanced or metastatic (LA/M) ATC patients who never received antitumor treatment of any sort were eligible for this study. The patients received 2-6 cycles anlotinib12mg on days 1-14 per 21 days. Chemotherapy regimens consisted of paclitaxel, capecitabine, or paclitaxel plus carboplatin/capecitabine. The end points including Objective Response Rate (ORR), Disease Control Rate (DCR), Progression-Free Survival (PFS), and Disease Specification Survival (DCS) were analyzed.

RESULTS

A total of 25 patients were enrolled. 1 patient achieved a Complete Response (CR) and 14 patients achieved Partial Response (PR). The best ORR was 60.0%, and the DCR was 88.0%. The median PFS was 25.1 weeks, and the median DCS was 96.0 weeks. Approximately 56% (14 patients) had at least one Adverse Event (AE) of any grade. Most AEs were well tolerated. The most common AEs was palmar-plantar erythrodysesthesia syndrome (28.0%).

CONCLUSIONS

Anlotinib-based chemotherapy as first-line therapy is a safe and effective intervention for the treatment of LA/M ATC patients.

Comparison of clinicopathological characteristics and survival between symptomatic and asymptomatic anaplastic thyroid carcinoma

Although anaplastic thyroid carcinoma (ATC) is a fatal form of thyroid cancer with an overall survival of only a few months, there are some factors associated with longer survival. However, it remains unknown whether asymptomatic ATC differs from symptomatic ATC in terms of characteristics and overall prognosis. Therefore, we aimed to examine the clinicopathological characteristics and prognosis of asymptomatic ATC compared with those of symptomatic ATC. We retrospectively reviewed the medical records of 113 patients with ATC who were registered at our institution between November 1994 and July 2020. A total of 86 patients (59 women and 27 men; mean age, 66.9 ± 11.1 years) were enrolled for analysis. The clinicopathological characteristics of the ATC cohort were evaluated, and prognostic factors associated with disease-specific mortality were assessed. Of the 86 patients with ATC, 78 were symptomatic and eight were asymptomatic. Compared with the symptomatic group, the asymptomatic group had a younger age at diagnosis (59.3 ± 10.3 vs. 67.7 ± 11.0 years, p = 0.045), smaller tumor size (2.8 ± 1.2 vs. 5.8 ± 2.0 cm, p < 0.001), and longer survival period (37.5 ± 46.4, 9.5 ± 16.8 months, p < 0.001). However, the ATC component (%) of the tumor, sex, ultrasonographic risk category, and distant metastasis at diagnosis did not differ significantly between the two groups. In the multivariate Cox regression analysis, asymptomatic ATC (HR: 0.33, 95% CI 0.11-0.99, p = 0.045) and absence of distant metastasis (hazard ratio (HR): 0.56, 95% Confidence interval (CI) 0.35-0.88, p = 0.012) were associated with longer survival. Patients with asymptomatic ATC have a smaller tumor size, a longer survival period, and a younger age than those with symptomatic ATC. Being asymptomatic and having no distant metastasis were associated with longer survival in patients with ATC in a clinical setting.

Advances in Thyroid Pathology: High Grade Follicular Cell-derived Thyroid Carcinoma and Anaplastic Thyroid Carcinoma

In the upcoming World Health Organization fifth edition classification of endocrine tumors, there were several major changes related to high grade follicular-derived thyroid carcinoma (HGFCTC) and anaplastic thyroid carcinoma (ATC) based on emerging evidence about the diagnostic criteria clinical behavior, prognostic factors, and molecular signatures of these tumors. In this review, we aim to summarize the major evolutions of HGFCTC and ATC. HGFCTC is a nonanaplastic carcinoma with high grade features (High mitotic count, tumor necrosis). It is subdivided into poorly differentiated thyroid carcinoma diagnosed using the Turin proposal and differentiated high grade thyroid carcinoma. The latter is defined by the presence of the cytoarchitectutal features of well-differentiated thyroid carcinoma (eg, papillae) but harbors elevated mitotic activity and/or tumor necrosis. Poorly differentiated thyroid carcinoma is predominantly RAS -driven and associated with RAI avidity and high propensity for distant metastasis, whereas differentiated high grade thyroid carcinoma is mostly BRAFV600E -driven. ATC may show a wide range of histologic features. Carcinoma of pure squamous phenotype is associated with a high frequency of BRAF V600E mutations and is now considered as a subtype of ATC. There is a stepwise molecular progression from well-differentiated carcinoma to HGFCTC to ATC manifested by 1) early and persistent driver alteration in the MAPK pathway, particularly BRAF V600E and RAS mutations, and 2) gain of secondary aggressive molecular signatures (such as TERT promoter and TP53 mutations) when tumors progress from well-differentiated to high grade to anaplastic carcinoma.

Prognosis of Anaplastic Thyroid Cancer with Distant Metastasis

Anaplastic thyroid cancer (ATC) is derived from follicular thyroid cells and is associated with high mortality risk. Obtaining information to characterize ATC is difficult because ATC with distant metastasis is extremely rare. This study determined the clinical characteristics of ATC with distant metastasis. The medical records of 152 patients with ATC at Gangnam Severance Hospital were reviewed between January 2004 and March 2022. The primary endpoint was the overall survival of the total patient sample, patients with ATC and distant metastasis, and those with ATC and brain metastasis. Of the 152 patients with ATC, 88 had distant metastasis at diagnosis. The 5-year disease-specific survival was 24% for total ATC and 10% for ATC with distant metastasis. Survival for >1 year was 32% for total ATC and 15% for ATC with distant metastasis. The median survival rate differed significantly between the total ATC and ATC with distant metastasis groups (228.5 vs. 171 days). Among the ATC cases, 11% had brain metastasis; thus, brain MRI or CT is worth considering at diagnosis and follow-up, even if there were no statistical difference in overall survival between patients with ATC with and without brain metastasis.

Anaplastik tiroid kanseri hücre hattının morfolojik analizi

Aim: Thyroid follicular cell derived cancers are classified into three groups such as papillary thyroid cancer (85%), follicular thyroid cancer (12%) and anaplastic (undifferentiated) thyroid cancer (ATC) (3%). ATCs have very rapid course, poor treatment outcomes and they are very aggressive. The aim of current study was to assess the analysis of the morphological differences of ATC cell line with the normal thyroid cell line (NTC). Materials and Methods: NTH and ATC cells were examined with haematoxylin and eosin, the nucleus: cytoplasm (N:C) ratios were detected, and cell cycles were investigated. These cell lines were compared according to their N:C ratio and their abundance in cell cycle phases. Results: The N:C ratio was higher in ATC than NTC. Both cell groups were mostly found in G0/G1 phase (68.4; 82.8) and have statistical difference in both G0/G1 and S phases. Conclusion: The rapid course and the rarity of ATC are significant barriers for clinical trials. Cultured cell lines are very important to explore the behaviour in the biology of ATC cells (such as the cell cycle), to understand the course of the disease, and to find an effective target for treatment.

Risk Factors for Anaplastic Thyroid Carcinoma: A Case Series From a Tertiary Referral Center for Thyroid Surgery and Literature Analysis

Anaplastic thyroid carcinoma (ATC) is a very rare and extremely aggressive disease with a very poor prognosis. Several risk factors have been hypothesized, but there is no clear-cut literature data on it. We reviewed the literature concerning risk factors for ATC and analyzed the institutional database from 2005 to 2022. In total, 15 papers were suitable for review, while the retrospective data collection search, conducted on our institutional database, provided 13 results. In our experience, in agreement with literature data, ATC seems to be a neoplasm peculiar to old age (in our database, mean age is 72 years), with a higher prevalence in subjects with a low level of education and a long history of multinodular goiter (MNG). The role of cigarette smoking and blood group, hypothesized on some literature data, was more uncertain, although the small sample size evaluated probably had a great influence on these results. The higher incidence of the disease in individuals with a history of MNG could suggest more aggressive choices in the treatment of a benign disease, in contrast to current practice. However, this may be a highly questionable point considering that ATC accounts for no more than 2% of all thyroid neoplasms in surgical departments, even those dedicated to endocrine neck surgery. Further studies are therefore necessary for a step forward in this direction.

YM155 Induces DNA Damage and Cell Death in Anaplastic Thyroid Cancer Cells by Inhibiting DNA Topoisomerase IIα at the ATP-Binding Site

Anaplastic thyroid cancer (ATC) is among the most aggressive of human cancers, and currently there are few effective treatments for most patients. YM155, first identified as a survivin inhibitor, was highlighted in a high-throughput screen performed by the National Cancer Institute, killing ATC cells in vitro and in vivo. However, there was no association between survivin expression and response to YM155 in clinical trials, and YM155 has been mostly abandoned for development despite favorable pharmacokinetic and toxicity profiles. Currently, alternative mechanisms are being explored for YM155 by a number of groups. In this study, ATC patient samples show overexpression of topoisomerase Top2α compared with benign thyroid samples and to differentiated thyroid cancers. ATC cell lines that overexpress Top2α are more sensitive to YM155. We created a YM155-resistant cell line, which shows decreased expression of Top2α and is resensitized with Top2α overexpression. Molecular modeling predicts binding for YM155 in the Top2α ATP-binding site and identifies key amino acids for YM155-Top2α interaction. A Top2α mutant abrogates the effect of YM155, confirming the contribution of Top2α to YM155 mechanism of action. Our results suggest a novel mechanism of action for YM155 and may represent a new therapeutic approach for the treatment of ATC.

Core Needle Biopsy Can Early and Precisely Identify Large Thyroid Masses

Background

Large thyroid masses, particularly if rapidly growing, are often characterized by compression and infiltration of the vital structures of the neck. Therefore, an early and precise diagnosis, not only of malignancy but also of histotype, is mandatory to set up the right therapy. The aim of this study was to evaluate the diagnostic performance of fine needle aspiration cytology (FNAC) and core needle biopsy (CNB) in this setting.

Patients and Methods

We prospectively evaluated 95 patients with large and rapidly growing thyroid masses admitted to the University Hospital of Pisa between April 2014 and January 2020. All patients were submitted to FNAC and CNB in the same session. The ability of both procedures to diagnose the malignancy of the lesions, particularly the histotype, and to obtain sufficient material to perform molecular analysis was evaluated.

Results

FNAC obtained adequate tumor sample to reach a diagnosis in 76 of 95 (80%) patients, while a higher percentage was obtained with CNB (92/95, 96.8%). FNAC was able to identify the malignancy of the lesion in 74 of 95 (77.9%) cases, but only in 16 of 74 (21.6%) cases was it able to define the histotype. CNB was able to define the malignancy of the lesion in all but three cases (92/95, 96.8%), and in all specimens, the histotype was identified. Moreover, in all cases, the material extracted from CNB was optimal to perform molecular analysis. No surgery-related complications were experienced with both procedures.

Conclusions

CNB is a rapid and safe procedure with higher performance compared to FNAC in identifying the histotype of large and rapidly growing thyroid masses. Moreover, adequate material can be obtained to characterize the molecular profile for the treatment of potentially lethal cancers. In the era of precision medicine, CNB should be introduced in routine clinical practice as a key procedure for an early diagnosis and therapy of these diseases.

Osteoclastic variant of anaplastic thyroid carcinoma: An insight into a rarest of rare entity

Anaplastic thyroid carcinoma is a rare and a very aggressive thyroid malignancy with a dismal prognosis. It has a short history and presents with a rapidly increasing neck mass associated with compressive symptoms like pain, hoarseness of voice, dysphagia and shortness of breath. Osteoclastic variant is an extremely rare variant, which is, characterize by presence of a large number of multinucleated giant cells, which resemble osteoclasts. Here we report two cases of this unusual variant in a 68 years old and 49 years old male with a short history of thyroid swelling.

Collision tumor of the thyroid - a challenge during the COVID-19 pandemic

Some of the patients with anaplastic thyroid carcinomas have a coexistent differentiated thyroid cancer, sustaining the hypothesis that this cancer may develop from more differentiated tumors. We describe a case with a collision tumor of the thyroid, defined as a neoplastic lesion composed of two distinct cell populations, with distinct borders. The patient presented during the COVID-19 pandemic with dysphonia, dyspnea, multinodular goiter and a painless, rapidly enlarging, left cervical swelling. She had been first time diagnosed with left nodular goiter in 2007, with an indication for surgery, which she declined. After partial excision of the left latero-cervical adenopathy, the pathological analysis showed massive lymph node metastasis from anaplastic thyroid cancer. A total thyroidectomy was done; the postoperative pathological exam identified a papillary thyroid microcarcinoma in the right lobe and an anaplastic thyroid cancer in the left lobe. Postoperatively, levothyroxine treatment was started and the patient was referred to radiotherapy. This case highlights the importance of urgent management of some cases with compressive multinodular goiter, even during the COVID-19 pandemic.

Immunotherapy for anaplastic thyroid carcinoma: the present and future

Anaplastic thyroid carcinoma (ATC) is the most malignant tumor of endocrine system, which is an urgent medical problem to be solved. At present, immunotherapy studies on ATC mainly include cutting off the recruitment of tumor-associated macrophage (TAM), inducing the reprogramming of TAM and restoring its phagocytic function, targeting related immune checkpoints on T cells and natural killer cells, tumor vaccines based on oncolytic viruses and dendritic cells, and adoptive immunotherapy. Among them, immunotherapy strategies represented by targeted blocking of programmed death-1/programmed death ligand-1 at immune checkpoint have been preliminarily confirmed to benefit ATC patients, especially the combination of molecular targeted inhibitors and immunotherapy has shown excellent therapeutic effects. Due to the great heterogeneity of ATC, it is expected to provide more therapeutic strategies for patients of ATC by carrying out various immunotherapy studies including biological, immune and cellular therapies and exploring the therapeutic potential of the next generation of immune checkpoint inhibitors. This article reviews the potential immunotherapeutic targets of ATC and the progress of immunotherapy.

Primary thyroid squamous cell carcinoma presenting as a left-sided neck lump

The elderly patient presenting with a neck lump often raises concerns regarding a malignancy. Thyroid gland malignancies are well recognised and subtype characteristics thoroughly researched, whereas rarer types of thyroid carcinoma are reported infrequently and often behave more aggressively. An 83-year-old woman was referred from the general practitioner (GP) to otolaryngology due to a 7-month history of an unexplained enlarging left-sided neck swelling. A fine-needle aspiration revealed cytology consistent with squamous cell carcinoma (SCC). Staging imaging failed to reveal evidence of a primary foci elsewhere. The definitive diagnosis was that of a primary thyroid SCC: a rare entity with limited citations in the literature. Surgical resection has been found to comprise the optimal treatment for this disease. Recognition of the possibility of primary thyroid SCC in elderly patients presenting with a neck lump, with prompt referral to a head and neck specialist permits a timely progression to potentially curative surgical management, a more promising prognosis and reduced mortality rates.

Immunohistochemically detectable thyroglobulin expression in extrathyroidal cancer is 100% specific for thyroidal tumor origin

Thyroglobulin is a secreted 660 kDa glycoprotein produced by thyroid follicular cells used in diagnostic pathology to secure or exclude a thyroidal origin of metastases of unknown primary tumors. This study was performed to estimate specificity of thyroglobulin immunohistochemistry. 9974 tumor samples from 109 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry in a tissue microarray format. Thyroglobulin was strongly expressed in all normal thyroid samples but not in any other normal tissues. Thyroglobulin immunostaining was detected in 99.1% of 106 thyroid adenomas, 98.1% of 364 papillary, 95.2% of 147 follicular, and 7.5% of 40 anaplastic thyroid cancers. Twelve of 15 thyroid samples that were thyroglobulin negative on TMAs showed at least a weak focal thyroglobulin positivity in corresponding large sections, suggesting higher sensitivity of large section analysis. Thyroglobulin positivity in one diffuse large B-cell lymphoma of the thyroid, one chondrosarcoma metastasis to the thyroid, and 42.4% of 92 medullary thyroid cancers was considered to be caused by diffusion of thyroidal colloid from destroyed or even intact adjacent follicles. Thyroglobulin positivity was, however, not seen in 6403 extrathyroidal tumors from 104 different tumor types and subtypes. Our data demonstrate a complete specificity of positive thyroglobulin immunostaining for thyroid origin in tumor tissues obtained from extrathyroidal locations. However, for all tumors located within the thyroid, false positivity can occur as a result of tissue contamination by thyroglobulin rich thyroid colloid from adjacent normal tissue.

Evaluation of E-Cadherin and β-Catenin Immunoreactivity for Determining Undifferentiated Cells in Anaplastic Thyroid Carcinoma

INTRODUCTION

An immunohistochemical study has occasionally been performed to diagnose anaplastic thyroid carcinoma (ATC). However, antibodies to confirm the undifferentiated nature of ATC have not yet been evaluated. The aim of this study was to evaluate E-cadherin and β-catenin expressions in immunoreactivity to determine undifferentiated carcinoma cells in the diagnosis of ATC.

METHODS

We immunohistochemically examined 29 ATCs, 30 poorly differentiated thyroid carcinomas (PDTCs), 22 well-differentiated thyroid carcinomas (WDTCs), and 3 squamous cell carcinomas. Antibodies for thyroid transcription factor-1 (TTF-1), paired-box gene 8 (PAX8), β-catenin, and E-cadherin were used.

RESULTS

All WDTCs tested positive for TTF-1, PAX8, and E-cadherin. The positive rates of TTF-1, PAX8, and E-cadherin were 93.3, 93.3, and 100%, respectively, in PDTCs and 17.2, 51.7, and 10.3%, respectively, in ATCs. WDTC expressed the lateral cell membrane staining for β-catenin and E-cadherin, whereas PDTC showed circumferential cell membranous expression (fishnet pattern). β-catenin cell membrane expression in ATCs is lost or discontinuous. Carcinoma cells with β-catenin nuclear expression without cell membranous expression were scattered in 72.4% of ATCs but were not observed in the other carcinomas.

CONCLUSION

We propose 3 immunohistochemical findings to determine undifferentiated carcinoma cells in the diagnosis of ATC: (1) β-catenin nuclear expression with no or reduced cell membranous expression, (2) the loss or discontinuous pattern of E-cadherin expression, and (3) the loss of PAX8 nuclear expression.

Metformin Reduces Thyroid Cancer Tumor Growth in the Metastatic Niche of Bone by Inhibiting Osteoblastic RANKL Productions

Background: Metformin has antitumoral actions in human cancers, including the thyroid, while its effects on metastatic lesions are unclear. Patients with bone metastasis (BM) from thyroid cancers have poor survival. Because metformin inhibits the activation of osteoclasts, which has essential roles in BM, the aim of this study was to investigate the therapeutic effects of metformin on thyroid cancer BM and osteoclast activation in the bone microenvironment. Methods: The anaplastic thyroid cancer (ATC) cell lines FRO and SW1736 were used to test the antitumoral effect of metformin in vitro and in vivo. A murine model of BM was established by intratibial injection of cancer cells. To mimic the BM microenvironment, osteoblasts were treated with conditioned media from the FRO (FRO-CM) and SW1736 (SW1736-CM) cells. Thyroid cancer patients with or without BM were recruited, and the serum receptor activator of nuclear factor kappa-B ligand (RANKL) levels was measured. Results: Metformin treatment significantly reduced the viabilities of the FRO and SW1736 cells in vitro and the tumor growth of SW1736 in vivo. In the murine model of BM, metformin delayed tumor growth in the bone and decreased the numbers of tartrate-resistant acid phosphatase-positive osteoclasts on the bone surface with reduced RANKL in the bone marrow. Furthermore, FRO- or SW1736-CM significantly increased the osteoblastic RANKL productions and activated osteoclast differentiation in whole marrow cultures, which were blocked by metformin treatment. Among 67 thyroid cancer patients, the serum RANKL levels were significantly increased in BM patients compared with patients with lung-only metastasis or no distant metastasis. In addition, the interleukin-6 superfamily in the FRO- or SW1736-CM stimulated STAT3 phosphorylation, which was inhibited by gp130 blocking. Metformin treatment decreased the FRO- or SW1736-CM-induced STAT3 phosphorylation by AMPK phosphorylation. Metformin also inhibited the FRO- or SW1736-CM-induced osteoclastic differentiation of bone marrow-derived monocyte/macrophage by RANK/c-Fos/NFATC1 signaling. Conclusions: In the microenvironment of BM, metformin effectively reduced ATC tumor growth by inhibiting cancer cell viability, blocking cancer cell-induced osteoblastic RANKL production, which further activated osteoclastogenesis, and directly reduced osteoclast differentiation. These multifactorial actions of metformin suggest that it has potential therapeutic effects in thyroid cancer BM.

2021 American Thyroid Association Guidelines for Management of Patients with Anaplastic Thyroid Cancer

Background: Anaplastic thyroid cancer (ATC) is a rare but highly lethal form of thyroid cancer. Since the guidelines for the management of ATC by the American Thyroid Association were first published in 2012, significant clinical and scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, and researchers on published evidence relating to the diagnosis and management of ATC. Methods: The specific clinical questions and topics addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of the Task Force members (authors of the guideline). Relevant literature was reviewed, including serial PubMed searches supplemented with additional articles. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations. Results: The guidelines include the diagnosis, initial evaluation, establishment of treatment goals, approaches to locoregional disease (surgery, radiotherapy, targeted/systemic therapy, supportive care during active therapy), approaches to advanced/metastatic disease, palliative care options, surveillance and long-term monitoring, and ethical issues, including end of life. The guidelines include 31 recommendations and 16 good practice statements. Conclusions: We have developed evidence-based recommendations to inform clinical decision-making in the management of ATC. While all care must be individualized, such recommendations provide, in our opinion, optimal care paradigms for patients with ATC.

Coexisting well-differentiated and anaplastic thyroid carcinoma in the same primary resection specimen: immunophenotypic and genetic comparison of the two components in a consecutive series of 13 cases and a review of the literature

Anaplastic carcinoma (AC) is a rare but highly aggressive form of thyroid cancer. It mostly arises on a background of pre-existing well-differentiated cancer (WDC); however, whether it evolves directly from a WDC or originates as a second independent neoplasm is still to be defined. To obtain further insights into these mechanisms, we performed morphological, immunohistochemical, and next-generation sequencing analyses to compare AC and its associated WDC in a subset of 13 surgically resected specimens. Histologically, most WDC were of aggressive subtypes. Papillary carcinomas (8 cases; 62%) were tall cell (4/8), columnar (1/8), classic with hobnail features (1/8), classic and follicular variant in the remaining 2 cases; Hürthle cell and follicular carcinomas were present in 5 (38%) and in 1 (8%) patient, respectively. One patient harbored both a PTC, follicular variant, and a Hürthle cell carcinoma. We did not find any correlation between a histotype of WDC and a specific anaplastic growth pattern. Immunohistochemically, ACs retained pankeratin/PAX8 expression but with significantly lower levels than WDCs, and they tended to lose TTF1 expression, as can be expected within a dedifferentiation process. In addition, AC showed a more frequent expression of p63 and/or SMA, a mutated pattern of p53, and an abnormal expression of p16. Genetic analysis showed that the number of mutations was higher in AC than in the associated WDC, confirming a role of the progressive accumulation of genetic damage in this transition. We observed that mutations found in the WDCs were consistently identified in the anaplastic counterparts, further supporting the hypothesis of a developmental link.

Airway management, symptom relief and best supportive care in anaplastic thyroid cancer

PURPOSE OF REVIEW

Anaplastic thyroid cancer (ATC) is a rare but aggressive form of thyroid cancer that is associated with significant morbidity and mortality. Because ATC is locally invasive, airway management is a critical component of treating these patients. Timely decisions regarding airway interventions can contribute to symptom relief and supportive care for patients. Over the last decade, there has been a paradigm shift in our recommendations for airway management. The purpose of this review is to summarize airway management, symptom relief and best supportive care for patients with ATC.

RECENT FINDINGS

More recent literature discusses the morbidities associated with tracheostomy and instead focuses on the benefits of supportive care and surgical resection. The multidisciplinary treating team should initiate early discussions for airway management, end-of-life care and palliative goals for patients with ATC. Tracheostomy should be offered to patients with careful thought and preoperative planning.

SUMMARY

Our goal in symptom relief and airway management is to improve the quality of life of patients with ATC and avoid the unnecessary morbidity of tracheostomy until clinically indicated.

Identification of Hub Genes in Anaplastic Thyroid Carcinoma: Evidence From Bioinformatics Analysis

Anaplastic thyroid carcinoma (ATC) is a rare type of thyroid cancer that results in fatal clinical outcomes; the pathogenesis of this life-threatening disease has yet to be fully elucidated. This study aims to identify the hub genes of ATC that may play key roles in ATC development and could serve as prognostic biomarkers or therapeutic targets. Two microarray datasets (GSE33630 and GSE53072) were obtained from the Gene Expression Omnibus database; these sets included 16 ATC and 49 normal thyroid samples. Differential expression analyses were performed for each dataset, and 420 genes were screened as common differentially expressed genes using the robust rank aggregation method. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential bio-functions of these differentially expressed genes (DEGs). The terms and enriched pathways were primarily associated with cell cycle, cell adhesion, and cancer-related signaling pathways. Furthermore, a protein-protein interaction network of DEG expression products was constructed using Cytoscape. Based on the whole network, we identified 7 hub genes that included CDK1, TOP2A, CDC20, KIF11, CCNA2, NUSAP1, and KIF2C. The expression levels of these hub genes were validated using quantitative polymerase chain reaction analyses of clinical specimens. In conclusion, the present study identified several key genes that are involved in ATC development and provides novel insights into the understanding of the molecular mechanisms of ATC development.

Anaplastic transformation of thyroid cancer in mesentery metastases presenting as intestinal perforation: a case report

Background

Anaplastic thyroid carcinoma is a highly aggressive form of thyroid cancer associated with a very poor prognosis. Anaplastic transformation most commonly occurs in the thyroid itself or within regional lymph nodes. Here we report the case of a patient with papillary thyroid cancer, presenting with colon perforation as a result of anaplastic transformation of metastases in the mesentery tissue. There have been no previous reports of this form of anaplastic transformation.

Case presentation

A 74-year-old man was admitted to our hospital, presenting with abdominal pain that he had been experiencing for 1 week prior to admission. The patient had a history of papillary thyroid carcinoma, for which he underwent a total thyroidectomy and mediastinal lymph node dissection 6 years earlier, and subsequently received radioactive iodine therapy for postoperative recurrence in the lung 2 years later. During the present reported admission, a computed tomography scan revealed a large intra-abdominal mass infiltrating into the colon and retroperitoneum and also highlighted the pneumoperitoneum. The patient was diagnosed with generalized peritonitis as a result of colon perforation, as such, we conducted an emergency laparotomy. Intraoperative findings showed a mass affecting the ascending colon and kidney, following which, an ileostomy and biopsy were completed. Poorly differentiated spindle cells were identified in the biopsy specimens, and histopathological and immunohistochemical findings revealed the absence of thyroid carcinoma cells. The tumor was therefore believed to be a primary sarcoma. Following surgery, the patient recovered from sepsis that had arisen as a result of colon perforation, however, rapidly developed systemic metastases and died 1 month post-operation. An autopsy was performed, and the patient was diagnosed with anaplastic papillary thyroid cancer at the mesentery site of metastasis. This conclusion was reached owing to the presence of the squamous differentiation of lymph node cells, and because tumor cells were positive results for paired-box gene 8 expressions.

Conclusions

Anaplastic transformation of papillary thyroid carcinoma should be considered in the diagnosis of a large mesentery mass in patients with a history of papillary carcinoma. An appropriate biopsy and paired-box gene 8 immunostaining can be useful in confirming such a diagnosis.

Anaplastic thyroid carcinoma with chondrosarcomatous differentiation: a case report

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is a rare malignant tumor. In addition to the main ATC type with classical histopathological features, the other morphological types of ATC include paucicellular variant, angiomatoid, lymphoepithelioma-like, and small-cell variant. However, an ATC variant with a chondrosarcomatous component has not been reported to date.

CASE PRESENTATION

Computed tomography imaging of a 63-year-old male with a 2-month history of a cervical mass revealed a 4.5-cm lesion with heterogeneous enhancement in the left thyroid lobe and two smooth and homogeneous nodules in the right thyroid lobe. The patient underwent total thyroidectomy and cervical lymph node resection. Histologically, the tumor boundary in the left lobe was clear, with a few mitotically active, spindle sarcoma-like tumor cells observed in some areas. Immunohistochemically, these spindle cells were positive for vimentin and negative for cytokeratin, paired box-8, epithelial membrane antigen, calcitonin, thyroglobulin, and thyroid transcription factor-1. In other areas, abundant cartilage matrix production and irregularly shaped lobules of cartilage, often separated by fibrous bands, were observed. The chondrocytes appeared mildly/moderately atypical and contained enlarged, hyperchromatic nucleoli. One of the two nodules in the right thyroid lobe had a clear boundary and comprised some bland spindle cells in a prominently collagenous stroma with clear boundaries. The other nodule in the right thyroid lobe was completely enclosed within a thin, fibrous capsule and exhibited normofollicular and microfollicular architecture. The patient received adjuvant radiotherapy after the surgery and was free of any local or regional recurrence or distant metastases at the 8-month follow-up evaluation.

CONCLUSIONS

This unusual case of ATC with chondrosarcomatous differentiation is an important addition to the morphology spectrum of ATC types.

Clear cell change in follicular adenoma of the thyroid. A diagnostic challenge

Clear cells in thyroid neoplasms can take two main forms: balloon-shaped and signet-ring cells. Balloon-shaped cell change in follicular adenoma is rare. A review of the literature has revealed only 20 previously published cases. We report herein a new case in the right thyroid lobe of a 45-year-old man. The clinicopathological data of the 21 cases including our paper have revealed that the ages of the patients ranged from 22-70 years, with a mean of 41.6 years. There was a clear predominance in women (M:F, 1:6). The most frequent location was in either of both lobes (81.8%), rarely affecting the isthmus. One case was observed in an ectopic thyroid in the submandibular region. The size ranged from 0.7-5.5 cm (mean 2.9 cm). The type of surgical intervention where this data was reported it was lobectomy for 10 (55.5%) cases, thyroidectomy for six (33.3%) cases, and simple excision for two (11.1%) cases. In one patient, the lobectomy was accompanied by cervical lymph node dissection. No cases recurred or extended outside the thyroid. The main differential diagnoses include intrathyroidal clear cell tumor of parathyroid origin, clear cell carcinoma of follicular, oncocytic, papillary, medullary or undifferentiated (anaplastic) origin, paraganglioma, metastatic clear cell carcinoma, especially of renal origin, metastatic balloon cell melanoma, and clear large-cell lymphoma. A thyroid lesion showing clear cell change constitutes a diagnostic challenge in cytological and biopsy diagnosis. Careful observation of the routine techniques along with the aid of an adequate immunohistochemical panel is essential to reach a correct biopsy diagnosis.

Thyroid Tumors You Don't Want to Miss

This article examines more uncommon thyroid entities, including anaplastic thyroid carcinoma, poorly differentiated thyroid carcinoma, rare papillary thyroid carcinoma variants, medullary thyroid carcinoma, non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), and multiple adenomatous nodules in the setting of Cowden syndrome. These entities were chosen based on their clinical significance and because they can be diagnostically challenging due to their morphologic diversity and overlap with other thyroid tumors. This article addresses the diagnostic features of each entity, focusing on how to avoid potential pitfalls and mimics while also highlighting the clinical implications of each diagnosis.

Mouse Model of Thyroid Cancer Progression and Dedifferentiation Driven by STRN-ALK Expression and Loss of p53: Evidence for the Existence of Two Types of Poorly Differentiated Carcinoma

Background: Thyroid tumor progression from well-differentiated cancer to poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid carcinoma (ATC) involves step-wise dedifferentiation associated with loss of iodine avidity and poor outcomes. ALK fusions, typically STRN-ALK, are found with higher incidence in human PDTC compared with well-differentiated cancer and, as previously shown, can drive the development of murine PDTC. The aim of this study was to evaluate thyroid cancer initiation and progression in mice with concomitant expression of STRN-ALK and inactivation of the tumor suppressor p53 (Trp53) in thyroid follicular cells. Methods: Transgenic mice with thyroid-specific expression of STRN-ALK and biallelic p53 loss were generated and aged on a regular diet or with methimazole and sodium perchlorate goitrogen treatment. Development and progression of thyroid tumors were monitored by using ultrasound imaging, followed by detailed histological and immunohistochemical evaluation. Gene expression analysis was performed on selected tumor samples by using RNA-Seq and quantitative RT-PCR. Results: In mice treated with goitrogen, the first thyroid cancers appeared at 6 months of age, reaching 86% penetrance by the age of 12 months, while a similar rate (71%) of tumor occurrence in mice on regular diet was observed by 18 months of age. Histological examination revealed well-differentiated papillary thyroid carcinomas (PTC) (n = 26), PDTC (n = 21), and ATC (n = 8) that frequently coexisted in the same thyroid gland. The tumors were frequently lethal and associated with the development of lung metastasis in 24% of cases. Histological and immunohistochemical characteristics of these cancers recapitulated tumors seen in humans. Detailed analysis of PDTC revealed two tumor types with distinct cell morphology and immunohistochemical characteristics, designated as PDTC type 1 (PDTC1) and type 2 (PDTC2). Gene expression analysis showed that PDTC1 tumors retained higher expression of thyroid differentiation genes including Tg and Slc5a5 (Nis) as compared with PDTC2 tumors. Conclusions: In this study, we generated a new mouse model of multistep thyroid cancer dedifferentiation with evidence of progression from PTC to PDTC and ATC. Further, PDTC in these mice showed two distinct histologic appearances correlated with levels of expression of thyroid differentiation and iodine metabolism genes, suggesting a possibility of existence of two PDTC types with different functional characteristics and potential implication for therapeutic approaches to these tumors.

A Systematic Review of Phase II Targeted Therapy Clinical Trials in Anaplastic Thyroid Cancer

Anaplastic thyroid carcinoma (ATC) is a rare, but devastating disease. Despite multimodal approaches combining surgery, chemotherapy and radiation therapy, ATC is associated with a dire prognosis, with a median overall survival of only three to ten months. Novel treatments are thus urgently needed. Recent efforts towards the characterization of the molecular landscape of ATC have led to the identification of pro-oncogenic targetable alterations, lending promise for novel targeted therapeutic approaches. This systematic review summarizes the results of phase II clinical trials of targeted therapy in ATC, providing an overview of efficacy and safety profiles. The majority of trials to date have consisted of small single-arm studies and have presented modest results. However, only a minority of trials have selected or stratified patients by molecular alterations. In the setting of BRAF V600E mutated ATC, dabrafenib/trametinib combination therapy and vemurafenib monotherapy have both demonstrated efficacy. Everolimus has furthermore shown promising results in patients with PI3K/mTOR/AKT pathway alterations. These studies underscore the importance of molecular profiling of tumors for appropriate patient selection and determination of genomic correlates of response. Clinical trials are underway testing additional targeted therapies as monotherapy, or as a part of multimodal treatment, and in combination with immunotherapy.

Cytologic features of aggressive variants of follicular-derived thyroid carcinoma

Certain carcinomas of the thyroid gland behave aggressively resulting in increased patient morbidity and poor patient prognosis. The diagnosis of these aggressive thyroid cancer subtypes is sometimes challenging and subject to increased interobserver variability. This review deals with the cytological features of such tumors including aggressive variants of papillary thyroid carcinoma, poorly differentiated thyroid carcinoma, and anaplastic thyroid carcinoma. These malignancies fall into 2 groups based on their cytomorphology: those that exhibit distinct microscopic features (eg, nuclear findings typical of classical papillary thyroid carcinoma or marked anaplasia) and those that present with more subtle cytologic features (eg, nuclear pseudostratification, "soap bubble" nuclei, supranuclear or subnuclear cytoplasmic vacuoles, rosette-like structures, hobnail cells). We review the literature regarding these aggressive thyroid cancers and highlight important phenotypic characteristics that can be useful for their diagnosis based on fine needle aspiration.

Special types of thyroid carcinoma

This article reviews the small percentage of thyroid tumours that are not classified as classic papillary thyroid carcinoma, follicular thyroid carcinoma, and medullary thyroid carcinoma. It includes subtypes of papillary thyroid carcinoma, including, tall-cell, hobnail/micropapillary, columnar cell, diffuse sclerosing and solid variants. Poorly differentiated carcinoma, high-grade carcinoma and anaplastic thyroid carcinoma are reviewed. Also discussed are entities that are unusual but need to be recognized as primary thyroid neoplasms, i.e. mucoepidermoid carcinoma, sclerosing mucoepidermoid carcinoma with eosinophilia, and mammary analogue secretory carcinoma/secretory carcinoma. The pathological features and prognostic factors are described; a brief review of molecular correlates of these neoplasms is included.

Anaplastic thyroid carcinoma: an epidemiologic, histologic, immunohistochemical, and molecular single-institution study

Anaplastic thyroid carcinoma (ATC) is a highly aggressive form of thyroid cancer. A single-institution thyroid cancer cohort of ATC was identified within the last 10 years at our institution. Retrospective analysis revealed that the frequency of ATC was 0.5% (11/2106 thyroid carcinomas). The average age at diagnosis of ATC was 74 years, and the female-to-male ratio was 1.2:1. ATC presented as a rapidly enlarging neck mass involving predominantly the left thyroid lobe (7/11; 64%). Cervical adenopathy was present in 7 (64%) of 11 cases. Fifty-five percent (6/11) of patients had distant metastases at the time of diagnosis. Histologically, ATC closely simulated a large variety of soft tissue sarcomas; osteoclast-like giant cell-rich tumors; squamous cell, spindle cell, and small cell carcinomas; and anaplastic/large cell lymphomas. Four tumors (4/11; 36%) showed heterologous elements, including rhabdoid and chondroid differentiation. Immunohistochemical studies showed that all ATCs lost TTF-1 and thyroglobulin expression, whereas PAX-8 expression was identified in 36% (4/11) of tumors. Intense and extensive nuclear staining of p53 (>50%) and high Ki-67 proliferative rate (>30%) were seen in all ATCs (11/11; 100%). Next-generation sequencing revealed recurrent BRAF V600E and TP53 gene mutations. Individual examples of a BRAF G469A mutation in ATC with follicular carcinoma component, EGFR, PTEN, PIK3CA, and FGFR3 mutations, were also identified, whereas 1 case of ATC showed wild-type sequencing with no identifiable alterations.

Pleomorphic Carcinoma of the Gallbladder: Report of a Case

The authors report a rare case of primary pleomorphic carcinoma of the gallbladder in a 70-year-old woman. A polypoid tumor protruded into the lumen from the fundus of the gallbladder. Characteristic histologic findings Included a general lack of architectural cohesiveness, marked pleomorphism, presence of mononucleated and multinucleated giant cells, extensive necrosis, leukocyte-tumor cell phagocytosis or cannibalism. Immunoreactivity for cytokeratin, carclnoembryonic antigen and epithelial membrane antigen as well as histochemical positivity for mucins demonstrated the epithelial nature of the tumor. The neoplasm behaved aggressively; the patient died of metastases 9 months after the operation.

Neoplastic and Non-neoplastic Thyroid Lesions in Autopsy Material: Historical Review of Six Decades in São Paulo, Brazil

Aims and background

The aim of the study was to report and discuss a historical series of neoplastic and non-neoplastic lesions of the thyroid gland obtained at autopsy that were examined between 1931 and 1989 at the Pathology Department of the Medical School of the University of SaTo Paulo.

Methods

Records of 145,043 cases were reviewed to select those affecting the thyroid gland. The slides of these selected cases were analyzed and classified according to the current terminology.

Results

Non-neoplastic lesions comprised 91.62% of the cases (n=4647), and most of them were adenomatous goiter (n=3014). Neoplastic lesions were divided into two groups: primary and metastatic. Of the 282 primary tumors, 135 were benign and 147 were malignant. Among the malignant neoplasms, the most frequent types were follicular, papillary and undifferentiated (n=39, 36 and 29, respectively). The most frequent tumor types among the metastatic neoplasms were lymphoproliferative processes and carcinomas (n=67 and 34, respectively).

Conclusions

We conclude that, because of the high frequency of neoplastic lesions (8.38%), 68.24% of which were malignant, detailed examination of the thyroid by pathological methods should be carefully and systematically performed for the accurate detection of thyroid lesions, especially carcinomas.

Anaplastic thyroid carcinoma: from clinicopathology to genetics and advanced therapies

Anaplastic thyroid carcinoma (ATC) is a rare malignancy, accounting for 1-2% of all thyroid cancers. Although rare, ATC accounts for the majority of deaths from thyroid carcinoma. ATC often originates in a pre-existing thyroid cancer lesion, as suggested by the simultaneous presence of areas of differentiated or poorly differentiated thyroid carcinoma. ATC is characterized by the accumulation of several oncogenic alterations, and studies have shown that an increased number of oncogenic alterations equates to an increased level of dedifferentiation and aggressiveness. The clinical management of ATC requires a multidisciplinary approach; according to recent American Thyroid Association guidelines, surgery, radiotherapy and/or chemotherapy should be considered. In addition to conventional therapies, novel molecular targeted therapies are the most promising emerging treatment modalities. These drugs are often multiple receptor tyrosine kinase inhibitors, several of which have been tested in clinical trials with encouraging results so far. Accordingly, clinical trials are ongoing to evaluate the safety, efficacy and effectiveness of these new agents. This Review describes the updated clinical and pathological features of ATC and provides insight into the molecular biology of this disease. The most recent literature regarding conventional, newly available and future therapies for ATC is also discussed.

Rare Manifestations of Anaplastic Thyroid Carcinoma: the Role of BRAF Mutation Analysis

Anaplastic thyroid carcinoma (ATC) is difficult to distinguish from other cancers, especially when its pathological features are atypical for ATC or when the tumor is totally undifferentiated and occurs after a considerable lapse of time, in an area remote from the original site of the tumor. Here, we present two patients (68-year-old man and 56-year-old woman) with rare manifestations of ATC, which were initially thought to be other malignancies. Immunohistochemical tests, using various markers, failed to provide information about the origin of these tumors. However, both patients had a history of papillary thyroid carcinoma (PTC) from several years ago and BRAF mutations were observed in the undifferentiated tumors, as well as in the previous PTCs. Therefore, we could make a diagnosis of ATC derived from PTC. As such, BRAF mutation analysis may serve as a useful tool for ATC diagnosis in challenging ATC cases.

Poorly Differentiated and Anaplastic Thyroid Cancer

BACKGROUND

Poorly differentiated thyroid carcinoma (PDTC) and anaplastic (undifferentiated) thyroid carcinoma (ATC) comprise a small subset of thyroid tumors that are associated with a poor prognosis and account for a significant portion of the morbidity and mortality related to thyroid cancer. Since management strategies vary between these two entities, it is important for clinicians to be able to differentiate PDTC from ATC.

METHODS

We reviewed the literature on PDTC and ATC and compared clinical and histopathologic features important in defining the disease process.

RESULTS

Both PDTC and ATC display aggressive behavior with increased locoregional and distant disease. In most cases, patients are older and have large, locally advanced tumors. PDTC may represent an intermediate entity in the progression of well-differentiated thyroid carcinoma to ATC. The use of surgical management may be curative or palliative and differs between PDTC and ATC. The roles of radiotherapy and chemotherapy have not been well described.

CONCLUSIONS

PDTC and ATC are rare diseases that carry a poor prognosis. Recognition of their different clinicopathologic features is important to the optimal management of these tumors.

Cytological Diagnosis of an Uncommon High Grade Malignant Thyroid Tumour: A Case Report

Anaplastic Thyroid Carcinoma (ATC) is a relatively uncommon highly malignant tumour originating from the follicular cells of thyroid gland having poor prognosis. It accounts for 2% to 5% of all thyroid carcinomas and patients typically present with a rapidly growing anterior neck mass with aggressive symptoms. A 53-year-old male presented with diffuse neck swelling measuring 8x6 cm and right cervical lymph node measuring 2x2 cm since one month which was associated with dyspepsia and dyspnoea. Ultrasound and Contrast Enhanced Computed Tomography (CECT) neck revealed enlarged right lobe of thyroid and multiple enlarged cervical lymph nodes with soft tissue density nodules in bilateral lungs. Fine Needle Aspiration (FNA) from the swelling revealed giant cell, spindle cell and squamoid pattern. Focal areas showed follicular epithelial cells arranged in repeated microfollicular pattern suggesting an underlying follicular neoplasm. FNAC smears from the lymph node also revealed similar findings. Based on the cytomorphological and radiological findings, final diagnosis of ATC probably arising from underlying follicular carcinoma with cervical lymph node and lung metastasis was given. FNAC leads to prompt and definitive diagnosis, so that therapy can be initiated as soon as possible for better outcome. Multimodality therapy (surgery, external beam radiation, and chemotherapy) is the mainstay of treatment.

Atypical adenoma of the thyroid diagnosed as anaplastic cancer by cytopathology

Atypical adenoma of the thyroid is a rare form of tumor, and its accurate diagnosis prior to surgical resection is difficult as the histological and pathological morphologies are very similar to those of anaplastic thyroid carcinoma (ATC), and its anaplastic transformation remains to be elucidated. We reported a case of a 75-year-old female with a thyroid isthmus nodule diagnosed repeatedly by FNAC as anaplastic carcinoma. Both the first and second FNAC specimen slides showed a large number of scattered or aggregated atypical cells consisting of large, pleomorphic nuclei with irregular membranes, chromatin clumps and prominent nucleoli. The morphology of the surgical specimen was similar to that of an anaplastic carcinoma and although it showed signs of transition from a normal follicular epithelium, there was no invasive growth or mitosis. This lesion was diagnosed as an atypical adenoma, and a papillary carcinoma was also present in the right lobe of the thyroid. Here we evaluate the molecular features of atypical adenomas in comparison with 9 ATC samples, and discuss whether or not atypical adenomas represent a form of premalignant lesion. Ki-67 expression was found to be very low in atypical adenomas whereas all ATC samples showed high levels of Ki-67 expression. Epithelial-mesenchymal transition (EMT) marker expression suggested that atypical adenomas maintain their epithelial phenotype to a higher degree than do ATCs. Differential diagnosis between ATC and atypical adenoma is difficult by cytological and histological methods alone, and Ki-67 and EMT marker expression may support the diagnosis.

Patterns of Treatment Failure in Anaplastic Thyroid Carcinoma

BACKGROUND

Anaplastic thyroid cancer (ATC) is one of the most lethal forms of cancer with a high mortality rate. Current guidelines support surgery for resectable ATC followed by external beam radiation therapy (EBRT) with or without chemotherapy. Treatment for those who are unresectable is palliative. Our goal was to examine first-line therapies as well as the role of genomic profiling in an effort better understand how to approach ATC.

METHODS

This is a retrospective study of ATC patients who were seen at our institution from January 2013 to October 2015. Median overall survival (OS) and time to treatment failure (TTF) were calculated by the Kaplan-Meier method.

RESULTS

Fifty-four patients were included. Median age at diagnosis was 63 years and 29/54 (54%) were women. The majority had stage IVC disease at diagnosis (50%), followed by IVB (32%), and IVA (18%). Approximately 93% had somatic gene testing. Initial treatment was surgery in 23 patients, EBRT with or without radiosensitizing chemotherapy in 29 patients, and systemic chemotherapy in 2 patients. Nineteen patients had all three treatment modalities. For the entire cohort, median OS was 11.9 months with 39% survival at 1 year and median TTF was 3.8 months. The majority of patients (74%) developed new distant metastasis or progression of existing metastatic disease. Patients who received trimodal therapy consisting of surgery, EBRT, and chemotherapy had a median OS of 22.1 months versus 6.5 months in those who received dual therapy with EBRT and chemotherapy (p = 0.0008). The TTF was the same in the two groups (7.0 and 6.5 months, respectively). Men were three times more likely to die from ATC than women (p = 0.0024). No differences in OS or TTF were noted based on tumor size (5 cm cutoff), age (60 years cutoff), or presence of any mutation. There was a trend toward shorter TTF in patients with somatic mutations in TP53.

CONCLUSION

Patients with ATC amenable to aggressive tri-modal therapy demonstrate improved survival. The short TTF, due primarily to distant metastatic disease, highlights the potential opportunity for improved outcomes with earlier initiation of systemic therapy including adjuvant or neoadjuvant therapy.

A Case Report on Multiple Stones in the Thyroid Gland in Association with Sclerosing Thyroiditis: An Unusual Encounter

Stones are very frequently found in the gallbladder and urinary tract. Rarely the thyroid gland can be a site for stone formation. Few cases of calcification in thyroid gland have been described in the medical literature in association with papillary carcinoma and multinodular goiter. A unique case of a thyroid swelling studded with multiple stones in its parenchyma, in the histopathological background of sclerosing thyroiditis in an 80-year-old male is documented here. Surgical excision was undertaken with an uneventful postoperative period.

Glycolysis-related protein expression in thyroid cancer

We aimed to demonstrate the differences in the expression of glucose metabolism-related proteins according to the thyroid cancer subtypes and investigate the implications of these differences. A total of 566 thyroid cancer patients, including 342 cases of papillary thyroid carcinoma, 112 cases of follicular carcinoma, 70 cases of medullary carcinoma, 23 cases of poorly differentiated carcinoma, 19 cases of anaplastic carcinoma, and 152 cases of follicular adenoma, were enrolled in the study. Immunohistochemical staining for glucose transporter 1, hexokinase II, carbonic anhydrase IX, and monocarbonylate transporter 4 was performed, and the relationship between immunoreactivity and clinicopathologic parameters was analyzed. Glucose transporter 1 and tumoral monocarbonylate transporter 4 expression levels were shown to be the highest in anaplastic carcinoma, and medullary carcinoma showed the highest carbonic anhydrase IX and lowest hexokinase II levels compared with other subtypes. Stromal expression of monocarbonylate transporter 4 was observed in papillary thyroid carcinoma and anaplastic carcinoma samples. Conventional papillary thyroid carcinoma tumors expressed higher levels of glucose transporter 1, and tumoral and stromal monocarbonylate transporter 4, than the follicular variant, which showed a higher expression of carbonic anhydrase IX. Papillary thyroid carcinoma samples with BRAF V600E mutation were shown to have higher glucose transporter 1, hexokinase II, carbonic anhydrase IX, and tumoral monocarbonylate transporter 4 expression levels. Univariate analysis showed that papillary thyroid carcinoma cases with glucose transporter 1 positivity had shorter overall survival, patients with medullary carcinoma and hexokinase II positivity were shown to have a shorter disease-free survival and overall survival, and tumoral monocarbonylate transporter 4 positivity was associated with shorter overall survival compared with papillary thyroid carcinoma patients with negativity for each marker. Disease-free survival and overall survival of patients with poorly differentiated carcinoma were shown to be significantly decreased when glucose transporter 1 and tumoral monocarbonylate transporter 4 are expressed. We demonstrated that the expression levels of glycolysis-related proteins differ between thyroid cancer subtypes and are correlated with poorer prognosis, depending on the subtype.

Macrophage Densities Correlated with CXC Chemokine Receptor 4 Expression and Related with Poor Survival in Anaplastic Thyroid Cancer

BACKGROUND

Tumor associated macrophages (TAMs) and CXC chemokine receptor 4 (CXCR4) have emerged as potential biomarkers in various human cancers. The aims of this study were to investigate the clinical characteristics of anaplastic thyroid cancer (ATC) patients according to the TAM numbers in the tumor tissue, and to evaluate the associations between CXCR4 expressions and macrophage densities in ATC tumor microenvironment.

METHODS

Total 14 ATC samples from thyroid tissue microarray were used. Immunohistochemical staining was performed using anti-CD163 and anti-CXCR4 antibodies. According to the immunoreactivity of CD163, all subjects were divided into two groups: low-CD163 (n=8) and high-CD163 (n=6) groups.

RESULTS

The mean diagnostic age was 65±7 years and the median tumor size was 4.3 cm, ranging 2.5 to 15 cm. Clinicopathological characteristics were not significantly different between low-CD163 and high-CD163 groups, while age of diagnosis was younger in high-CD163 group than that of low-CD163 group with marginal significance (56.9±5.5 years vs. 67.5±6.8 years, P=0.09). However, overall survival was significantly reduced in high-CD163 group (5.5 months [range, 1 to 10]) compared with low-CD163 groups (8.8 months [range, 6 to 121); log-rank test, P=0.0443). Moreover, high-CD163 group showed strong CXCR4 expressions in both cancer and stromal compartments, while low-CD163 group showed relatively weak, stromal-dominant CXCR4 expressions. Additionally, CD163 and CXCR4 expressions showed a strong positive correlation (γ²=0.432, P=0.013).

CONCLUSION

Increased number of TAMs showed poor overall survival in ATC, suggesting TAMs are potentially a prognostic biomarker for ATC. CXCR4 expression was significantly correlated with CD163-positive TAM densities, which suggest the possible role of CXCR4 in TAM recruitments.

Description and Comparison of the Sonographic Characteristics of Poorly Differentiated Thyroid Carcinoma and Anaplastic Thyroid Carcinoma

OBJECTIVES

Although poorly differentiated thyroid carcinoma and anaplastic thyroid carcinoma account for a substantial portion of the morbidity and mortality associated with thyroid cancer, a chance of a cure exists with aggressive treatment, especially in patients with poorly differentiated thyroid carcinoma. The goal of this study was to evaluate the sonographic characteristics of poorly differentiated thyroid carcinoma and to compare the sonographic findings of poorly differentiated and anaplastic thyroid carcinomas.

METHODS

The study included 29 patients with 30 poorly differentiated thyroid carcinomas and 26 patients with 26 anaplastic thyroid carcinomas. Two radiologists retrospectively reviewed sonographic findings. Clinical and sonographic findings were compared between poorly differentiated and anaplastic thyroid carcinomas by univariate and multivariate analyses.

RESULTS

In the group of patients with poorly differentiated thyroid carcinoma, the mean age was 53.7 years (range, 14-73 years), and the mean tumor size was 3.6 cm (range, 0.6-10.0 cm). The common sonographic findings of poorly differentiated thyroid carcinoma were heterogeneous echogenicity (93.3%), solitary nodules (80.0%), a circumscribed margin (63.3%), an oval-to-round shape (63.3%), and hypoechogenicity (60.0%). A circumscribed margin (P = .003) and an oval-to-round shape (P = .015) were significantly more frequent in poorly differentiated thyroid carcinoma than in anaplastic thyroid carcinoma. In the multivariate analysis, only the circumscribed margin on sonography was an independent predicting factor for poorly differentiated thyroid carcinoma (odds ratio, 4.642).

CONCLUSIONS

Both poorly differentiated thyroid carcinoma and anaplastic thyroid carcinoma commonly present as a relatively large malignant mass on sonography; however, poorly differentiated thyroid carcinoma showed a significantly higher incidence of a circumscribed margin and an oval-to-round shape than anaplastic thyroid carcinoma. Knowledge of sonographic characteristics will be useful for differentiation of poorly differentiated and anaplastic thyroid carcinomas.

Diagnostic immunohistochemistry through Rosai-coloured glasses

Over the past three decades, Immunohistochemistry has materially changed the practice of diagnostic surgical pathology. Foundational observations in this field were critical to a reasoned assessment of both the risks and opportunities that immunohistochemistry afforded the surgical pathologist, and our current practice draws heavily on those early assessments. As we collectively look to and acknowledge those who recognized the value of this technique and who helped guide its development as a companion to (not a replacement for) histomorphologic evaluation, we are drawn to those whose mastery of detail and ability to draw common patterns from seemingly unrelated phenomena helped define the diagnostic power of immunohistochemistry. The focus of this review is on one individual, Dr. Juan Rosai, whose contributions transcend the simple linkage of molecular observations to morphology, recognizing novel patterns in both form and color (the latter often the lovely shades of diaminobenzidine), seemingly viewing our diagnostic world at times through an entirely different lens. By looking at Dr. Rosai's early work in this field, reviewing a selection of his seminal observations, particularly in the Immunohistochemistry of thyroid and thymic neoplasia, revisiting how his special insight is often guided by the work of the early masters of morphology, and how his mentorship of others has helped shaped academic surgical pathology practice, perhaps we can get a glimpse through that lens.

Diagnostic electron microscopy and the influence of Dr. Juan Rosai

Transmission electron microscopy (TEM) was introduced by Ruska and Knoll as a laboratory technique in 1933. Thereafter, several decades passed before the methods required for its optimal implementation were fully developed. Early uses of TEM were in Botany, rather than in Medicine; however, isolated publications did catalog the ultrastructural characteristics of several individual human tumor types. Finally, in 1968, Rosai and Rodriguez authored an important article, introducing the concept that TEM could be used for the differential diagnosis of histologically similar neoplasms. This publication heralded the steadily increasing application of TEM in anatomic pathology over the following decade, including continuing contributions by Dr. Juan Rosai. This brief review summarizes his influence on clinical electron microscopy, and lists some of the lesions for which that procedure is still a useful means of analysis.

An Overview of the Thyroid Gland and Thyroid-Related Deaths for the Forensic Pathologist

The thyroid gland is a butterfly-shaped organ situated in the anterior neck whose functions have system-wide effects. Thyroid diseases represent some of the most commonly encountered endocrine disorders and therefore are commonly encountered at the time of autopsy. Knowing how the gland functions and the effects it may have on vital organs is important when determining the cause of death and significant contributory conditions. Endocrine-related deaths may be anatomically subtle, therefore histologic examination, review of medical records, and selected postmortem testing must be performed to correctly identify and document their presence. For this reason, it is recommended that pathologists consider regularly examining the thyroid gland histologically, particularly on decedents where no apparent anatomic cause of death is identified after the autopsy. This article provides an in-depth review of the thyroid gland, thyroid hormones, and thyroid diseases, including potential thyroid-related deaths and incidental autopsy findings.