Efficacy and safety of larotrectinib in patients with TRK fusion-positive thyroid carcinoma

Molecular Landscape and Therapeutic Strategies in Pediatric Differentiated Thyroid Carcinoma

There has been significant progress in understanding the molecular landscape of pediatric differentiated thyroid carcinoma (DTC) over the past 2 decades. Classification of pediatric DFC into 3 tiers, RAS-like mutant, BRAF mutant, and kinase fusions, accurately reflects an increasing risk for invasive behavior, including regional and distant metastasis. In clinical practice, somatic oncogene testing for nodules with indeterminate cytology per the Bethesda System for Reporting Thyroid Cytopathology provides objective data to optimize surgical planning. In addition, knowledge of the somatic oncogene for widely invasive carcinomas allows for incorporation of oncogene-specific inhibitory therapy both in the adjuvant and neoadjuvant setting. In the present review, we review the risk factors, clinical presentation, and evaluation of pediatric DTC, highlighting the correlation among ultrasound features, cytology, and oncogenic driver of the tumor. We subsequently propose an integrated, multimodal approach that can be used to improve diagnostic accuracy and reliability for preoperative planning as well as identify and discuss which pediatric patients may benefit from systemic oral targeted therapy.

The 2024 revised clinical guidelines on the management of thyroid tumors by the Japan Association of Endocrine Surgery

The Japan Association of Endocrine Surgery published the first edition of the "Clinical guidelines on the management of thyroid tumors" in 2010 and the revised edition in 2018. The guideline presented herein is the English translation of the revised third edition, issued in 2024. The aim is to enhance health outcomes for patients suffering from thyroid tumors by facilitating evidence-based shared decision-making between healthcare providers and patients, as well as standardizing the management of thyroid tumors. The focus is on adult patients with thyroid tumors, addressing clinically significant issues categorized into areas such as an overview of the diagnosis and treatment of thyroid nodules, treatment strategies by histological type, radioactive iodine therapy, treatment of advanced differentiated carcinoma, pharmacotherapy, and complications and safety management associated with thyroid surgery. Thirty-two clinical questions were established in these areas. Following a comprehensive search of the literature and systematic review to evaluate the overall evidence, we aimed to present optimal recommendations by considering the balance of benefits and harms from the patient's perspective. We integrated evidence and clinical experience to determine the "Certainty of evidence" and "Strength of recommendations". Based on these, we illustrated overall flows of care as "Clinical algorithms". Necessary background knowledge of diseases and established clinical procedures for understanding the recommendations are presented in "Notes", while information that may be clinically useful but for which evidence remains insufficient is included in "Columns", based on the current state of evidence. Finally, future challenges for the next revision are presented as "Future research questions".

Paediatric Thyroid Carcinoma: The Genetic Revolution and Its Implications for Therapy and Outcomes

Background: The understanding of the molecular basis of paediatric thyroid carcinoma has expanded rapidly in the last decade. Most carcinomas are associated with de novo somatic gene alterations that confer distinct clinicopathological characteristics. In comparison to adults, paediatric carcinomas are less commonly associated with point mutations and more commonly with gene fusions, which are characterised by more-invasive disease. Cancer predisposition genes play an important role in a small percentage of tumours, and the family history and the recognition of other syndromic features are key to identifying these patients. Molecular testing platforms for clinical use have been developed and validated in adults, and their use is becoming established in the management of indeterminate thyroid nodules, where they significantly reduce the rates of diagnostic lobectomy. Paediatric data are more limited than adult data, and the role of molecular testing in paediatric thyroid carcinoma management is evolving. Methods: This review describes the current knowledge of molecular alterations in paediatric thyroid carcinomas, evidence supporting molecular testing in clinical practice, and future directions for research. Results and Conclusions: A molecular diagnosis enables the use of molecularly targeted therapies for children and adolescents with advanced or radioiodine-refractory disease. There is also great potential for molecular testing to improve the accuracy of the risk-stratification of paediatric thyroid nodules, reducing surgical intervention and complications without negatively impacting outcomes, and data to support such an approach are emerging.

Molecular oncology of iodine refractory thyroid cancer current therapies and perspective

Thyroid cancer (TC) is the most common endocrine malignancy. Most patients will be treated and cured by surgery but a low percentage will develop advanced disease. The treatment of advanced disease is at first the use of radioiodine treatment in differentiated cancer then at progression will rely on molecular alterations and consequently in targeted treatments. In this review, we will explore the most frequent molecular alterations of each histological subtype: differentiated thyroid cancer (DTC), anaplastic thyroid cancer (ATC), medullary thyroid cancers (MTC) and clinically tested and approved treatment. We will also report the clinical and preclinical perspective in this field.

Recent Advances in Diagnostics and Therapeutics for Paediatric Thyroid Cancer

PURPOSE OF REVIEW

Paediatric thyroid cancer management traditionally relied on extrapolation from adult data and, despite good survival outcomes, often involved extensive surgical approaches and radioactive iodine (RAI) therapy with potentially life-long complications. Increasing understanding of paediatric diagnostic techniques, molecular tumour drivers and targeted therapies will allow a more nuanced, disease-specific comprehensive model of care. This review summarises recent developments in paediatric thyroid cancer biology, diagnosis and models of care.

METHODS

Review of relevant literature from the last 5 years to inform a narrative summary by a multidisciplinary team of clinician experts in paediatric thyroid cancer management.

FINDINGS

Standardised risk scoring systems will likely improve the objectivity and accuracy of paediatric thyroid nodule risk stratification on ultrasound, but further studies are needed to validate these. Identification of somatic and germline gene variants is playing a rapidly increasing role in paediatric thyroid cancer diagnosis and planning of surgical approaches and neoadjuvant and adjuvant therapies. There is growing recognition that lobectomy may achieve comparable outcomes, with reduced risk of complications, to total thyroidectomy in patients with low-risk disease. Molecularly targeted therapies are now available for the management of advanced disease as an adjuvant, and likely neo-adjuvant, therapy for medical debulking of large tumours and resensitisation of RAI-resistant disease.

CONCLUSIONS

The management pathways for paediatric thyroid cancer are rapidly evolving due to the increasing availability of paediatric-specific data. As management options become more complex, interdisciplinary collaboration and shared decision-making are ever more important.

Concordance of BRAF V600E mutation between immunohistochemistry and genomic testing for thyroid cancer

BACKGROUND

BRAF V600E mutation is a significant therapeutic target for thyroid cancer, including anaplastic thyroid cancer (ATC). Although targeted therapy for this mutation requires genomic testing in Japan, turnaround time (TAT) is often unacceptably long, especially for certain conditions, such as ATC, which is one of the most aggressive cancers. Here, we evaluated concordance between immunohistochemistry (IHC) with a relatively short TAT of a few days and genomic testing in thyroid cancer.

METHODS

Immunohistochemical staining was performed with BRAF (VE1) antibody (Ventana) using the OptiView method on samples already undergoing genomic testing. A pathologist blindly annotated each staining expression with a cut-off of 1% in the cytoplasm. We then calculated the positive percent agreement (PPA), negative percent agreement (NPA), and overall percent agreement (OPA).

RESULTS

We identified 62 samples, including 12 of ATC, that underwent genomic testing using different methods: Oncomine Dx Target Test (ODxTT) (n = 32), MEBGEN BRAF 3 Kit (MEBGEN3) (n = 14), FoundationOne CDx (F1CDx) (n = 13), and GenMineTOP (TOP) (n = 1). Annotation results of IHC were positive for 31, negative for 29, and undeterminable for 2 samples due to low tumor content. PPA, NPA, and OPA were 100%, 91.7%, 96.9% for ODxTT; 100%, 100%, 100% for MEBGEN3; 100%, 80.0%, 93.9% for F1CDx; and incalculable, 100%, 100% for TOP, respectively. Discordance was found in the two undeterminable samples only.

CONCLUSION

Concordance between IHC and genomic testing in assessing BRAF V600E was encouragingly high; its reliability and potentially short TAT should benefit patients, especially those with ATC.

Transcriptome of Anaplastic Thyroid Cancer Reveals Two Molecular Subtypes with Distinct Tumor Microenvironment and Prognosis

Background: Although patients with anaplastic thyroid cancer (ATC) generally have a poor prognosis and there are currently no effective treatment options, survival and response to therapy vary between patients. Genomic and transcriptomic profiles of ATC have been reported; however, a comprehensive study of the tumor microenvironment (TME) of ATC is still lacking. This study aimed to elucidate the TME characteristics associated with ATC and their prognostic implications. Methods: We analyzed bulk RNA transcriptomic data from 1,634 samples-including 476 normal thyroid tissues, 25 benign thyroid adenomas, 340 RAS-like and 719 BRAFV600E-like differentiated thyroid cancers (DTC-R and DTC-B, respectively), and 74 ATCs. We assessed the TME and molecular characteristics of these thyroid cancer subtypes using deconvolution analysis. Results: The TME of ATC was characterized by a high abundance of immune cells and fibroblasts and a low abundance of epithelial cells compared to other thyroid histologies. During its malignant evolution, ATC exhibited an ecotype more closely related to DTC-B than RAS-like DTC (DTC-R). Furthermore, we identified two distinct molecular subtypes within ATC with significant differences in their TMEs. We termed the subtype with increased immune cells and fibroblasts as ATC-immune-fibroblast (ATC-IF) and the subtype with elevated epithelial and endothelial cells as ATC-epithelial-endothelial (ATC-E). The ATC-IF group had worse disease-specific survival (log-rank p = 0.035), higher ERK scores, and lower thyroid differentiation scores than the ATC-E group. While both ATC subtypes had elevated immune cells and fibroblasts compared to DTC-R and DTC-B, this increase was more pronounced in ATC-IF, with a marked rise in myeloid lineage cells and promigratory fibroblasts. Immune checkpoint gene expression and epithelial-mesenchymal transition scores were significantly higher in the ATC-IF group than in the ATC-E group. Conclusion: ATC shows a TME distinct from that of DTC and can be further divided into two molecular subtypes-each with its own unique TME. The ATC-IF group, with a poorer prognosis and higher ERK score, is enriched in immune cells and fibroblasts, which may represent potential therapeutic targets.

Anticancer drug therapy for anaplastic thyroid cancer

Anaplastic thyroid cancer is one of the rarest subtypes of thyroid cancer, accounting for only 1-2% of all thyroid cancer cases. It is also one of the most aggressive: prognosis remains dismal and the disease-specific mortality rate is close to 100%. This rarity has markedly limited the availability of prospective trial results, and no standard chemotherapeutic option for unresectable or metastatic anaplastic thyroid cancer has yet been established. Nevertheless, combination therapy with a BRAF inhibitor and MEK inhibitor has shown encouraging efficacy in patients with BRAF V600E-mutated anaplastic thyroid cancer. Other novel treatments such as immune checkpoint inhibitors have also shown promising results. Owing to these therapeutic advances, the prognosis of anaplastic thyroid cancer appears to be gradually improving. However, further development of novel treatments for this rare malignancy requires the development of substantial infrastructure for international collaborative study.

Analysis of immediate 503 thyroid carcinoma deaths: trend of single institution in 2005-2024

Background

This study aimed to investigate the changes in histological types and causes of death associated with thyroid carcinoma (TC) before and after the introduction of systemic drug therapy.

Methods

The records of 503 deceased patients treated for TC and with death from TC between January 2005 and June 2024 were reviewed in this retrospective cohort study. Multivariate logistic regression was applied to assess whether the number of patients with anaplastic TC (ATC) at diagnosis and the number of local-related deaths changed before and after the introduction of lenvatinib (i.e. 2005-2014 vs 2015-2024).

Results

Of the 503 patients, 157 (31%) had ATC, 253 (50%) had papillary TC (PTC), 67 (13%) had follicular TC (FTC), 17 (3%) had poorly differentiated TC, and nine (2%) had medullary TC. Respiratory insufficiency was the most common fatal condition, occurring in 192 cases (38%), followed by local-related death in 98 cases (19%) and brain-related conditions in 22 cases (4%). We found no difference in the frequency of patients with ATC at diagnosis (32 vs 30%; P-value = 0.772) and the frequency of local-related deaths (19 vs 20%; P-value = 0.736) between 2005-2014 and 2015-2024. These findings were supported by multivariate logistic regression models that adjusted for other covariates (adjusted P-value = 0.436 and 0.353, respectively).

Conclusions

ATC, including anaplastic transformation from PTC and FTC, still accounts for approximately 40% of thyroid cancer deaths after the introduction of systemic drug therapy. Respiratory insufficiency is the most common immediate cause of death.

[Update on anaplastic thyroid cancer-What is relevant for surgeons?]

Anaplastic thyroid cancer (ATC) is the rarest but also the most aggressive carcinoma entity of the thyroid gland. In recent years, treatment options have evolved and molecular oncological treatment approaches have gained in importance. The neoadjuvant use of these innovative therapies has the potential to convert previously unresectable tumors into a resectable state, thereby expanding surgical options and significantly improving the prognosis of patients. This article provides recommendations relevant for surgery for the diagnostics and treatment of ATC, based on a current literature review and the discussions of the S3 guideline conferences.

Chinese management guidelines for radioactive iodine-refractory differentiated thyroid cancer (2025 edition)

PURPOSE

Radioactive iodine-refractory differentiated thyroid cancer (RAIR-DTC) has become a challenge in clinical practice, particularly in China with a high incidence and undesirable survival outcome. Since the publication of first China consensus on the diagnosis and treatment of RAIR-DTC in 2019, significant and rapid advances have occurred in the field both in China and internationally. This guideline aims to inform Chinese clinicians, researchers, patients, and health policy makers on the latest evidence and recommendations, to further standardize the clinical diagnosis and treatment of RAIR-DTC.

METHODS

The structured clinical questions addressed in this guideline were derived from clinical diagnostic and treatment processes, with references to study, prior guidelines, expert consensus, and systematic reviews, etc. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used for quantitative and qualitative evaluation of the evidence. The editorial process was completely independent of the guideline development group.

RESULTS

The guideline addressed 26 clinical questions and formed 35 recommendations. In this guideline, the definition criteria for RAIR-DTC was optimized, prediction and identification was based on evidence including molecular testing, dynamic biochemical changes, and multimodal imaging. Comprehensive pre-treatment clinical evaluation was emphasized and tailored for individualized decision-making. The combination of systematic therapy and surgery, and the redifferentiation followed by RAI therapy were also reviewed and updated. Molecular imaging plays a unique role in the pre-assessing and therapeutic response evaluation for RAIR-DTC.

CONCLUSIONS

We have updated and developed evidence-based recommendations with the aim of providing scientific, rigorous, and comprehensive guidance for the clinical diagnosis and treatment of RAIR-DTC patients in China. We hope to share our guideline with colleagues out of China, with the expectation of further comments and suggestions.

Next-Generation Immunohistochemistry in Thyroid Neoplasm: A Practical Review on the Applications in Diagnosis and Molecular Classification

An integrative histologic and molecular classification of thyroid tumors has become clinically relevant due to the potential role in risk stratification and selection of targeted therapy. In this review, we discuss the applications of six "next-generation" immunohistochemical markers, namely BRAF V600E (clone VE1), RAS Q61R (clone SP174), pan-TRK (clone EPR 17341), ALK (clones 5A4 or D5F3), PTEN, and β-catenin in the pathologic diagnosis and molecular classification of thyroid tumors. These biomarkers allow the in situ examination of tumor tissue and assist in the diagnosis and pathologic staging by highlighting tumor border and patterns of invasion, identifying isolated tumor cells in lymph nodes, distinguishing lymph node metastasis from benign intranodal thyroid inclusions, and diagnosing multicentric thyroid carcinomas with discordant molecular drivers. Furthermore, it can identify specific thyroid neoplasms that may occur sporadically or may be associated with hereditary syndromes. The next-generation immunohistochemistry provides a novel solution to challenging issues in thyroid pathology and fast turn-around time for accurate molecular classification and further guidance of therapeutic management.

A visualization analysis of global research trends in targeted therapies for thyroid carcinoma (2013-2023)

This study aims to analyze and identify primary research trends in targeted therapy for thyroid carcinoma (TC). It seeks to provide a factual foundation for researchers, as TC often presents with advanced stages and aggressive subtypes, leading to unfavorable clinical outcomes. The evolution of targeted therapies introduces promising treatment possibilities, necessitating a bibliometric analysis to better understand the current state and trends in this field. A comprehensive bibliometric analysis was conducted using data from the Web of Science Core Collection (WOSCC). Advanced search queries established a literature database, and the analysis was performed using tools such as VOSviewer, CiteSpace, Tableau, and Microsoft Excel. The study focused on publications from 2013 to 2023, examining patterns, geographical contributions, institutional output, and influential journals. The analysis identified 763 publications on TC targeted therapy during the study period, with significant contributions from the United States, China, and Italy, and the United States leading in output. Research activity peaked in 2021, showing overall fluctuating growth. Key contributing institutions included the University of Texas MD Anderson Cancer Center and the University of Pisa. Notable journals, such as Cancers and Thyroid, were among the most cited, underscoring their impact in the field. The study highlighted an increase in global research output and robust international collaborations, particularly among the leading contributing countries. This bibliometric analysis provides a comprehensive overview of significant contributions and trends in targeted therapy research for TC. It identifies key development processes and research hotspots, offering valuable insights to guide future research directions. The findings aim to stimulate further studies and foster advancements in this critical area of oncology.

The value of preoperative molecular testing in the management of Bethesda V and Bethesda VI thyroid tumors

The incidence of thyroid cancer has increased over recent years due to the fact that several diagnostic tools, such as neck ultrasound and fine-needle aspiration, are being ever more widely adopted. Lately, another modality which might provide significant information preoperatively on the aggressiveness of a thyroid tumor, its prognosis, and its recurrence rate is molecular testing. We reviewed the literature with regard to the role of preoperative molecular testing in patients with Bethesda V and Bethesda VI thyroid nodules and its impact on choice of the optimal treatment strategy. Several molecular mutations and alterations are associated with thyroid cancer and its biological behavior, such as BRAF-V600E, RET, and TERT promoter. Although the value of preoperative molecular testing for indeterminate nodules (Bethesda III and Bethesda IV) have been analyzed in numerous studies, the impact of preoperative molecular testing on Bethesda V and Bethesda VI thyroid nodules is not adequately described in the current literature. The preoperative recognition of specific molecular mutations, such as BRAFV600E and TERT promoter mutation, might provide more individualized management for thyroid cancer patients by altering the surgical approach and the extent of surgery for patients diagnosed with a more aggressive or iodine-resistant subtype of thyroid cancer.Thyroid cancer is characterized by multiple genetic mutations and alterations and, as a result, preoperative molecular testing of malignant nodules could be a very useful tool for surgeons, enabling them to decide on the most appropriate surgical approach for each patient.

Modern Therapeutic Approaches in Anaplastic Thyroid Cancer: A Meta-Analytic Review of Randomised and Single Arm Studies on Efficacy and Survival

Background: Meta-analyses aimed to assess the effectiveness and safety of targeted and contemporary therapies utilised in locally advanced and metastatic anaplastic thyroid cancer (ATC). Methods: Employing PRISMA and MOOSE guidelines, PubMed, Scopus, Cochrane Library and Web of Science were explored from the inception of targeted therapy until December 2024. A meta-analysis was performed to evaluate the effectiveness, toxicity and survival outcomes of various mutationally directed agents, chemotherapy and radiotherapy in locally advanced/metastatic ATC cases. Results: A total of 47 studies (26 prospective phase II trials and 21 retrospective studies) involving 980 patients met the inclusion criteria. The pooled results showed an overall response rate (ORR) of 29.7% (95% CI: 25.4-34.2%; I2 = 42.4%; p < 0.0001). A total of 49.9% deaths were reported, although a significant number remained alive compared to baseline (mean difference [MD]: 2.07, 95% CI: 1.90-2.24; I2 = 88.6%; p < 0.0001). The pooled median progression-free survival (PFS) was 5.4 months (95% CI: 4.0-6.7 months; I2 = 97.9%; p < 0.0001). Dabrafenib/trametinib (DT) with and without pembrolizumab and lenvatinib plus pembrolizumab (LP) were associated with higher ORR rates and improved OS and PFS. About 51.% of studies mentioned bio-marker analysis (BRAFV600 [14.7%], PDL1 [9.2%], RAS [1.1%], PIK3CA [1.0%] and NTRK1/3 [0.7%]). Toxicity was reported in 94.7% of patients. Conclusions: This meta-analysis found that DT could be a promising first-line treatment option for BRAFV600-mutated ATC, with or without immunotherapy. Alternatively, LP shows potential in BRAFV600 wild-type and PDL1-overexpressing cases. Routine biomarker analysis remains critical for optimising ATC management strategies.

NTRK Fusion-Positive Thyroid Carcinoma: From Diagnosis to Targeted Therapy

PURPOSE

Neurotrophic tropomyosin receptor kinase (NTRK) fusions may act as an oncogenic driver in thyroid carcinomas. Given their low frequency, clinical, pathological, and molecular data on these patients and their responses to targeted therapies are limited.

METHODS

This is an observational retrospective study conducted at a single high-volume cancer center in the United States. Data were retrospectively collected from medical records.

RESULTS

We included 65 patients (37 adult, 28 pediatric) with an NTRK fusion-positive thyroid carcinoma (24 NTRK1, 41 NTRK3), of which 54 were papillary thyroid carcinomas (PTC), four poorly differentiated thyroid carcinomas (PDTC), and seven anaplastic thyroid carcinomas (ATC). In PTC, an extensive follicular growth pattern was seen in 22 (41%) patients. In adults, NTRK3 fusions were 3 times more frequent (nine NTRK1, 28 NTRK3), whereas in pediatric patients their frequencies were similar (15 NTRK1, 13 NTRK3; P = .021). In patients with PDTC/ATC treated with larotrectinib, we detected four emergent solvent front mutations (three NTRK3 G623R, one NTRK1 G595R) causing resistance to drug and disease progression. Three of them (two ATC, one PDTC) received second-line selitrectinib on a clinical trial. Partial responses were seen in all three patients, but both patients with ATC progressed within a year.

CONCLUSION

NTRK1/3 fusions are seen in PTC, PDTC, and ATC, and a follicular growth pattern was observed in a high proportion of cases. In patients treated with larotrectinib, NTRK solvent front mutations are the main resistance mechanism, frequently occurring in PDTC/ATC. Responses to single-agent TRK inhibitor are short-lived in patients with ATC; thus, these drugs should be used with caution in this population.

Hidden in Plain Sight: Incidental Diagnosis of Metastatic Papillary Thyroid Microcarcinoma Without Radiologically Apparent Thyroid Tumor

Background/Objective

Papillary thyroid cancer (PTC) is considered the most common form of thyroid cancer. Papillary thyroid microcarcinomas (PTMCs) are defined as papillary carcinomas that are <1 cm and are often identified on surgical pathology but may be missed by ultrasound imaging.

Case Report

Our case describes a 24-year-old woman who initially presented with a right lateral neck lump. This was thought to be a lipoma, and no workup was performed until it began to grow during pregnancy 3 to 4 years after initial presentation. The patient underwent excision with findings of a level 5B lymph node with pathology consistent with PTC, follicular variant. Neck ultrasound performed in an imaging center and in our clinic did not reveal thyroid nodules or abnormal appearing lymph nodes. Solid tumor profiling assay identified a neurotrophic tropomyosin receptor kinase (NTRK)-3 fusion: ETV6(4)-NTRK3(14) mutation.

Discussion

PTMCs are identified with increased frequency due to improved ultrasound imaging and fine needle aspiration techniques. PTMCs are often associated with a benign course and are rarely metastatic. There has been growing interest in NTRK fusion mutations in PTC that has been associated with an increased risk of metastasis.

Conclusion

This case is unusual in that multiple cervical nodal metastases were present even without a sizable primary thyroid tumor. Although more studies are needed to elucidate the clinical and prognostic significance of NTRK fusion mutations in PTMC, their response to tropomyosin receptor kinase inhibitors may represent a future pathway for treatment.

NTRK fusion promotes tumor migration and invasion through epithelial-mesenchymal transition and closely interacts with ECM1 and NOVA1

BACKGROUND

The NTRK fusion gene is a rare cancer driver and a typical representative "diamond mutation". Its unique role in tumor progression is highly important for the clinical diagnosis and treatment of patients with tumors. We searched for NTRK fusion-positive patients in our hospital. As of August 2022, a total of 8 patients were affected. We discovered that NTRK fusion was associated with enhanced tumor invasion and migration ability. Previous reports also support this finding, but its underlying mechanism has not been elucidated.

METHODS

We undertook a comprehensive exploration of the correlations between NTRK fusions and tumor invasion as well as migration by analysing clinical data, performing bioinformatics analysis via public databases, and conducting in vitro cell experiments.

RESULTS

We ascertained that within the thyroid cancer (THCA) dataset and the pancancer dataset, ECM1 and NOVA1 were coexpressed with NTRKs. Additionally, they demonstrated a significant association with the activity of the epithelial‒mesenchymal transition (EMT) pathway. Furthermore, these genes are overexpressed in various cancers and are associated with advanced clinical stage and increased aggressiveness. Our in vitro study revealed that larolutinib potentially inhibited the invasion and metastasis ability of NTRK-fused cells. Interestingly, contrary to previous findings, the repression of ECM1 increased the migration and invasion ability of NTRK-fused tumor cells.

CONCLUSIONS

NTRK fusion tumors present heightened migratory and invasive potential in clinical settings. Further experiments confirmed the significant inhibitory effects of TRK inhibitors on the migration and invasion abilities of these cells. There is a complex relationship between ECM1, NOVA1 and NTRK fusion; however, further research is needed to determine whether NTRK fusion promotes tumor metastasis through these two genes.

Anaplastic thyroid cancer: A review of recent evidence and summary of an Australian institutional protocol

Anaplastic thyroid cancer (ATC), a rare and highly aggressive malignancy, is characterized by an exceptionally poor prognosis, where the majority of patients present with extensive local invasion and/or distant metastases. 20-30% of ATCs harbor the BRAF-V600E mutation. Neoadjuvant BRAF-targeted therapy may have the potential to downstage and facilitate surgical resection for patients with locally advanced and unresectable primary tumors with BRAF mutation and may convey a survival advantage in those with metastatic disease. There is emerging evidence to support the use of other targeted agents, including multikinase inhibitors, as well as the incorporation of immunotherapy into the treatment regimen. Rapid molecular and pathological diagnosis and expert multidisciplinary discussion at specialized treatment centers are critical to expedite investigations and initiate treatment for this complex and rapidly progressive disease.

Multidisciplinary Canadian consensus on the multimodal management of high-risk and radioactive iodine-refractory thyroid carcinoma

Most follicular cell-derived differentiated thyroid carcinomas are regarded as low-risk neoplasms prompting conservative therapeutic management. Here, we provide consensus recommendations reached by a multidisciplinary group of endocrinologists, medical oncologists, pathologists, radiation oncology specialists, a surgeon and a medication reimbursement specialist, addressing more challenging forms of this malignancy, focused on radioactive iodine (RAI)-resistant or -refractory differentiated thyroid carcinoma (RAIRTC). In this document we highlight clinical, radiographic, and molecular features providing the basis for these management plans. We distinguish differentiated thyroid cancers associated with more aggressive behavior from thyroid cancers manifesting as poorly differentiated and/or anaplastic carcinomas. Treatment algorithms based on risk-benefit assessments of different multimodal therapy approaches are also discussed. Given the scarcity of data supporting management of this rare yet aggressive disease entity, these consensus recommendations provide much needed guidance for multidisciplinary teams to optimally manage RAIRTC.

SEOM-GETNE-TTCC Clinical guideline thyroid cancer (2023)

Thyroid cancer (TC) represents 3% of global cancer incidence. Recent changes have optimized treatment decisions based on risk assessment, molecular profiling, and imaging assessment, leading the development of targeted agents that have modified the natural history of this disease. This increasing complexity on treatment options requires careful assessment at the different stages of the disease to provide the most suitable approach from diagnosis to long-term follow-up. This guideline aims to offer a comprehensive and practical overview on the current status and last updates of TC management.

Systemic treatments for radioiodine-refractory thyroid cancers

Differentiated thyroid cancers (DTCs) constitute the primary histological subtype within thyroid cancer. Due to DTCs' distinctive radioiodine (RAI) uptake mechanism, standard treatment involving surgery, with or without adjunctive therapy using RAI and levothyroxine inhibition, typically yields favorable prognoses for the majority of patients with DTCs. However, this favorable outcome does not extend to individuals with decreased RAI uptake, termed radioiodine-refractory thyroid cancers (RAI-RTCs). Recent research has revealed that the genetic mutations and gene rearrangements affecting sites such as RTKs, RAS, BRAF and TERTp lead to structural and functional abnormalities in encoded proteins. These abnormalities aberrantly activate signaling pathways like the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-hydroxykinase (PI3K) signaling pathways, resulting in thyroid cells dedifferentiation, sodium/iodide symporter (NIS) dysfunction, and consequent the RAI-refractory nature of DTCs. Targeted therapy tailored to mutations presents a promising avenue for the treatment of RAI-RTCs. Lenvatinib and sorafenib, multi-kinase inhibitors, represent the standard first-line systemic treatment options, while cabozantinib is the standard second-line treatment option, for this purpose. Furthermore, ongoing clinical trials are exploring selective kinase inhibitors, immune checkpoint inhibitors, and combination therapies. Notably, numerous clinical trials have demonstrated that selective kinase inhibitors like BRAF, MEK and mTOR inhibitors can restore RAI uptake in tumor cells. However, further validation through multicenter, large-sample, double-blinded randomized controlled trials are essential. Enhanced treatment strategies and innovative therapies are expected to benefit a broader spectrum of patients as these advancements progress.

Aggressive Types of Malignant Thyroid Neoplasms

Differentiated thyroid cancer (DTC) includes many subtypes, which demonstrate favorable to aggressive behavior. During the past decades, efforts have been made to describe aggressive thyroid cancers. Within DTC, aggressive variants constitute rare entities with unique histopathological features and compromised survival, as local and distant metastatic disease is frequent. In recent years, the distinct category of poorly differentiated thyroid cancer was introduced in 2004 and the type of differentiated high-grade thyroid carcinoma was recently added in the 2022 WHO classification of thyroid neoplasms. Finally, anaplastic thyroid cancer exhibits a rapid, resistant to therapy, progression and confers the shortest survival. In this review, we will present the characteristics of these thyroid cancer types and also discuss the treatment, management, and follow-up of these difficult cases. Emphasis was given to recent bibliography of the last decade.

Le cancer thyroïdien différencié réfractaire à l’iode : quelle prise en charge en 2024 ?

TREATING RADIO-IODINE REFRACTORY DIFFERENTIATED THYROID CANCER IN 2024: About 5 to 10% of patients with differentiated thyroid cancer (DTC) have advanced tumors at presentation or recurrence, with invasive cervical disease and/or distant metastases that cannot be effectively treated by conventional treatment, i.e. thyroid surgery and radioactive iodine. These DTC cases are defined as refractory to radioiodine (RAIR) and require expert multidisciplinary management. In France, patients are referred to centers of the ENDOCAN-TUTHYREF Network. This review summarizes current management of RAIR DTC patients and therapeutic options available in 2024. We discuss following topics : epidemiological data, modalities of local ablative treatment for selected metastatic lesions, molecular tests to be performed, optimum timing for initiating systemic therapy, choice of first-line treatment among validated tyrosine kinase inhibitors (TKIs), alternative targeted treatments (including selective TKIs adapted to the molecular profile, some of which can redifferentiate and restore radioactive iodine uptake), proactive management of TKI side effects, and finally give an overview of systemic strategies. Management of RAIR DTC is still challenging but substantial progress has been made over the last decade that has significantly improved outcome for these more aggressive thyroid cancer.

Quelles avancées dans la prise en charge du carcinome anaplasique de la thyroïde en 2024 ?

LATEST DEVELOPMENTS IN ANAPLASTIC THYROID CARCINOMA MANAGEMENT IN 2024: Anaplastic thyroid carcinomas (ATCs) represent a rare and undifferentiated form of thyroid cancer with a poor prognosis, typically marked by a median overall survival of four to ten months. However, recent advances have shown improvements due to the more systematic application of molecular testing, targeted therapies, and immunotherapy, alongside the establishment of rapid specialized care protocols in expert centers. Clinically, ATCs often present as a rapidly enlarging cervical mass originating from the thyroid, causing neck, pain and tenderness, dyspnea and dys-phagia, and associated lymphadenopathy, typically in elderly patients. Diagnostic confirmation requires an urgent biopsy, reviewed by a pathologist within the TUTHYREF-path network, with a mandatory search for BRAFV600E molecular alterations. Following diagnosis, care coordination is expedited within an expert center of the ENDOCAN-TUTHYREF network whenever feasible. Initial surgery is rarely an option due to frequent loco-regional cervical invasion. A multimodal treatment approach is essential: BRAF/MEK inhibitors (dabrafenib/trametinib) in cases of BRAFV600E mutation, or chemotherapy in the absence of a molecular target, combined with radiotherapy and, potentially, surgery if the disease becomes resectable following induction therapy. PD-1/PD-L1 targeted immunotherapy, either alone or in combination with targeted therapies, has shown potential to extend survival in some patients; however, predictive biomarkers and the optimal sequencing of immunotherapy (whether as induction and/or maintenance) require further clarification and may vary depending on the clinical context.

Brain Metastases in Differentiated Thyroid Cancer: Clinical Presentation, Diagnosis, and Management

Background: Brain metastases (BM) are the most common intracranial neoplasms in adults and are a significant cause of morbidity and mortality. The brain is an unusual site for distant metastases of thyroid cancer; indeed, the most common sites are lungs and bones. In this narrative review, we discuss about the clinical characteristics, diagnosis, and treatment options for patients with BM from differentiated thyroid cancer (DTC). Summary: BM can be discovered before initial therapy due to symptoms, but in most patients, BM is diagnosed during follow-up because of imaging performed before starting tyrosine kinase inhibitors (TKI) or due to the onset of neurological symptoms. Older male patients with follicular thyroid cancer (FTC), poorly differentiated thyroid cancer (PDTC), and distant metastases may have an increased risk of developing BM. The gold standard for detection of BM is magnetic resonance imaging with contrast agent administration, which is superior to contrast-enhanced computed tomography. The treatment strategies for patients with BM from DTC remain controversial. Patients with poor performance status are candidates for palliative and supportive care. Neurosurgery is usually reserved for cases where symptoms persist despite medical treatment, especially in patients with favorable prognostic factors and larger lesions. It should also be considered for patients with a single BM in a surgically accessible location, particularly if the primary disease is controlled without other systemic metastases. Additionally, stereotactic radiosurgery (SRS) may be the preferred option for treating small lesions, especially those in inaccessible areas of the brain or when surgery is not advisable. Whole brain radiotherapy is less frequently used in treating these patients due to its potential side effects and the debated effectiveness. Therefore, it is typically reserved for cases involving multiple BM that are too large for SRS. TKIs are effective in patients with progressive radioiodine-refractory thyroid cancer and multiple metastases. Conclusions: Although routine screening for BM is not recommended, older male patients with FTC or PDTC and distant metastases may be at higher risk and should be carefully evaluated for BM. According to current data, patients who are suitable for neurosurgery seem to have the highest survival benefit, while SRS may be appropriate for selected patient.

Nouveautés en pathologie thyroïdienne : classification OMS 2022, système Bethesda 2023, biologie moléculaire et testing moléculaire

ADVANCES IN THYROID PATHOLOGY

WHO CLASSIFICATION 2022, BETHESDA SYSTEM 2023, MOLECULAR BIOLOGY AND MOLECULAR TESTING: Thyroid pathology has experienced significant advances with the publication of the 5th edition of the World Health Organization classification of endocrine tumors in 2022 and the third edition of the Bethesda system for thyroid cytopathology in 2023. At the same time, the availability of next-generation sequencing data coupled with numerous translational research projects have considerably increased our knowledge of the genomics and mechanics of thyroid cancers, enabling us to refine prognosis and propose new targeted therapies. In this review, we will take up the main new features of the WHO 2022 and Bethesda 2023 classifications, as well as molecular biology findings, with an emphasis on the practical implications for clinicians.

GNA15 facilitates the malignant development of thyroid carcinoma cells via the BTK-mediated MAPK signaling pathway

G protein subunit alpha 15 (GNA15) is recognized as an oncogene for some cancers, however, its role in thyroid carcinoma (TC) is elusive and is investigated in this study. Concretely, bioinformatics was employed to analyze the GNA15 expression profile in TC. The effect of GNA15 on TC cell functions was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, and Transwell assays. Expressions of extracellular regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 were determined using Western blot. The involvement of Bruton tyrosine kinase (BTK) in the mechanism of GNA15 was investigated by BTK knockdown and rescue assay. GNA15 presented an overexpression pattern in TC samples, which facilitated the viability, proliferation, migration, and invasion of TC cells; GNA15 silencing led to converse results. Ratios of p-ERK/ERK, p-JNK/JNK, and p-p38/p38 were upregulated by GNA15 overexpression. The BTK deficiency weakened the aforementioned behaviors of TC cells and blocked the MAPK signaling pathway, however, these effects were counteracted by GNA15 overexpression. Collectively, GNA15 contributes to the malignant development of TC cells by binding to BTK and thus activating the MAPK signaling pathway.

Single-Institution Experience of Larotrectinib Therapy for Patients With NTRK Fusion-Positive Thyroid Carcinoma

Context

The real world efficacy and tolerabiltiy of NTRK inhibitor larotrectinib has not yet been reported in the literature although trial data has shown promising results.

Objective

We report a retrospective analysis of patients with thyroid cancer harboring NTRK fusions who underwent treatment with larotrectinib.

Methods

A single-institution, retrospective case series of patients with NTRK fusion-positive thyroid cancers treated with neurotrophic tyrosine receptor kinase (NTRK) inhibitors from January 1, 2007, to January 1, 2023, was performed. This study was conducted at a single academic tertiary referral center. Patients with confirmed NTRK-fusion thyroid cancer who received larotrectinib were included. Larotrectinib was administered in accordance with clinical judgment from oncology providers. The primary end point was progression-free survival (PFS).

Results

Eight patients with NTRK fusion-positive thyroid cancer treated with larotrectinib were identified: 4 with papillary thyroid cancer (PTC) (50%), 3 with poorly differentiated thyroid cancer (PDTC) (38%), and 1 with anaplastic thyroid cancer (ATC) (12%). The median PFS (mPFS) for all patients was 24.7 months (95% CI, 11.3-38.1). mPFS in PTC was higher than PDTC (34.6 months [24.7-48.7 months] vs 17.5 [7.1-21.1 months]; P = .017). The median overall survival (OS) was 43.8 months (29.8-56.8 months) overall. The single patient with ATC had a PFS and OS of 23 months. Two patients remained on treatment/alive at data cutoff, with a duration of response of 33.5 months and a median follow-up of 52 months. Patients achieved 1 complete response (12%), 6 partial responses (75%), and 1 stable disease (12%).

Conclusion

In this single-institution cohort of patients with NTRK fusion-positive thyroid cancer, NTRK inhibition led to an mPFS of 25 months, with survival surpassing historic benchmarks for ATC and PDTC.

The efficacy and safety of antiangiogenesis tyrosine kinase inhibitors in patients with advanced anaplastic thyroid cancer: A meta-analysis of prospective studies

BACKGROUND

The poor prognosis of anaplastic thyroid cancer (ATC) patients is associated with limited effective therapeutic strategies. Multiple antiangiogenesis tyrosine kinase inhibitors (TKIs) have been applied in later-line treatment of ATC; however, the results reported in clinical trials were controversial. In this study, we reconstructed the patient-level data to pooled-analyze the survival data, responses, and adverse events.

METHODS

Online databases (PubMed, Web of Science, Embase, and Cochrane CENTRAL) were searched on September 03, 2023. R software combined with the "metaSurvival" and "meta" packages were used to reconstruct the survival curves and summarize the response rates. The primary endpoints were progression-free survival (PFS) and overall survival (OS). The secondary endpoints were survival rate, objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events.

RESULTS

Six prospective clinical trials involving 140 ATC patients were enrolled. Four types of TKIs (imatinib, pazopanib, sorafenib, and lenvatinib) were included. When advanced ATC patients were treated with the TKIs, the median OS was 4.8 months and the median PFS was 2.6 months. The pooled ORR and DCR were 9% and 53%. Hypertension, decreased appetite, rash, and lymphopenia were the most common grade ≥ 3 treatment-related adverse events.

CONCLUSION

Mono-anitangiogenesis TKI therapy showed limited improvements in treating advanced ATC patients. Combining antiangiogenesis TKI therapy with chemotherapy, radiotherapy, or immunotherapy could be the direction of future studies.

Recent advances in the use of tyrosine kinase inhibitors against thyroid cancer

INTRODUCTION

Oncogenic tyrosine kinases (TK) are enzymes that play a key role in cell growth and proliferation and their mutations can lead to uncontrolled cell growth and development of aggressive cancer. This knowledge has led to the development of new classes of drugs, Tyrosine kinase inhibitors (TKI). They target oncogenic kinases who are associated with advanced radioactive iodine (RAI) refractory TC, which is not able to uptake RAI anymore and/or still grows between consecutive treatments with Iodine 131 (I131).

AREAS COVERED

Since Lenvatinib and Sorafenib approval, several other molecular inhibitors have been studied and then introduced for the treatment of aggressive and refractory thyroid cancer (TC), and, although the development of adverse effects or tumor resistance mechanisms, more and more compounds are still under investigation. The literature search was executed in PubMed and ClinicalTrials.gov to identify relevant articles and clinical trials published until December 2023.

EXPERT OPINION

In the context of clinical trials, driven by the presence of specific molecular mutations or even in the absence of both conditions, systemic therapy TKIs are valuable weapons to be used in patients affected by aggressive forms of TC, waiting for further expansion of the treatment landscape with more efficacious and safer drugs.

Ten years' real-life experience on the use of multikinase inhibitors in patients with advanced differentiated thyroid cancer

PURPOSE

To evaluate objective response rates (ORR), progression-free survival (PFS), and overall survival (OS) associated with tyrosine kinase inhibitors (TKIs) in patients with radioiodine refractory differentiated thyroid cancer (RR-DTC). Additionally, to compare: (i) ORR and PFS among patients treated with lenvatinib and sorafenib; (ii) ORR and PFS among patients receiving lenvatinib as first-line vs. second-line and; (iii) adverse effects (AEs) observed in patients treated with these medications.

METHODS

Retrospective analysis of RR-DTC adult patients treated with TKIs at the Division of Endocrinology, Hospital de Clinicas, University of Buenos Aires (March 2011-November 2023).

RESULTS

Among 43 patients included in the study, 32 received sorafenib (30 as first-line and 2 as second-line), while 29 received lenvatinib (12 as first-line and 17 as second-line). The median PFS and OS for the entire cohort were 32.7 and 39.0 months, respectively. Lenvatinib demonstrated a significantly higher ORR compared to sorafenib (37.9% vs. 9.4%, p = 0.008). However, both drugs exhibited similar median PFS (23.2 vs. 16.0 months, p = 0.419). No significant difference was observed in ORR and PFS between patients receiving first-line vs. second-line lenvatinib. Sorafenib-treated patients experienced higher rates of hand-foot skin syndrome (69% vs. 41%, p = 0.032) and alopecia (25% vs. 3%, p = 0.018), whereas lenvatinib-treated patients had higher rates of proteinuria (31% vs. 0%, p < 0.001) and grade 3 hypertension (31% vs. 9%, p = 0.034).

CONCLUSION

TKIs demonstrated efficacy and tolerability comparable to real-world data in RR-DTC. PFS was not statistically different between sorafenib and lenvatinib. Our study will help guide physicians in making informed decisions regarding treatment sequencing with TKIs in these patients.

Vandetanib in locally advanced or metastatic differentiated thyroid cancer refractory to radioiodine therapy

The VERIFY study aimed to determine the efficacy of vandetanib in patients with differentiated thyroid cancer (DTC) that is either locally advanced or metastatic and refractory to radioiodine (RAI) therapy. Specifically, VERIFY is a randomized, double-blind, multicenter phase III trial aimed to determine the efficacy and safety of vandetanib in tyrosine kinase inhibitor-naive patients with locally advanced or metastatic RAI-refractory DTC with documented progression (NCT01876784). Patients were randomized 1:1 to vandetanib or placebo. The primary endpoint was progression-free survival (PFS). Secondary endpoints included best objective response rate, overall survival (OS), safety, and tolerability. Patients continued to receive randomized treatment until disease progression or for as long as they were receiving clinical benefit unless criteria for treatment discontinuation were met. Following randomization, 117 patients received vandetanib, and 118 patients received a placebo. Median PFS was 10.0 months in the vandetanib group and 5.7 months in the placebo group (hazard ratio: 0.75; 95% CI: 0.55-1.03; P = 0.080). OS was not significantly different between treatment arms. Common Terminology Criteria for Adverse Events (CTCAE) of grade ≥3 were reported in 55.6% of patients in the vandetanib arm and 25.4% in the placebo arm. Thirty-three deaths (28.2%; one related to study treatment) occurred in the vandetanib arm compared with 16 deaths (13.6%; two related to treatment) in the placebo arm. No statistically significant improvement was observed in PFS in treatment versus placebo in patients with locally advanced or metastatic, RAI-refractory DTC. Moreover, active treatment was associated with more adverse events and more deaths than placebo, though the difference in OS was not statistically significant.

Larotrectinib efficacy for liver metastases in papillary thyroid carcinoma patient harboring SQSTM1-NTRK1 fusion

BACKGROUND

Pooled data analysis from three phase I/II larotrectinib clinical trials revealed that larotrectinib demonstrated rapid and durable disease control and a favorable safety profile for patients with neurotrophic-tropomyosin receptor kinase (NTRK) fusion positive thyroid carcinoma. Herein, we report the case of a patient with papillary thyroid carcinoma (PTC) and liver metastases who demonstrated a durable response to treatment with larotrectinib.

CASE PRESENTATION

A 50-year-old female with PTC was referred to our hospital for postoperative observation. Computed tomography (CT) scan was performed to screen for distant metastasis, since thyroglobulin concentration increased gradually, and revealed multiple distant metastases, including multiple liver metastases. Radioactive iodine was administered at a dose of 100 mCi. However, uptake was observed only in the thyroid bed, and distant metastases had no avidity. As liver metastases progressed, lenvatinib (24 mg/day) was initiated after confirmation of liver metastases by liver biopsy 9 years and 1 month after the initial referral to our hospital. Since the multiple metastases became refractory for lenvatinib, the OncoGuide™ NCC Oncopanel System was performed, and the SQSTM1-NTRK1 gene fusion was confirmed. Larotrectinib was subsequently administered at a dose of 200 mg/day. The CT before the initiation of larotrectinib showed multiple liver metastases with a maximum diameter of 48 mm. The first CT evaluation at 1 month after the initiation of larotrectinib treatment showed that the tumor volume was reduced by 28% in the RECIST 1.1 criteria. After 3 months of larotrectinib treatment, a 38% reduction in the tumor volume was achieved as the best clinical response. The only side effect was grade 1 myalgia. At 12 months after the initiation of larotrectinib treatment, none of the lesions had progressed.

CONCLUSIONS

In conclusion, larotrectinib demonstrated effective antitumor activity against liver metastases of PTC, a relatively rare site of distant metastasis. Furthermore, the efficacy of larotrectinib was maintained, even though the patient had a history of multi-tyrosine kinase inhibitor treatment and a relatively infrequent fusion gene, SQSTM1-NTRK1.

Neurotrophic tyrosine receptor kinase gene fusions in adult and pediatric patients with solid tumors: a clinicogenomic biobank and record linkage study of expression frequency and patient characteristics from Finland

BACKGROUND

Neurotrophic tyrosine receptor kinase (NTRK) gene fusions are oncogenic drivers. Using the Auria Biobank in Finland, we aimed to identify and characterize patients with these gene fusions, and describe their clinical and tumor characteristics, treatments received, and outcomes.

MATERIAL AND METHODS

We evaluated pediatrics with any solid tumor type and adults with colorectal cancer (CRC), non-small cell lung cancer (NSCLC), sarcoma, or salivary gland cancer. We determined tropomyosin receptor kinase (TRK) protein expression by pan-TRK immunohistochemistry (IHC) staining of tumor samples from the Auria Biobank, scored by a certified pathologist. NTRK gene fusion was confirmed by next generation sequencing (NGS). All 2,059 patients were followed-up starting 1 year before their cancer diagnosis.

RESULTS

Frequency of NTRK gene fusion tumors was 3.1% (4/127) in pediatrics, 0.7% (8/1,151) for CRC, 0.3% (1/288) for NSCLC, 0.9% (1/114) for salivary gland cancer, and 0% (0/379) for sarcoma. Among pediatrics there was one case each of fibrosarcoma (TPM3::NTRK1), Ewing's sarcoma (LPPR1::NTRK2), primitive neuroectodermal tumor (DAB2IP::NTRK2), and papillary thyroid carcinoma (RAD51B::NTRK3). Among CRC patients, six harbored tumors with NTRK1 fusions (three fused with TPM3), one harbored a NTRK3::GABRG1 fusion, and the other a NTRK2::FXN/LPPR1 fusion. Microsatellite instability was higher in CRC patients with NTRK gene fusion tumors versus wild-type tumors (50.0% vs. 4.4%). Other detected fusions were SGCZ::NTRK3 (NSCLC) and ETV6::NTRK3 (salivary gland cancer). Four patients (three CRC, one NSCLC) received chemotherapy; one patient (with CRC) received radiotherapy.

CONCLUSION

NTRK gene fusions are rare in adult CRC, NSCLC, salivary tumors, sarcoma, and pediatric solid tumors.

A comparison of the histopathologic features of thyroid carcinomas with NTRK fusions to those with other malignant fusions

BACKGROUND

Chromosomal rearrangements involving one of the NTRK genes result in oncogenic driver mutations in thyroid carcinoma (TC) and serve as a target for therapy. We compared the clinicopathologic features of thyroid carcinomas with NTRK fusions vs. thyroid neoplasms with other malignancy associated gene fusions within our institution.

MATERIALS AND METHODS

Our pathology archives were searched from 2013 to 2023 for thyroid neoplasms with gene fusions, excluding THADA fusions and medullary thyroid carcinomas.

RESULTS

55 thyroid lesions were identified: 22 with NTRK fusions (NTRK cohort) and 33 with other fusions (non-NTRK cohort). On fine needle aspiration (FNA), 54% of the NTRK cohort were classified as Category V as per Bethesda System for Reporting Thyroid Cytology (TBSRTC) and 51.5% of non-NTRK cohort as TBSRTC Category III. In the NTRK cohort, the most common reported fusion was ETV6::NTRK3 and the most common reported fusion in the non-NTRK cohort was PAX8::PPAR-gamma. On histologic examination both cohorts were most commonly diagnosed as PTC follicular variant. Invasive features were more common in the NTRK cohort in comparison to the non-NTRK cohort. Locoregional recurrence occurred in 2/22 NTRK cases and 2/33 non-NTRK cases, with average time from surgery to recurrence being 5.5 months and 21 months, respectively. The majority of patients in both groups are alive with no evidence of disease.

CONCLUSIONS

Thyroid neoplasms with a malignancy associated gene fusion are likely to be diagnosed as subtype/variant of PTC. Patients whose thyroid lesions harbor NTRK fusions present with a PTC-FV that on presentation has more aggressive clinicopathologic findings and are likely to have earlier disease recurrence.

An Era of Advances in Systemic Therapies for Advanced Thyroid Cancer

Thyroid carcinomas comprise distinct pathologic subtypes. However, advancements in characterizing the molecular tumorigenesis of thyroid cancers have changed the treatment paradigm in the past decade. Genetic profiling has become an integral component of personalizing cancer care. Oral kinase inhibitors are currently standard-of-care therapies for progressive, radioactive iodine (RAI)-refractory differentiated thyroid carcinomas (DTCs) and medullary thyroid carcinomas (MTCs). Sorafenib, lenvatinib, and cabozantinib are multikinase inhibitors approved for patients with metastatic RAI-refractory DTC, whereas vandetanib and cabozantinib are approved for patients with MTC. Management of thyroid carcinomas has evolved such that targeted therapies have become therapeutic options for patients with BRAF, RET, NTRK, ALK, and ROS1 alterations and even have reported efficacy in anaplastic thyroid carcinomas. In this article, we review the advances made over the years in the treatment of metastatic thyroid carcinoma and focus on the systemic therapies that have recently transformed the treatment landscape of advanced disease.

[Thyroid carcinomas: the role of systemic therapies in internal medicine]

The molecular pathogenesis of thyroid carcinoma is well studied and of importance for the treatment of advanced stages. Differentiated, poorly differentiated and anaplastic carcinomas originate in the follicular cells, while medullary carcinomas derive from the C‑cells. The prognosis of differentiated thyroid carcinoma is generally very favourable after surgery and radioiodine therapy. Where tumours progress and lose the ability to enrich iodine, curative treatment is usually not possible. A strategy of watchful waiting is often appropriate. Activating mutations in BRAF or gene fusions of RET and NTRK provide opportunities for targeted therapies. These may be applied with the aim of restoring iodine uptake (redifferentiation). In the absence of molecular therapy targets, multityrosine kinase inhibitors (MKI) are the therapy of choice. If anaplastic thyroid carcinoma is suspected, rapid diagnostic workup including molecular pathology is warranted. Surgery where possible and radiochemotherapy are essential components of therapy. In the presence of a BRAF mutation, inhibition of BRAF and MEK is effective, even if it is not approved in Germany. Where molecular targets are lacking, combination therapy with the MKI lenvatinib and immune checkpoint inhibition is highly effective. Mutations in RET are present in the vast majority of cases of medullary thyroid carcinoma. In aggressive advanced disease, selective RET inhibition has recently been approved as first-line therapy and often leads to an objective response and long-lasting disease stabilisation. In summary, thyroid carcinomas are among the tumour entities for which molecularly targeted therapies can be used most frequently. The involvement of specialised centres is advisable.

Neoadjuvant Treatment of Locally Advanced Thyroid Cancer: A Preliminary Latin American Experience

Background: Surgical resection is not always achievable in thyroid cancer patients. Neoadjuvant therapy is rarely used, but recent trends favor multikinase inhibitors or selective tyrosine kinase inhibitors. These aim to reduce tumor volume, enabling previously unfeasible surgeries. Patients and Methods: Consecutive patients with locally advanced malignant thyroid tumors who received systemic therapies with a neoadjuvant intention were included in this retrospective multicenter case series conducted in five Latin American referral centers. Primary outcomes were pre- versus postneoadjuvant response evaluations using the Response Evaluation Criteria in Solid Tumors, feasibility of surgery, and completeness of resection. Secondary outcomes were mortality and status at the last visit. Results: Twenty-seven patients were included in this analysis. Patients with unresectable differentiated thyroid cancer (DTC) or poorly differentiated thyroid cancer (PDTC) received sorafenib (n = 6) or lenvatinib (n = 12), those with medullary thyroid cancer (MTC) were treated with vandetanib (n = 5) or selpercatinib (n = 1), and those with anaplastic thyroid cancer (ATC) harboring a BRAFV600E mutation (n = 3) received dabrafenib and trametinib. The median patient age was 66 years (range 12-82), and 52% of the patients were female. In patients with PTC and PDTC, the median reduction in the diameter of the primary tumor was 25% (range 0-100%) after a median of 6 months of treatment. Surgical intervention was performed in 10 (55%) of the patients. Among these, six patients (60%) achieved R0/R1 resection status. Six patients with MTC had a median reduction in tumor diameter of 24.5% (range 1-49) after a median treatment time of 9.5 months. Only one patient receiving selpercatinib, with a tumoral reduction of 25% could undergo surgery, resulting in an R2 resection due to extensive mediastinal extension. Three patients with ATC showed a median tumor diameter reduction of 42% (range 6.7-50) after a median treatment time of 2 months. Two patients underwent surgical intervention and achieved R1 and R2 resection, respectively. Conclusions: While neoadjuvant therapy achieved tumoral responses, surgical resection was feasible in 55% of DTC, 33% of ATC, and 16% of MTC patients, with R0/R1 resection in 26% of the cohort, underscoring the need for patient selection and further research in this area.

A study on the safety and efficacy of endoscopic thyroidectomy via axillary approach for the treatment of thyroid cancer

This study aims to evaluate the safety and efficacy of endoscopic thyroid cancer treatment using an axillary approach. Participants were allocated into 2 groups: one undergoing transaxillary endoscopic surgery and the other, traditional open surgery. We compared intraoperative and postoperative conditions, focusing on parameters such as intraoperative blood loss, duration of surgery, length of postoperative hospitalization, volume of postoperative drainage, number of lymph nodes cleared in the central region, neck pain scores, neck injury indices, cosmetic satisfaction, postoperative complications, and total hospitalization duration. Patients in the endoscopic treatment (ET) group experienced longer surgical times, less intraoperative bleeding, and increased postoperative drainage. These indicators showed significant differences between the groups (P < .05). For the group undergoing endoscopic surgery via the axillary approach, there was a lower neck pain score on the third postoperative day and higher cosmetic satisfaction at 3 months. However, there were no significant differences between the groups in terms of the number of lymph nodes cleared in the central area, and the incidence of complications such as difficulty breathing, difficulty swallowing, hoarseness, and subcutaneous hematoma (P > .05). The axillary approach endoscopic surgery group also showed significantly prolonged surgery times and postoperative hospital stays, with a significant increase in postoperative drainage fluid (P < .05). Concurrently, this technique involved smaller surgical incisions and effectively concealed scars in the armpit, leading to better outcomes in terms of intraoperative bleeding, neck pain scores, and postoperative cosmetic satisfaction. Non-inflatable ET via the axillary approach for treating thyroid cancer demonstrates promising efficacy and safety. It offers additional benefits of minimal pain and enhanced cosmetic outcomes, making it a viable option for clinical adoption and application.

Poorly differentiated thyroid carcinoma: molecular, clinico-pathological hallmarks and therapeutic perspectives

Poorly differentiated thyroid carcinoma (PDTC) is a rare and extremely aggressive tumor, accounting for about 2-15% of all thyroid cancer. PDTC has a distinct biological behavior compared to well-differentiated and anaplastic thyroid carcinoma and, in last years, it has been classified as a separate entity from both anatomopathological and clinical points of view. Nevertheless, there is still a lack of consensus among clinicians regarding inclusion criteria and definition of PDTC that affects its diagnosis and clinical management. Due to its rarity and difficulty in classification compared to other tumors, very few studies are available to date and series often include different histotypes in addition to PDTC. This review focuses on main studies concerning PDTC summarizing the evolution in the definition of its diagnosis criteria, clinicopathological features, management, and outcome. The data available confirm that the pathological evaluation and classification of PDTC are crucial and should therefore be standardized. Since the clinical presentation and prognosis of PDTC may vary widely depending on the different stage of the disease at diagnosis, the patient's management may differ in treatment and should be tailored to each patient. Finally, this review discusses advances in molecular insights of PDTC that, together with the implementation of both in vitro and in vivo models, will provide valuable insights into biological mechanisms of progression, metastasis, and invasion of this aggressive thyroid carcinoma. Further studies on larger, carefully selected series are needed to better assess the peculiar features of PDTC and to better define its management by focusing on the best diagnostic and therapeutic approaches.

Emerging therapeutic options for follicular-derived thyroid cancer in the era of immunotherapy

Although most follicular-derived thyroid cancers are well differentiated and have an overall excellent prognosis following treatment with surgery and radioiodine, management of advanced thyroid cancers, including iodine refractory disease and poorly differentiated/undifferentiated subtypes, is more challenging. Over the past decade, better understanding of the genetic drivers and immune milieu of advanced thyroid cancers has led to significant progress in the management of these patients. Numerous targeted kinase inhibitors are now approved by the U.S Food and Drug administration (FDA) for the treatment of advanced, radioiodine refractory differentiated thyroid cancers (DTC) as well as anaplastic thyroid cancer (ATC). Immunotherapy has also been thoroughly studied and has shown promise in selected cases. In this review, we summarize the progress in the understanding of the genetic landscape and the cellular and molecular basis of radioiodine refractory-DTC and ATC, as well as discuss the current treatment options and future therapeutic avenues.

Therapeutic benefit of larotrectinib over the historical standard of care in patients with locally advanced or metastatic infantile fibrosarcoma (EPI VITRAKVI study)

BACKGROUND

Patients with infantile fibrosarcoma (IFS) have shown strong and long-lasting responses to larotrectinib, a tropomyosin receptor kinase inhibitor (TRKi), in single-arm clinical trials. Conventional chemotherapy has also shown important efficacy. But, until now, no comparative data exist. This study aims to assess the therapeutic benefit of larotrectinib over the current standard of care (SOC) of chemotherapy in paediatric patients with locally advanced or metastatic IFS.

PATIENTS AND METHODS

EPI VITRAKVI is a retrospective, observational, externally controlled study (NCT05236257). Data of patients aged ≤21 years with locally advanced or metastatic IFS treated with larotrectinib in the phase I/II SCOUT trial (NCT02637687) were compared with those of an external historical control group (data of Institut Curie and Cooperative Weichteilsarkom Studiengruppe) treated with a chemotherapy-based regimen. Between-group differences were assessed after balancing groups using inverse probability of treatment weighting (IPTW).

RESULTS

In total, 93 patients were compared, 51 in the larotrectinib arm and 42 in the external control arm. After therapy, 4 patients (7.8%) in the larotrectinib group had a medical treatment failure event [start of new systemic treatment (2 cases), mutilating surgery (2 cases)] versus 15 (35.7%) in the external control group [start of new systemic treatment (6 cases), mutilating surgery (5 cases), radiation therapy (2 cases), and death (2 cases)]. Larotrectinib was associated with an 80% reduced likelihood of encountering a medical treatment failure event, when compared to the external control group (weighted and stratified hazard ratio 0.20, 95% confidence interval 0.06-0.63, P = 0.0060). These results were confirmed by sensitivity analyses, including exact matching, and subgroup analyses for number of lines of treatment.

CONCLUSIONS

Treatment with larotrectinib reduced the need of subsequent therapies compared to SOC with chemotherapy in children with locally advanced or metastatic IFS, regardless of the line of treatment.

State of the Art in 3D Culture Models Applied to Thyroid Cancer

Thyroid cancer (TC) is the prevalent endocrine tumor with a rising incidence, particularly in higher-income countries, leading to an increased interest in its management and treatment. While overall, survival rates for TC are usually favorable, advanced cases, especially with metastasis and specific histotypes, pose challenges with poorer outcomes, advocating the need of systemic treatments. Targeted therapies have shown efficacy in both preclinical models and clinical trials but face issues of resistance, since they usually induce partial and transient response. These resistance phenomena are currently only partially addressed by traditional preclinical models. This review explores the limitations of traditional preclinical models and emphasizes the potential of three-dimensional (3D) models, such as transwell assays, spheroids, organoids, and organ-on-chip technology in providing a more comprehensive understanding of TC pathogenesis and treatment responses. We reviewed their use in the TC field, highlighting how they can produce new interesting insights. Finally, the advent of organ-on-chip technology is currently revolutionizing preclinical research, offering dynamic, multi-cellular systems that replicate the complexity of human organs and cancer-host interactions.

[Personalized approach to anaplastic thyroid carcinoma]

BACKGROUND

Anaplastic thyroid carcinoma (ATC) represents the rarest but most aggressive tumor entity of the thyroid gland. In this respect, the treatment of advanced ATC has rapidly evolved in recent years. Recently, new personalized forms of treatment that address the somatic mutational status of the tumor have been increasingly used. The aim of this article is to provide an overview of current molecular-based and personalized treatment options for ATC.

METHODS

A current literature search was performed with a focus on personalized molecular-based treatment options for ATC.

RESULTS

The majority of patients suffering from ATC have an advanced tumor disease at the time of initial diagnosis. Despite multimodal treatment approaches consisting of surgery, external beam radiation therapy (EBRT) and chemotherapy (CTX), the prognosis of ATC is still poor. Accordingly, the focus of innovative treatment approaches is on molecular-based, individualized tumor therapy, including in particular BRAFV600E and multikinase inhibitors. The potential of the latter seems to lie particularly in combination therapy with immune checkpoint inhibitors. These treatment options can be used in both adjuvant and neoadjuvant settings. Neoadjuvant treatment of advanced ATC can achieve a potentially resectable treatment setting and improve the poor prognosis of affected patients; however, larger prospective and randomized studies on these combination therapies are currently pending.

CONCLUSION

The focus of future treatment approaches for ATC will be on individualized, molecular-based tumor therapy. In particular, the neoadjuvant use of these therapies may change the paradigm of ATC surgery as locally advanced as well as metastatic carcinomas can be converted to a potentially resectable status and made amenable to surgery.

Thyroid Cancer: A Review

Importance

Approximately 43 720 new cases of thyroid carcinoma are expected to be diagnosed in 2023 in the US. Five-year relative survival is approximately 98.5%. This review summarizes current evidence regarding pathophysiology, diagnosis, and management of early-stage and advanced thyroid cancer.

Observations

Papillary thyroid cancer accounts for approximately 84% of all thyroid cancers. Papillary, follicular (≈4%), and oncocytic (≈2%) forms arise from thyroid follicular cells and are termed well-differentiated thyroid cancer. Aggressive forms of follicular cell-derived thyroid cancer are poorly differentiated thyroid cancer (≈5%) and anaplastic thyroid cancer (≈1%). Medullary thyroid cancer (≈4%) arises from parafollicular C cells. Most cases of well-differentiated thyroid cancer are asymptomatic and detected during physical examination or incidentally found on diagnostic imaging studies. For microcarcinomas (≤1 cm), observation without surgical resection can be considered. For tumors larger than 1 cm with or without lymph node metastases, surgery with or without radioactive iodine is curative in most cases. Surgical resection is the preferred approach for patients with recurrent locoregional disease. For metastatic disease, surgical resection or stereotactic body irradiation is favored over systemic therapy (eg, lenvatinib, dabrafenib). Antiangiogenic multikinase inhibitors (eg, sorafenib, lenvatinib, cabozantinib) are approved for thyroid cancer that does not respond to radioactive iodine, with response rates 12% to 65%. Targeted therapies such as dabrafenib and selpercatinib are directed to genetic mutations (BRAF, RET, NTRK, MEK) that give rise to thyroid cancer and are used in patients with advanced thyroid carcinoma.

Conclusions

Approximately 44 000 new cases of thyroid cancer are diagnosed each year in the US, with a 5-year relative survival of 98.5%. Surgery is curative in most cases of well-differentiated thyroid cancer. Radioactive iodine treatment after surgery improves overall survival in patients at high risk of recurrence. Antiangiogenic multikinase inhibitors and targeted therapies to genetic mutations that give rise to thyroid cancer are increasingly used in the treatment of metastatic disease.

Neurotrophic-tyrosine receptor kinase gene fusion in papillary thyroid cancer: A clinicogenomic biobank and record linkage study from Finland

Selective tropomyosin receptor kinase (TRK) inhibitors are approved targeted therapies for patients with solid tumors harboring a neurotrophic tyrosine receptor kinase (NTRK) gene fusion. Country-specific estimates of NTRK gene fusion frequency, and knowledge on the characteristics of affected patients, are limited. We identified patients with histologically-confirmed papillary thyroid cancer (PTC) from Finland's Auria Biobank. TRK protein expression was determined by pan-TRK immunohistochemistry. Immuno-stained tumor samples were scored by a certified pathologist. Gene fusions and other co-occurring gene alterations were identified by next generation sequencing. Patient characteristics and vital status were determined from linked hospital electronic health records (EHRs). Patients were followed from 1 year before PTC diagnosis until death. 6/389 (1.5%) PTC patients had an NTRK gene fusion (all NTRK3); mean age 43.8 years (and none had comorbidities) at PTC diagnosis. Gene fusion partners were EML4 (n = 3), ETV6 (n = 2), and RBPMS (n = 1). Of 3/6 patients with complete EHRs, all received radioactive iodine ablation only and were alive at end of follow-up (median observation, 9.12 years). In conclusion, NTRK gene fusion is infrequent in patients with PTC. Linkage of biobank samples to EHRs is feasible in describing the characteristics and outcomes of patients with PTC and potentially other cancer types.

Challenging Case of Anaplastic Thyroid Cancer With Unusual Clinical and Histological Features: A Diagnostic Dilemma With Undifferentiated Pleomorphic Sarcoma

Thyroid cancer is a common malignancy worldwide, and its incidence is increasing rapidly, especially in women. In the majority of cases, it presents solely with a palpable neck swelling. Less commonly, the disease manifests with symptoms of advanced stages, such as superior vena cava (SVC) obstruction and indications of recurrent laryngeal nerve invasion. Anaplastic thyroid cancer is a rare variant of thyroid cancer and is considered to have one of the poorest prognoses, and its diagnosis and treatment are challenging. On the other hand, undifferentiated pleomorphic sarcoma is a differential diagnosis with many clinical and histological similarities, which can only be confirmed through immunohistochemical studies. We herein report a challenging case of a 69-year-old female patient who presented with obstructive symptoms, diagnosed with anaplastic thyroid cancer exhibiting unusual clinical and histological features.

Management of radioiodine refractory differentiated thyroid cancer: the Latin American perspective

Radioiodine (RAI) refractory differentiated thyroid cancer is an uncommon and challenging situation that requires a multidisciplinary approach to therapeutic strategies. The definition of RAI-refractoriness is usually a clear situation in specialized centers. However, the right moment for initiation of multikinase inhibitors (MKI), the time and availability for genomic testing, and the possibility of prescribing MKI and selective kinase inhibitors differ worldwide.Latin America (LA) refers to the territories of the world that stretch across two regions: North America (including Central America and the Caribbean) and South America, containing 8.5% of the world's population. In this manuscript, we critically review the current standard approach recommended for patients with RAI refractory differentiated thyroid cancer, emphasizing the challenges faced in LA. To achieve this objective, the Latin American Thyroid Society (LATS) convened a panel of experts from Brazil, Argentina, Chile, and Colombia. Access to MKI compounds continues to be a challenge in all LA countries. This is true not only for MKI but also for the new selective tyrosine kinase inhibitor, which will also require genomic testing, that is not widely available. Thus, as precision medicine advances, significant disparities will be made more evident, and despite efforts to improve coverage and reimbursement, molecular-based precision medicine remains inaccessible to most of the LA population. Efforts should be undertaken to alleviate the discrepancies between the current state-of-the-art care for RAI-refractory differentiated thyroid cancer and the present situation in Latin America.

Anaplastic thyroid cancer:Improved understanding of what remains a deadly disease

BACKGROUND

Anaplastic thyroid cancer (ATC) is a rare, undifferentiated form of thyroid cancer accounting for less that 2 % of thyroid cancers. Here we provide an overview of the contemporary understanding of ATC as well as discussing in detail any pertinent updates in the molecular understanding and treatment of this disease with reference to the 2021 American Thyroid Association (ATA) guidelines.

METHODS

A review of the literature regarding the understanding, management and prognosis of ATC was undertaken using both Pubmed and Cochrane databases along with local institutional experience. Studies published in the last 5 years were prioritised for inclusion.

RESULTS

Between 80 and 90 % of patients will have disease that has spread beyond the thyroid gland at presentation. Despite the use of aggressive, multimodal, conventional treatment strategies encompassing surgery and chemoradiotherapy, the median overall survival has remained between 3 and 6 months. Our understanding has evolved regarding the key oncogenic mutations involved in the development of ATC. These include BRAF, RAS, PI3K, PTEN, TP53 and TERT mutations. There is growing evidence that novel targeted therapies against these mutations may improve outcomes in this disease which has led to FDA approval of dabrafenib/trametinib combined BRAF/Mek inhibition.

CONCLUSIONS

The prognosis of ATC remains dismal. Recent development and approval of targeted therapies offers hope of improved oncologic outcomes with further data eagerly awaited surrounding the impact of these targeted therapies.