Safety and antitumor activity of the anti-PD-1 antibody pembrolizumab in patients with advanced, PD-L1-positive papillary or follicular thyroid cancer

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".

Inflammation and Thyroid Cancer: Deciphering the Role of Blood Immune Indexes

BACKGROUND

Inflammation within tumor microenvironments has been correlated to numerous malignancies. This study aims to explore its significance in thyroid cancer (TC).

METHODS

Retrospective analysis of 157 thyroid carcinomas and 40 benign cases involved initial univariate analysis. The value of neutrophils/value of lymphocytes (NLR), value of platelets/value of lymphocytes (PLR), value of lymphocytes/value of monocytes (LMR), and value of platelets × value of neutrophils/value of lymphocytes (SII) indexes were related to TC characteristics and number and location of involved lymph nodes using χ2 or Fischer's exact tests for categorical variables and Student's t-tests for continuous ones. A 1:1 propensity score matching balanced malignant and benign TC groups based on age, sex, and tumor size was used. Post-matching, a multivariate logistic model integrated sex, age, Central lymph node metastases (CLNM), and SII index. Statistically significant immune index values underwent ROC curve analysis for determining cut-offs. Among the 157 malignant TC, median test and density plots were performed.

RESULTS

The SII index emerged as a predictor of malignancy in both univariate and multivariate analyses (p-value = 0.0202). The ROC curve indicated a cut-off SII value of 465.71, (specificity = 58% [95% CI: 0.43-0.73]; sensitivity = 80% [95% CI: 0.68-0.93]). Median SII index values for tumor sizes of 1 and >1 were 522.8 and 654.8, respectively (p-value = 0.016). When central lymph nodes metastases(CLNMs) was considered (CLNM = 0 vs. CLNM > 0), median SII values were 530.7 and 1121.7, respectively (p-value = 0.011).

CONCLUSIONS

The SII index appears to be a valuable tool in the presence of TC, showing correlations with malignancy, tumor size, and CLNMs.

The Revolution of Targeted Therapies in Thyroid Cancer Treatment: Present and Future Promising Anti-Cancer Drugs

Thyroid cancer prevalence has increased in the last few decades. Whereas the majority of well-differentiated histotypes have effective therapeutic options, the most advanced cases lacked successful treatment until recent years. Genomic alterations have emerged as targets for new anti-cancer drugs. This molecular knowledge is gradually being translated into sophisticated approaches for the stratification, management, and therapies of patients with thyroid carcinomas. The genomic characterisation of tumours in clinical assistance serves as a tool for enhancing the prognostic assessment of patients with thyroid cancer and predicting their responses to the agents. The MAPK pathway is the most predominantly activated molecular route in this cancer. Several drugs have been developed to inhibit this pathway at different levels. However, the acquired resistance that emerges is the main problem in their use. Other strategies targeting not only driver mutations but also those that confer aggressive behaviour on tumours can be potential targetable options. Due to the new therapies, patients with the most aggressive histotypes have improved survival rates. Adverse events, although manageable, have a high prevalence among the current therapies. Selective inhibitors, immunotherapies, and the combination of both will play a pivotal role in the treatment and the improvements in overall survival in thyroid cancer patients.

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.

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.

Wnt/B-catenin Activation and TP53 Mutations Associate With Distinct Immune Profiles in Advanced Thyroid Cancer

CONTEXT

Anaplastic thyroid carcinomas (ATCs) and poorly differentiated thyroid carcinomas (PDTCs) exhibit distinct immune-related gene expression profiles. Most ATCs are characterized by active immune interactions (hot or altered immunosuppressed immunophenotypes), while PDTCs are largely immunologically inert (cold immunophenotypes).

OBJECTIVE

This study aimed to elucidate the mechanisms driving these divergent immunological fates, focusing on the Wnt/β-catenin pathway and TP53 mutations.

RESULTS

Our data reveal that ATCs frequently harbor TP53 mutations (83.3%), which correlate with a hot immunophenotype, characterized by high expression of β-catenin-regulated cytokine CCL4 and recruitment of CD103 + dendritic cells. Conversely, PDTCs, with a lower incidence of TP53 mutations (12.5%), often exhibit a cold immunophenotype. In cold cancers and PDTCs, β-catenin is overexpressed, suggesting that Wnt/β-catenin pathway activation drives immune exclusion through CCL4 downregulation.Further analysis indicated that loss of p53 function is inversely correlated with β-catenin expression. P53-mutated cancers showed significantly higher expression of CCL4 and densities of CD103 + dendritic cells compared to their p53-wild-type counterparts. Additionally, p53-mutated ATCs expressed a higher number of immune-related genes, supporting the role of p53 loss in activating immune responses in cancer.

CONCLUSION

Our study indicates a potential correlation between the activation of the Wnt/β-catenin pathway and the development of cold thyroid cancers, which may be mediated by the suppression of CCL4 expression. Concurrently, mutations in the p53 gene appear to be linked with the occurrence of hot thyroid cancers. While these associations are compelling, they are based on observational data. Experimental research is necessary to determine the causal relationships underlying these findings.

Cabozantinib Plus Ipilimumab/Nivolumab in Patients With Previously Treated Advanced Differentiated Thyroid Cancer

BACKGROUND

This investigator-initiated phase II trial aimed to evaluate the efficacy of cabozantinib in combination with nivolumab and ipilimumab (CaboNivoIpi) in previously treated patients with radioactive iodine-refractory differentiated thyroid cancer.

METHODS

Eligible patients with radioactive iodine-refractory differentiated thyroid cancer who progressed on 1 prior line of vascular endothelial growth factor receptor-targeted therapy received a 2-week run-in of cabozantinib monotherapy followed by CaboNivoIpi for 4 cycles (cycle length = 6 weeks), followed by cabozantinib plus nivolumab (cycle length = 4 weeks) until disease progression. The primary endpoint was objective response rate (ORR) within the first 6 months of treatment. A Simon optimal 2-stage design allowed for an interim analysis after accrual of 10 evaluable patients. At least 5 responses were needed to proceed to stage 2.

RESULTS

Among 11 patients enrolled, the median age was 69 years. Prior vascular endothelial growth factor receptor-targeted therapies included lenvatinib, pazopanib, and sorafenib plus everolimus. Median follow-up was 7.9 months. Among 10 evaluable patients, ORR within the first 6 months of treatment was 10% (1 partial response). Median progression-free survival was 9 months (95% CI, 3.0-not reached) and median overall survival was 19.2 months (95% CI, 4.6-not reached). Grade 3/4 treatment-related adverse events (AEs) were noted in 55% (6/11) and grade 5 AEs in 18% (2/11) of patients. The most common treatment-related AE was hypertension. The study did not reach its prespecified efficacy threshold.

CONCLUSION

CaboNivoIpi had low ORRs and a high rate of grade ≥3 treatment-related AEs.

CLINICAL TRIAL REGISTRATION

NCT03914300.

Research trends and hotspots of radioiodine-refractory thyroid cancer treatment in the twenty-first century: a bibliometric analysis

The treatment of radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) has made significant advancements in the twenty-first century. This study aimed to assess the current state of research and identify potential new directions by conducting a bibliometric analysis of scientific publications on RAIR-DTC treatment. Publications relevant to RAIR-DTC, published from January 1, 2000, to December 31, 2023, were retrieved from the Web of Science Core Collection. Bibliometric analyses of major keywords, authors, countries, institutions, publications, and journals were conducted using CiteSpace and VOSviewer. A total of 859 papers were included in the analysis. The results demonstrated a rising trend in the number of publications over time. The United States was identified as the leading contributor in terms of publication output, citations, and international collaborations. Gustave Roussy emerged as the top organization in publication productivity, while the journal Thyroid had the highest number of related publications. The research on RAIR treatment was categorized into three key hotspots: clinical trials of targeted therapies, novel therapeutic strategies, and debates surrounding the RAIR-DTC management. RAIR-DTC research is expanding from the clinical trial phase of tyrosine kinase inhibitor monotherapy to a more complex combination therapy strategy, in particular, the synergistic effect of immune checkpoint inhibitors and other therapeutic agents, requiring more high-quality prospective studies to validate the clinical benefits. Moreover, the timely identification of RAIR-DTC patients holds the potential to enable early disease intervention, constituting a pivotal novel research direction in the future.

Emerging insights into thyroid cancer from immunotherapy perspective: A bibliometric analysis

Thyroid cancer is a common endocrine malignancy that poses considerable therapeutic challenges in treating anaplastic carcinoma and advanced aggressive disease. Immunotherapy has become a prominent strategy for cancer treatment, and has shown remarkable advancements in recent years. In this study, we utilized visualization and bibliometric tools to analyze publications on thyroid cancer immunotherapy from the Web of Science Core Collection (WoSCC). A total of 409 articles were included, with an annual increase in both publications and citations since 2016. China leads research efforts in this area, while the University of Texas System and UTMD Anderson Cancer Center rank first in publication output. The journal Thyroid has garnered the highest citations. Notable authors contributing to this field include Antonelli Alessandro, Fallahi Poupak, and Wang Yu. Current research hotspots include immune checkpoint inhibitors, combination therapies involving immunotherapy with targeted therapy, CAR-T cell therapy, and modulation of the tumor microenvironment, all of which underscore the evolving landscape and potential for innovative treatments in thyroid cancer.

State of Knowledge About Thyroid Cancers in the Era of COVID-19-A Narrative Review

Thyroid cancer (TC), due to its heterogeneous nature, remains a clinical challenge. Many factors can initiate the carcinogenesis process of various types of TC, which complicates diagnosis and treatment. The presented review gathers current information on specific types of TC, taking into account the effects of the COVID-19 pandemic. It is likely that COVID-19 has influenced and continues to influence the function of the thyroid gland. A high percentage of patients with COVID-19 showing simultaneous pathological changes in the thyroid suggests that SARS-CoV-2 may disrupt the function of this gland and initiate pro-oxidative mechanisms, inflammatory states, and autoimmune diseases, thereby promoting the formation of neoplastic changes. Furthermore, changes in the expression of the ACE2, TMPRSS2, CLEC4M and DPP4 genes, observed in TC, also occur in COVID-19. Therefore, it is probable that the interaction of SARS-CoV-2 with thyroid cell receptors may initiate carcinogenesis in this gland. Additionally, some drugs used in TC therapy (e.g., levothyroxine) may increase the affinity of SARS-CoV-2 for cells, which could contribute to a more severe course of COVID-19 and the emergence of long-term symptoms (post-COVID-19). Moreover, the consequences of sanitary restrictions (limited access to medical services, reduction in endocrinological and oncological procedures) that took place in many countries during the COVID-19 pandemic may lead in the future to an increased number of missed diagnoses and the emergence of aggressive cancers.

Dual Immune Checkpoint Inhibition in Patients With Aggressive Thyroid Carcinoma: A Phase 2 Nonrandomized Clinical Trial

Importance

Aggressive thyroid carcinoma, including radioiodine refractory (RAIR) differentiated thyroid carcinoma (DTC), medullary thyroid carcinoma (MTC), and anaplastic thyroid carcinoma (ATC), are associated with significant morbidity and mortality and have limited therapeutic options. Distinct immune profiles have been identified in thyroid cancer subtypes suggesting they may be susceptible to immune checkpoint inhibition.

Objective

To evaluate the efficacy of anti-programmed cell death 1 nivolumab and anti-cytotoxic lymphocyte-associated protein 4 ipilimumab in patients with aggressive thyroid carcinoma.

Design, Setting, and Participants

This phase 2 nonrandomized clinical trial enrolled patients with RAIR DTC in a single center from October 2017 to May 2019, with exploratory cohorts in MTC and ATC. The data were analyzed between June 2021 and September 2023.

Intervention

Intravenous nivolumab, 3 mg/kg, every 2 weeks and ipilimumab, 1 mg/kg, every 6 weeks until disease progression, intolerable adverse events, or a maximum duration of 2 years.

Main Outcomes and Measures

The primary end point of the study was objective response rate (ORR) in RAIR DTC, which was scored according to RECIST (Response Evaluation Criteria in Solid Tumours), version 1.1. Key secondary end points included safety, progression-free survival, overall survival, and biomarker analyses.

Results

A total of 51 patients were registered, and 49 patients were evaluable for analysis. The median (range) age was 65 years (30-88 years), and 25 participants (51%) were female. ORR in the DTC cohort was 9.4% (3/32 [95% CI, 2.8%-28.5%]), with all partial responses in either oncocytic carcinoma (2/6 [33.0%]) or poorly differentiated thyroid carcinoma (1/5 [20.0%]). Clinical benefit rates were 62.5% (20/32) in the overall DTC cohort, including 83.3% (5/6) in oncocytic carcinoma and 40% (2/5) in poorly differentiated thyroid carcinoma. ORR in the exploratory ATC cohort was 30.0% (3/10 [95% CI, 6.7%-65.2%]), with a clinical benefit rates of 50.0% (5/10). No responses were observed in the exploratory MTC cohort. The safety profile was similar to prior reports with dual immune checkpoint inhibition (pruritus, rash, diarrhea, fatigue, and elevation of lipase and liver enzymes). The presence of NRAS tumor genetic sequence variations, but not BRAF V600E, was associated with worse outcomes.

Conclusions and Relevance

This phase 2 nonrandomized clinical trial reported clinical activity of dual immune checkpoint inhibition in aggressive thyroid cancer. The study did not meet its end point in the primary population of RAIR DTC and does not support further investigation in non-biomarker-selected DTC. However, the signal observed in ATC may merit further evaluation.

Trial Registration

ClinicalTrials.gov Identifier: NCT03246958.

Consensus Statement: Recommendations on Actionable Biomarker Testing for Thyroid Cancer Management

Thyroid cancer management is rapidly changing. The identification of actionable biomarkers through both germline and somatic testing are now an integral part of directing patient management. However, deficiencies and disparities within existing thyroid cancer biomarker test approaches are resulting in inconsistent application for patient care. An expert panel was convened to create consensus biomarker testing algorithms and recommendations on actionable biomarker testing for patients diagnosed with medullary thyroid cancer, non-anaplastic follicular cell-derived thyroid cancer, or anaplastic follicular cell-derived thyroid cancer who may benefit from targeted therapies. A review of international guidelines was performed to determine the current state, and a literature review was carried out to further evaluate the evidence supporting the use of actionable biomarkers in patients diagnosed with thyroid cancer. Thyroid biomarker-related gaps impacting patient care were also discussed, with an emphasis on the importance of a multidisciplinary team approach for optimal patient care. The recommendations are presented with the aim to help physicians navigate the current thyroid cancer biomarker testing landscape with its many challenges, balancing aspirational care with what is practical and feasible in terms of economic realities and jurisdictional constraints. By remaining therapy-agnostic, these algorithms and recommendations are broadly applicable.

Pathogenesis and Management Strategies in Radioiodine-Refractory Differentiated Thyroid Cancer: From Molecular Mechanisms Toward Therapeutic Approaches: A Comprehensive Review

Thyroid cancer (TC) remains the most common cancer in endocrinology. Differentiated thyroid cancer (DTC), the most common type of TC, generally has a favorable outlook with conventional treatment, which typically includes surgery along with radioiodine (RAI) therapy and thyroid-stimulating hormone (TSH) suppression through thyroid hormone therapy. However, a small subset of patients (less than 5%) develop resistance to RAI. This resistance occurs due to the loss of Na/I symporter (NIS) activity, which is crucial for iodine absorption in thyroid cells. The decline in NIS activity appears to be due to gene modifications, reconfigurations with irregular stimulation of signaling pathways such as MAPK and PI3K/Akt pathways. These molecular changes lead to a diminished ability of DTC cells to concentrate iodine, which makes RAI therapy ineffective. As a consequence, patients with radioiodine-refractory DTC require alternative treatments. Therapy with tyrosine kinase inhibitors (TKIs) has emerged as the primary treatment option to inhibit proliferation and growth of RAIR-DTC, targeting the pathways responsible for tumor progression. In this article, we analyze molecular processes responsible for RAI resistance and explore both conventional and emerging therapeutic strategies for managing RAIR-DTC, aiming to improve patient outcomes.

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.

Impact of Hashimoto's thyroiditis on the tumor microenvironment in papillary thyroid cancer: insights from single-cell analysis

This study investigates the impact of Hashimoto's thyroiditis (HT), an autoimmune disorder, on the papillary thyroid cancer (PTC) microenvironment using a dataset of 140,456 cells from 11 patients. By comparing PTC cases with and without HT, we identify HT-specific cell populations (HASCs) and their role in creating a TSH-suppressive environment via mTE3, nTE0, and nTE2 thyroid cells. These cells facilitate intricate immune-stromal communication through the MIF-(CD74+CXCR4) axis, emphasizing immune regulation in the TSH context. In the realm of personalized medicine, our HASC-focused analysis within the TCGA-THCA dataset validates the utility of HASC profiling for guiding tailored therapies. Moreover, we introduce a novel, objective method to determine K-means clustering coefficients in copy number variation inference from bulk RNA-seq data, mitigating the arbitrariness in conventional coefficient selection. Collectively, our research presents a detailed single-cell atlas illustrating HT-PTC interactions, deepening our understanding of HT's modulatory effects on PTC microenvironments. It contributes to our understanding of autoimmunity-carcinogenesis dynamics and charts a course for discovering new therapeutic targets in PTC, advancing cancer genomics and immunotherapy research.

Combination Targeted Therapy with Pembrolizumab and Lenvatinib in Progressive, Radioiodine-Refractory Differentiated Thyroid Cancers

PURPOSE

Lenvatinib, a potent multikinase inhibitor, improves progression-free survival (PFS) in patients with radioiodine (RAI)-refractory differentiated thyroid cancer; however, most patients experience disease progression, warranting further therapy. We evaluated the efficacy and safety of lenvatinib plus pembrolizumab in these patients.

PATIENTS AND METHODS

We enrolled patients with progressive, RAI-refractory differentiated thyroid cancer who were either naïve to multikinase inhibitors (cohort 1) or who had progressed on lenvatinib (cohort 2). Patients received oral lenvatinib daily (cohort 1, 20 mg; cohort 2, dose at progression) and intravenous pembrolizumab (200 mg) every 21 days.

RESULTS

In cohorts 1 and 2, 30 and 27 patients were enrolled, respectively. Adverse events were consistent with those observed in other cancers. In cohort 1, the confirmed overall response rate was 65.5%. There were no complete responses (primary endpoint). The 12- and 18-month PFS were 72.0% and 58.0%, respectively, and the median PFS was 26.8 months. In cohort 2, the confirmed overall response rate was 16% (primary endpoint), and the median PFS was 10.0 months (95% confidence interval, 7.0-17.9 months). Tumor histology, driver mutations, and immune-related biomarkers, including PD-L1 expression, thyroid-specific antibody levels, and CD8+ T-cell tumor infiltrate, did not correlate with response to therapy. Increased baseline peripheral blood monocytes and neutrophil to lymphocyte ratio were associated with a worse PFS in cohort 1.

CONCLUSIONS

Lenvatinib plus pembrolizumab may enhance the durability of lenvatinib monotherapy in lenvatinib-naïve patients. Furthermore, the addition of pembrolizumab may be a viable salvage therapy for patients who have progressed on lenvatinib.

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.

A comprehensive pan-cancer analysis revealing SPAG6 as a novel diagnostic, prognostic and immunological biomarker in tumor

Background

There have been studies on the role of sperm-associated antigen 6 (SPAG6) in cytoskeleton formation and growth cone stability, but it is also unknown how spag6 affect tumor growth and development. The aim of this study was to clarify the role of SPAG6 in pan-cancer, with some findings about thyroid carcinoma (THCA) validated through experiments.

Methods

We examined the role of SPAG6 in pan-cancer, with the data being collected from databases. Further analysis was conducted to assess its correlations with prognosis, gene heterogeneity, stemness, and tumor immunity. The interacting proteins of SPAG6 were also identified, and gene ontology enrichment analysis was performed to determine its biological function. We preliminarily confirmed the role of SPAG6 via in vitro experiments and immunofluorescence staining.

Results

This study found that SPAG6 expression was differentially expressed in cancers and at various tumor stages and grades. In stomach and esophageal carcinoma (STES), stomach adenocarcinoma (STAD), kidney renal clear cell carcinoma (KIRC), lung squamous cell carcinoma (LUSC), and adrenocortical carcinoma (ACC), SPAG6 expression was correlated with gender. SPAG6 expression was also found to be correlated with prognostic value, with low expression being associated with poor prognosis. Furthermore, SPAG6 expression was positively linked with immune-related cells in HNSC, chemokine receptors in LUSC, and immune checkpoint genes in THCA. Furthermore, SPAG6 overexpression suppressed the malignant phenotypes of THCA cells, manifested by slower proliferation and decreased migration. The different SPAG6 expression in THCA led to different malignant phenotypes, which are involved in the upregulation of DNA repair, MYC targets, peroxisome, and G2M checkpoint.

Conclusions

SPAG6 plays a significant role as an oncogene and can be used as a marker to predict the prognosis of cancer. SPAG6 influences both the tumor immune infiltration and microenvironment, making it a promising immunotherapeutic target for tumor therapy.

B7-H3 and ICAM-1 are potentially therapeutic targets for thyroid carcinoma

Although most differentiated thyroid carcinoma has a clinically favorable prognosis, some of specific types of thyroid cancer (such as anaplastic thyroid carcinoma and advanced papillary thyroid carcinoma) show fatal outcomes and require novel treatments. Immunotherapy is a promising avenue for the treatment of advanced thyroid carcinoma. B7-H3 (B7 homolog 3 protein) and ICAM-1 (intercellular adhesion molecule 1), as two important immune checkpoints (ICPs), is becoming hopeful target spots for immunotherapy. A growing amount of evidence has suggested that B7-H3 and ICAM-1 are upregulated in papillary thyroid carcinoma. However, their expression level in specific types of thyroid cancer remains largely unclear. In the present study, we explored the expression level of B7-H3 and ICAM-1 in different types of thyroid carcinoma. In the groups of the TCGA cohort, both B7-H3 and ICAM-1 mRNA were highly expressed in thyroid carcinoma. Furthermore, the patients with Stage2, 61-80y, Follicular thyroid papillary carcinoma and N0 had lower B7-H3 and ICAM-1 mRNA expression. In the groups of our cohort, PTCs and ATCs showed frequently moderate to strong expression of B7-H3 and ICAM-1 protein expression. The significant relevance of B7-H3 staining score with ICAM-1 staining score was observed in TCGA database and our cohort, which might open avenues for the combination therapy in advanced thyroid cancer.

Projecting long-term clinical outcomes with larotrectinib compared with immune checkpoint inhibitors in metastatic nonsmall cell lung cancer and differentiated thyroid cancer

BACKGROUND

Larotrectinib is approved for patients with advanced NTRK gene fusion-positive solid tumors. Prior studies demonstrated promising results with larotrectinib compared with other systemic therapy. However, comparisons to checkpoint inhibitors, such as nivolumab or pembrolizumab, have not been done.

OBJECTIVE

To estimate and compare expected life-years (LYs) and quality-adjusted LYs (QALYs) for patients with nonsmall cell lung cancer (NSCLC) eligible for larotrectinib vs patients with unknown NTRK gene fusion status on nivolumab or pembrolizumab. We also assessed patients with metastatic differentiated thyroid cancer (DTC), as pembrolizumab may be considered in certain circumstances.

METHODS

We developed partitioned survival models to project long-term comparative effectiveness of larotrectinib vs nivolumab or pembrolizumab. Larotrectinib survival data were derived from an updated July 2021 analysis of 21 adult patients (≥18 years of age) with metastatic NTRK gene fusion-positive NSCLC and 21 with DTC. Survival inputs for nivolumab and pembrolizumab were obtained from published articles. Progression-free and overall survival were estimated using survival distributions (Exponential, Weibull, Log-logistic, and Log-normal). Exponential fits were chosen based on goodness-of-fit and clinical plausibility.

RESULTS

In NSCLC, larotrectinib resulted in gains of 5.87 and 5.91 LYs compared to nivolumab and pembrolizumab, respectively, which translated to gains of 3.53 and 3.56 QALYs. In DTC, larotrectinib resulted in a gain of 5.23 LYs and 4.24 QALYs compared to pembrolizumab.

CONCLUSIONS

In metastatic NSCLC and DTC, larotrectinib may produce substantial life expectancy and QALY gains compared to immune checkpoint inhibitors. Additional data with longer follow-up will further inform this comparison.

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.

Palliative treatment of generalized metastatic follicular carcinoma of thyroid after operation: A case report and literature review

RATIONALE

Follicular carcinoma of thyroid is a rare pathological type of thyroid carcinoma, accounting for 4.5% of the total. At present, the main treatment methods include surgery, iodine therapy, thyroid hormone inhibitors, etc. Targeted drug therapy is very important for distant metastasis and iodine-refractory differentiated thyroid cancer.

PATIENT CONCERNS

This clinical case is a 51-year-old male patient with follicular carcinoma of thyroid.

DIAGNOSES

After 7 years of total thyroidectomy, multiple distant metastasis occurred to bilateral lungs, bones, multiple lymph nodes, etc.

INTERVENTION

After multidisciplinary consultation in the department of oncology, thoracic surgery, nuclear medicine and other departments, he received targeted drug therapy of Lenvatinib.

OUTCOMES

After 3 months, his condition was partially relieved, and his quality of life was significantly improved. After 11 months of treatment, the evaluated efficacy was still in remission.

LESSON

Late metastatic thyroid cancer is faced with dilemma of radioiodine refractory after traditional treatment. This will provide further evidence for therapeutic intervention in similar patients in the future.

Novel T cell exhaustion gene signature to predict prognosis and immunotherapy response in thyroid carcinoma from integrated RNA-sequencing analysis

Exhausted CD8+ T lymphocytes and tumor-associated macrophages play critical roles in determining cancer prognosis and the efficacy of immunotherapy. Our study revealed a negative correlation between exhausted CD8+ T lymphocytes and prognosis in thyroid carcinoma (THCA). Consensus clustering divided patients into two subgroups of exhaustion with different prognoses, as defined by marker genes of exhausted CD8+ T cells. Subsequently, we constructed an eight-gene prognostic signature, and developed a risk score named the exhaustion-related gene score (ERGS) to forecast both prognosis and immunotherapy response in THCA. Bulk RNA sequencing analysis revealed a higher prevalence of M2 macrophages, indicative of an immunosuppressive tumor microenvironment (TME), in the high-ERGS group. Single-cell RNA sequencing showed that SPP1+ macrophages and CD14+ monocytes infiltrations were positively associated with higher ERGS. Functionally, it was determined that SPP1+ macrophages exert an immunosuppressive role, while CD14+ monocytes were implicated in promoting tumor progression and angiogenesis. Analysis of cell-cell interactions between SPP1+ macrophages and T cells highlighted the activation of the SPP1-CD44 and MIF-CD74 axes, both of which could foster an immunosuppressive TME. Therapeutic strategies that target SPP1+ macrophages, CD14+ monocytes, and the SPP1-CD44 and MIF-CD74 axes may potentially improve the prognosis and amplify the immunotherapy response in THCA patients.

Summary and update on the management of differentiated thyroid cancer in 2023

The 6-fold increase in the incidence of differentiated thyroid cancer over the past 30 years in industrialized countries can be mainly attributed to improved detection. At the same time, in addition to the excellent prognosis for low-risk cancers, improved survival in metastatic forms has been also reported, likely due to the progress made recently in the treatment of aggressive forms, for which there is now an extensive therapeutic arsenal. Today, clinical management of differentiated thyroid cancer represents a paradigm of precision oncology, with personalized, risk-adapted therapeutic strategies. This has led to therapeutic de-escalation in those forms with a good prognosis, while targeted treatments play an increasingly important role in the management of radioiodine-refractory or advanced cancers. While endocrinologists will not always have the opportunity to prescribe these treatments, they will be called on to support and monitor patients during treatment. The aim of this article is to provide an overview of treatment options for differentiated thyroid cancer in 2023.

Comparative efficiency of differential diagnostic methods for the identification of BRAF V600E gene mutation in papillary thyroid cancer (Review)

V-Raf murine sarcoma viral oncogene homolog B1 (BRAF) encodes a serine-threonine kinase. The V600E point mutation in the BRAF gene is the most common mutation, predominantly occurring in melanoma, and colorectal, thyroid and non-small cell lung cancer. Particularly in the context of thyroid cancer research, it is routinely employed as a molecular biomarker to assist in diagnosing and predicting the prognosis of papillary thyroid cancer (PTC), and to formulate targeted therapeutic strategies. Currently, several methods are utilized in clinical settings to detect BRAF V600E mutations in patients with PTC. However, the sensitivity and specificity of various detection techniques vary significantly, resulting in diverse detection outcomes. The present review highlights the advantages and disadvantages of the methods currently employed in medical practice, with the aim of guiding clinicians and researchers in selecting the most suitable detection approach for its high sensitivity, reproducibility and potential to develop targeted therapeutic regimens for patients with BRAF gene mutation-associated PTC.

Chronic Lymphocytic Thyroiditis with Oncocytic Metaplasia Influences PD-L1 Expression in Papillary Thyroid Carcinoma

BACKGROUND

Despite the increasing recognition of PD-L1 as predictor of immunotherapeutic response in various malignancies, its role and prognostic significance in thyroid cancer remain underexplored and subject to debate. This study begins to address this gap by comprehensively analyzing PD-L1 expression in papillary thyroid carcinoma (PTC) and investigating its correlation with key clinicopathological variables.

METHODS

We conducted immunohistochemistry (IHC) to assess PD-L1 expression in whole-tissue sections from 121 primary papillary thyroid carcinoma (PTC) cases. We then analyzed the correlations between PD-L1 expression and various clinicopathological variables.

RESULTS

PD-L1 expression was detected in 33.1% of papillary thyroid carcinomas (PTCs), predominantly exhibiting weak to moderate intensity. Notably, this study found no significant correlation between PD-L1 expression and various clinicopathological variables. The lack of association with traditional factors such as age, sex, histological subtype, and tumor size suggests the complex and multifaceted nature of PD-L1 regulation in PTC. Multivariate logistic regression analysis identified chronic lymphocytic thyroiditis with oncocytic metaplasia as the sole independent predictor of PD-L1 expression (P = 0.014), underlining the potential influence of the tumor microenvironment on immune checkpoint expression in PTC.

CONCLUSIONS

Our study underscores the intricate interplay between chronic lymphocytic thyroiditis with oncocytic metaplasia and PD-L1 expression in papillary thyroid carcinoma. The observed link suggests a potential avenue for therapeutic intervention using anti-PD-1/PD-L1 therapies in surgery-refractory PTC. Understanding the dynamics of immune checkpoint regulation in the context of the tumor microenvironment is crucial for devising effective treatment strategies. Future research endeavors should delve deeper into the molecular mechanisms underlying this interaction and explore its implications for patient outcomes. As the field of immunotherapy continues to evolve, our findings contribute valuable insights into the complex immunological landscape of thyroid cancer.

A distinct tumor microenvironment makes anaplastic thyroid cancer more lethal but immunotherapy sensitive than papillary thyroid cancer

Both anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) originate from thyroid follicular epithelial cells, but ATC has a significantly worse prognosis and shows resistance to conventional therapies. However, clinical trials found that immunotherapy works better in ATC than late-stage PTC. Here, we used single-cell RNA sequencing (scRNA-Seq) to generate a single-cell atlas of thyroid cancer. Differences in ATC and PTC tumor microenvironment components (including malignant cells, stromal cells, and immune cells) leading to the polarized prognoses were identified. Intriguingly, we found that CXCL13+ T lymphocytes were enriched in ATC samples and might promote the development of early tertiary lymphoid structure (TLS). Last, murine experiments and scRNA-Seq analysis of a treated patient's tumor demonstrated that famitinib plus anti-PD-1 antibody could advance TLS in thyroid cancer. We displayed the cellular landscape of ATC and PTC, finding that CXCL13+ T cells and early TLS might make ATC more sensitive to immunotherapy.

Checkpoint Inhibition in Addition to Dabrafenib/Trametinib for BRAFV600E-Mutated Anaplastic Thyroid Carcinoma

Background: The dabrafenib plus trametinib combination (DT) has revolutionized the treatment of BRAFV600E-mutated anaplastic thyroid carcinoma (BRAFm-ATC). However, patients eventually develop resistance and progress. Single-agent anti-PD-1 inhibitor spartalizumab has shown a median overall survival (mOS) of 5.9 months. Combination of immunotherapy with BRAF/MEK inhibitors (BRAF/MEKi) seems to improve outcomes compared with BRAF/MEKi alone, although no direct comparison is available. BRAF-targeted therapy before surgery (neoadjuvant approach) has also shown improvement in survival. We studied the efficacy and safety of DT plus pembrolizumab (DTP) compared with current standard-of-care DT alone as an initial treatment, as well as in the neoadjuvant setting. Methods: Retrospective single-center study of patients with BRAFm-ATC treated with first-line BRAF-directed therapy between January 2014 and March 2023. Three groups were evaluated: DT, DTP (pembrolizumab added upfront or at progression), and neoadjuvant (DT before surgery, and pembrolizumab added before or after surgery). The primary endpoint was mOS between DT and DTP. Secondary endpoints included median progression-free survival (mPFS) and response rate with DT versus DTP as initial treatments, and the exploratory endpoint was mOS in the neoadjuvant group. Results: Seventy-one patients were included in the primary analysis: n = 23 in DT and n = 48 in DTP. Baseline demographics were similar between groups, including the presence of metastatic disease at start of treatment (p = 0.427) and prior treatments with surgery (p = 0.864) and radiation (p = 0.678). mOS was significantly longer with DTP (17.0 months [confidence interval CI, 11.9-22.1]) compared with DT alone (9.0 months [CI, 4.5-13.5]), p = 0.037. mPFS was also significantly improved with DTP as the initial treatment (11.0 months [CI, 7.0-15.0]) compared with DT alone (4.0 months [CI, 0.7-7.3]), p = 0.049. Twenty-three patients were in the exploratory neoadjuvant group, where mOS was the longest (63.0 months [CI, 15.5-110.5]). No grade 5 adverse events (AEs) occurred in all three cohorts, and 32.4% had immune-related AEs, most frequently hepatitis and colitis. Conclusions: Our results show that in BRAFm-ATC, addition of pembrolizumab to dabrafenib/trametinib may significantly prolong survival. Surgical resection of the primary tumor after initial BRAF-targeted therapy in selected patients may provide further survival benefit. However, conclusions are limited by the retrospective nature of the study. Additional prospective data are needed to confirm this observation.

Current and future of immunotherapy for thyroid cancer based on bibliometrics and clinical trials

BACKGROUND

Thyroid cancer is a leading endocrine malignancy, with anaplastic and medullary subtypes posing treatment challenges. Existing therapies have limited efficacy, highlighting a need for innovative approaches.

METHODS

We analyzed 658 articles and 87 eligible clinical trials using bibliometric tools and database searches, including annual publication and citation trends, were executed using Web of Science, CiteSpace, and VOS Viewer.

RESULTS

Post-2018, there is a surge in thyroid cancer immunotherapy research, primarily from China and the University of Pisa. Of the 87 trials, 32 were Phase I and 55 were Phase II, mostly exploring combination therapies involving immune checkpoint inhibitors.

CONCLUSION

The study's dual approach verifies the swift advancement of thyroid cancer immunotherapy from diverse perspectives. Immune checkpoint inhibitors have become the preferred regimen for advanced MTC and ATC in late therapeutic lines. However, since ICB plays a pivotal role in ATC, current clinical trial data show that ATC patients account for more and the curative effect is more accurate. Anticipated future developments are inclined toward combination regimens integrating immunotherapy with chemotherapy or targeted therapies. Emerging approaches, such as bispecific antibodies, cytokine-based therapies, and adoptive cell therapies like CAR-T and TCR-T, are exhibiting considerable potential. Upcoming research is expected to concentrate on refining the tumor immune milieu and discovering novel biomarkers germane to immunotherapeutic interventions.

Leveraging molecular targeted drugs and immune checkpoint inhibitors treat advanced thyroid carcinoma to achieve thyroid carcinoma redifferentiation

Thyroid cancer can be classified into three different types based on the degree of differentiation: well-differentiated, poorly differentiated, and anaplastic thyroid carcinoma. Well-differentiated thyroid cancer refers to cancer cells that closely resemble normal thyroid cells, while poorly differentiated and anaplastic thyroid carcinoma are characterized by cells that have lost their resemblance to normal thyroid cells. Advanced thyroid carcinoma, regardless of its degree of differentiation, is known to have a higher likelihood of disease progression and is generally associated with a poor prognosis. However, the process through which well-differentiated thyroid carcinoma transforms into anaplastic thyroid carcinoma, also known as "dedifferentiation", has been a subject of intensive research. In recent years, there have been significant breakthroughs in the treatment of refractory advanced thyroid cancer. Clinical studies have been conducted to evaluate the efficacy and safety of molecular targeted drugs and immune checkpoint inhibitors in the treatment of dedifferentiated thyroid cancer. These drugs work by targeting specific molecules or proteins in cancer cells to inhibit their growth or by enhancing the body's immune response against the cancer cells. This article aims to explore some of the possible mechanisms behind the dedifferentiation process in well-differentiated thyroid carcinoma. It also discusses the clinical effects of molecular targeted drugs and immune checkpoint inhibitors in thyroid cancer patients with different degrees of differentiation. Furthermore, it offers insights into the future trends in the treatment of advanced thyroid cancer, highlighting the potential for improved outcomes and better patient care.

Circulating immunophenotypes are potentially prognostic in follicular cell-derived thyroid cancer

Background

Exploring the immune interface of follicular cell-derived thyroid cancer has prognostic and therapeutic potential. The available literature is lacking for comprehensive immunophenotyping in relation to clinical outcomes. In this study, we identify circulating immunophenotypes associated with thyroid cancer prognosis.

Methods

We conducted a pilot observational study of adults with follicular cell-derived thyroid cancer who underwent surgery at our tertiary care referral center and had consented for flow cytometry on peripheral blood collected at the time of thyroidectomy.

Results

Of the 32 included subjects, 20 (62%) had well differentiated, 5 (16%) had poorly differentiated, and 7 (22%) had anaplastic thyroid cancer. The most frequent AJCC stage was 4 (59%) and the ATA risk of recurrence category was high (56%). Patients with AJCC stage 3/4 demonstrated fewer circulating mononuclear cells (CD45+), more monocytes (CD14+), fewer total lymphocytes (CD14-), fewer T cells (CD3+), fewer CD4+ T cells, fewer gamma-delta T cells, fewer natural killer (NK) T-like cells, more myeloid-derived suppressor cells (MDSCs; Lin-CD33+HLADR-), and more effector memory T cells but similar CD8+ T cells compared to stage1/2. Immunophenotype comparisons by ATA risk stratification and course of thyroid cancer were comparable to those observed for stage, except for significant differences in memory T cell subtypes. The median follow-up was 58 months.

Conclusions

Aggressive follicular cell-derived thyroid cancer either at presentation or during follow-up is associated with down-regulation of the T cell populations specifically CD4+ T cells, gamma-delta T cells, and NK T-like cells but up-regulation of MDSCs and altered memory T cells. These immunophenotypes are potential prognostic biomarkers supporting future investigation for developing targeted immunotherapies against advanced thyroid cancer.

Harnessing Immunity to Treat Advanced Thyroid Cancer

The incidence of thyroid cancer (TC) has increased over the past 30 years. Although differentiated thyroid cancer (DTC) has a good prognosis in most patients undergoing total thyroidectomy followed by radioiodine therapy (RAI), 5-10% of patients develop metastasis. Anaplastic thyroid cancer (ATC) has a low survival rate and few effective treatments have been available to date. Recently, tyrosine kinase inhibitors (TKIs) have been successfully applied to RAI-resistant or non-responsive TC to suppress the disease. However, TC eventually develops resistance to TKIs. Immunotherapy is a promising treatment for TC, the majority of which is considered an immune-hot malignancy. Immune suppression by TC cells and immune-suppressing cells, including tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells, is complex and dynamic. Negative immune checkpoints, cytokines, vascular endothelial growth factors (VEGF), and indoleamine 2,3-dioxygenase 1 (IDO1) suppress antitumor T cells. Basic and translational advances in immune checkpoint inhibitors (ICIs), molecule-targeted therapy, tumor-specific immunotherapy, and their combinations have enabled us to overcome immune suppression and activate antitumor immune cells. This review summarizes current findings regarding the immune microenvironment, immunosuppression, immunological targets, and immunotherapy for TC and highlights the potential efficacy of immunotherapy.

Tyrosine Kinase Inhibitors for Radioactive Iodine Refractory Differentiated Thyroid Cancer

Patients with differentiated thyroid cancer usually present with early-stage disease and undergo surgery followed by adjuvant radioactive iodine ablation, resulting in excellent clinical outcomes and prognosis. However, a minority of patients relapse with metastatic disease, and eventually develop radioactive iodine refractory disease (RAIR). In the past there were limited and ineffective options for systemic therapy for RAIR, but over the last ten to fifteen years the emergence of tyrosine kinase inhibitors (TKIs) has provided important new avenues of treatment for these patients, that are the focus of this review. Currently, Lenvatinib and Sorafenib, multitargeted TKIs, represent the standard first-line systemic treatment options for RAIR thyroid carcinoma, while Cabozantinib is the standard second-line treatment option. Furthermore, targeted therapies for patients with specific targetable molecular abnormalities include Latrectinib or Entrectinib for patients with NTRK gene fusions and Selpercatinib or Pralsetinib for patients with RET gene fusions. Dabrafenib plus Trametinib currently only have tumor agnostic approval in the USA for patients with BRAF V600E mutations, including thyroid cancer. Redifferentiation therapy is an area of active research, with promising initial results, while immunotherapy studies with checkpoint inhibitors in combination with tyrosine kinase inhibitors are underway.

Tumor-associated macrophages as a potential therapeutic target in thyroid cancers

Macrophages are important precursor cell types of the innate immune system and bridge adaptive immune responses through the antigen presentation system. Meanwhile, macrophages constitute substantial portion of the stromal cells in the tumor microenvironment (TME) (referred to as tumor-associated macrophages, or TAMs) and exhibit conflicting roles in the development, invasion, and metastasis of thyroid cancer (TC). Moreover, TAMs play a crucial role to the behavior of TC due to their high degree of infiltration and prognostic relevance. Generally, TAMs can be divided into two subgroups; M1-like TAMs are capable of directly kill tumor cells, and recruiting and activating other immune cells in the early stages of cancer. However, due to changes in the TME, M2-like TAMs gradually increase and promote tumor progression. This review aims to discuss the impact of TAMs on TC, including their role in tumor promotion, gene mutation, and other factors related to the polarization of TAMs. Finally, we will explore the M2-like TAM-centered therapeutic strategies, including chemotherapy, clinical trials, and combinatorial immunotherapy.

The Efficacy and Safety of Surufatinib Combined with Anti PD-1 Antibody Toripalimab in Neoadjuvant Treatment of Locally Advanced Differentiated Thyroid Cancer: A Phase II Study

BACKGROUND

Surgery is the primary treatment for locally advanced differentiated thyroid cancer (DTC). However, some locally advanced patients are not candidates for R0/1 resection. There is limited evidence of neoadjuvant treatment in locally advanced DTC. Surufatinib targets multiple kinases, which is efficient, tolerable, and safe in patients with radioiodine-refractory DTC. In addition, surufatinib plus toripalimab (an anti-PD-1 antibody) showed encouraging antitumor activity in advanced solid tumors. This study was designed to evaluate the efficacy and safety of surufatinib plus toripalimab in locally advanced DTC in the neoadjuvant setting.

METHODS

In this single-arm, phase II study, patients with pathologically confirmed unresectable or borderline resectable DTC were eligible and received a combination of 250 mg of surufatinib (orally daily) with 240 mg of toripalimab (intravenous, every 3 weeks). Treatment continued until satisfied for curative surgery, disease progression, withdrawal of consent, unacceptable toxicity, or investigator decision. Primary endpoint was objective response rate (ORR). Secondary endpoints included R0/1 resection rate, adverse events (AEs), etc. RESULTS: Ten patients were enrolled and received at least 4 cycles of treatment. The ORR was 60%. Nine patients received R0/1 resections after neoadjuvant treatment. The median best percentage change in the sum of the target lesion diameter was 32%. Most adverse events (AEs) were grade 1 or 2.

CONCLUSIONS

Surufatinib in combination with toripalimab as neoadjuvant therapy for locally advanced DTC was feasible, and the majority of patients achieved R0/1 resection. It represents a new option for locally advanced DTC and needs further investigation.

Survival Outcomes of Advanced Thyroid Cancer Enriched in Brain Metastases Following Treatment With Small Molecule Inhibitors

OBJECTIVE

Small molecule inhibitors (SMIs) are targeted therapies increasingly used in advanced thyroid carcinomas. This study aimed to evaluate the survival outcomes of thyroid cancer on SMI treatment, including in patients with brain metastases.

METHODS

This retrospective study included patients with thyroid carcinomas who received at least one SMI between 2008 and 2022 at a tertiary level, academic institution. SMI included lenvatinib, sorafenib, dabrafenib-trametinib, selpercatinib, and cabozantinib. Patients were grouped by the presence of brain metastasis. Kaplan-Meier and log-rank tests modeled the overall survival (OS), defined from detection of first metastasis.

RESULTS

In total, 116 patients (49.1% female, median age 61.1 years [IQR, 51.1-71.0]) were included. Thyroid cancer subtypes were: 57 (49.6%) papillary, 23 (19.8%) anaplastic, 23 (19.8%) medullary, and 13 (11.2%) follicular. There were 18 (15.5%) patients with brain metastases, and 98 (84.5%) with visceral metastases. Age, sex, thyroid subtype, SMI, and time to recurrence were not different between cohorts. OS was shorter in the brain metastasis cohort (31.7 vs 42.2 months, P =.44) and was not different after excluding anaplastic thyroid cancer (29.1 vs 62.3 months, P =.21). In the case of papillary thyroid cancer, patients with brain metastases trended toward worse OS (22.0 vs 59.9 months, P =.13). Nonanaplastic histology, total thyroidectomy (OR, 40.0; P <.001), number of unique therapies (OR, 10.9; P =.047), and mutation-directed therapy (OR, 24.7; P =.003) were associated with improved OS.

CONCLUSION

This single-institutional analysis reports survival outcomes of 116 patients with advanced thyroid cancer on targeted therapies, including 18 patients with brain metastases. Mutation-directed therapy for BRAFV600E mutations, RET mutations, RET fusions, and NTRK fusions had superior survival.

New Insights into Immune Cells and Immunotherapy for Thyroid Cancer

Thyroid cancer (TC) is the most common endocrine malignancy worldwide, and the incidence of TC has gradually increased in recent decades. Differentiated thyroid cancer (DTC) is the most common subtype and has a good prognosis. However, advanced DTC patients with recurrence, metastasis and iodine refractoriness, as well as more aggressive subtypes such as poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC), still pose a great challenge for clinical management. Therefore, it is necessary to continue to explore the inherent molecular heterogeneity of different TC subtypes and the global landscape of the tumor immune microenvironment (TIME) to find new potential therapeutic targets. Immunotherapy is a promising therapeutic strategy that can be used alone or in combination with drugs targeting tumor-driven genes. This article focuses on the genomic characteristics, tumor-associated immune cell infiltration and immune checkpoint expression of different subtypes of TC patients to provide guidance for immunotherapy.

Update regarding the role of PD-L1 in oncocytic thyroid lesions on cytological samples

AIMS

Several papers have shown that programmed death-ligand 1 (PD-L1) expression is a relevant predictive biomarker in anti-PD-L1 cancer immunotherapy. While its role in several human cancers is correlated with poor prognosis and resistance to anticancer therapies, in thyroid cancers the role of PD-L1 remains questionable. Few articles have studied PD-L1 in thyroid fine-needle aspiration cytology (FNAC), demonstrating a possible correlation with papillary thyroid carcinoma. However, its role in oncocytic thyroid lesions remains controversial. We accordingly examine the performance of PD-L1 immunostaining in liquid based cytology (LBC) from oncocytic lesions.

METHODS

From January 2019 to March 2021, 114 thyroid lesions diagnosed by FNAC from lesions with a predominant oncocytic component, were enrolled for evaluation by PD-L1 immunostaining on both LBC and corresponding histology samples.

RESULTS

The FNAC cohort included 51 benign (B, negative controls), 4 atypia of undetermined significance/follicular lesions of undetermined significance (AUS/FLUS), 57 follicular lesions (follicular neoplasm/suspicious for FN, FN/SFN) and 2 suspicious for malignancy (SFM) cases. Fifty-four cases (11B, 2 AUS/FLUS, 39 FN/SFN and 2 SFM) had histological follow-up including: 1B case resulted as a hyperplastic oxyphilic nodule in Hashimoto thyroiditis (HT), 10B as goitre, 2 AUS/FLUS cases as oncocytic adenomas (OAs); 39 FN/SFN included 27 OAs, 4 FA and 8 oncocytic follicular carcinoma (OFC). The two SFM cases were diagnosed on histopathology as OAs. Increased plasma membrane and cytoplasmic PD-L1 expression were found in 47 cases of the LBC cases (41.2%). Among the histological series, 67.3% of OAs and 75% of OFC had PD-L1 expression, while negative PD-L1 was found in hyperplastic oncocytic cells in HT. A positivity in more than 30% of the neoplastic cells was found in 72.9% of the cases including six OFC.

CONCLUSIONS

These data suggest that PD-L1 expression is expressed in oncocytic thyroid lesions. While weak PD-L1 expression failed to discriminate benign from malignant lesions, OFC demonstrated more intense cytoplasmic and membranous expression.

METTL3 inhibition induced by M2 macrophage-derived extracellular vesicles drives anti-PD-1 therapy resistance via M6A-CD70-mediated immune suppression in thyroid cancer

The treatment options for advanced papillary thyroid cancer (PTC) and anaplastic thyroid cancer (ATC) refractory to standard therapies are limited. Although anti-PD-1 therapy has a manageable safety profile and has been effective in a small percentage of patients with advanced PTC and refractory ATC, the majority of the patients either do not respond or develop resistance to anti-PD-1 therapy. N6-methyladenosine (m6A) modification is a critical determinant of the complexity of the tumor microenvironment (TME). However, it is unclear whether and how m6A modification in tumor cells shapes the immune landscape of PTC and ATC. In this study, we performed bulk and single cell RNA sequencing analysis of PTC and ATC tissues, and found that low METTL3 expression not only correlated to poor response to immune checkpoint blockade (ICB) but was also associated with increased TNF family-related ligand-receptor interactions in the immunosuppressive Tregs and exhausted T cells. Furthermore, overexpression of METTL3 in PTC and ATC cells enhanced the efficacy of anti-PD-1 therapy in a peripheral blood mononuclear cell humanized NCG (huPBMC-NCG) mouse model. Mechanistically, M2 macrophage-derived extracellular vesicles (M2 EVs) inhibited METTL3 expression in PTC and ATC cells via miR-21-5p. Downregulation of METTL3 promoted demethylation of CD70 mRNA, which prevented YTHDF2-mediated degradation of the transcripts. The stabilization of CD70 mRNA, and the subsequent upregulation in CD70 protein levels increased the abundance of the immunosuppressive Tregs and terminally exhausted T cells, thereby inducing resistance to anti-PD-1 therapy. Furthermore, blocking CD70 using cusatuzumab, a high-affinity monoclonal antibody, reversed the anti-PD-1 therapy resistance induced by M2 EVs in vivo. Finally, we demonstrated that METTL3 expression negatively correlated with CD70 expression and M2 macrophages and Tregs infiltration in PTC and ATC tissues. Our findings provide new insights into developing novel therapies for advanced PTC and ATC.

A clinically useful and biologically informative genomic classifier for papillary thyroid cancer

Clinical management of papillary thyroid cancer depends on estimations of prognosis. Standard care, which relies on prognostication based on clinicopathologic features, is inaccurate. We applied a machine learning algorithm (HighLifeR) to 502 cases annotated by The Cancer Genome Atlas Project to derive an accurate molecular prognostic classifier. Unsupervised analysis of the 82 genes that were most closely associated with recurrence after surgery enabled the identification of three unique molecular subtypes. One subtype had a high recurrence rate, an immunosuppressed microenvironment, and enrichment of the EZH2-HOTAIR pathway. Two other unique molecular subtypes with a lower rate of recurrence were identified, including one subtype with a paucity of BRAFV600E mutations and a high rate of RAS mutations. The genomic risk classifier, in addition to tumor size and lymph node status, enabled effective prognostication that outperformed the American Thyroid Association clinical risk stratification. The genomic classifier we derived can potentially be applied preoperatively to direct clinical decision-making. Distinct biological features of molecular subtypes also have implications regarding sensitivity to radioactive iodine, EZH2 inhibitors, and immune checkpoint inhibitors.

Reduced Tumor Size of Untreated Papillary Thyroid Carcinoma After Immune Checkpoint Inhibitor-Induced Thyroiditis

Background/Objective

Immune checkpoint inhibitors (CPIs) activate antitumoral immune responses and are used to treat multiple types of primary and metastatic malignancies. Thyroid dysfunction is a known immune-related adverse event of CPI therapy. There are few data on the effect of CPI and CPI-induced thyroiditis on primary papillary thyroid carcinoma (PTC). We present a patient who developed CPI-induced thyroiditis during treatment for a nonthyroid malignancy and subsequent regression of a coexisting untreated primary PTC.

Case Report

A 49-year-old man with metastatic colon adenocarcinoma was found to have a large right thyroid nodule with biopsy confirmation of PTC. He did not have compressive symptoms or evidence of metastatic PTC. Resection was not performed because of colon cancer therapy. Treatment with CPI (ezabenlimab, an anti-programmed cell death protein 1 antibody) was initiated for the treatment of colon cancer. Four months after the initiation of CPI therapy, testing showed thyroid-stimulating hormone and free thyroxine levels of 174.9 (0.3-4.0 mIU/L) and 0.67 (0.93-1.70 ng/dL), respectively, consistent with CPI-induced hypothyroidism. Levothyroxine therapy was initiated. Repeat imaging 3 months later demonstrated a decrease in the tumor size to 4.1 × 4.9 × 4.2 cm (calculated volume change, -8.3% from baseline). At the last imaging, 1 year after the onset of CPI-induced thyroiditis, the PTC continued to decrease in size and measured 2.9 × 3.9 × 3.2 cm (volume change, -60.7% from baseline).

Discussion

CPI-induced thyroiditis suggests the development of an immune response against thyroid tissue and may reflect a similar increased immune response against PTC cells leading to tumor regression in this case.

Conclusion

Further research to assess the immunologic mechanism underlying this association is warranted to potentially develop improved immunotherapy for PTC.

PMSG-Net: A priori-guided multilevel graph transformer fusion network for immunotherapy efficacy prediction

In the case of specific immunotherapy regimens and access to pre-treatment CT scans, developing reliable, interpretable intelligent image biomarkers to predict efficacy is essential for physician decision-making and patient treatment selection. However, varying levels of prognosis show a similar appearance on CT scans. It becomes challenging to stratify patients by a single pre-treatment CT scan when presenting subtle differences in images for experienced experts and existing prognostic classification methods. In addition, the pattern of peri-tumoural radiological structures also determines the patient's response to ICIs. Therefore, it is essential to develop a method that focuses on the clinical priori features of the tumour edges but also makes full use of the rich information within the 3D tumour. This paper proposes a priori-guided multilevel graph transformer fusion network (PMSG-Net). Specifically, a graph convolutional network is first used to obtain a feature representation of the tumour edge, and complementary information from that detailed representation is used to enhance the global representation. In the tumour global representation branch (MSGNet), we designed the cascaded scale-enhanced swin transformer to obtain attributes of graph nodes, and efficiently learn and model spatial dependencies and semantic connections at different scales through multi-hop context-aware attention (MCA), yielding a richer global semantic representation. To our knowledge, this is the first attempt to use graph neural networks to predict the efficacy of immunotherapy, and the experimental results show that this method outperforms the current mainstream methods.

Molecular basis and targeted therapy in thyroid cancer: Progress and opportunities

Thyroid cancer (TC) is the most prevalent endocrine malignant tumor. Surgery, chemotherapy, radiotherapy, and radioactive iodine (RAI) therapy are the standard TC treatment modalities. However, recurrence or tumor metastasis remains the main challenge in the management of anaplastic thyroid cancer (ATC) and radioiodine (RAI) radioactive iodine-refractory differentiated thyroid cancer (RR-DTC). Several multi-tyrosine kinase inhibitors (MKIs), or immune checkpoint inhibitors in combination with MKIs, have emerged as novel therapies for controlling the progression of DTC, medullary thyroid cancer (MTC), and ATC. Here, we discuss and summarize the molecular basis of TC, review molecularly targeted therapeutic drugs in clinical research, and explore potentially novel molecular therapeutic targets. We focused on the evaluation of current and recently emerging tyrosine kinase inhibitors approved for systemic therapy for TC, including lenvatinib, sorafenib and cabozantinib in DTC, vandetanib, cabozantinib, and RET-specific inhibitor (selpercatinib and pralsetinib) in MTC, combination dabrafenib with trametinib in ATC. In addition, we also discuss promising treatments that are in clinical trials and may be incorporated into clinical practice in the future, briefly describe the resistance mechanisms of targeted therapies, emphasizing that personalized medicine is critical to the design of second-line therapies.

Analysis of Expression of Programmed Cell Death Ligand 1 (PD-L1) and BRAFV600E Mutation in Thyroid Cancer

In thyroid cancer, it has been suggested that PD-L1 overexpression is associated with some clinicopathological factors and prognosis. The aim of this study is to characterize the expression of PD-L1, the presence of the BRAF^V600E mutation, as well as cellular and humoral immunity in thyroid cancer, and to investigate the factors that predict the effectiveness of anti-PD-L1 antibody therapy. Blood samples were collected from 33 patients who were newly diagnosed with thyroid cancer after surgery or biopsy. PD-L1 expression, BRAF^V600E mutation, and CD8+ expression were examined by immunohistological staining using clinical thyroid cancer specimens. With a PD-L1 staining cut-off value of 1%, 13 (39.4%) patients were classified as PD-L1 positive. Stimulation Index (SI) is an indicator of T cell activation. PD-L1 expression was significantly correlated with low SI level (p = 0.046). Moreover, BRAF^V600E mutation was detected in 24 of the 33 (72.7%) patients, and was significantly associated with PD-L1 expression (p = 0.047). In addition, enhanced CD8+ expression was significantly associated with PD-L1 expression (p = 0.003). Multivariate analyses confirmed that high CRP levels (p = 0.039) were independently and significantly associated with poor progression-free survival. These findings suggest that elevated PD-L1 status can be a prognostic indicator for survival in patients with thyroid cancer when comprehensively assessed using the expression of CD8+, the presence of BRAF^V600E mutation and the patient's immune status.

Review article: new treatments for advanced differentiated thyroid cancers and potential mechanisms of drug resistance

The treatment of advanced, radioiodine refractory, differentiated thyroid cancers (RR-DTCs) has undergone major advancements in the last decade, causing a paradigm shift in the management and prognosis of these patients. Better understanding of the molecular drivers of tumorigenesis and access to next generation sequencing of tumors have led to the development and Food and Drug Administration (FDA)-approval of numerous targeted therapies for RR-DTCs, including antiangiogenic multikinase inhibitors, and more recently, fusion-specific kinase inhibitors such as RET inhibitors and NTRK inhibitors. BRAF + MEK inhibitors have also been approved for BRAF-mutated solid tumors and are routinely used in RR-DTCs in many centers. However, none of the currently available treatments are curative, and most patients will ultimately show progression. Current research efforts are therefore focused on identifying resistance mechanisms to tyrosine kinase inhibitors and ways to overcome them. Various novel treatment strategies are under investigation, including immunotherapy, redifferentiation therapy, and second-generation kinase inhibitors. In this review, we will discuss currently available drugs for advanced RR-DTCs, potential mechanisms of drug resistance and future therapeutic avenues.

BRAF-AXL-PD-L1 Signaling Axis as a Possible Biological Marker for RAI Treatment in the Thyroid Cancer ATA Intermediate Risk Category

The use of radioiodine therapy (RIT) is debated in intermediate-risk differentiated thyroid cancer (DTC) patients. The understanding of the molecular mechanisms involved in the pathogenesis of DTC can be useful to refine patient selection for RIT. We analyzed the mutational status of BRAF, RAS, TERT, PIK3 and RET, and the expression of PD-L1 (as a CPS score), the NIS and AXL genes and the tumor-infiltrating lymphocytes (TIL, as the CD4/CD8 ratio), in the tumor tissue in a cohort of forty-six ATA intermediate-risk patients, homogeneously treated with surgery and RIT. We found a significant correlation between BRAF mutations and a less than excellent (LER, according to 2015 ATA classification) response to RIT treatment (p = 0.001), higher expression of the AXL gene (p = 0.007), lower expression of NIS (p = 0.045) and higher expression of PD-L1 (p = 0.004). Moreover, the LER patient group had a significantly higher level of AXL (p = 0.0003), a lower level of NIS (p = 0.0004) and a higher PD-L1 level (p = 0.0001) in comparison to patients having an excellent response to RIT. We also found a significant direct correlation between the AXL level and PD-L1 expression (p < 0.0001) and a significant inverse correlation between AXL and NIS expression and TILs (p = 0.0009 and p = 0.028, respectively). These data suggest that BRAF mutations and AXL expression are involved in LER among DTC patients and in the higher expression of PD-L1 and CD8, becoming new possible biomarkers to personalize RIT in the ATA intermediate-risk group, as well as the use of higher radioiodine activity or other possible therapies.

Anlotinib combined with Sintilimab is win-win cooperation for primary squamous cell carcinoma of the thyroid: A case report and literature review

Background

Primary squamous cell carcinoma of the thyroid (PSCCT) is a rare malignant tumor. The incidence rate of PSCCT is less than 1%. However, the diagnosis and treatment of PSCCT are limited. Surgical resection is considered to be one of the few effective intervention methods. In this article, we reported a case of taking tyrosine kinase inhibitors (TKIs) combined with immune checkpoint inhibitors (ICIs) for PSCCT.

Case summary

An 80-year-old male was admitted to our hospital with dyspnea, cough, wheezing, and hoarseness for a giant thyroid mass. He underwent bronchoscopy and tracheal stent implantation to alleviate the respiratory obstruction. Then he accepted right partial thyroid and right lymph node biopsy. Postoperative pathology revealed squamous cell carcinoma. Subsequently, he underwent an endoscopy to exclude upper gastrointestinal squamous cell carcinoma. Finally, he was diagnosed with PSCCT. The patient was tentatively treated with a combination of Anlotinib and Sintilimab. After two courses, the tumor volume significantly reduced in MRI images and shrank further after five courses of combined treatment. Unfortunately, the patient died of fulminant liver failure and autoimmune liver disease after 5-month-treatment.

Conclusion

TKIs combined with ICIs may be an effective and novel way for PSCCT treatment, but immune-related complications, especially liver damage, should be cared.

Immunotherapeutic Approaches in Ovarian Cancer

Ovarian cancer (OC) is gynecological cancer, and diagnosis and treatment are continuously advancing. Next-generation sequencing (NGS)-based diagnoses have emerged as novel methods for identifying molecules and pathways in cancer research. The NGS-based applications have expanded in OC research for early detection and identification of aberrant genes and dysregulation pathways, demonstrating comprehensive views of the entire transcriptome, such as fusion genes, genetic mutations, and gene expression profiling. Coinciding with advances in NGS-based diagnosis, treatment strategies for OC, such as molecular targeted therapy and immunotherapy, have also advanced. Immunotherapy is effective against many other cancers, and its efficacy against OC has also been demonstrated at the clinical phase. In this review, we describe several NGS-based applications for therapeutic targets of OC, and introduce current immunotherapeutic strategies, including vaccines, checkpoint inhibitors, and chimeric antigen receptor (CAR)-T cell transplantation, for effective diagnosis and treatment of OC.

Targeting RET alterations in cancer: Recent progress and future directions

Genomic alterations in the receptor tyrosine kinase RET represent actionable driver events in several cancer types. Activation of the kinase domain by point mutations represents a pathognomonic event in medullary thyroid cancer, while RET fusions are critical driver events in a sizable subset of differentiated thyroid cancer and a smaller percentage of lung cancer. Early trials with multi-kinase inhibitors yielded modest improvement in outcomes for RET-driven cancers. In recent years, highly selective RET inhibitors entered clinical trials and demonstrated remarkable response rates, resulting in accelerated approval for selpercatinib and pralsetinib in 2020. An important mechanism of eventual resistance to RET inhibitors is the emergence of secondary drug resistance mutations, particularly in the solvent front, and several promising compounds are in development to overcome these mutations. Mechanisms of acquired resistance that bypass RET signaling altogether have also been discovered, suggesting that combinatorial drug strategies may be necessary for some patients.