Neoadjuvant BRAF- and Immune-Directed Therapy for Anaplastic Thyroid Carcinoma

Effect and Safety of Apatinib as Neoadjuvant Therapy in Locally Advanced Differentiated Thyroid Cancer: A Phase 2 Trial

Context

Presently, there is a paucity of prospective clinical trials investigating neoadjuvant therapy for locally advanced thyroid cancer.

Objective

This study was a multicenter, open-label, single-arm, phase II trial evaluating the efficacy and safety of apatinib as neoadjuvant therapy in patients with local advanced differentiated thyroid cancer (DTC).

Methods

Patients were treated with preoperative apatinib over a course of 2 to 4 cycles, culminating in surgical resection. The primary endpoints were objective response rate (ORR) and disease control rate (DCR); the secondary endpoints were the rate of R0 surgery, alterations in serum thyroglobulin levels, disease-free survival, and adverse events (AEs).

Results

A total of 14 patients who met the inclusion criteria were administered neoadjuvant apatinib. Among these, 13 patients underwent surgical procedures following apatinib treatment and were enrolled in the ITT population. The ORR was 53.8% and the DCR was 100%. Of the patients, 84.6% received R0 surgery, while the remaining 15.4% underwent R1 resection. Predominant among the observed AEs were hypertension, hand-foot syndrome, hepatic dysfunction, proteinuria, and hypothyroidism, with no instances of grade 4 or 5 AEs reported. Subsequent to surgery, patients were followed up for a median period of 34 months, during which disease progression occurred in 5 individuals (35.7%), encompassing 3 cases of locoregional recurrences and 2 cases of distant metastases.

Conclusion

Apatinib may be an effective agent in the use of neoadjuvant therapy for locally advanced DTC. Patients may therefore benefit from surgical outcomes and their long-term prognosis.

PD-L1 Expression and Its Modulating Factors in Anaplastic Thyroid Carcinoma: A Multi-institutional Study

Anti-PD immunotherapy is currently under investigation in anaplastic thyroid carcinoma (ATC). Tumor cell surface PD-L1 expression is considered predictive of therapeutic response. Although papillary thyroid carcinoma has been widely studied for PD-L1 expression, there are limited data on ATC. In this retrospective multi-institutional study involving 9 centers across Asia, 179 ATCs were assessed for PD-L1 expression using the SP263 (Ventana) clone. A tumor proportion score (TPS) ≥1% was required to consider a case PD-L1-positive. PD-L1 expression was compared with the histological patterns, the type of specimen (small or large), tumor molecular profile (BRAF V600E and TERT promoter mutation status), and patient outcome. PD-L1 expression in any co-existent differentiated thyroid carcinoma (DTC) was evaluated separately and compared with ATC. Most ATCs (73.2%) were PD-L1-positive. The median TPS among positive cases was 36% (IQR 11% to 75%; range 1% to 99%). A high expression (TPS ≥ 50%) was noted in 30.7%. PD-L1-negative cases were more likely to be small specimens (P=0.01). A negative result on small samples, hence, may not preclude expression elsewhere. ATCs having epithelioid and pleomorphic histological patterns were more likely to be PD-L1-positive with higher TPS than sarcomatoid (P<0.01). DTCs were more frequently negative and had lower TPS than ATC (P<0.01). Such PD-L1 conversion from DTC-negative to ATC-positive was documented in 71% of cases with co-existent DTC. BRAF V600E, but not TERT promoter mutations, correlated significantly with PD-L1-positivity rate (P=0.039), reinforcing the potential of combining anti-PD and anti-BRAF V600E drugs. PD-L1 expression, however, did not impact the patient outcome.

Combined radiation and chemotherapy versus monotherapy for anaplastic thyroid cancer: A SEER retrospective analysis

Background

The effect of combined radiation and chemotherapy (combination therapy) versus monotherapy on anaplastic thyroid carcinoma (ATC) has not yet been clear.

Methods

We identified 516 ATC patients during 2010-2015 from the Surveillance, Epidemiology and End Results (SEER) database and evaluated their survival outcome using the Kaplan-Meier method, Cox regression analysis and propensity score matching (PSM) technique.

Results

The median overall survival (OS) among the entire cohort was 3 months (95 % confidence interval [CI], 2.58-3.42 months), and the 6- and 12-month OS rates were 29 % (95 % CI, 25.01%-32.88 %) and 13 % (95 % CI, 10.60%-16.58 %), respectively. Multivariable analysis demonstrated that ATC patients not receiving radiotherapy or chemotherapy were unquestionably associated with worse OS (hazard ratio [HR] 3.000, 95 % CI, 2.390-3.764) and cancer-specific survival (CSS) (HR = 3.107, 95 % CI, 2.388-4.043), compared with those receiving combination therapy. However, combination therapy did not predict better prognosis compared with monotherapy (all P > 0.05). After PSM, the median OS and CSS were also not significantly improved in patients undergoing chemoradiotherapy versus chemotherapy alone (OS, P = 0.382; CSS, P = 0.420) or radiotherapy alone (OS, P = 0.065; CSS, P = 0.251).

Conclusion

Combination therapy, compared to monotherapy, does not have the expected improvement in survival beyond the benefits achievable with each single-modality treatment, necessitating further prospective research to tailor its treatment management.

Initial Management of BRAF V600E-Variant Anaplastic Thyroid Cancer: The FAST Multidisciplinary Group Consensus Statement

Importance

BRAF/MEK inhibitors revolutionized the treatment of BRAF V600E-variant anaplastic thyroid carcinoma (BRAFv-ATC), offering improved outcomes for patients with this previously incurable disease.

Observations

Anaplastic thyroid carcinoma (ATC) accounts for approximately half of thyroid cancer-related deaths. It presents as a rapidly growing tumor that often invades locoregional structures and spreads to distant sites early; therefore, prompt diagnosis, staging, and treatment initiation are of the essence in the treatment of ATC. Although most oncologists will encounter a patient with ATC in their practice, the rarity of this disease makes treatment challenging, particularly because those with BRAFv-ATC no longer have a dismal prognosis. BRAF/MEK kinase inhibitors have transformed the outlook and treatment of BRAFv-ATC. Therefore, molecular profiling to identify these patients is critical. More recently, the addition of immunotherapy to BRAF/MEK inhibitors as well as the use of the neoadjuvant approach were shown to further improve survival outcomes in BRAFv-ATC. Many of these recent advances have not yet been incorporated in the currently available guidelines, allowing for disparities in the treatment of patients with BRAFv-ATC across the US. With the increasing complexity in the management of BRAFv-ATC, this Consensus Statement aims to formulate guiding recommendations from a group of experts to facilitate therapeutic decision-making.

Conclusions and Relevance

This Consensus Statement from the FAST (Facilitating Anaplastic Thyroid Cancer Specialized Treatment) group at MD Anderson Cancer Center emphasizes that rapid identification of a BRAF V600E pathogenic variant and timely initiation of sequential therapy are critical to avoid excess morbidity and mortality in patients with BRAFv-ATC. In the past decade, remarkable progress has been made in the treatment of patients with BRAFv-ATC, justifying these new evidence-based recommendations reached through a consensus of experts from a high-volume center.

Promising Therapeutic Targets for Recurrent/Metastatic Anaplastic Thyroid Cancer

OPINION STATEMENT

Anaplastic thyroid cancer presents formidable challenges, particularly in cases of recurrence or metastasis. Timely BRAF V600E testing is imperative at diagnosis, initially through immunohistochemistry, followed by comprehensive genomic profiling encompassing genes such as NTRK, RET, ALK, and assessment of tumor mutation burden (TMB). FDA-approved treatment options include dabrafenib and trametinib for patients with BRAF mutations, while those exhibiting high TMB may benefit from pembrolizumab. Further therapeutic decisions hinge upon mutational profile, urgency of response required, airway integrity, and access to targeted therapies There is growing use of immunotherapy for ATC based on published reports of activity, but currently there is no FDA approved agent for ATC. The off-label utilization of "precision medicine" combinations imposes a considerable financial strain, underscoring the necessity for further clinical trials to elucidate promising therapeutic avenues for this orphan disease. There is a pressing need for the development and support of clinical trials investigating genomically driven and immune-based therapies for anaplastic thyroid cancer.

Surgery combined with adjuvant radiation and chemotherapy prolonged overall survival in stage IVC anaplastic thyroid cancer: a SEER-based analysis

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is a rare but aggressive malignancy, which accounts for only 1-2% of all thyroid cancers. The median overall survival (OS) time for all stages patients is at about 5 months. The benefit of surgery combined with adjuvant radiation and chemotherapy in stage IVC anaplastic thyroid cancer is still controversial. The aim of this study is to investigating surgery combined with adjuvant radiation and chemotherapy and survival outcomes in stage IVC ATC patients.

METHOD

Anaplastic thyroid carcinoma patients from the Surveillance, Epidemiology, and End Results database from 2004 to 2016 were used to conduct a cross-sectional study in the analysis. The endpoint of this study was overall survival.

RESULTS

The median OS of the overall population was 2.0 months. Multivariate analysis showed that age (<67 vs. ≥67 years old, P = 0.017, HR = 1.355, 95% CI: 1.057-1.738), tumor size (<7 cm vs. ≥7 cm, P = 0.001, HR = 1.579, 95% CI: 1.202-2.073), Surgery (thyroidectomy vs. non-surgery, P < 0.001, HR = 0.554, 95% CI: 0.401-0.766), radiation therapy (P < 0.001, HR = 0.571, 95% CI: 0.445-0.733) and chemotherapy (P = 0.003, HR = 0.684, 95% CI: 0.531-0.881) were independent prognostic factor for worse OS in stage IVC ATC patients. Surgery combined with adjuvant radiation and chemotherapy exhibited the better overall survival time for 4 months.

CONCLUSIONS

Surgery combined with adjuvant radiation and chemotherapy can improve overall survival in stage IVC ATC patients. We recommend surgical approach with fully evaluation combined with radiation therapy and chemotherapy for selected stage IVC ATC patients.

Nearly Half of Patients with Anaplastic Thyroid Cancer May Be Amenable to Immunotherapy

IMPORTANCE

Poorly differentiated cancer (PDC) and anaplastic thyroid cancer (ATC) have an aggressive course of disease with limited treatment options. The expression of programmed cell death ligand-1 (PD-L1) has been used to determine the responses of many cancers to immunotherapy. The aim of the study was to investigate the expression of PD-L1 in a cohort of patients with PDC and ATC to assess their suitability for immunotherapy. Data, settings, and participants: This study is a retrospective cohort review of patients treated for PDC and ATC treated at a tertiary referral institution during the period 2000-2020. PD-L1 22C3 pharmDx qualitative immunohistochemistry was performed on formalin-fixed, paraffin-embedded (FFPE) specimens of tumours to detect the presence of the PD-L1 protein.

MAIN OUTCOME MEASURES

The percentage of tumours that were positive for PD-L1 immunohistochemistry and the PD-L1 protein expression as measured by using the Tumour Proportion Score (TPS). Secondary outcomes studied were the associations between demographic, clinicopathological, treatment and disease outcomes and PD-L1 expression.

RESULTS

Nineteen patients (12F:7M) with a mean age of 65.4 (±14.3 SD) years were diagnosed with PDC in 4 (21%) and fifteen were diagnosed with ATC (79%) during the study period. Fifteen (79%) patients underwent some form of surgery, with R0 resection achieved in only three of the fifteen (20%) patients. Overall, PD-L1 expression was seen in seven of the fifteen (47%) of the patients with ATC, with no positivity seen in the patients with PDC. PD-L1 expression had no impact on treatment modality and positive expression was not significantly associated with stage of disease, metastasis, or survival.

CONCLUSION

Nearly half of patients with ATC express PD-L1 and may be amenable to immunotherapy with pembrolizumab.

The role of targeted therapy and/or immunotherapy therapy in anaplastic thyroid carcinoma

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is a highly invasive malignant tumor with a poor prognosis. Traditional treatment methods have not been effective. However, advancements in targeted therapy and immunotherapy in recent years have shed new light on the management of ATC. The aim of this study was to examine the treatment plan and prognostic factors of ATC.

METHODS

This study conducted a retrospective analysis of ATC patients who received treatment at our institution between 2000 and 2023 to evaluate the clinical characteristics, treatment methods, and factors influencing survival. Survival analysis was performed by the Kaplan‒Meier method and log-rank test, and multivariate analysis was performed using the Cox proportional hazard model.

RESULTS

The 6-month and 1-year disease-specific OS rates were 49% and 29%, respectively. The presence of clinical symptoms and the timing of treatment significantly impacted patient prognosis (P < 0.05). Compared with surgery + radiotherapy/chemotherapy and only surgery, targeted therapy and targeted + immunotherapy represented an improved overall survival, The 6-month/1-year survival rates of which were 81%/61% and 91%/73% (P < 0.05), respectively. Multivariate analysis indicated that the symptoms at initial diagnosis, year of presentation, performance status and treatment plan were independent factors affecting the prognosis. The year of presentation (P = 0.048) and the treatment plan (P = 0.038) were significantly meaningful in predicting prognosis.

CONCLUSION

Targeted therapy and targeted+immune therapy can effectively prolong the survival period of ATC patients. Symptoms at initial diagnosis and treatment plan have a significant impact on the prognosis.

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.

Efficacy and safety of BRAF/MEK inhibitors in BRAFV600E-mutated anaplastic thyroid cancer: a systematic review and meta-analysis

PURPOSE

Approximately 45% of anaplastic thyroid cancer (ATC) patients harbor a BRAFV600E mutation and are eligible for target therapy (TT) with BRAF and MEK inhibitors (BRAFi/MEKi), nevertheless, few data advocate for this. Hence, we've conducted a systematic review and meta-analysis investigating the effectiveness and safety of BRAFi/MEKi in BRAFV600E ATC patients.

METHODS

PubMed, Embase, and the Cochrane Library were systematically searched for BRAFi/MEKi TT in BRAFV600E ATC patients. Outcomes included objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), duration of response (DOR) and adverse events (AEs).

RESULTS

Nine studies with 168 patients were included. Median follow-up ranged from 2.0 to 47.9 months. 75% of patients had stage IVc. In a pooled analysis, ORR was 68.15% (95% CI 55.31-80.99, I2 = 47%) and DCR was 85.39% (95% CI 78.10-92.68, I2 = 0), with a median DOR of 14.4 months (95% CI 4.6-14.4) and a median PFS of 6.7 months (95% CI 4.7-34.2). Moreover, 1-year OS rate was 64.97% (95% CI 48.76-81.17, I2 = 84%) and 2-years OS rate was 52.08% (95% CI 35.71-68.45, I2 = 79%). Subgroup analysis showed patients in the neoadjuvant setting had higher rates of 1 and 2-years OS and observational studies tended to report higher rates of ORR than clinical trials. No new or unexpected adverse events were found.

CONCLUSIONS

Our study demonstrated BRAFi/MEKi have a decent activity for BRAFV600E ATC patients, especially in the neoadjuvant setting, with a tolerable safety profile. However, further clinical trials are warranted to investigate these findings.

[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.

Integration of scRNA and bulk RNA-sequence to construct the 5-gene molecular prognostic model based on the heterogeneity of thyroid carcinoma endothelial cell

Thyroid cancer (TC) is a kind of cancer with high heterogeneity, which leads to significant difference in prognosis. The prognostic molecular processes are not well understood. Cancer cells and tumor microenvironment (TME) cells jointly determine the heterogeneity. However, quite a little attention was paid to cells in the TME in the past years. In this study, we not only reveal that endothelial cells (ECs) are strongly associated with the progress of papillary thyroid cancer (PTC) using single-cell RNA-seq (scRNA-seq) data downloaded from Gene Expression Omnibus (GEO) and WGCNA, but also screen 5 crucial genes of ECs: CLDN5, ABCG2, NOTCH4, PLAT, and TMEM47. Furthermore, the 5-gene molecular prognostic model is constructed, which can predict how well a patient will do on PD-L1 blockade immunotherapy for TC and evaluate prognosis. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrates that PLAT is decreased in TC and the increase of PLAT can restrain the migratory capacity of TC cells. Meanwhile, in TC cells, PLAT suppresses VEGFa/VEGFR2-mediated human umbilical vascular endothelial cell (HUVEC) proliferation and tube formation. Totally, we construct the 5-gene molecular prognostic model from the perspective of EC and provide a new idea for immunotherapy of TC.

First effectiveness data of lenvatinib and pembrolizumab as first-line therapy in advanced anaplastic thyroid cancer: a retrospective cohort study

BACKGROUND

Anaplastic thyroid cancer (ATC) is a rare and aggressive neoplasm. We still lack effective treatment options, so survival rates remain very low. Here, we aimed to evaluate the activity of the combination of lenvatinib and pembrolizumab as systemic first-line therapy in ATC.

METHODS

In a retrospective analysis, we investigated the activity and tolerability of combined lenvatinib (starting dose 14 to 24 mg daily) and pembrolizumab (200 mg every three weeks) as first-line therapy in an institutional cohort of ATC patients.

RESULTS

Five patients with metastatic ATC received lenvatinib and pembrolizumab as systemic first-line therapy. The median progression-free survival was 4.7 (range 0.8-5.9) months, and the median overall survival was 6.3 (range 0.8-not reached) months. At the first follow-up, one patient had partial response, three patients had stable disease, and one patient was formally not evaluable due to interference of assessment by concomitant acute infectious thyroiditis. This patient was then stable for more than one year and was still on therapy at the data cutoff without disease progression. Further analyses revealed deficient DNA mismatch repair, high CD8+ lymphocyte infiltration, and low macrophage infiltration in this patient. Of the other patients, two had progressive disease after adverse drug reactions and therapy de-escalation, and two died after the first staging. For all patients, the PD-L1 combined positive score ranged from 12 to 100%.

CONCLUSIONS

The combination of lenvatinib and pembrolizumab was effective and moderately tolerated in treatment-naïve ATC patients with occasional long-lasting response. However, we could not confirm the exceptional responses for this combination therapy reported before in pretreated patients.

Knowledge mapping of anaplastic thyroid cancer treatments: a bibliometric analysis (2000-2023)

Context

Anaplastic thyroid cancer (ATC) is a relatively rare and extensively malignant kind of thyroid carcinoma. The poor prognosis and high mortality rate of ATC can be attributed to its invasive features and undifferentiated phenotype. At present, there is a lack of efficacious therapeutic options. In light of the elevated fatality rate, it is vital to possess a comprehensive comprehension of the scientific terrain pertaining to ATC. To gather the perspectives of different researchers about the topic of ATC treatment, we did a bibliometric network analysis, which offers a comprehensive view of the scholarly literature.

Methodology

A systematic search was conducted on the WoSCC database to identify publications pertaining to ATC treatment between the years 2000 and 2023. In this bibliometric investigation, the tools VOSviewers, CiteSpace, and the R package "bibliometrix" were employed to investigate the general attributes, developmental framework, and academic frontiers of the subject matter.

Results

1223 publications in total, written by 6937 scholars from 53 areas and 1402 institutions and published in 358 scholarly journals, were analyzed. There has been a gradual increase in the quantity of publications pertaining to ATC treatment. The United States and China emerged as the most prominent nations. The University of Texas MD Anderson Cancer Center and Memorial Sloan Kettering Cancer Counseling Center are prominent research institutions in highly productive countries. The journal Thyroid holds a prominent position within its discipline, being widely recognized as both the most popular and highly co-cited publication. According to the available data, Maria Cabanillas has authored the highest number of published articles, while RC Smallridge has received the highest number of co-citations. It turned out that the prevailing keywords encompassed expression, therapy, apoptosis, survival, activation, proliferation, metastasis, and other related terms. Immunotherapy, targeted therapy, and prognostic factors are the emerging research hotspots and trends.

Conclusions

This paper presents a complete overview of research trends and advancements in the treatment of ATC using bibliometric analysis. The acquisition of information will offer vital insights for funding and potential creative strategies in researching the treatment of ATC, which indicates the research frontiers as well as prevalent directions in recent years.

Canine thyroid carcinomas: A review with emphasis on comparing the compact subtype of follicular thyroid carcinomas and medullary thyroid carcinomas

Canine thyroid carcinomas are relatively common malignant endocrine neoplasms in dogs derived from either thyroid follicular cells (forming follicular thyroid carcinomas) or medullary cells (parafollicular, C-cells; forming medullary thyroid carcinomas). Older and recent clinical studies often fail to discriminate between compact cellular (solid) follicular thyroid carcinomas and medullary thyroid carcinomas, which may skew conclusions. The compact subtype of follicular thyroid carcinomas appears to be the least differentiated subtype of follicular thyroid carcinomas and needs to be differentiated from medullary thyroid carcinomas. This review includes information on the signalment, presentation, etiopathogenesis, classification, histologic and immunohistochemical diagnosis, clinical management, and biochemical and genetic derangements of canine follicular and medullary carcinomas, and their correlates with human medicine.

The role of surgery for anaplastic thyroid carcinoma in the era of targeted therapeutics: A scoping review

Background

Questions exist regarding patient selection for surgery in anaplastic thyroid carcinoma (ATC), particularly with the advent of neoadjuvant-targeted therapeutics. The present scoping review sought to evaluate what extent of surgical resection should be performed in ATC.

Methods

A scoping review was carried out in accordance with Joanna Briggs Institute and the preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) protocols. Included studies were required to provide clear description of the surgery performed for ATC.

Results

The final search identified 6901 articles. Ultimately only 15 articles including 1484 patients met inclusion criteria. A total of 765 patients (51.5%) underwent attempted curative intent surgery. The approach to resection of adjacent tissues varied between studies. Eight studies considered laryngeal ± pharyngeal resection (8/15, 53.3%), eight studies (53.3%) considered tracheal resection and again eight studies (53.3%) considered esophageal resection. More extensive resections increased morbidity without improving overall survival (OS) (<9 months in the 12 studies using a combination of surgery and chemoradiotherapy). In the three studies utilizing targeted therapy in addition to surgery, OS was notably improved while surgical resection following neoadjuvant therapy was less extensive.

Conclusions

There is no clear agreement in the literature regarding the limits of surgical resection in locoregionally advanced ATC. A definition of surgically resectable disease will be required to guide surgical decision making in ATC, particularly with the potential to reduce tumor burden using neoadjuvant targeted treatment in suitable patients.

Level of evidence

III.

Anaplastic thyroid cancer: Pathogenesis, prognostic factors and genetic landscape (Review)

Anaplastic thyroid cancer (ATC) is a rare and aggressive form of thyroid malignancy, presenting significant challenges in diagnosis and treatment. The rarity of this cancer and its aggressive nature make an accurate diagnosis difficult, requiring a multidisciplinary approach and various imaging techniques. Treatment involves a personalized multimodal approach, including surgery, adjuvant therapies and risk stratification. Prognostic factors such as age, tumor characteristics and genetic alterations play a crucial role in determining patient outcomes. Despite advancements, gaps remain in understanding the underlying mechanisms of the disease and establishing standardized treatment guidelines. Further research, collaborative efforts and multicenter studies are necessary to improve diagnostic accuracy, develop targeted therapies and biomarkers, and enhance the long-term management. The present review provides a comprehensive overview of ATC, discussing its clinical manifestations, diagnostic approaches, treatment options, prognostic factors and genetic landscape.

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.

CDK4 phosphorylation status and rational use for combining CDK4/6 and BRAF/MEK inhibition in advanced thyroid carcinomas

Background

CDK4/6 inhibitors (CDK4/6i) have been established as standard treatment against advanced Estrogen Receptor-positive breast cancers. These drugs are being tested against several cancers, including in combinations with other therapies. We identified the T172-phosphorylation of CDK4 as the step determining its activity, retinoblastoma protein (RB) inactivation, cell cycle commitment and sensitivity to CDK4/6i. Poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinomas, the latter considered one of the most lethal human malignancies, represent major clinical challenges. Several molecular evidence suggest that CDK4/6i could be considered for treating these advanced thyroid cancers.

Methods

We analyzed by two-dimensional gel electrophoresis the CDK4 modification profile and the presence of T172-phosphorylated CDK4 in a collection of 98 fresh-frozen tissues and in 21 cell lines. A sub-cohort of samples was characterized by RNA sequencing and immunohistochemistry. Sensitivity to CDK4/6i (palbociclib and abemaciclib) was assessed by BrdU incorporation/viability assays. Treatment of cell lines with CDK4/6i and combination with BRAF/MEK inhibitors (dabrafenib/trametinib) was comprehensively evaluated by western blot, characterization of immunoprecipitated CDK4 and CDK2 complexes and clonogenic assays.

Results

CDK4 phosphorylation was detected in all well-differentiated thyroid carcinomas (n=29), 19/20 PDTC, 16/23 ATC and 18/21 thyroid cancer cell lines, including 11 ATC-derived ones. Tumors and cell lines without phosphorylated CDK4 presented very high p16CDKN2A levels, which were associated with proliferative activity. Absence of CDK4 phosphorylation in cell lines was associated with CDK4/6i insensitivity. RB1 defects (the primary cause of intrinsic CDK4/6i resistance) were not found in 5/7 tumors without detectable phosphorylated CDK4. A previously developed 11-gene expression signature identified the likely unresponsive tumors, lacking CDK4 phosphorylation. In cell lines, palbociclib synergized with dabrafenib/trametinib by completely and permanently arresting proliferation. These combinations prevented resistance mechanisms induced by palbociclib, most notably Cyclin E1-CDK2 activation and a paradoxical stabilization of phosphorylated CDK4 complexes.

Conclusion

Our study supports further clinical evaluation of CDK4/6i and their combination with anti-BRAF/MEK therapies as a novel effective treatment against advanced thyroid tumors. Moreover, the complementary use of our 11 genes predictor with p16/KI67 evaluation could represent a prompt tool for recognizing the intrinsically CDK4/6i insensitive patients, who are potentially better candidates to immediate chemotherapy.

PD-1 receptor outside the main paradigm: tumour-intrinsic role and clinical implications for checkpoint blockade

Blocking the inhibitory receptor PD-1 on antitumour T lymphocytes is the main rationale underlying the clinical successes of cancer immunotherapies with checkpoint inhibitor (CI) antibodies (Abs). Besides this main paradigm, there is recent evidence of unconventional and "ectopic" signalling pathways of PD-1, found to be expressed not only by lymphocytes but also by peculiar subsets of cancer cells. Several groups reported on the tumour-intrinsic role of PD-1 in multiple settings, including melanoma, hepatocellular, thyroid, lung, pancreatic and colorectal cancer. Its functional activity appears intriguing but is not yet conclusively clarified. The initial studies are, in fact, supporting either a pro-tumourigenic role involved in chemoresistance and disease relapse or, oppositely, tumour-suppressive functions. The implications connected to the therapeutic administration of PD-1 blocking Abs are, of course, potentially relevant, respectively inferring an anti-tumour activity contrasting PD-1+ tumourigenic cells or a pro-tumoural effect by tackling PD-1 tumour suppressive signalling. The progressive exploration and consideration of this new paradigm of tumour-intrinsic PD-1 signalling may improve the interpretation of the observed clinical effects by anti-PD-1 Abs, likely resulting from multiple cumulative activities, and might provide important bases for dedicated clinical studies that take into account such composite roles of PD-1.

History of Thyroid Surgery in the Last Century

Before the 20th century, thyroid surgery was regarded as "horrid butchery" such that no honest and sensible surgeon would ever engage in it. Yet, by the mid-20th century, thyroidectomy had become a respected, life-saving, safe, and increasingly practiced operation. From Kocher to Wells and onward into the 21st century, the evolution of thyroid surgery has continued, enhanced by the integration of endocrinology, genetics, immunology, physiology, technology, training, and multidisciplinary care. The ability to personalize and optimize the care of thyroid disorders has been progressively achieved through shared insights and discoveries, highlights of which are described herein.

Pathogenesis of cancers derived from thyroid follicular cells

The genomic simplicity of differentiated cancers derived from thyroid follicular cells offers unique insights into how oncogenic drivers impact tumour phenotype. Essentially, the main oncoproteins in thyroid cancer activate nodes in the receptor tyrosine kinase-RAS-BRAF pathway, which constitutively induces MAPK signalling to varying degrees consistent with their specific biochemical mechanisms of action. The magnitude of the flux through the MAPK signalling pathway determines key elements of thyroid cancer biology, including differentiation state, invasive properties and the cellular composition of the tumour microenvironment. Progression of disease results from genomic lesions that drive immortalization, disrupt chromatin accessibility and cause cell cycle checkpoint dysfunction, in conjunction with a tumour microenvironment characterized by progressive immunosuppression. This Review charts the genomic trajectories of these common endocrine tumours, while connecting them to the biological states that they confer.

Modulation of EZH2 Activity Induces an Antitumoral Effect and Cell Redifferentiation in Anaplastic Thyroid Cancer

Anaplastic thyroid cancer (ATC) is a rare and lethal form of thyroid cancer that requires urgent investigation of new molecular targets involved in its aggressive biology. In this context, the overactivation of Polycomb Repressive Complex 2/EZH2, which induces chromatin compaction, is frequently observed in aggressive solid tumors, making the EZH2 methyltransferase a potential target for treatment. However, the deregulation of chromatin accessibility is yet not fully investigated in thyroid cancer. In this study, EZH2 expression was modulated by CRISPR/Cas9-mediated gene editing and pharmacologically inhibited with EZH2 inhibitor EPZ6438 alone or in combination with the MAPK inhibitor U0126. The results showed that CRISPR/Cas9-induced EZH2 gene editing reduced cell growth, migration and invasion in vitro and resulted in a 90% reduction in tumor growth when EZH2-edited cells were injected into an immunocompromised mouse model. Immunohistochemistry analysis of the tumors revealed reduced tumor cell proliferation and less recruitment of cancer-associated fibroblasts in the EZH2-edited tumors compared to the control tumors. Moreover, EZH2 inhibition induced thyroid-differentiation genes' expression and mesenchymal-to-epithelial transition (MET) in ATC cells. Thus, this study shows that targeting EZH2 could be a promising neoadjuvant treatment for ATC, as it promotes antitumoral effects in vitro and in vivo and induces cell differentiation.

Challenges and strategies to combat resistance mechanisms in thyroid cancer therapeutics

BACKGROUND

BRAF V600E and K/N/H RAS mutations and oncogenic kinase fusions involving NTRK, RET, ALK and ROS1 have been identified as actionable targets in thyroid cancer. These driver alterations lead to onocogene addiction which has been successfully exploited through tyrosine kinase inhibitors. Acquired resistance may develop following an initial response requiring a therapeutic pivot to new therapies.

SUMMARY

Several pathways for development of acquired resistance have been identified. These encompass acquired on-target gene mutation impeding drug activity and upregulation of bypass kinase signaling pathways leading to tumour progression. Biopsy of resistant lesions (liquid or tissue) and subsequent molecular analysis can assist with new therapeutic strategies.

CONCLUSIONS

Progression-free survival is curtailed by developing acquired resistance. To minimise this therapeutic liability, clinicians must be anticipatory in identifying the drivers and characterising mechanisms of on target resistance.

Mutation-based, short-term "neoadjuvant" treatment allows resectability in stage IVB and C anaplastic thyroid cancer

INTRODUCTION

Few available data indicate that a mutation-based "neoadjuvant" therapy in advanced anaplastic thyroid carcinoma (ATC) might convert an initially unresectable primary tumor to resectable and optimize local tumor control. We evaluated a preoperative short-term "neoadjuvant" therapy with a BRAF-directed therapy or, in case of BRAF non-mutated tumors, an mKI/checkpoint inhibitor combination in three patients with ATC stage IVB and C.

METHODS

In the context of preoperative diagnostics, immunohistochemistry (IHC) assessment and genetic analysis was started as soon as possible. The antiangiogenetic therapy with lenvatinib was immediately after diagnosis of ATC started as bridging therapy. In case of a BRAF-mutated ATC, a combination therapy of dabrafenib and trametinib, in case of BRAF-wildtype ATC a combination of pembrolizumab and lenvatinib was given for 4 weeks. If re-staging has shown a significant therapy response due to a decrease in size of > 50%, surgical resection was reconsidered. A primary tumor resection was performed first. As a second step, limited distant metastasis have been resected approximately 4 weeks after thyroid surgery. After postoperative recovery, the targeted systemic therapy was continued.

PATIENTS

Two patients presented with BRAF-wildtype ATC stage IVC, one with BRAF-mutated ATC stage IVB. All patients were evaluated by surgery, nuclear medicine and oncology upon diagnosis of ATC.

RESULTS

In all three cases, the "neoadjuvant" therapy induced a dramatic response and led to local resectability in primarily non-resectable ATC stage IVB or C. We have chosen for the first time a short-term "neoadjuvant" treatment period to reduce the risk of bleeding and/or fistula due to potential rapid tumor shrinkage. The results of surgery after only short-term "neoadjuvant" therapy showed two R0 und one R1 resections. Postoperative histopathological findings confirmed an extent of tumor necrosis or regressive fibrotic tissue between 60 and > 95% in our patients.

CONCLUSIONS

A short-term mutation-based "neoadjuvant" therapy can achieve local resectability in initially unresectable ATC stage IVB or C. A neoadjuvant treatment period of about 4 weeks seems to show similar response as a treatment duration of at least 3 months.

Pathologic complete response after neoadjuvant v-Raf murine sarcoma viral oncogene homolog B (BRAF) inhibition combined with immunotherapy therapy for anaplastic thyroid carcinoma: a case report and literature review

Anaplastic thyroid carcinoma (ATC) is a highly malignant tumor with invasive nature. Most patients present with locally advanced and/or distant metastatic diseases that are difficult to treat. We report a case of a previously inoperable patient with v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutated ATC. After a trial of neoadjuvant Dabrafenib/Trametinib with immunotherapy, the tumor became operable, and surgical pathology indicated a pathologic complete response (pCR). We also reviewed cases from the literature that utilized neoadjuvant BRAF-directed therapy in ATCs. These cases emphasize that BRAF-and immune-directed therapy is a feasible option in patients with inoperable ATC and may lead to improved outcomes.

Dabrafenib and Trametinib Therapy for Advanced Anaplastic Thyroid Cancer - Real-World Outcomes From UK Centres

AIMS

Anaplastic thyroid cancer (ATC) is a rare but aggressive form of thyroid cancer with a median survival of 4 months. Recent advances in molecular profiling have shown that up to half of ATCs harbour the BRAF-V600E mutation. The aim of this study was to provide real-world data and experience on the use of combination therapy dabrafenib and trametinib in patients with BRAF-V600E-mutated advanced ATC.

MATERIALS AND METHODS

We retrospectively evaluated patients with confirmed BRAF-V600E-mutated ATC, defined as patients with locally advanced or metastatic ATC with no locoregional, radical treatment options. Outcomes measured were overall survival, progression-free survival, response rate, discontinuation rate, dose reduction rate and toxicity data.

RESULTS

Seventeen patients were evaluated and the mean age was 68 years. Ten patients died by the time of censoring. The median duration of follow-up was 12 months (3-43 months). The estimated median overall survival was 6.9 months (95% confidence interval 2.46 months - upper confidence interval not reached) and the median progression-free survival was 4.7 months (95% confidence interval 1.4-7.8 months). Dose interruptions and/or reductions were common, but none of the patients had to permanently discontinue treatment because of toxicities. Severe toxicities (grades 3 and 4) were uncommon.

CONCLUSIONS

This study supports the indication of dabrafenib and trametinib in BRAF-V600E-mutated ATC as an effective and well-tolerated treatment in an historically difficult to treat cancer.

Kinase inhibitors in thyroid cancers

Objective

The treatment landscape for thyroid cancers has changed rapidly with the availability of kinase inhibitors against VEGFR, BRAF, MEK, NTRK, and RET. We provide an up-to-date review of the role of kinase inhibitors in thyroid cancer and discuss upcoming trials.

Design & Methods

A comprehensive review of the available literature describing kinase inhibitors in thyroid cancer was performed.

Results and Conclusions

Kinase inhibitors have become the standard of care for patients with metastatic radioactive iodine-refractory thyroid cancer. Short-term treatment can re-sensitize differentiated thyroid cancer to radioactive iodine, thereby potentially improving outcomes and sparing toxicities associated with the long-term use of kinase inhibitors. The approval of cabozantinib as salvage therapy for progressive radioactive iodine-refractory differentiated thyroid cancer following failure with sorafenib or lenvatinib adds to the available armamentarium of active agents. Vandetanib and cabozantinib have become mainstay treatments for metastatic medullary thyroid cancer regardless of RET mutation status. Selpercatinib and pralsetinib, potent and selective receptor kinase inhibitors with activity against RET, have revolutionized the treatment paradigm for medullary thyroid cancers and other cancers with driver mutations in RET. Dabrafenib plus trametinib for BRAF mutated anaplastic thyroid cancer provides an effective treatment option for this aggressive cancer with a dismal prognosis. In order to design the next generation of agents for thyroid cancer, future efforts will need to focus on developing a better understanding of the mechanisms of resistance to kinase inhibition including bypass signaling and escape mutations.

Anaplastic thyroid carcinoma: advances in molecular profiling and targeted therapy

PURPOSE OF REVIEW

Anaplastic thyroid carcinomas (ATCs) are rare cancers with a globally very poor prognosis, because of their immensely aggressive behaviour, resulting in predominantly advanced stage of disease at diagnosis. Response to available therapies is still disappointing. Aim of the present review is to illustrate the diverse new strategies under investigation, to improve the poor outcome of these patients.

RECENT FINDINGS

Applying molecular analysis in ATC is unravelling potentially actionable targets of therapy. If a mutation of BRAF V600E is found, a combination of Dabrafenib and Trametinib is the recommended treatment. In the presence of another druggable mutation, a specific targeted therapy may be proposed. In the absence of druggable mutations, immunotherapy is an alternative approach, especially in case of significant PD-L1 expression.

SUMMARY

The molecular profiling of tumour samples is elucidating the genetic alterations involved in ATC development, and new preclinical models are under study to define innovative approaches for individualized treatment of such patients. Hopefully this approach could improve ATC prognosis.

Using CRISPR/Cas9 to Edit a Thyroid Cancer Cell Line

Thyroid cancer is the most prevalent endocrine malignancy, comprising multiple types of cancer, with distinct clinical-pathological characteristics. The oncogenesis of thyroid cancer is related to genetic alterations in MAPK signaling that induce proliferation and modulate noncoding genes, such as microRNAs and long noncoding RNAs. In this context, CRISPR/Cas9 emerges as a potential tool to modify gene sequence and modulate gene expression in thyroid cancer cell lines. In this chapter, we explore some of the current studies in which researchers have applied CRISPR/Cas9 in vitro to investigate thyroid cancer biology (Fig. 5.1).

Neoadjuvant famitinib and camrelizumab, a new combined therapy allowing surgical resection of the primary site for anaplastic thyroid carcinoma

BACKGROUND

Anaplastic thyroid cancer (ATC) is considered the most lethal thyroid cancer, with an overall 5-year survival rate below 10%. The FDA approved a BRAF/MEK inhibitor combination for the treatment of patients with BRAF-mutated ATC. However, effective therapeutic options for patients with wild-type BRAF are lacking.

CASE

In our phase II study, patients having advanced/metastatic solid ATCs were treated with famitinib and camrelizumab, a combination therapy involving a multi-targeted kinase inhibitor and an anti-PD-1 antibody. We report a case of a patient with locally advanced unresectable ATC who underwent this combination therapy, allowing us to perform complete surgical resection followed by post-operative radiation therapy.

CONCLISION

To the best of our knowledge, this is the first report describing the use of famitinib and camrelizumab as a neoadjuvant treatment for ATC with wild-type BRAF. Clinical trial for a novel neoadjuvant approach for ATC are currently open for enrollment.

Rationale Efficacy and Safety Evidence of Lenvatinib and Pembrolizumab Association in Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma (ATC) are highly aggressive malignant tumors with poor overall prognosis despite multimodal therapy. As ATC are extremely rare, no randomized controlled study has been published for metastatic disease. Thyrosine kinase inhibitors, especially lenvatinib and immune checkpoint inhibitors such as pembrolizumab, are emerging drugs for ATC. Few studies have reported the efficacity of pembrolizumab and lenvatinib association, resulting in its frequent off-label use. In this review, we discuss rationale efficacy and safety evidence for the association of lenvatinib and pembrolizumab in ATC. First, we discuss preclinical rationale for pembrolizumab monotherapy, lenvatinib monotherapy and synergistic action of pembrolizumab and lenvatinib in the metastatic setting. We also discuss clinical evidence for immunotherapy and pembrolizumab in ATC through the analysis of studies evaluating immunotherapy, lenvatinib and pembrolizumab lenvatinib association in ATC. In addition, we discuss the safety of this association and potential predictive biomarkers of efficiency.

Towards an era of precise diagnosis and treatment: Role of novel molecular modification-based imaging and therapy for dedifferentiated thyroid cancer

Dedifferentiated thyroid cancer is the major cause of mortality in thyroid cancer and is difficult to treat. Hence, the essential molecular mechanisms involved in dedifferentiation should be thoroughly investigated. Several studies have explored the biomolecular modifications of dedifferentiated thyroid cancer such as DNA methylation, protein phosphorylation, acetylation, ubiquitination, and glycosylation and the new targets for radiological imaging and therapy in recent years. Novel radionuclide tracers and drugs have shown attractive potential in the early diagnosis and treatment of dedifferentiated thyroid cancer. We summarized the updated molecular mechanisms of dedifferentiation combined with early detection by molecular modification-based imaging to provide more accurate diagnosis and novel therapeutics in the management of dedifferentiated thyroid cancer.

Identification of immune-related ferroptosis prognostic marker and in-depth bioinformatics exploration of multi-omics mechanisms in thyroid cancer

Background: Factors such as variations in thyroid carcinoma (THCA) gene characteristics could influence the clinical outcome. Ferroptosis and immunity have been verified to play an essential role in various cancers, and could affect the cancer patients’ prognosis. However, their relationship to the progression and prognosis of many types of THCA remains unclear.

Methods: First, we extracted prognosis-related immune-related genes and ferroptosis-related genes from 2 databases for co-expression analysis to obtain prognosis-related differentially expressed immune-related ferroptosis genes (PR-DE-IRFeGs), and screened BID and CDKN2A for building a prognostic model. Subsequently, multiple validation methods were used to test the model’s performance and compare its performance with other 4 external models. Then, we explored the mechanism of immunity and ferroptosis in the occurrence, development and prognosis of THCA from the perspectives of anti-tumor immunity, CDKN2A-related competitive endogenous RNA regulatory, copy number variations and high frequency gene mutation. Finally, we evaluated this model’s clinical practice value.

Results: BID and CDKN2A were identified as prognostic risk and protective factors, respectively. External data and qRT-PCR experiment also validated their differential expression. The model’s excellent performance has been repeatedly verified and outperformed other models. Risk scores were significantly associated with most immune cells/functions. Risk score/2 PR-DE-IRFeGs expression was strongly associated with BRAF/NRAS/HRAS mutation. Single copy number deletion of CDKN2A is associated with upregulation of CDKN2A expression and worse prognosis. The predicted regulatory network consisting of CYTOR, hsa-miRNA-873-5p and CDKN2A was shown to significantly affect prognosis. The model and corresponding nomogram have been shown to have excellent clinical practice value.

Conclusion: The model can effectively predict the THCA patients’ prognosis and guide clinical treatment. Ferroptosis and immunity may be involved in the THCA’s progression through antitumor immunity and BRAF/NRAS/HRAS mutation. CYTOR-hsa-miRNA-873-5p-CDKN2A regulatory networks and single copy number deletion of CDKN2A may also affect THCA′ progression and prognosis.

American Head and Neck Society Endocrine Surgery Section and International Thyroid Oncology Group consensus statement on mutational testing in thyroid cancer: Defining advanced thyroid cancer and its targeted treatment

BACKGROUND

The development of systemic treatment options leveraging the molecular landscape of advanced thyroid cancer is a burgeoning field. This is a multidisciplinary evidence-based statement on the definition of advanced thyroid cancer and its targeted systemic treatment.

METHODS

An expert panel was assembled, a literature review was conducted, and best practice statements were developed. The modified Delphi method was applied to assess the degree of consensus for the statements developed by the author panel.

RESULTS

A review of the current understanding of thyroid oncogenesis at a molecular level is presented and characteristics of advanced thyroid cancer are defined. Twenty statements in topics including the multidisciplinary management, molecular evaluation, and targeted systemic treatment of advanced thyroid cancer are provided.

CONCLUSIONS

With the growth in targeted treatment options for thyroid cancer, a consensus definition of advanced disease and statements regarding the utility of molecular testing and available targeted systemic therapy is warranted.

Metastatic medullary thyroid carcinoma: a new way forward

Medullary thyroid carcinoma (MTC) is a rare malignancy comprising 1-2% of all thyroid cancers in the United States. Approximately 20% of cases are familial, secondary to a germline RET mutation, while the remaining 80% are sporadic and also harbour a somatic RET mutation in more than half of all cases. Up to 15-20% of patients will present with distant metastatic disease, and retrospective series report a 10-year survival of 10-40% from time of first metastasis. Historically, systemic therapies for metastatic MTC have been limited, and cytotoxic chemotherapy has demonstrated poor objective response rates. However, in the last decade, targeted therapies, particularly multitargeted tyrosine kinase inhibitors (TKIs), have demonstrated prolonged progression-free survival in advanced and progressive MTC. Both cabozantinib and vandetanib have been approved as first-line treatment options in many countries; nevertheless, their use is limited by high toxicity rates and dose reductions are often necessary. New generation TKIs, such as selpercatinib or pralsetinib, that exhibit selective activity against RET, have recently been approved as a second-line treatment option, and they exhibit a more favourable side-effect profile. Peptide receptor radionuclide therapy or immune checkpoint inhibitors may also constitute potential therapeutic options in specific clinical settings. In this review, we aim to present all current therapeutic options available for patients with progressive MTC, as well as new or as yet experimental treatments.

Combination Strategies Involving Immune Checkpoint Inhibitors and Tyrosine Kinase or BRAF Inhibitors in Aggressive Thyroid Cancer

Thyroid cancer is the most common (~90%) type of endocrine-system tumor, accounting for 70% of the deaths from endocrine cancers. In the last years, the high-throughput genomics has been able to identify pathways/molecular targets involved in survival and tumor progression. Targeted therapy and immunotherapy individually have many limitations. Regarding the first one, although it greatly reduces the size of the cancer, clinical responses are generally transient and often lead to cancer relapse after initial treatment. For the second one, although it induces longer-lasting responses in cancer patients than targeted therapy, its response rate is lower. The individual limitations of these two different types of therapies can be overcome by combining them. Here, we discuss MAPK pathway inhibitors, i.e., BRAF and MEK inhibitors, combined with checkpoint inhibitors targeting PD-1, PD-L1, and CTLA-4. Several mutations make tumors resistant to treatments. Therefore, more studies are needed to investigate the patient's individual tumor mutation burden in order to overcome the problem of resistance to therapy and to develop new combination therapies.

Anaplastic Thyroid Carcinoma: An Update

Anaplastic thyroid carcinoma (ATC) is a rare and undifferentiated form of thyroid cancer. Its prognosis is poor: the median overall survival (OS) of patients varies from 4 to 10 months after diagnosis. However, a doubling of the OS time may be possible owing to a more systematic use of molecular tests for targeted therapies and integration of fast-track dedicated care pathways for these patients in tertiary centers. The diagnostic confirmation, if needed, requires an urgent biopsy reread by an expert pathologist with additional immunohistochemical and molecular analyses. Therapeutic management, defined in multidisciplinary meetings, respecting the patient's choice, must start within days following diagnosis. For localized disease diagnosed after primary surgical treatment, adjuvant chemo-radiotherapy is recommended. In the event of locally advanced or metastatic disease, the prognosis is very poor. Treatment should then involve chemotherapy or targeted therapy and decompressive cervical radiotherapy. Here we will review current knowledge on ATC and provide perspectives to improve the management of this deadly disease.

Immunotherapy in anaplastic thyroid cancer: Case series

Unresectable anaplastic thyroid cancer (ATC) has a poor prognosis. Chemotherapy and radiotherapy have limited effects on it. Here, we present four cases who underwent immunotherapy for ATC. The patients were aged between 58 and 70 years. Two male patients with pulmonary metastases received pembrolizumab and lenvatinib. However, they died of septic shock and respiratory failure in 2.7 and 1 months, respectively, after the initiation of combination therapy. Another male patient with stage IVB disease was treated with spartalizumab. The tumor remained stable after surgical debulking but slightly progressed after 23 months. He survived for 45.5 months after spartalizumab initiation. A female patient with BRAF-mutant ATC and lung metastases was treated with a combination of pembrolizumab and lenvatinib, which was complicated with grade 4 transaminitis. The patient subsequently received dabrafenib (a BRAF inhibitor) and trametinib (a MEK inhibitor) treatment, which was continued for 10.2 months with a best response of partial remission. She died 18 months after the initial diagnosis (11.4 months after treatment with dabrafenib and trametinib). In conclusion, the treatment responses of immunotherapy, either alone or in combination with other therapies, were highly variable in patients with ATC and should be carefully monitored along with the side effects.

A New Way Out of the Predicament of Anaplastic Thyroid Carcinoma From Existing Data Analysis

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is an endocrine tumor with a low incidence but a very poor prognosis. The vast majority of patients have a survival time of only three to six months, but a few survive for two years or more. In recent years, there have been major breakthroughs in targeted and immunotherapy in the field of oncology therapy. Although the preliminary study for ATC showed a promising prospect, more clinical trials are needed. It is the best approach to explore the measures that can improve survival time of ATC from the available clinical data, especially those with long survival.

METHODS

We report on an 82-year-old ATC patient who survived for 3 years and systematically review the clinical characteristics of 45 ATC patients with complete data from the two largest centers in northwest China. In particular, factors related to long-term survival were analyzed and summarized.

RESULTS

Three years prior, an 82-year-old woman was diagnosed with ATC by core needle biopsy following a physical examination. The thyroid tumor was resected within one month, and then the patient was treated with radiotherapy. The patient was still healthy after three years of follow-up. Analysis of prognostic factors for the 45 reviewed patients showed that those undergoing radical surgery (median overall survival (OS) = 472 days, p = 0.0261) and radiotherapy (median OS = 220 days, p = 0.0136) had better outcomes. In addition, patients younger than 65 years (median OS = 164.5 days, p = 0.0176) and with a lower tumor stage (IV A, median OS = 633.5 days, p = 0.0191) also had a better outcome.

CONCLUSION

ATC is a highly malignant tumor, but timely early diagnosis and standardized treatment with radical surgery and radiotherapy as the core can achieve good results. Some patients can achieve long-term survival.

Metabolic Reprogramming of Thyroid Cancer Cells and Crosstalk in Their Microenvironment

Metabolism differs significantly between tumor and normal cells. Metabolic reprogramming in cancer cells and metabolic interplay in the tumor microenvironment (TME) are important for tumor formation and progression. Tumor cells show changes in both catabolism and anabolism. Altered aerobic glycolysis, known as the Warburg effect, is a well-recognized characteristic of tumor cell energy metabolism. Compared with normal cells, tumor cells consume more glucose and glutamine. The enhanced anabolism in tumor cells includes de novo lipid synthesis as well as protein and nucleic acid synthesis. Although these forms of energy supply are uneconomical, they are required for the functioning of cancer cells, including those in thyroid cancer (TC). Increasing attention has recently focused on alterations of the TME. Understanding the metabolic changes governing the intricate relationship between TC cells and the TME may provide novel ideas for the treatment of TC.

The Efficacy and Safety of Anlotinib in Neoadjuvant Treatment of Locally Advanced Thyroid Cancer: A Single-Arm Phase II Clinical Trial

Background: Surgery is the primary treatment for locally advanced thyroid cancer. For some cases, R0/R1 resection could not be achieved at initial diagnosis and neoadjuvant treatment would be an option. Anlotinib is a multitarget tyrosine kinase inhibitor, which demonstrated antitumor activity in radioiodine-refractory differentiated thyroid cancer and medullary thyroid cancer. We aimed to evaluate the efficacy and safety of anlotinib in locally advanced thyroid cancer in the neoadjuvant setting. Methods: This single-arm phase II study investigated the efficacy and safety of anlotinib (12 mg orally daily, 2 weeks on/1 week off) for 2-6 cycles in patients with locally advanced thyroid cancer in the neoadjuvant setting. The key eligibility criteria included age 14-80 years old; locally advanced thyroid cancer that would benefit from surgery, and at least one measurable lesion. Operable patients received surgery after neoadjuvant treatment. The primary endpoint was objective response rate (ORR). Results: A total of 13 patients were enrolled and received an average of 3.5 cycles of anlotinib treatment. The ORR of anlotinib was 76.9% (95% confidence interval: 46.2-95.0%). The R0/R1 resection rate in the intent-to-treat population was 61.5% and in the per-protocol population was 72.7%. The median time to response was 61.5 days, and the disease control rate at 18 weeks was 92.3%. No patients had blood transfusion or tracheotomy. Most adverse events (AEs) were grade 1 or 2 and tended to discontinue when neoadjuvant treatment ceased. Common AEs of all grades were hypertension (76.9%), hypertriglyceridemia (69.2%), proteinuria (53.8%), thyrotropin increase (53.8%), cholesterol elevation (53.8%), and hand-foot syndrome (38.5%). Conclusions: Anlotinib demonstrated antitumor activity in the neoadjuvant treatment and the majority of patients achieved R0/R1 resection. AEs were consistent with the known anlotinib AE profile. These results suggest that anlotinib neoadjuvant treatment represents a new option for locally advanced thyroid cancer. Clinical Trial Registration Number: NCT04309136.

Therapeutic Effect of Combined Dabrafenib and Trametinib Treatment of BRAF V600E-Mutated Primary Squamous Cell Carcinoma of the Thyroid: A Case Report

INTRODUCTION

Primary squamous cell carcinoma (PSCC) of the thyroid is an exceptionally rare malignancy accounting for <1% of all primary thyroid cancers. Therapy is multimodal including surgery, radiotherapy, and chemotherapy but with no consensus for management and therapy. Here, we describe a case of a male patient who presented with a BRAF V600E-mutated PSCC of the thyroid gland showing response to combined dabrafenib and trametinib therapy over a period of >12 months.

CASE PRESENTATION

A 78-year-old male patient presented with a 3-week history of dysphonia and dyspnoea. Laryngoscopy revealed a mechanical obstruction by a right-sided, subglottical mass, which on cervical ultrasound was highly suggestive of anaplastic thyroid carcinoma. Additional workup including esophagogastroduodenoscopy showed compression of the oesophagus but no oesophageal infiltration by the tumour. Immunohistochemistry displayed CK19-positive cells indicating epithelial origin of the tumour. CK5/6 and P40 immunohistochemistry confirmed the morphological impression of squamous cell differentiation while staining with thyroid markers TTF-1 and TPO was negative and PAX8 showed a nuclear positive signal. Based on immunohistopathology, presence of TP53 and BRAF V600E mutations, and exclusion of metastatic squamous cell carcinoma of other origin, the diagnosis of a PSCC of the thyroid was established. As an individualized treatment concept, we decided to advocate combined BRAF V600E targeting by the multikinase inhibitors dabrafenib and trametinib. This led to drastic improvement in patient's quality of life without severe side effects over a period of >12 months.

CONCLUSION

In this case, molecular diagnosis allowed a highly individualized treatment concept with combined dabrafenib and trametinib therapy.

[Molecular genotyping in refractory thyroid cancers in 2021: When, how and why? A review from the TUTHYREF network]

Refractory thyroid cancers include radio-iodine-refractory cancers, metastatic or locally advanced unresectable medullary and anaplastic thyroid cancers. Their management has been based for several years on the use of multi-target kinase inhibitors, with anti-angiogenic action, with the exception of anaplastic cancers usually treated with chemo- and radiotherapy. The situation has recently evolved due to the availability of molecular genotyping techniques allowing the discovery of rare but targetable molecular abnormalities. New treatment options have become available, more effective and less toxic than the previously available multi-target kinase inhibitors. The management of refractory thyroid cancers is therefore becoming more complex both at a diagnosis level with the need to know when, how and why to look for these molecular abnormalities but also at a therapeutic level, innovative treatments being hardly accessible. The cost of molecular analyzes and the access to treatments need also to be homogenized because disparities could lead to inequality of care at a national or international level. Finally, the strategy of identifying molecular alterations and treating these rare tumors reinforces the importance of a discussion in a multidisciplinary consultation meeting.

Anaplastic Thyroid Cancer Successfully Treated With Radiation and Immunotherapy: A Case Report

Objective

Anaplastic thyroid cancer (ATC) is a rare thyroid cancer subtype with a devastating prognosis. Novel treatment strategies are under investigation to improve the survival of patients with ATC.

Methods

We present a case of recurrent ATC treated with a combination of radiation therapy (RT) and pembrolizumab, a programmed death-1 inhibitor, with a durable complete response.

Results

A 63-year-old woman underwent total thyroidectomy and left neck lymph node dissection and was diagnosed with papillary carcinoma in December, 2017. She received radioiodine in April, 2018. However, a left neck mass was noted in April, 2018 with biopsy demonstrating ATC with 95% positivity for programmed death-ligand 1 immunostaining. Positron emission tomography showed fluorodeoxyglucose uptake in the left thyroid bed and multiple lymph nodes in the left retropharyngeal, left neck, and right upper paratracheal areas. Hypofractionated RT for the recurrent areas was initiated in August,2018, and concomitant pembrolizumab was given 2 days after RT. A total of 10 cycles of pembrolizumab (2 mg/kg) were given every 3 weeks. The computed tomography scan after completion of RT and 3 cycles of pembrolizumab showed shrinkage of the neck lymph nodes. The serial follow-up computed tomography scans showed further shrinkage of the lymph nodes, and there was no recurrence of ATC as of October, 2020.

Conclusion

We describe an ATC case successfully treated with a combination of RT and pembrolizumab with a durable response of 26 months and acceptable toxicities. This result warrants further investigation of this combination regimen in the treatment of ATC.

Surgical Considerations in Thyroid Cancer: What the Radiologist Needs to Know

Management of thyroid cancer requires a multidisciplinary approach including head and neck/endocrine surgeons, endocrinologists, oncologists, and radiologists. The radiographic evaluation of thyroid cancer is critical for complete and precise staging and affects the surgical approach to address these cancers. The purpose of this article is to briefly review the common thyroid cancer pathologies and surgical considerations in thyroid cancer, focusing on the extent of surgery and the influence of preoperative imaging on surgical decision-making. This article assumes that a diagnosis of thyroid cancer has been made and does not discuss the workup or surveillance of thyroid nodules.

Targeting the Highly Expressed microRNA miR-146b with CRISPR/Cas9n Gene Editing System in Thyroid Cancer

Thyroid cancer is the most common endocrine malignancy, and the characterization of the genetic alterations in coding-genes that drive thyroid cancer are well consolidated in MAPK signaling. In the context of non-coding RNAs, microRNAs (miRNAs) are small non-coding RNAs that, when deregulated, cooperate to promote tumorigenesis by targeting mRNAs, many of which are proto-oncogenes and tumor suppressors. In thyroid cancer, miR-146b-5p is the most overexpressed miRNA associated with tumor aggressiveness and progression, while the antisense blocking of miR-146b-5p results in anti-tumoral effect. Therefore, inactivating miR-146b has been considered as a promising strategy in thyroid cancer therapy. Here, we applied the CRISPR/Cas9n editing system to target the MIR146B gene in an aggressive anaplastic thyroid cancer (ATC) cell line. For that, we designed two single-guide RNAs cloned into plasmids to direct Cas9 nickase (Cas9n) to the genomic region of the pre-mir-146b structure to target miR-146b-5p and miR-146b-3p sequences. In this plasmidial strategy, we cotransfected pSp-Cas9n-miR-146b-GuideA-puromycin and pSp-Cas9n-miR-146b-GuideB-GFP plasmids in KTC2 cells and selected the puromycin resistant + GFP positive clones (KTC2-Cl). As a result, we observed that the ATC cell line KTC2-Cl1 showed a 60% decrease in the expression of miR-146b-5p compared to the control, also showing reduced cell viability, migration, colony formation, and blockage of tumor development in immunocompromised mice. The analysis of the MIR146B edited sequence shows a 5 nt deletion in the miR-146b-5p region and a 1 nt deletion in the miR-146b-3p region in KTC2-Cl1. Thus, we developed an effective CRISPR/Cas9n system to edit the MIR146B miRNA gene and reduce miR-146b-5p expression which constitutes a potential molecular tool for the investigation of miRNAs function in thyroid cancer.

Poorly Differentiated and Anaplastic Thyroid Cancer: Insights into Genomics, Microenvironment and New Drugs

Simple Summary

In the last decades, many researchers produced promising data concerning genetics and tumor microenvironment of poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC). They are trying to tear the veil covering these orphan cancers, suggesting new therapeutic weapons as single or combined therapies.

Abstract

PDTC and ATC present median overall survival of 6 years and 6 months, respectively. In spite of their rarity, patients with PDTC and ATC represent a significant clinical problem, because of their poor survival and the substantial inefficacy of classical therapies. We reviewed the newest findings about genetic features of PDTC and ATC, from mutations occurring in DNA to alterations in RNA. Therefore, we describe their tumor microenvironments (both immune and not-immune) and the interactions between tumor and neighboring cells. Finally, we recapitulate how this upcoming evidence are changing the treatment of PDTC and ATC.