Clinical Outcome and Toxicity in the Treatment of Anaplastic Thyroid Cancer in Elderly Patients

Background: The present study aims to evaluate the outcomes and toxicity of elderly anaplastic thyroid cancer (ATC) patients receiving (chemo)radiotherapy, as well as to identify prognostic factors. Patients and methods: A systematic review using the MEDLINE/PubMed and Cochrane databases was performed. Individual data from all eligible studies were extracted, and a pooled analysis (n = 186) was conducted to examine patient characteristics and treatment. All consecutive ATC patients (≥65 years) treated between 2009 and 2019 at our institution were evaluated for outcomes concerning progression-free survival (PFS), overall survival (OS) probabilities and treatment-related toxicity. Results: The systematic review and pooled analysis identified age as a prognostic factor. The median OS of our patient cohort (n = 26) was three months (range = 0–125). The 6-, 12- and 24-month survival rates were 35%, 22% and 11%, respectively. In the univariate analysis, a Karnofsky performance status of >70%, the Union for International Cancer Control Tumor–Node–Metastasis classification, multimodal therapy and an EQD2 of >49 Gy were correlated with longer OS and PFS. The acute grade 3 toxicity of dysphagia, dyspnea, dermatitis, mucositis and dysphonia was found in 23%, 15%, 12%, 12% and 8% of patients. Conclusion: Age appears to be a prognostic factor in ATC. Elderly ATC patients can tolerate multimodal treatment and achieve a promising outcome. Prospective studies need to confirm our findings.

Biological implications of PTEN upregulation and altered sodium/iodide symporter intracellular distribution in resveratrol-suppressed anaplastic thyroid cancer cells

Objective: Anaplastic thyroid cancer/ATC is a highly aggressive malignancy with extremely poor prognosis. Resveratrol/Res promotes re-differentiation of cancer cells and exerts inhibitory effects on ATC cells. Sodium/iodide symporter/NIS and phosphate and tension homology deleted on chromsome ten/PTEN levels are positively correlated with the grade of thyroid cancer differentiation, while the impact of Res on them remain unknown.

Materials and Methods: The patterns of NIS and PTEN expression and intracellular distribution in THJ-16T and THJ-21T ATC and Nthy-ori 3-1 normal thyroid cells and their relevance with Res-caused ATC suppression were investigated via multiple experimental methods. E-cadherin was cited as a re-differentiation biomarker of ATC cells.

Results: MTT and EdU cell proliferation assays showed distinct growth suppression in ATC cells after Res treatment. TUNEL staining revealed extensive apoptosis of Res-treated THJ-16T and THJ-21T rather than Nthy-ori 3-1 cells. Western blotting, immunocytochemical/ICC and double-labeled immunofluorescent/IF staining showed increased PTEN levels accompanied with distinct NIS and PTEN nuclear co-translocation in Res-treated THJ-16T and THJ-21T cells. E-cadherin but not NIS appeared on the outer membrane.

Conclusion: PTEN upregulation and the concurrent NIS and PTEN nuclear translocation in Res-suppressed ATC cells may indicate the better therapeutic outcome and would be a group of beneficial prognostic factors of ATCs.

Melatonin synergizes BRAF-targeting agent dabrafenib for the treatment of anaplastic thyroid cancer by inhibiting AKT/hTERT signalling

As a selective inhibitor of BRAF kinase, dabrafenib has shown potent anti‐tumour activities in patients with BRAFV600E mutant anaplastic thyroid cancer. However, the resistance of thyroid cancer cells to dabrafenib limited its therapeutic effect. The effects of melatonin and dabrafenib as monotherapy or in combination on the proliferation, cell cycle arrest, apoptosis, migration and invasion of anaplastic thyroid cancer cells were examined. The molecular mechanism involved in drug combinations was also revealed. Melatonin enhanced dabrafenib‐mediated inhibition of cell proliferation, migration and invasion, and promoted dabrafenib‐induced apoptosis and cell cycle arrest in anaplastic thyroid cancer cells. Molecular mechanistic studies further uncovered that melatonin synergized with dabrafenib to inhibit AKT and EMT signalling pathways. Furthermore, melatonin and dabrafenib synergistically inhibited the expression of hTERT, and the inhibition of cell viability and the induction of cell cycle arrest mediated by the combination of these two drugs were reversed by hTERT overexpression. Taken together, our results demonstrated that melatonin synergized the anti‐tumour effect of dabrafenib in human anaplastic thyroid cancer cells by inhibiting multiple signalling pathways, and provided new insights in exploring the potential therapeutic targets for the treatment of anaplastic thyroid cancer.

Synergistic anticancer activity of sorafenib, paclitaxel, and radiation therapy on anaplastic thyroid cancer in vitro and in vivo

BACKGROUND

This study aimed to investigate the antitumor activity of paclitaxel with radiation and sorafenib in anaplastic thyroid cancer (ATC) cells in vitro and in vivo.

METHODS

The 8505C ATC cell line was exposed to radiation, sorafenib, and paclitaxel each or in combination. The effects of combined treatment on the cell cycle and intracellular signaling pathways were assessed using flow cytometry and western blot analysis. An ATC cell line xenograft model was used to examine antitumor activity in vivo.

RESULTS

Radiation, paclitaxel plus sorafenib synergistically decreased cell viability in ATC cells and significantly increased apoptotic cell death. The combination of paclitaxel, sorafenib with radiation reduced the antiapoptotic factor in ATC. This combination therapy significantly reduced the tumor volume and increased survival in the ATC xenograft model.

CONCLUSIONS

These results suggest that the combination of radiation and paclitaxel plus sorafenib has significant anticancer activity in preclinical models.

Hypofractionated Radiotherapy for Anaplastic Thyroid Cancer: Systematic Review and Pooled Analysis

Simple Summary

Anaplastic thyroid carcinoma is an aggressive cancer subtype with a dismal prognosis. Multimodal treatment approaches consisting of surgical resection, radiation therapy (RT) and chemotherapy have resulted in longer overall survival and promising outcomes. Hypofractionated RT is an alternative to conventional RT regimens. In this study, we aim to evaluate the outcome of hypofractionated regimens, perform a systematic review concerning hypofractionated RT and pooled analysis of this treatment modality. Hypofractionated RT appears to be non-inferior compared to conventional RT concerning OS after propensity score matching. In addition, radiation dose escalation correlated with a longer OS. In conclusion, hypofractionated RT is effective with manageable toxicity and could be an integral part in multimodal treatment.

Abstract

Anaplastic thyroid carcinoma (ATC) is associated with a poor prognosis due to aggressive tumor growth and high treatment resistance. Hypofractionated treatment concepts may be more effective and less time consuming compared to normofractionated radiotherapy (RT). In this retrospective study, we aim to evaluate the outcome of hypofractionated regimens and perform a systematic review concerning hypofractionated RT and pooled analysis of this treatment modality. A systematic review using the MEDLINE/Pubmed and Cochrane databases was performed. Data from all eligible studies were extracted, and a pooled analysis of literature and our cohort (n = 60) was carried out to examine patient characteristics, toxicity, and outcomes of patients with ATC. As a result, median overall survival (OS) of the single center cohort was four (range 1–12) months. Survival rates at one, three, and six months were 82%, 55%, and 36%, respectively. In univariate analyses, multimodal treatment (p = 0.006) and gender (p = 0.04) were correlated with an improved OS. Six studies with a total number of 152 patients undergoing hypofractionated RT treatment were analyzed. The pooled analysis included four patient cohorts with 60 patients and showed median OS of 5.3 (range: 1–24) months. Multimodal treatment (p < 0.001) and a cumulative radiation dose ≥50 Gy in equivalent dose in 2 Gy fractions (EQD2) (p = 0.014) correlated with an improved OS. On multivariate analysis, multimodal treatment (p = 0.003, hazard ratio (HR): 0.636, 95% confidence interval (CI): 0.469–0.861) was an independent predictor for longer OS. After propensity score matching (PSM), hypofractionated RT appears to be non-inferior compared to normofractionated RT concerning OS. In conclusion, hypofractionated RT is effective with manageable toxicity. A dose escalation with ≥50 Gy (EQD2) correlated with a longer OS. Hypofractionated RT could be an integral part in multimodal treatment with a promising outcome.

Acquired Secondary RAS Mutation in BRAFV600E-Mutated Thyroid Cancer Patients Treated with BRAF Inhibitors

Background: The BRAF^V600E mutation is the most common driver mutation in papillary thyroid cancer (PTC) and anaplastic thyroid cancer (ATC). This mutation is considered actionable and, for BRAF^V600E-mutated ATC, a BRAF inhibitor (dabrafenib) in combination with an MEK inhibitor (trametinib) is FDA approved. BRAF inhibitors have also shown efficacy in BRAF^V600E-mutated PTC. However, as with all targeted therapies, resistance to these drugs eventually develops. It is essential that we understand the mechanisms of resistance to the BRAF inhibitors in thyroid cancer to develop future strategies to effectively treat these patients and improve survival. Patients: Herein, we describe four patients with thyroid cancer treated with selective BRAF inhibitors, who developed a RAS mutation in addition to the BRAF^V600E mutation at progression. Results: Patients 1 and 3 acquired a KRAS^G12V mutation in the progressive tumor, patient 2 acquired a NRAS^Q61K mutation in a progressive lymph node, and patient 4 acquired NRAS^G13D mutation on liquid biopsy performed at the time of radiographic disease progression. Conclusion: Similar to the melanoma experience, the emergence of RAS mutations appears to act as a mechanism of resistance to BRAF inhibitors in thyroid cancers.

Foundation One Genomic Interrogation of Thyroid Cancers in Patients With Metastatic Disease Requiring Systemic Therapy

CONTEXT

Clinical applications of genomic assessment of thyroid cancers are rapidly evolving.

OBJECTIVES, DESIGN, AND SETTING

We studied tumor samples from patients with imminently threatening and rare thyroid cancers to identify genomic alterations that might correlate with outcomes and/or be productively therapeutically targetable.

PATIENT CONTEXT

Progressive and metastatic, and/or rare, thyroid cancers were studied, 2012 to 2016, at Mayo Clinic sites.

INTERVENTION

The intervention was Foundation One tumor interrogation.

MAIN OUTCOME MEASURES

Main outcome measures included genomic alterations, patient characteristics, and overall survival.

RESULTS

Samples from 55 patients were evaluated: 20 anaplastic thyroid cancers (ATCs) (36%), 25 radioactive iodine-refractory differentiated thyroid cancers (DTCs)/poorly differentiated thyroid cancers (PDTCs) (45%; 14 papillary thyroid cancer [PTCs], 6 PDTCs, 5 Hürthle cell cancers), 8 medullary thyroid cancers (MTCs) (15%), and 2 others (a spindle epithelial tumor with thymus-like differentiation, and a primary thyroid sarcoma). Overall, 72% of DTCs, 79% of ATCs, and 75% of MTCs were deemed to have potentially productively targetable alterations. The most commonly encountered mutation was of TERT promoter (56% of DTCs, 68% of ATCs)-but this is not presently targetable. Targetable BRAFV600E mutations were found in 40% of DTCs/PDTCs (83% of PTCs) and 32% of ATCs; of MTCs, 75% had targetable RET mutations, and 25% HRAS mutations. Of patient tumors with nonmutated BRAFV600E, 53% of DTC/PDTCs and 69% of ATCs had other potentially productively targetable mutations. Genomic alterations in our series of poor prognosis metastatic DTC/PDTCs also closely resembled those seen in ATC.

CONCLUSIONS

Whereas genomic interrogation of favorable prognosis thyroid cancer seems ill advised, potentially productively targetable mutations were demonstrated in the majority of tumors from patients with metastatic thyroid cancers requiring systemic therapy, suggesting a rationale for the selective application of this technology.

Tissue Factor-Targeted ImmunoPET Imaging and Radioimmunotherapy of Anaplastic Thyroid Cancer

Anaplastic thyroid cancer (ATC) is the most aggressive subtype of thyroid cancers with a dismal prognosis. It is aimed to explore a new biomarker and devise a marker-dependent theranostic pair for ATC. Flow cytometry is used to determine tissue factor (TF) expression in thyroid cancer cell lines. ALT-836, a TF-specific monoclonal antibody, is radiolabeled with 64Cu to develop 64Cu-NOTA-ALT-836. The diagnostic utility is assessed by immuno-positron emission tomography (immunoPET) imaging in ATC models. To facilitate total surgical removal of orthotopic ATCs, a near-infrared fluorescent imaging probe IRDye 800CW-ALT-836 is designed. As the therapeutic component, 131I-ALT-836 is further developed and the radioimmunotherapy (RIT) efficacy of this agent is interrogated in orthotopic ATC models. The results demonstrate that TF is highly expressed on the ATC cell line THJ-16T. 64Cu-NOTA-ALT-836 immunoPET imaging clearly delineates both subcutaneous and orthotopic ATCs, with a peak tumor uptake of 19.93 ± 2.17% ID per g (n = 3) and 37.20 ± 1.71% ID per g (n = 3), respectively. Fluorescent imaging with IRDye 800CW-ALT-836 facilitates the total resection of orthotopic ATCs. Moreover, 131I-ALT-836 RIT prolongs the survival of ATC-bearing mice. Taken together, TF is a promising marker for ATC and successive use of 64Cu-NOTA-ALT-836 and 131I-ALT-836 can realize precise management of ATC.

Diagnostic and prognostic value of preoperative systemic inflammatory markers in anaplastic thyroid cancer

BACKGROUND

Easily accessible, generalized, and inexpensive methods are expected to differentiate anaplastic thyroid carcinoma (ATC) from advanced differentiated thyroid cancer (aDTC). We aimed to explore potential diagnostic and prognostic value of systematic inflammatory markers (SIMs) in ATC and aDTC.

METHODS

About 22 ATC, 101 aDTC, and 100 matched early DTC patients were analyzed retrospectively. SIMs included the comprehensive index, neutrophil-monocyte-platelet-to-lymphocyte ratio (NMPLR) and the previously reported ones. Receiver operating characteristic, Kaplan-Meier, and COX regression analyses were mainly conducted.

RESULTS

NMPLR exhibited the highest area under the curve value 0.806 (P < .0001) to diagnose ATC from aDTC. NMPLR was identified as an independent risk factor for overall survival (OS) (hazard ratio [HR]: 47.821, 95% confidence interval [CI], 2.863-798.765, P = .007) in ATC, as well as for OS (HR: 7.360, 95% CI, 1.620-33.430, P = .010) and recurrence-free survival (HR: 4.172, 95% CI, 1.139-15.286, P = .031) in aDTC. Taken both refractory types (ATC and aDTC) together, NMPLR could independently predict OS (HR: 6.470; 95% CI, 2.134-19.616; P = .001).

CONCLUSION

NMPLR is a generalized index. It showed excellent potential in differential diagnosis and survival prediction in refractory thyroid cancer. However, it needs to be validated in larger cohort and clinical practice.

Anaplastic thyroid cancer: How far can we go?

Globally, thyroid cancer accounts for 2 % of all cancer diagnoses, and can be classified as well-differentiated or undifferentiated. Currently, differentiated thyroid carcinomas have good prognoses, and can be treated with a combination of therapies, including surgical thyroidectomy, radioactive iodine therapy and hormone-based therapy. On the other hand, anaplastic thyroid carcinoma, a subtype of undifferentiated thyroid carcinoma characterized by the loss of thyroid-like phenotype and function, does not respond to either radioactive iodine or hormone therapies. In most cases, anaplastic thyroid carcinomas are diagnosed in later stages of the disease, deeming them inoperable, and showing poor response rates to systemic chemotherapy. Recently, treatment courses using multiple-target agents are being explored and clinical trials have shown very promising results, such as overall survival rates, progression-free survival and tumor shrinkage. This review is focused on thyroid carcinomas, with particular focus on anaplastic thyroid carcinoma, exploring its undifferentiated nature. Special interest will be given to the treatment approaches currently available and respective obstacles or drawbacks. Our purpose is to contribute to understand why this malignancy presents low responsiveness to current treatments, while overviewing novel therapies and clinical trials.

Clinical Development of BRAF plus MEK Inhibitor Combinations

Genomic profiling shows that many solid tumors are characterized by specific driver aberrations, and this has expanded the therapeutic options for many patients. The mitogen-activated protein kinase (MAPK) pathway is a key cell signaling pathway involved in regulating cellular growth, proliferation, and survival. Driver mutations in the BRAF gene, a key player in the MAPK pathway, are described in multiple tumor types, including subsets of melanoma, non-small cell lung cancer (NSCLC), and anaplastic thyroid cancer (ATC), making BRAF a desirable target for inhibition. BRAF inhibitors have shown efficacy in several cancers; however, most patients eventually develop resistance. To delay or prevent resistance, combination therapy targeting BRAF and MEK, a downstream signaling target of BRAF in the MAPK pathway, was evaluated and demonstrated synergistic benefit. BRAF and MEK inhibitor combinations have been approved for use in various cancers by the US FDA. We review the clinical data for various BRAF plus MEK combination regimens in three cancer types with underlying BRAF driver mutations: melanoma, NSCLC, and ATC. We also discuss practical treatment considerations and management of selected combination therapy toxicities.

Synergy of GSK-J4 With Doxorubicin in KRAS-Mutant Anaplastic Thyroid Cancer

Background

Anaplastic thyroid cancer is the most aggressive thyroid cancer and has a poor prognosis. At present, there is no effective treatment for it.

Methods

Here, we used different concentrations of GSK-J4 or a combination of GSK-J4 and doxorubicin to treat human Cal-62, 8505C, and 8305C anaplastic thyroid cancer (ATC) cell lines. The in vitro experiments were performed using cell viability assays, cell cycle assays, annexin-V/PI binding assays, Transwell migration assays, and wound-healing assays. Tumor xenograft models were used to observe effects in vivo.

Results

The half maximal inhibitory concentration (IC50) of GSK-J4 in Cal-62 cells was 1.502 μM, and as the dose of GSK-J4 increased, more ATC cells were blocked in the G2-M and S stage. The combination of GSK-J4 and doxorubicin significantly increased the inhibitory effect on proliferation, especially in KRAS-mutant ATC cells in vivo (inhibition rate 38.0%) and in vitro (suppresses rate Fa value 0.624, CI value 0.673). The invasion and migration abilities of the KRAS-mutant cell line were inhibited at a low concentration (p < 0.05).

Conclusions

The combination of GSK-J4 with doxorubicin in KRAS-mutant ATC achieved tumor-suppressive effects at a low dose. The synergy of the combination of GSK-J4 and doxorubicin may make it an effective chemotherapy regimen for KRAS-mutant ATC.

Novel role of ASH1L histone methyltransferase in anaplastic thyroid carcinoma

Anaplastic thyroid cancer (ATC) is one of the most aggressive human malignancies, with an average life expectancy of ∼6 months from the time of diagnosis. The genetic and epigenetic changes that underlie this malignancy are incompletely understood. We found that ASH1-like histone lysine methyltransferase (ASH1L) is overexpressed in ATC relative to the much less aggressive and more common differentiated thyroid cancer. This increased expression was due at least in part to reduced levels of microRNA-200b-3p (miR-200b-3p), which represses ASH1L expression, in ATC. Genetic knockout of ASH1L protein expression in ATC cell lines decreased cell growth both in culture and in mouse xenografts. RNA-Seq analysis of ASH1L knockout versus WT ATC cell lines revealed that ASH1L is involved in the regulation of numerous cancer-related genes and gene sets. The pro-oncogenic long noncoding RNA colon cancer-associated transcript 1 (CCAT1) was one of the most highly (approximately 68-fold) down-regulated transcripts in ASH1L knockout cells. Therefore, we investigated CCAT1 as a potential mediator of the growth-inducing activity of ASH1L. Supporting this hypothesis, CCAT1 knockdown in ATC cells decreased their growth rate, and ChIP-Seq data indicated that CCAT1 is likely a direct target of ASH1L's histone methyltransferase activity. These results indicate that ASH1L contributes to the aggressiveness of ATC and suggest that ASH1L, along with its upstream regulator miR-200b-3p and its downstream mediator CCAT1, represents a potential therapeutic target in ATC.

Concurrent Anaplastic and Papillary Thyroid Carcinomas: A Case Report

Anaplastic thyroid cancer (ATC) is a rare, but extremely aggressive, form of cancer with a high mortality rate. Differentiated thyroid cancer (DTC), on the other hand, including papillary and follicular subtypes, are relatively common and typically follows a more indolent course. Cases have been reported in which ATC transforms from DTC, and where DTC and ATC exist simultaneously. Given the low incidence of such cases, they have not been well studied, and the optimal treatment regimen has yet to be determined. We present a case of a 77-year-old woman who was initially presented with papillary thyroid cancer (PTC) with focal ATC. Five months after undergoing total thyroidectomy, she returned with a new right sided neck mass. Fine needle aspiration (FNA) with biopsies of the mass and lymph node at one level revealed a smear pattern consistent with ATC. However, lymph node biopsy taken from a different level revealed a smear pattern consistent with PTC. Mutation analysis was performed and results were positive for metastatic BRAF V600- mutant ATC. The patient was then started on dabrafenib/trametinib chemotherapy. Seven months later, she was tolerating treatment well. These unique clinical features including the initial presentation and the relatively favorable survival, that is more than double that of the median survival rate for ATC, suggests that those with synchronous PTC and ATC may have a more indolent course with better prognosis than those with ATC alone. It is also possible that the relatively longer survival in our patient is due to the use of the BRAF inhibitor, dabrafenib and the MEK inhibitor, trametinib in this case with concurrent ATC and PTC. While patients with both PTC and ATC have been documented to have mutations in the BRAF V600 gene, the objective of this report is to present the relatively favorable outcomes when a therapeutic regimen is guided by mutation analysis. Future research into advanced treatment options including targeted therapy and/or immunotherapy for both DTC and ATC is needed. Somatic mutation testing may also be helpful to identify oncogenic kinase abnormalities that will inform therapeutic decision making.

A Novel Tyrosine Kinase Inhibitor Can Augment Radioactive Iodine Uptake Through Endogenous Sodium/Iodide Symporter Expression in Anaplastic Thyroid Cancer

Background: Radioactive iodine (RAI) therapy is an important strategy in the treatment of thyroid cancer. However, anaplastic thyroid cancer (ATC), a rare malignancy, exhibits severe dedifferentiation characteristics along with a lack of sodium iodide symporter (NIS) expression and function. Therefore, RAI therapy is ineffective and contributes toward poor prognosis of these patients. Recently, small-molecule tyrosine kinase inhibitors (TKIs) have been used to treat thyroid cancer patients for restoring NIS expression and function and RAI uptake capacity. However, most results reported thus far are associated with differentiated thyroid cancer. In this study, we identified a new TKI and investigated its effects on cell redifferentiation, NIS function, and RAI therapy in ATC. Methods: We identified a new TKI, "5-(5-{4H, 5H,6H-cyclopenta[b]thiophen-2-yl}-1,3,4-oxadiazol-2-yl)-1-methyl-1,2-dihydropyridin-2-one" (CTOM-DHP), using a high-throughput screening system. CTOM-DHP was exposed to 8505C ATC cells at different concentrations and time points. Concentrations of 12.5 and 25 μM and an incubation time of 72 hours were chosen as the conditions for subsequent NIS promoter assays and NIS mRNA and protein expression experiments. In addition, we examined factors related to iodide metabolism after CTOM-DHP treatment as well as the signaling pathways mediating the effects of CTOM-DHP on endogenous NIS expression. RAI uptake and ¹³¹I cytotoxicity effects caused by CTOM-DHP pretreatment were also evaluated in vitro and in vivo. Results: Promoter assays as well as mRNA and protein expression analyses confirmed that NIS expression was augmented by treatment of 8505C ATC cells with CTOM-DHP. Moreover, CTOM-DHP treatment robustly increased the expression of other thyroid-specific proteins and thyroid transcription factors related to iodide metabolism. Enhancement of NIS function was demonstrated by an increase in ¹²⁵I uptake and ¹³¹I cytotoxicity. Increased endogenous NIS expression was associated with the inhibition of PI3K/Akt and MAPK signaling pathways. In vivo results also demonstrated an increase in NIS promoter activity and RAI avidity in response to CTOM-DHP treatment. Furthermore, ¹³¹I-mediated therapeutic effects preferentially improved in a tumor xenograft mice model. Conclusions: CTOM-DHP, a new TKI identified in this study, enhances endogenous NIS expression and thereby is a promising compound for restoring RAI avidity in ATC.

Immunotherapy in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the worst human malignancies, with an associated median survival of only 5 months. It is resistant to conventional thyroid cancer therapies, including radioiodine and thyroid-stimulating hormone suppression. Cancer immunotherapy has emerged over the past few decades as a transformative approach to treating a wide variety of cancers. However, immunotherapy for ATC is still in the experimental stage. This review will cover several strategies of immunotherapy and discuss the possible application of these strategies in the treatment of ATC (such as targeted therapy for tumor-associated macrophages, cancer vaccines, adoptive immunotherapy, monoclonal antibodies and immune checkpoint blockade) with the hope of improving the prognosis of ATC in the future.

Global RNA Expression and DNA Methylation Patterns in Primary Anaplastic Thyroid Cancer

Anaplastic thyroid cancer (ATC) is one of the most malignant tumors, with a median survival of only a few months. The tumorigenic processes of this disease have not yet been completely unraveled. Here, we report an mRNA expression and DNA methylation analysis of fourteen primary ATCs. ATCs clustered separately from normal thyroid tissue in unsupervised analyses, both by RNA expression and by DNA methylation. In expression analysis, enrichment of cell-cycle-related genes as well as downregulation of genes related to thyroid function were seen. Furthermore, ATC displayed a global hypomethylation of the genome but with hypermethylation of CpG islands. Notably, several cancer-related genes displayed a correlation between RNA expression and DNA methylation status, including MTOR, NOTCH1, and MAGI1. Furthermore, TSHR and SLC26A7, encoding the thyroid-stimulating hormone receptor and an iodine receptor highly expressed in normal thyroid, respectively, displayed low expression as well as aberrant gene body DNA methylation. This study is the largest investigation of global DNA methylation in ATC to date. It shows that aberrant DNA methylation is common in ATC and likely contributes to tumorigenesis in this disease. Future explorations of novel treatments should take this into consideration.

Evaluation of the 8th Edition TNM Classification for Anaplastic Thyroid Carcinoma

Background: The tumor–node–metastasis (TNM) classification system to categorized anaplastic thyroid cancer (ATC) was revised. Methods: The revised system was evaluated using a large database of ATC patients. Results: A total of 757 patients were analyzed. The proportion and median overall survival values (OS: months) for each T category were T1 (n = 8, 1.1%, 12.5), T2 (n = 43, 5.7%, 10.9), T3a (n = 117, 15.5%, 5.7), T3b (n = 438, 57.9%, 3.9), and T4 (n = 151, 19.9%, 5.0). The OS of the N0 and N1 patients were 5.9 and 4.3, respectively (log-rank p < 0.01). Sixty-three (58.3%) patients migrated from stage IV A to IV B by revision based on the existence of nodal involvement and 422 patients (55.7%) were stratified into stage IV B, without a worsening of their OS (6.1), leaving 45 patients (5.9%) in stage IV A with fair OS (15.8). The hazard ratios for the survival of the patients of stage IV B compared to stage IV A increased from 1.1 to 2.1 by the revision. No change was made for stage IV C (n = 290, 38.8%, 2.8). Conclusion: The revised TNM system clearly indicated the prognoses of ATC patients by extracting rare patients with fair prognoses as having stage IV A disease and categorized many heterogeneous patients in stage IV B.

A Novel Multimodal Therapy for Anaplastic Thyroid Carcinoma: 125 I Seed Implantation Plus Apatinib After Surgery

Anaplastic thyroid cancer is known to be the most lethal malignancy among endocrine tumors for its extremely limited survival rate after diagnosis. As a result of this poor survival prognosis, multimodal therapy is currently under investigation to address this global concern. In this reported case, the ¹²⁵I seed implantation and vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor apatinib were co-applied to treat a 49-year-old woman with anaplastic thyroid cancer. After the patient began apatinib administration and underwent ¹²⁵I seed implantation twice, the tumor size shrank successfully. After a follow-up of 13 months since the initial diagnosis of anaplastic thyroid cancer, the patient survived with a stable disease pathology. In conclusion, this study supports ¹²⁵I seed implantation and apatinib as effective therapeutic alternatives for inoperable anaplastic thyroid cancer patients.

DURABLE RESPONSE IN A CASE OF METASTATIC ANAPLASTIC THYROID CANCER USING A COMBINATION OF TYROSINE KINASE INHIBITORS AND A CHECK POINT INHIBITOR

Anaplastic thyroid cancer (ATC) is a highly uncommon (less than 2% of thyroid malignancies) and aggressive type of cancer, with aggressive behavior and, therefore, exhibiting poor prognosis. ATC tumors are automatically labeled as stage IV disease regardless of standard criteria such as tumor burden or metastasis. ATC tumors require a diversified treatment approach that includes surgical resection, followed by a complete an aggressive combination of radiation and chemotherapy and/or palliative care. Despite best efforts, 1-year overall survival of patients is 20% to 40% with nearly universal mortality rate. Consequently, novel approaches (targeted therapy, immunotherapy) have been studied, alone or in combination, to improve the dire prognosis of these patients. BRAF V600E mutation is the most common genetic mutation found in ATC. We report the case of a 57-year-old man diagnosed with stage IVc (undifferentiated) ATC with hepatic and osseous metastases. The molecular analysis of the tumor revealed a V600E BRAF-mutation. The patient was treated with Dabrafenib and Trametinib, and achieved remission 5 weeks after starting the treatment. Subsequently, he had a thyroidectomy, and pembrolizumab was added to the two tyrosine kinase inhibitors. 9 months later he is still in remission. This case illustrates the importance of obtaining molecular information in anaplastic thyroid cancer and the urgent need of studies investigating the combination of tyrosine kinase inhibitors and check-point inhibitors in patients with V600E BRAF- mutations.

Survival With Lenvatinib for the Treatment of Progressive Anaplastic Thyroid Cancer: A Single-Center, Retrospective Analysis

Background: Survival rates for anaplastic thyroid cancer (ATC) have not improved in the past four decades; however, preliminary clinical data indicate that lenvatinib may provide efficacy benefits for patients with ATC. This real-world study aimed to define the potential role of lenvatinib in ATC by examining the impact of treatment administered alongside existing therapies. Methods: This was a retrospective, single-center analysis of Korean patients with confirmed ATC who received lenvatinib between October 2015 and February 2018. Eighteen patients were included (mean ± standard deviation age, 64.9 ± 11.1 years; 61.1% female). Six [33.3%] had resectable disease that progressed after a combination of surgery, radiotherapy, and chemotherapy, and 12 [66.7%] had unresectable disease that progressed after radiation treatment and chemotherapy. Study endpoints were overall survival (OS) and change in volume of the largest tumor assessed via imaging. Results: Median OS for the 18 lenvatinib-treated patients was 230 days (range 64-839 days). Survival rates at 6 months and 1 year were 61.1 and 22.2%, respectively. Three patients (16.7%) survived beyond 1 year; 15 patients died, of whom four (26.7%) had local disease and 11 (73.3%) had distant metastasis. Two patients (11.1%) had tumor volume increases of 9-10%. The other 16 patients (88.9%) had tumor volume reductions of 2-69%. Six patients (33.3%) had tumor volume reductions ≥50%. Conclusions: In patients with ATC who had progressed on prior therapy, addition of lenvatinib could improve survival duration and reduce tumor volume. Further studies of lenvatinib in ATC are warranted.

Lenvatinib vs. palliative therapy for stage IVC anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is an orphan disease with extremely poor prognosis. In particular, unresectable stage IVC ATC is extremely difficult to treat and is associated with a survival of only a few months, even when treated with irradiation and/or chemotherapy. In 2015, lenvatinib was approved for the treatment of ATC in Japan. The aim of the present study was to evaluate the efficacy of lenvatinib for stage IVC ATC. A total of 32 patients with pathologically confirmed stage IVC ATC who were treated at the Kanagawa Cancer Center between 2011 and 2018 were included in the present study, of whom 16 patients were treated with lenvatinib (L group). The remaining 16 patients received palliative therapy (P group), of whom 7 were treated with weekly paclitaxel, 2 received external radiation for tumor reduction 5 days per week until treatment completion, and 2 underwent tracheostomy to avoid the risk of asphyxiation. The survival curves of both groups were analyzed using the log-rank test. The median overall survival time of the L and P groups was 4.2 and 2.0 months, respectively. A significant survival benefit was observed in the L group compared with that in the P group (P=0.00298). A reduction in tumor size by ≥30% (clinical partial response) within 1 month after treatment was observed in 5 patients (31.3%) in the L group and in no patients in the P group. Therefore, lenvatinib treatment yielded a median survival benefit of ~2 months compared with palliative therapy in stage IVC ATC. However, although a reduction in tumor size by ≥30% was confirmed in 5 patients who received lenvatinib treatment, 2 of those patients succumbed to massive necrosis and bleeding. These results suggest that an appropriate lenvatinib dose reduction is necessary.

Integrated analysis of transcriptome data revealed MMP3 and MMP13 as critical genes in anaplastic thyroid cancer progression

To better understand the molecular mechanisms of anaplastic thyroid carcinoma (ATC), we aimed to identify the hub genes specifically involved in ATC by integrated bioinformatics analysis. In this study, using three Gene Expression Omnibus data sets with the same platform GPL570, we screened hub genes involved in ATC progression. In vitro experiments, such as western blot analysis, Transwell assays, and coimmunoprecipitation, was performed to verify our findings. By comparing three subtypes of thyroid cancer with normal tissue, we found ATC harbored more changed genes than well and poorly differentiated thyroid cancer. Using specifically differentially expressed genes between ATC and normal thyroid tissues to perform Gene ontology (GO) analysis, ATC showed enrichments of GO terms involved in lymphocyte migration and activation, collagen catabolic and metabolic process, thyroid hormone synthesis, and embolism. Using genes involved in extracellular matrix, coexpression network analysis and protein-protein interaction analysis were performed to identify matrix metalloproteinase 3 (MMP3) and MMP13 as two hub genes. Our experimental data indicated that both MMP3 and MMP13 were upregulated in ATC and knockdown of either of them could notably suppress ATC cell invasion and migration. Mechanistically, Gene Set Enrichment Analysis, coimmunoprecipitation, and rescue experiments revealed MMP3 and MMP13 not only interacted with each other, but also regulated each other through the janus kinase/signal transducer and activator of transcription 3 and mammalian target of rapamycin pathways. In conclusion, we identified a specific molecular mechanisms for the development of ATC by integrated analysis of transcriptome and in vitro experiments, which suggested that MMP3 and MMP13 might be developed as novel therapeutic targets for ATC.

Salutary Response to Targeted Therapy in Anaplastic Thyroid Cancer

Context. Anaplastic thyroid cancer (ATC) is an aggressive tumor with a median survival of 3 to 9 months, a 1-year survival of less than 10% and without definitive therapies. Recently, in BRAF V600E mutated ATCs, new targeted therapy using a combination of a BRAF inhibitor, dabrafenib (Dab), with a mitogen-activated extracellular protein kinase (MEK) inhibitor, trametinib (Tram), has shown significant promise. Case Description. We report a case of aggressive ATC with 5 sequence mutations: BRAF V600E (mutation fraction [MF] 34%), TERT E441del (MF 37%), RET N579K (MF 55%), EZH2 D154E (MF 60%), and CDK4 S259L (MF 48%). The patient had a dramatic response to the Dab/Tram combination with near complete resolution of his lung, bone, hepatic, and splenic lesions soon after starting therapy. Unfortunately, intolerable side effects (grade 2-3) on this regimen required tapering and discontinuation of the treatment. He had a quick resurgence of disease after stopping the combination therapy. The patient died approximately 3 months after discontinuing Dab/Tram. Autopsy revealed an atrophic thyroid gland with microscopic subcapsular focus of well-differentiated papillary thyroid carcinoma. There was extensive lymphatic spread of the tumor throughout bilateral lungs with fibrosis. No other metastatic site was identified. Conclusion. We report a unique case of ATC with 2 new mutations of EZH2 D154E and CDK S529L. This case exemplifies the significant promise Dab/Tram therapy holds, the potential side effects that limit their use, and autopsy findings status post use of this combination therapy.