Treatment outcomes of radiotherapy for anaplastic thyroid cancer

Anaplastic Thyroid Carcinoma Mimicking Cervical Tuberculosis: A Case Report

Anaplastic thyroid carcinoma is a rare and aggressive form of thyroid cancer that has a poor prognosis and a high mortality rate. It is characterized by rapid growth and invasion of nearby tissues. It typically presents as a rapidly growing goiter or nodule that is firm to the touch and firmly attached to the underlying structures. Case reports of unusual presentations of anaplastic thyroid carcinoma have been reported. The presentation of anaplastic thyroid carcinoma mimicking cervical tuberculosis is very unusual. We reported a case of a 65-year-old patient who had a left cervical swelling that had been evolving for 4 months, causing dysphagia. Initial imaging showed a necrotic mass in the left lobe of the thyroid, communicating with a second necrotic mass in the subcutaneous tissue that was fistulized to the skin and suggesting cervical tuberculosis. The mass was incised with pus and whitish material resembling caseous tuberculosis was discharged. Acid-fast bacilli (AFB) Polymerase chain reaction (PCR) was negative and biopsy revealed a nonspecific granulomatous lesion. Due to the growth of the mass and the presence of a permeation nodule, a second biopsy was performed, revealing anaplastic thyroid carcinoma. The patient was referred for radiochemotherapy due to tumor inoperability.

Prognostic factors in radiotherapy of anaplastic thyroid carcinoma: a single center study over 31 years

BACKGROUND

Anaplastic thyroid carcinoma has a very poor prognosis. We analyzed the effect of surgery, radiotherapy and chemotherapy on survival time and side effects in patients with ATC.

METHODS

We retrospectively analyzed all patients (n = 63) with histologically confirmed ATC who presented at our clinic between 1989 and 2020. We analyzed the survival with Kaplan-Meier curves and cox proportional hazard models and acute toxicities with logistic regression models.

RESULTS

Out of 63 patients, 62 received radiotherapy, 74% underwent surgery and 24% received combined chemotherapy. A median radiation dose of 49 Gy (range 4-66 Gy) was applied. In 32% of the cases opposing-field technique was used, in 18% 3D-conformal, in 27% a combination of opposing field and 3D-conformal technique and 21% obtained IMRT (intensity modulated radiotherapy) or VMAT (volumetric modulated arc radiotherapy). Median overall survival (OS) was 6 months. We identified five predictive factors relevant for survival: absence of distant metastases at the time of diagnosis (OS 8 months), surgery (OS 9.8 months), resection status R0 (OS 14 months), radiation dose of 50 Gy or higher (OS 13 months) and multimodal therapy (surgery, radiotherapy and chemotherapy) with a median OS of 9.7 months.

CONCLUSION

In spite of the dismal outcome, longer survival can be achieved in some patients with ATC using surgery and radiotherapy with a high radiation dose. Compared to our previous study, there are no significant advantages in overall survival. Trial registration Retrospectively registered.

Association of Treatment Strategies and Tumor Characteristics With Overall Survival Among Patients With Anaplastic Thyroid Cancer: A Single-Institution 21-Year Experience

Importance

Survival outcomes for anaplastic thyroid cancer (ATC), the most aggressive subtype of thyroid cancers, have remained poor. However, targeted therapies and immunotherapies present new opportunities for treatment of this disease. Evaluations of survival outcomes over time with new multimodal therapies are needed for optimizing treatment plans.

Objective

To evaluate the association of treatment strategies and tumor characteristics with overall survival (OS) among patients with ATC.

Design, Setting, and Participants

This retrospective case series study evaluated the survival outcomes stratified by treatment strategies and tumor characteristics among patients with ATC treated at a tertiary level academic institution from January 1, 2000, to December 31, 2021. Demographic, tumor, treatment, and outcome characteristics were analyzed. Kaplan-Meier method and log rank test modeled OS by treatment type and tumor characteristics. Data were analyzed in May 2022.

Main Outcomes and Measures

Overall survival (OS).

Results

The study cohort comprised 97 patients with biopsy-proven ATC (median [range] age at diagnosis, 70 [38-93] years; 60 (62%) female and 85 [88%] White individuals; 59 [61%] never smokers). At ATC diagnosis, 18 (19%) patients had stage IVA, 19 (20%) had stage IVB, and 53 (55%) had stage IVC disease. BRAF status was assessed in 38 patients; 18 (47%) had BRAF-V600E variations and 20 (53%), BRAF wild type. Treatment during clinical course included surgery for 44 (45%) patients; chemotherapy, 41 (43%); definitive or adjuvant radiation therapy, 34 (RT; 35%); and targeted therapy, 28 (29%). Median OS for the total cohort was 6.5 (95% CI, 4.3-10.0) months. Inferior OS was found in patients who did not receive surgery (hazard ratio [HR], 2.12; 95% CI, 1.35-3.34; reference, received surgery), chemotherapy (HR, 3.28; 95% CI, 1.99-5.39; reference, received chemotherapy), and definitive or adjuvant RT (HR, 2.47; 95% CI, 1.52-4.02; reference, received definitive/adjuvant RT). On multivariable analysis, age at diagnosis (HR, 1.03; 95% CI, 1.01-1.06), tumor stage IVC (HR, 2.65; 95% CI, 1.35-5.18), and absence of definitive or adjuvant RT (HR, 1.90; 95% CI, 1.01-3.59) were associated with worse OS.

Conclusions and Relevance

This retrospective single-institution study found that lower tumor stage, younger age, and the ability to receive definitive or adjuvant RT were associated with improved OS in patients with ATC.

External beam radiotherapy for thyroid cancer: Patients, complications, and survival

BACKGROUND

Patterns of utilization of external beam radiation therapy (EBRT) in thyroid cancer are incompletely described. We characterize therapeutic intent, complications, and survival in thyroid cancer treated with EBRT.

METHODS

In this retrospective study of 105 thyroid cancer patients treated with EBRT at one institution (2008-2018), the primary outcome was overall survival. Secondary outcomes included incomplete treatment, emergency department (ED) visits, weight change, and gastrostomy placement.

RESULTS

Dominant histopathology was differentiated (44%), anaplastic (45%) and poorly-differentiated (11%) disease. EBRT was mainly utilized for locoregional control (differentiated 87%, poorly-differentiated 75%, anaplastic 92%). Palliative EBRT was more common in poorly-differentiated disease (42%). Weight loss was greater in aggressive/advanced disease (differentiated 10 lb, poorly-differentiated 27 lb, anaplastic 18 lb). Anaplastic cancer had higher rates of gastrostomy (34%) and lowest rates of treatment completion (83%). ED encounters were common (differentiated 44%, poorly-differentiated 50%, anaplastic 45%). Gastrostomy was associated with mortality on multivariable analysis in non-anaplastic malignancy.

CONCLUSIONS

EBRT was most frequently administered for locoregional control in thyroid cancer. Despite complications, the majority of patients completed EBRT therapy.

Anaplastic thyroid cancer: An update

Anaplastic thyroid cancer (ATC) is one of the most lethal of all cancers. It is more common in women and occurs primarily in older patients. ATC has a median overall survival of 3-5 months and a nearly 100% disease-specific mortality. It is known to spread rapidly to locoregional structures as well as outside the neck to distant sites, hence ATC is always considered stage IV. With better understanding of the disease at a molecular level, the introduction of newer treatment strategies has been possible and is part of the multimodal (surgery, radiation, and systemic therapy) therapeutic approach. However, there is extensive work needed to achieve better survival outcomes.

Thyroid Carcinoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Differentiated thyroid carcinomas is associated with an excellent prognosis. The treatment of choice for differentiated thyroid carcinoma is surgery, followed by radioactive iodine ablation (iodine-131) in select patients and thyroxine therapy in most patients. Surgery is also the main treatment for medullary thyroid carcinoma, and kinase inhibitors may be appropriate for select patients with recurrent or persistent disease that is not resectable. Anaplastic thyroid carcinoma is almost uniformly lethal, and iodine-131 imaging and radioactive iodine cannot be used. When systemic therapy is indicated, targeted therapy options are preferred. This article describes NCCN recommendations regarding management of medullary thyroid carcinoma and anaplastic thyroid carcinoma, and surgical management of differentiated thyroid carcinoma (papillary, follicular, Hürthle cell carcinoma).

Risk stratification in patients with anaplastic thyroid carcinoma: role of age

BACKGROUND

Thyroid carcinoma is the only cancer that regards age as an important predictor of thyroid cancer-specific survival (CSS). While the 8th American Joint Committee on Cancer (AJCC) staging system raised the age cutoff from 45 to 55 years for differentiated thyroid carcinoma (DTC) to more accurately predict the prognosis, there is no new information regarding the role of age in the prognosis of anaplastic thyroid carcinoma (ATC). The aim of this study was to determine the optimal age cutoff values for mortality risk stratification in ATC patients. Furthermore, a nomogram to predict ATC CSS was developed in each age group.

METHODS

Patients diagnosed with ATC between 2004 and 2015 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. After applying inclusion and exclusion criteria, a total of 1140 patients were enrolled as cohort 1 to describe the characteristics of ATC, while a total of 556 patients were included as cohort 2 to determine age cutoff values for risk stratification by X-tile program. Training set and testing set were randomly generated to develop and validate a predictive nomogram of CSS in each age group.

RESULTS

The 6-month, 1-year, and 2-year survival was 27.6%, 15.1%, and 6.2%, respectively, in cohort 1. X-tile program results showed that the optimal age cutoff values for mortality risk stratification were 65 and 85 years old (p < 0.001). Distant metastasis was independently associated with CSS in patients younger than 85 years old, and these patients benefited more from complete resection of the tumor and radiotherapy/chemotherapy. However, no predictors of CSS were identified in patients over 85 years old, and interventions (surgery, radiotherapy, and chemotherapy) targeting ATC had little role in disease control in these patients. The nomogram was developed and validated based on the independent CSS predictors in each age group. The C-index values of the training set and testing set were 0.735 [95% CI, 0.696-0.774] and 0.733 [95% CI, 0.663-0.804] for CSS in patients of ≤64 years old, while the values were 0.767 [95% CI, 0.730-0.804] and 0.783 [95% CI, 0.718-0.848] in patients of 65-84 years old. All of the C-index values were larger than 0.7, which showed acceptable prediction performance of the nomograms.

CONCLUSIONS

Age can be used as an auxiliary stratification factor of prognosis in ATC patients. The survival may be improved in patients younger than 85 years old if combination therapy (surgery, radiotherapy, and chemotherapy) was indicated and applicable, while no optimal therapeutic strategy was determined in patients older than 85 years old. The established nomograms can provide good prediction of CSS according to age group.

Radio(chemo)therapy in anaplastic thyroid cancer-high locoregional but low distant control rates-a monocentric analysis of a tertiary referral center

BACKGROUND

Anaplastic thyroid cancer (ATC) is a lethal disease with highly aggressive disease progression. This study analyses the influence of radio(chemo)therapy, R(C)T, on disease control, survival rates and predictors for survival.

PATIENTS AND METHODS

A total of 33 patients with ATC, treated at a tertiary referral center between May 2001 and April 2020 were included. Univariate and multivariate analysis were used to investigate correlates of R(C)T and predictors on disease control and survival rates.

RESULTS

Median follow-up was 4 months. In UICC stage IVA and IVB median overall survival (OS) was 8 months, median progression-free survival (PFS) was 6 months. Patients with UICC stage IVA and IVB and patients being irradiated with a radiation dose of more than 60 Gy showed increased OS. Of these patients, 3 were alive and free from disease. All of them receiving cisplatin-based radiochemotherapy and a minimum radiation dose of 66 Gy. UICC stage IVC showed a median OS of 2.5 months and a median PFS of 1 month. Only 2 of 16 patients had local failure.

CONCLUSION

Depending on UICC stage, RT with high radiation dose can lead to improved OS or at least higher locoregional control. A limiting factor is the high incidence of distant metastases; therefore modern systemic treatment options should be integrated into multimodal therapy concepts.

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.

Anticancer Effects of Ursi Fel Extract and Its Active Compound, Ursodeoxycholic Acid, in FRO Anaplastic Thyroid Cancer Cells

Anaplastic thyroid cancer (ATC) is one of the most fatal human malignancies. Ursi Fel (UF) is the bile of a brown bear that has been traditionally used for heat clearance and toxin relief in Korean and Chinese medicines. In this study, we determined the anticancer effects of a UF extract and its active compound, ursodeoxycholic acid (UDCA), in FRO human ATC cells. FRO cells were treated with UF extract and UDCA at different concentrations for various durations. Cell viability was measured using an MTT assay. Cell apoptosis was investigated by flow cytometric analysis following Annexin V and propidium iodide (PI) staining, and Hoechst staining was used to observe nuclear fragmentation. The expression of pro-apoptotic (Bax, caspase-3, cytochrome c, and PARP), anti-apoptotic (Bcl-2), and angiogenetic (TGF-β, VEGF, N-cadherin, and sirtuin-1) proteins and the phosphorylation of Akt and mechanistic target of rapamycin (mTOR) were determined by western blot analysis. Treatment with UF extract at 10, 25, and 50 μg/mL and UDCA at 25, 50, and 100 μM/mL significantly inhibited the growth of FRO cells in a dose-dependent manner. Flow cytometry and Hoechst staining revealed an increase in the apoptosis of FRO cells mediated by UF extract and UDCA in a dose-dependent manner. UF extract (25 and 50 μg) and UDCA (50 and 100 μM) significantly increased the expression of Bax, caspase-3, cytochrome c, and PARP and inhibited the expression of Bcl-2, TGF-β, VEGF, N-cadherin, and sirtuin-1 in FRO cells. Furthermore, UF extract and UDCA treatment stimulated Akt phosphorylation and inhibited mTOR phosphorylation in these cells. These results indicate that UF extract and UDCA exert anticancer properties in FRO cells by inducing apoptosis and inhibiting angiogenesis via regulating the Akt/mTOR signaling pathway.

Prognostic Value of the Neutrophil-to-Lymphocyte Ratio before and after Radiotherapy for Anaplastic Thyroid Carcinoma

Simple Summary

Systemic hematologic markers such as the neutrophil–lymphocyte ratio (NLR) are attracting attention in a simple blood test predicting survival and treatment outcomes in various solid cancers. In our study including 40 patients with anaplastic thyroid cancer (ATC) who underwent radiotherapy, we found that high NLR before and after radiotherapy was associated with poor survival. This study result means that host immunity has an important role in patients with ATC, which can be important information for designing future investigations on the impact of immune system modulating therapy in ATC.

Abstract

The neutrophil–lymphocyte ratio (NLR) is a marker of systemic inflammation, and its elevation has recently been associated with poor survival in many solid cancers. Leukocyte elevation and lymphocyte reduction are associated with a poor response to radiotherapy (RT). This study aimed to assess the prognostic value of NLR before and after RT for anaplastic thyroid carcinoma (ATC). This retrospective study analyzed 40 patients with ATC who received RT with available complete blood cell count data from November 1995 through May 2020 at Samsung Medical Center (Seoul, Korea). Patients were classified into two groups according to the NLR before and after RT. The median overall survival (OS) was 8.9 months (range, 3.5–18.2) in the low NLR group (<3.47) and 5.2 months (range, 2.7–7.5) months in the high NLR group (≥3.47). The association between NLR and OS was also observed in multivariable Cox regression analysis (hazard ratio, 3.18; 95% confidence interval, 1.15–8.85; p = 0.026). The OS curves differed significantly according to post-RT NLR (p = 0.036). A high NLR before and after RT may be significantly associated with poor OS in patients with ATC who receive RT.

Extracellular Vesicles Act as Nano-Transporters of Tyrosine Kinase Inhibitors to Revert Iodine Avidity in Thyroid Cancer

A new approach for using extracellular vesicles (EVs) to deliver tyrosine kinase inhibitors (TKIs) to enhance iodine avidity in radioactive iodine-refractory thyroid cancer is needed. We isolated and characterized primary human adipose-derived stem cells (ADSCs) and isolated their EVs. The EVs were characterized by transmission electron microscopy, nanoparticle tracking analysis, and western blotting. A new TKI was loaded into the EVs by incubation (37 °C; 10 min) or sonication (18 cycles; 4 s per cycle) with 2 s intervals and a 2 min ice bath every six cycles. TKI loading was confirmed and measured by mass spectrometry. EV uptake into radioactive iodine-refractory thyroid cancer cells (SW1736 cells) was confirmed by microscopy. We treated the SW1736 cells with vehicle, TKI, or TKI-loaded EVs (sonication TKI-loaded EVs [EVs^TKI(S)]) and examined the expression of iodide-metabolizing proteins and radioiodine uptake in the SW1736 cells. ADSCs cells showed >99% of typical stem cell markers, such as CD90 and CD105. The EVs displayed a round morphology, had an average size of 211.4 ± 3.83 nm, and were positive for CD81 and Alix and negative for cytochrome c. The mass spectrometry results indicate that the sonication method loaded ~4 times more of the TKI than did the incubation method. The EVs^TKI(S) were used for further experiments. Higher expression levels of iodide-metabolizing mRNA and proteins in the EVs^TKI(S)-treated SW1736 cells than in TKI-treated SW1736 cells were confirmed. EVs^TKI(S) treatment enhanced ¹²⁵I uptake in the recipient SW1736 cells compared with free-TKI treatment. This is the first study that demonstrated successful delivery of a TKI to radioactive iodine-refractory thyroid cancer cells using EVs as the delivery vehicle. This approach can revert radioiodine-resistant thyroid cancer cells back to radioiodine-sensitive thyroid cancer cells.

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.

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.

Sesquiterpene Lactones from Calea pinnatifida: Absolute Configuration and Structural Requirements for Antitumor Activity

This work describes the chromatographic fractionation of the aerial parts of Calea pinnatifida and the structural characterization and determination of the absolute configuration of the isolated compounds as well as their antitumor potential. The HPLC fractionation of the CH₂Cl₂ phase of the MeOH extract from the leaves of C. pinnatifida led to the isolation of two related sesquiterpene lactones (STLs): calein C (1) and calealactone B (2). Additionally, during the purification process, a derivative of calein C (3) was formed as a product of the Michael addition of MeOH. The structures of Compounds 1–3 were established based on spectroscopic and spectrometric data, while the absolute stereochemistry was established by vibrational circular dichroism. In order to evaluate the effect of the conjugated double bonds on the cytotoxic activity of STLs, Compounds 1–3 were tested against anaplastic (KTC-2) and papillary (TPC-1) thyroid carcinoma cells. Calein C was the most active of the STLs, and displayed activity against both KTC-2 and TPC-1. On the other hand, the calein C derivative (3) was the least cytotoxic of all the compounds tested. These results are promising and suggest the importance of studying sesquiterpene lactones isolated from C. pinnatifida in terms of antitumor activity, especially considering the effects of α,β-unsaturated carbonyl systems.

Differential MicroRNA-Signatures in Thyroid Cancer Subtypes

Thyroid cancer is one of the most common endocrine cancers, with an increasing trend in the last few decades. Although papillary thyroid cancer is the most frequent subtype compared with follicular or anaplastic thyroid cancer, it can dedifferentiate to a more aggressive phenotype, and the recurrence rate is high. The cells of follicular adenomas and follicular carcinomas appear identical in cytology, making the preoperative diagnosis difficult. On the other hand, anaplastic thyroid cancer poses a significant clinical challenge due to its aggressive nature with no effective therapeutic options. In the past several years, the roles of genetic alterations of thyroid tumors have been documented, with a remarkable correlation between genotype and phenotype, indicating that distinct molecular changes are associated with a multistep tumorigenic process. Besides mRNA expression profiles, small noncoding microRNA (miRNA) expression also showed critical functions for cell differentiation, proliferation, angiogenesis, and resistance to apoptosis and finally activating invasion and metastasis in cancer. Several high-throughput sequencing studies demonstrate that miRNA expression signatures contribute clinically relevant information including types of thyroid cancer, tumor grade, and prognosis. This review summarizes recent findings on miRNA signatures in thyroid cancer subtypes.

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.

Survival advantage of chemoradiotherapy in anaplastic thyroid carcinoma: Propensity score matched analysis with multiple subgroups

BACKGROUND

We compared overall survival (OS) between radiation therapy (RT) and chemoradiotherapy (CRT) in patients with anaplastic thyroid carcinoma (ATC) using a large database.

METHODS

The National Cancer Data Base was queried for ATC patients diagnosed between 2004 and 2013 who received RT or CRT. Groups were balanced by propensity score matching (PSM) on nine relevant variables. OS was also examined in five paired subgroups given known patient heterogeneity.

RESULTS

Of 858 total patients, 575 received CRT and 283 received RT. CRT was associated with decreased risk of death (hazard ratio [HR] 0.66, P < .001), 1-year OS 25.5% vs 14.3%. A survival advantage to CRT was seen using PSM cohorts (HR 0.75, P = .006). Those receiving definitive surgery saw the greatest benefit to CRT over RT (HR 0.65, P = .009), 1-year OS 39.6% vs 20.4%.

CONCLUSIONS

CRT is associated with decreased risk of death in ATC; the magnitude of CRT vs RT benefit varied by subgroup.

Treatment Outcomes in Anaplastic Thyroid Cancer

BACKGROUND

Anaplastic thyroid cancer (ATC) is rare, accounting for 1-2% of thyroid malignancies. Median survival is only 3-10 months, and the optimal therapeutic approach has not been established. This study aimed to evaluate outcomes in ATC based on treatment modality.

METHODS

Retrospective review was performed for patients treated at a single institution between 1990 and 2015. Demographic and clinical covariates were extracted from the medical record. Overall survival (OS) was modeled using Kaplan Meier curves for different treatment modalities. Univariate and multivariate analyses were conducted to assess the relationships between treatment and disease characteristics and OS.

RESULTS

28 patients with ATC were identified (n = 16 female, n = 12 male; n = 22 Caucasian, n = 6 African-American; median age 70.9). Majority presented as Stage IVB (71.4%). Most patients received multimodality therapy. 19 patients underwent local surgical resection. 21 patients received locoregional external beam radiotherapy (EBRT) with a median cumulative dose of 3,000 cGy and median number of fractions of 16. 14 patients received systemic therapy (n = 11 concurrent with EBRT), most commonly doxorubicin (n = 9). 16 patients were never disease free, 11 patients had disease recurrence, and 1 patient had no evidence of disease progression. Median OS was 4 months with 1-year survival of 17.9%. Regression analysis showed that EBRT (HR: 0.174; 95% CI: 0.050-0.613; p=0.007) and surgical resection (HR: 0.198; 95% CI: 0.065-0.598; p=0.004) were associated with improved OS. Administration of chemotherapy was not associated with OS.

CONCLUSIONS

Anaplastic thyroid cancer patients receiving EBRT to the thyroid area/neck and/or surgical resection had better OS than patients without these therapies, though selection bias likely contributed to improved outcomes since patients who can undergo these therapies tend to have better performance status. Prognosis remains poor overall, and new therapeutic approaches are needed to improve outcomes.

PI3K blockage synergizes with PLK1 inhibition preventing endoreduplication and enhancing apoptosis in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is among the most lethal malignancies. The mitotic kinase PLK1 is overexpressed in the majority of ATCs and PLK1 inhibitors have shown preclinical efficacy. However, they also cause mitotic slippage and endoreduplication, leading to the generation of tetraploid, genetically unstable cell populations. We hypothesized that PI3K activity may facilitate mitotic slippage upon PLK1 inhibition, and thus tested the effect of combining PLK1 and PI3K inhibitors in ATC models, in vitro and in vivo. Treatment with BI6727 and BKM120 resulted in a significant synergistic effect in ATC cells, independent of the levels of AKT activity. Combination of the two drugs enhanced growth suppression at doses for which the single drugs showed no effect, and led to a massive reduction of the tetraploid cells population. Furthermore, combined treatment in PI3Khigh cell lines showed a significant induction of apoptosis. Finally, combined inhibition of PI3K and PLK1 was extremely effective in vivo, in an immunocompetent allograft model of ATC. Our results demonstrate a clear therapeutic potential of combining PLK1 and PI3K inhibitors in anaplastic thyroid tumors.