Aggressive surgical resection of anaplastic thyroid carcinoma may provide long-term survival in selected patients

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Functional MRI applications for intra-axial brain tumours: uses and nuances in surgical practise

PURPOSE

Functional MRI (fMRI) has well-established uses to inform risks and plan maximally safe approaches in neurosurgery. In the field of brain tumour surgery, however, fMRI is currently in a state of clinical equipoise due to debate around both its sensitivity and specificity.

MATERIALS AND METHODS

In this review, we summarise the role and our experience of fMRI in neurosurgery for gliomas and metastases. We discuss nuances in the conduct and interpretation of fMRI that, based on our practise, most directly impact fMRI's usefulness in the neurosurgical setting.

RESULTS

Illustrated examples in which fMRI in our hands directly influences the neurosurgical treatment of brain tumours include evaluating the probability and nature of functional risks, especially for language functions. These presurgical risk assessments, in turn, help to predict the resectability of tumours, select or deselect patients for awake surgery, indicate the need for neurophysiological monitoring and guide the optimal use of intra-operative stimulation mapping. A further emerging application of fMRI is in measuring functional adaptation of functional networks after (partial) surgery, of potential use in the timing of further surgery.

CONCLUSIONS

In appropriately selected patients with a clearly defined surgical question, fMRI offers a valuable complementary tool in the pre-surgical evaluation of brain tumours. However, there is a great need for standards in the administration and analysis of fMRI as much as in the techniques that it is commonly evaluated against. Surprisingly little data exists that evaluates the accuracy of fMRI not just against complementary methods, but in terms of its ultimate clinical aim of minimising post-surgical morbidity.

Simvastatin Inhibits Cell Proliferation and Migration in Human Anaplastic Thyroid Cancer

Malignant human anaplastic thyroid cancer (ATC) is pertinacious to conventional therapies. The present study investigated the anti-cancer activity of simvastatin and its underlying regulatory mechanism in cultured ATC cells. Simvastatin (0–20 μM) concentration-dependently reduced cell viability and relative colony formation. Depletions of mevalonate (MEV) and geranylgeranyl pyrophosphate (GGpp) by simvastatin induced G1 arrest and increased apoptotic cell populations at the sub-G1 phase. Adding MEV and GGpp prevented the simvastatin-inhibited cell proliferation. Immunoblotting analysis illustrated that simvastatin diminished the activation of RhoA and Rac1 protein, and this effect was prevented by pre-treatment with MEV and GGpp. Simvastatin increased the levels of p21^cip and p27^kip proteins and reduced the levels of hyperphosphorylated-Rb, E2F1 and CCND1 proteins. Adding GGpp abolished the simvastatin-increased levels of p27^kip protein, and the GGpp-caused effect was abolished by Skp2 inhibition. Introduction of Cyr61 siRNA into ATC cells prevented the epidermal growth factor (EGF)-enhanced cell migration. The EGF-induced increases of Cyr61 protein expression and cell migration were prevented by simvastatin. Taken together, these results suggest that simvastatin induced ATC proliferation inhibition through the deactivation of RhoA/Rac1 protein and overexpression of p21^cip and p27^kip, and migration inhibition through the abrogation of Cyr61 protein expression.

The role of surgery in anaplastic thyroid cancer: A systematic review

OBJECTIVE

To elucidate the role of surgery in the management of anaplastic thyroid cancer.

METHODS

Ovid MEDLINE, Cochrane Library, and Google Scholar databases were searched for publications from December 2000 to July 2016. Selection criterion was a focus on the management of anaplastic thyroid cancer in adults. Studies addressing only nonsurgical management and review articles were excluded. Data extraction was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Kaplan-Meier analysis was performed on a subset of patients.

RESULTS

40 publications were included in the study. Approaches to unresectability and interpretations of resection varied widely. For patients undergoing primary surgery, the median survival was 6.6months. The median survival for non-surgical patients was 2.1months. In the subgroup analysis, the median survival time for patients undergoing surgery was significantly longer in Stage IVB (p=0.022) but not IVC disease. Negative margins did not afford a statistically significant survival benefit.

CONCLUSION

Surgery is a mainstay of treatment for Stage IVA and IVB disease. For Stage IVC cancer, distant metastasis was not a strict criterion against surgical candidacy among surgeons. The extent of resection and the definition of resectability remain controversial. Negative margins did not significantly increase survival.

Cell Cycle M-Phase Genes Are Highly Upregulated in Anaplastic Thyroid Carcinoma

BACKGROUND

Anaplastic thyroid carcinoma (ATC) accounts for only 3% of thyroid cancers, yet strikingly, it accounts for almost 40% of thyroid cancer deaths. Currently, no effective therapies exist. In an effort to identify ATC-specific therapeutic targets, we analyzed global gene expression data from multiple studies to identify ATC-specific dysregulated genes.

METHODS

The National Center for Biotechnology Information Gene Expression Omnibus database was searched for high-throughput gene expression microarray studies from human ATC tissue along with normal thyroid and/or papillary thyroid cancer (PTC) tissue. Gene expression levels in ATC were compared with normal thyroid or PTC using seven separate comparisons, and an ATC-specific gene set common in all seven comparisons was identified. We investigated these genes for their biological functions and pathways.

RESULTS

There were three studies meeting inclusion criteria, (including 32 ATC patients, 69 PTC, and 75 normal). There were 259 upregulated genes and 286 downregulated genes in ATC with at least two-fold change in all seven comparisons. Using a five-fold filter, 36 genes were upregulated in ATC, while 40 genes were downregulated. Of the 10 top globally upregulated genes in ATC, 4/10 (MMP1, ANLN, CEP55, and TFPI2) are known to play a role in ATC progression; however, 6/10 genes (TMEM158, CXCL5, E2F7, DLGAP5, MME, and ASPM) had not been specifically implicated in ATC. Similarly, 3/10 (SFTA3, LMO3, and C2orf40) of the most globally downregulated genes were novel in this context, while 7/10 genes (SLC26A7, TG, TSHR, DUOX2, CDH1, PDE8B, and FOXE1) have been previously identified in ATC. We experimentally validated a significant correlation for seven transcription factors (KLF16, SP3, ETV6, FOXC1, SP1, EGFR1, and MAFK) with the ATC-specific genes using microarray analysis of ATC cell lines. Ontology clustering of globally altered genes revealed that "mitotic cell cycle" is highly enriched in the globally upregulated gene set (44% of top upregulated genes, p-value <10^-30).

CONCLUSIONS

By focusing on globally altered genes, we have identified a set of consistently altered biological processes and pathways in ATC. Our data are consistent with an important role for M-phase cell cycle genes in ATC, and may provide direction for future studies to identify novel therapeutic targets for this disease.

Treatment and Prognosis of Anaplastic Thyroid Carcinoma: A Clinical Study of 50 Cases

INTRODUCTION

Although anaplastic thyroid carcinoma (ATC) is rare, it is one of the most aggressive human cancers. The optimal multimodal therapy policy of ATC is still debated, and a standardized treatment strategy remains to be established. This study aimed to evaluate the management aspect and prognosis of ATC.

MATERIALS AND METHODS

The data were analyzed retrospectively for 50 patients with ATC to evaluate the clinical characters, management and factors influencing survival. Survival analysis was performed by Kaplan-Merier method and log-rank test, and multivariate analysis was performed using Cox proportional hazard model.

RESULTS

The 1-year and 2-year overall survival rates (OS) were 48.0% and 26.0% respectively in all patients, with the 2-year OS of 40.0% and 31.0% and 6.3% for stage IVA, IVB and IVC respectively (P <0.05). In stage IVA and IVB patients, combined surgery with radiotherapy improved overall survival, and the 2-year OS were 50.0% and 35.7% respectively in the group with combined surgery with radiotherapy and the group with surgery with only (P <0.05). Postoperative radiotherapy improved local control rate in stage IVA and IVB patients (P <0.05). However, surgery, radiotherapy or chemotherapy could not improve the survival of stage IVC patients. Multivariate analysis showed that distant metastases, surgery, radiotherapy and tumor residue could predict the prognosis.

CONCLUSION

Combined surgery and radiotherapy could improve overall survival in stage IVA and IVB patients. Patients with ATC have a bad prognosis. Distant metastases, surgery, radiotherapy and tumor residue are the most important factors affecting the prognosis.

The prognostic impacts of postoperative radiotherapy in the patients with resected anaplastic thyroid carcinoma: A systematic review and meta-analysis

BACKGROUND

Optimal postoperative managements for anaplastic thyroid carcinoma (ATC) have not yet been sufficiently clarified. We conducted a systematic review and meta-analysis focussing on the impact of postoperative radiotherapy (PORT) in the patients with resected ATC.

MATERIALS AND METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a comprehensive search was performed in the several databases. We included the studies that reported survival outcome in the patients with or without PORT following any type of surgical resection except biopsy only. Hazard ratio (HR) was extracted, and the random-effects model was used for the pooled analysis.

RESULTS

Seventeen retrospective studies including 1147 analysable patients met all inclusion criteria. The overall research quality was relatively low with considerable methodological limitations. The pooled results showed that PORT significantly reduced the risk of death in all the patients with resected ATC compared with those with surgery alone (HR, 0.556; 95% confidence interval, 0.419-0.737; p < 0.001). Exploratory analyses demonstrated that patients with stage IVA (HR, 0.364; p = 0.012) and IVB (HR, 0.460; p = 0.059) may also have survival benefit from PORT, whereas stage IVC may not. No evidence of publication bias was found (p = 0.352).

CONCLUSIONS

This study is the first meta-analysis assessing PORT in patients with ATC and provides convincing evidence that adequate resection followed by PORT may offer the prolonged survival. However, without evidence based on prospective randomised trials, it is still not known which subset of patients can really benefit from PORT.

Anaplastic thyroid carcinoma: Failure of conventional therapy but hope of targeted therapy

BACKGROUND

Anaplastic thyroid cancer has a median survival between 1.2 and 10 months. The purpose of our study was to evaluate the outcomes of patients with anaplastic thyroid cancer in Ireland.

METHODS

We carried out a retrospective analysis of the Irish National Cancer Database for patients with anaplastic thyroid cancer between 2000 and 2010.

RESULTS

Of a total of 64 patients (40 women, 24 men), the median age was 69 years, and 29.7% of the patients had distant metastases. The overall median survival was 2.3 months and the 1, 2, and 5-year survival was 12.5%, 6.25%, and 4.69%, respectively. On univariate analysis age, sex, metastases at diagnosis, and multimodality treatment were statistically significant indicators of prognosis, and metastases at diagnosis remained statistically significant on multivariate analysis.

CONCLUSION

These results correlate with the American Thyroid Association (ATA) guidelines, in which, when possible, multimodality therapy offers a survival advantage to a select group of patients. Novel therapies may offer the greatest hope for these patients. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1122-E1129, 2016.

Targeting lipid metabolism for the treatment of anaplastic thyroid carcinoma

INTRODUCTION

Anaplastic thyroid carcinoma (ATC) is the rarest subtype of thyroid cancer; however, it disproportionately accounts for a large percentage of all thyroid cancer-related deaths and is considered one of the most lethal solid tumors in humans, having a median survival of only a few months upon diagnosis. Although a variety of treatment options are available including surgery, radiation and targeted therapies, response rates are low, due in part to the drug-resistant nature of this disease; therefore, new avenues for therapeutic intervention are surely needed. Recent investigation into the metabolic profile of ATC has revealed a tumor-specific dependency for increased de novo lipogenesis, offering new insight into the molecular mechanisms that govern disease initiation and progression.

AREAS COVERED

Herein we summarize known oncogenic signaling pathways and current therapeutic strategies for the treatment of ATC. We further discuss the unique expression pattern of lipid metabolism constituents in this disease. Additionally, the current literature correlating aberrant lipogenesis with carcinogenesis is reviewed, and the implications of targeting this pathway as an innovative approach for treating ATC and other malignancies are discussed. As stearoyl-CoA desaturase (SCD) is the most differentially expressed constituent of lipid metabolism in ATC, an additional focus on this enzyme as a novel therapeutic target is applied.

EXPERT OPINION

This section is used to summarize the current research efforts underway in defining the role of lipid metabolism specifically in thyroid carcinoma. Included is a brief summary of lipid metabolism factors for which inhibitors have been generated and are under current investigation as anti-cancer agents. Finally, research limitations regarding the use of these inhibitors against components of this pathway are discussed.

Noninvasive anaplastic thyroid carcinoma: report of a case and literature review

Anaplastic thyroid carcinoma (ATC) is an uncommon thyroid malignancy. Noninvasive ATC is a rare, surgically resectable variant with only four reported cases. We report a case of an 81-year-old man who presented with a 3.1 cm right thyroid lobe mass that on fine-needle aspiration biopsy was diagnosed as an ATC. Preoperative imaging revealed an encapsulated thyroid tumor without evidence of invasion of surrounding structures and no locoregional and distant metastases. A total thyroidectomy was performed that by histologic and immunohistochemical evaluation was diagnostic for a noninvasive ATC. Given the diagnosis of noninvasive ATC, adjuvant therapy was not administered. At 14 months following diagnosis, the patient remains disease free based on positron emission tomography/computed tomography imaging. A review of the outcomes of similar cases reported in the literature, as well as observations from our case, suggest a favorable prognosis for patients with noninvasive ATC. Noninvasive ATC may represent a distinct subset of resectable ATCs with an improved prognosis. The recently published American Thyroid Association (ATA) Guidelines for Management of Patients with ATC do not include this specific form of ATC. We encourage other authors to report similar cases in order to determine whether noninvasive ATC should be considered as a separate disease entity from the traditional highly lethal form of ATC.

The role of chemotherapy and latest emerging target therapies in anaplastic thyroid cancer

Anaplastic thyroid cancer represents 1%–2% of thyroid cancers. For its aggressiveness, it is considered a systemic disease at the time of diagnosis. Surgery remains the cornerstone of therapy in resectable tumor. Traditional chemotherapy has little effect on metastatic disease. A multimodality approach, incorporating cytoreductive surgical resection, chemoradiation, either concurrently or sequentially, and new promising target therapies is advisable. Doxorubicin is the most commonly used agent, with a response rate of 22%. Recently, other chemotherapy agents have been used, such as paclitaxel and gemcitabine, with superimposable activity and response rates of 10%–20%. However, survival of patients with anaplastic thyroid cancer has changed little in the past 50 years, despite more aggressive systemic and radiotherapies. Several new agents are currently under investigation. Some of them, such as sorafenib, imatinib, and axitinib have been tested in small clinical trials, showing promising disease control rates ranging from 35%–75%. Referral of patients for participation in clinical trials is needed.