Randomized safety and efficacy study of fosbretabulin with paclitaxel/carboplatin against anaplastic thyroid carcinoma

Therapeutic advances in anaplastic thyroid cancer: a current perspective

Thyroid cancer incidence is increasing at an alarming rate, almost tripling every decade. In 2017, it was the fifth most common cancer in women. Although the majority of thyroid tumors are curable, about 2-3% of thyroid cancers are refractory to standard treatments. These undifferentiated, highly aggressive and mostly chemo-resistant tumors are phenotypically-termed anaplastic thyroid cancer (ATC). ATCs are resistant to standard therapies and are extremely difficult to manage. In this review, we provide the information related to current and recently emerged first-line systemic therapy (Dabrafenib and Trametinib) along with promising therapeutics which are in clinical trials and may be incorporated into clinical practice in the future. Different categories of promising therapeutics such as Aurora kinase inhibitors, multi-kinase inhibitors, epigenetic modulators, gene therapy using oncolytic viruses, apoptosis-inducing agents, and immunotherapy are reviewed. Combination treatment options that showed synergistic and antagonistic effects are also discussed. We highlight ongoing clinical trials in ATC and discuss how personalized medicine is crucial to design the second line of treatment. Besides using conventional combination therapy, embracing a personalized approach based on advanced genomics and proteomics assessment will be crucial to developing a tailored treatment plan to improve the chances of clinical success.

Lenvatinib as a novel treatment for anaplastic thyroid cancer: A retrospective study

Anaplastic thyroid cancer (ATC) is associated with an extremely poor prognosis and is resistant to the majority of chemotherapies. In 2015, lenvatinib was approved for treating ATC in Japan. The present study aimed to evaluate the overall survival (OS) of patients with ATC treated with lenvatinib. A total of 23 patients with a definitive histological diagnosis of ATC who were treated at Kanagawa Cancer Center (Yokohama, Kanagawa. Japan) were enrolled. Surgical treatment was possible in 10 patients (including one debulking surgery), and lenvatinib treatment was postoperatively started. The remaining 13 patients were not eligible for debulking surgery; thus, lenvatinib was promptly approved as a life-saving treatment. The therapeutic effect was determined according to the Response Evaluation Criteria In Solid Tumors criteria (ver.1.1). The patients exhibited a lenvatinib response rate of 17.4% and a disease control rate of 43.5%. However, lenvatinib was associated with a 100% incidence of treatment-related adverse events (AEs), with hypertension being the most common AE (91.3%). Additionally, dose interruptions and reductions were required due to the development of tumor fistulas or other tumor-related AEs, and 9 (39.1%) patients discontinued treatment due to grade 3 or higher AEs. The median OS time was 166 days. Overall, the present study demonstrated the effectiveness of lenvatinib against ATC, which is often chemotherapy-resistant. Successful treatment of fistulas developing due to tumor necrosis at the site of the primary lesion is crucial for improving the patient outcome. The response to lenvatinib in patients with ATC varies on a case-by-case basis and requires further investigation in future studies.

Optimal combination of treatment modality to increase survival in patients with anaplastic thyroid carcinoma: A STROBE compliant retrospective study

There is little consensus on the optimal treatment approach for newly diagnosed patients. The present study aims to provide additional evidence by evaluating a series of patients diagnosed with anaplastic thyroid carcinoma (ATC) and analyzing factors related to increased survival. This was a retrospective cohort report structured according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline. Demographics, chief complaint, history of prior thyroid cancer, stage at presentation, management modalities (surgery, chemotherapy, radiotherapy, or observation), completeness or resection, and survival period since initial diagnosis were reviewed for patients with documentation of histologic ATC diagnosis between 2003 and 2016. The median survival period for 34 patients (11 males, 23 females) was 93.5 days. Patients aged 70 or younger (111 days) tended to survive longer than those older 70 (88 days) (P = .081). Observation, surgery only, radiotherapy only, and chemo-radiotherapy after surgery group showed median survival of 88 days, 49 days (range 14-528), 61.5 days, and 225 days, respectively. There was also no significant difference in survival between the 10 (29.4%) stage IVb (225 days) and 23 (67.7%) IVc (88 days) patients (P = .242). The median survival of the R1 resection group was 514 days while that of the R2 group was 102 days (P = .338). There were no significant difference between patients with the de novo ATC (112 days) and patients with papillary thyroid carcinoma origin ATC (99 days) (P = .297). Results from our series of 34 patients with ATC show that more intense combination of surgery and chemo-radiotherapy tends to secure a longer survival period. Therefore we recommend a multi-modality approach after a comprehensive consultation with the patient.

Anaplastic thyroid carcinoma: review of treatment protocols

Anaplastic thyroid carcinoma (ATC) is an orphan disease and in most patients fatal. So far no established treatment is available that prolongs survival. Several large retrospective studies have identified negative prognostic markers, analyzed efficacy of multimodal approaches such as radiotherapy with and without concurrent chemotherapy and chemotherapy protocols. Recently, single case reports have suggested some effectiveness of newer therapies targeting single somatic alterations in ATC. Overall, the conclusions that can be drawn from published retrospective studies and the scarce prospective approaches is that new treatment protocols should be developed including surgery, radiotherapy, chemotherapy and targeted therapy approaches and combinational therapy with immunotherapies. These protocols then need to be evaluated prospectively to improve ATC patients' outcome in routine care.

Refractory thyroid carcinoma: which systemic treatment to use?

The incidence of thyroid cancer has increased markedly in recent decades, but has been stable in terms of mortality rates. For the most part, these cancers are treated with surgery, which may or may not be followed by radioactive iodine depending on the tumor subtype. Still, many of these cancers will recur and may be treated with radioactive iodine or another surgery. It is unclear what treatment is best for cases of locally advanced or metastatic thyroid cancer that are refractory to radioactive iodine. Chemotherapy has a very low response rate. However, in the past few years, several systemic therapies, primarily targeted, have emerged to improve the overall survival of these patients. Alternative treatments are also of interest, namely peptide receptor radionuclide therapy or immunotherapy.

Recent advances and emerging therapies in anaplastic thyroid carcinoma

Anaplastic thyroid cancer is a rare and aggressive thyroid cancer with an overall survival measured in months. Because of this poor prognosis and often advanced age at presentation, these patients have traditionally been treated palliatively and referred for hospice. However, recent progress using novel therapies has energized the field, and several promising clinical trials are now available for these patients. This review will highlight this progress and the potential treatments that could pave the way to improved outcomes and quality of life for patients with this disease.

Clinical trial experience with CA4P anticancer therapy: focus on efficacy, cardiovascular adverse events, and hypertension management

Combretastatin A4-phosphate (CA4P) is a vascular-disrupting agent (VDA) in clinical development for the treatment of ovarian and other cancers. In contrast to antiangiogenic agents, such as bevacizumab, which suppress the development of new tumor vasculature, VDAs target established tumor vasculature. These differing but complementary mechanisms of action are currently being explored in clinical trials combining CA4P and bevacizumab. Clinical experience to date has highlighted an important need to better understand the cardiovascular adverse events of CA4P, both alone and in combination with antiangiogenic agents, which can also be associated with cardiovascular adverse events.

An acute but transient increase in blood pressure is often the most clinically relevant toxicity associated with CA4P. Increases in CA4P-related blood pressure typically occur 0.5 to 1 h after initiation of the 10-min infusion, peak by 2 h, and return to baseline 3 to 4 h after the infusion. Post-infusion increases in blood pressure are likely to recur in subsequent treatment cycles; however, the severity does not appear to increase with successive cycles. Other cardiovascular adverse events, such as transient, predominantly grade 1–2 tachycardia, bradycardia, QTc prolongation, and in rare cases myocardial ischemia, have also been observed with CA4P but at markedly lower frequencies than hypertension.

The clinical trial experience with CA4P suggests that cardiovascular assessment of patients prior to CA4P treatment and careful management of blood pressure during CA4P treatment can largely mitigate the risk of cardiovascular adverse events. Accordingly, we have developed a blood pressure management algorithm for use in the ongoing phase II/III FOCUS study of the triple combination of CA4P with physician’s choice chemotherapy and bevacizumab.

Real-World Experience with Targeted Therapy for the Treatment of Anaplastic Thyroid Carcinoma

BACKGROUND

Patients with anaplastic thyroid cancer (ATC) have a dismal prognosis, despite systemic cytotoxic chemotherapy. The objective of this study was to investigate the efficacy and safety of targeted therapy in ATC patients when used outside of a clinical trial.

METHODS

This is a retrospective review from April 2015 to May 2016 at a single academic institution where 16 ATC patients receiving targeted therapy outside of a clinical trial were studied. Ten patients (eight BRAF wild type and two BRAFV600E mutant tumors) were started on lenvatinib, and six with BRAFV600E-mutated tumors received a combination of dabrafenib plus trametinib. Best response evaluated by RECIST v1.1, progression-free survival, and overall survival were determined. Adverse events were evaluated for safety.

RESULTS

The majority of patients (63%) were men, and all had distant metastases or radiation-resistant primary disease at the time of treatment. In the entire cohort, 6/16 (38%) had a partial response, 6/16 (38%) had stable disease, and 2/16 (12%) had progressive disease. Two (12%) patients died before restaging. Median follow-up time was 11.8 months. Median progression-free survival was 3.7 months [confidence interval 1.8-7.6] in the entire cohort, 2.7 months for lenvatinib, and 5.2 months for dabrafenib plus trametinib. Median OS was 6.3 months [confidence interval 1.8-7.6] for the entire cohort, 3.9 months for lenvatinib, and 9.3 months for dabrafenib plus trametinib. Adverse events were as expected and manageable.

CONCLUSIONS

Targeted therapies, lenvatinib, and dabrafenib plus trametinib (for BRAFV600E mutants) may provide clinical benefit in ATC patients who are unable to participate in clinical trials, and toxicities are manageable.

Carfilzomib potentiates CUDC-101-induced apoptosis in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the most aggressive human malignancies, with no effective treatment currently available. Previously, we identified agents active against ATC cells, both in vitro and in vivo, using quantitative high-throughput screening of 3282 clinically approved drugs and small molecules. Here, we report that combining two of these active agents, carfilzomib, a second-generation proteasome inhibitor, and CUDC-101, a histone deacetylase and multi-kinase inhibitor, results in increased, synergistic activity in ATC cells. The combination of carfilzomib and CUDC-101 synergistically inhibited cellular proliferation and caused cell death in multiple ATC cell lines harboring various driver mutations observed in human ATC tumors. This increased anti-ATC effect was associated with a synergistically enhanced G2/M cell cycle arrest and increased caspase 3/7 activity induced by the drug combination. Mechanistically, treatment with carfilzomib and CUDC-101 increased p21 expression and poly (ADP-ribose) polymerase protein cleavage. Our results suggest that combining carfilzomib and CUDC-101 would offer an effective therapeutic strategy to treat ATC.

Anaplastic thyroid carcinoma: from clinicopathology to genetics and advanced therapies

Anaplastic thyroid carcinoma (ATC) is a rare malignancy, accounting for 1-2% of all thyroid cancers. Although rare, ATC accounts for the majority of deaths from thyroid carcinoma. ATC often originates in a pre-existing thyroid cancer lesion, as suggested by the simultaneous presence of areas of differentiated or poorly differentiated thyroid carcinoma. ATC is characterized by the accumulation of several oncogenic alterations, and studies have shown that an increased number of oncogenic alterations equates to an increased level of dedifferentiation and aggressiveness. The clinical management of ATC requires a multidisciplinary approach; according to recent American Thyroid Association guidelines, surgery, radiotherapy and/or chemotherapy should be considered. In addition to conventional therapies, novel molecular targeted therapies are the most promising emerging treatment modalities. These drugs are often multiple receptor tyrosine kinase inhibitors, several of which have been tested in clinical trials with encouraging results so far. Accordingly, clinical trials are ongoing to evaluate the safety, efficacy and effectiveness of these new agents. This Review describes the updated clinical and pathological features of ATC and provides insight into the molecular biology of this disease. The most recent literature regarding conventional, newly available and future therapies for ATC is also discussed.

The protective role of sphingosine-1-phosphate against the action of the vascular disrupting agent combretastatin A-4 3-O-phosphate

Solid tumours vary in sensitivity to the vascular disrupting agent combretastatin A-4 3-O-phosphate (CA4P), but underlying factors are poorly understood. The signaling sphingolipid, sphingosine-1-phosphate (S1P), promotes vascular barrier integrity by promoting assembly of VE-cadherin/β-catenin complexes. We tested the hypothesis that tumour pre-treatment with S1P would render tumours less susceptible to CA4P. S1P (1μM) pretreatment attenuated an increase in endothelial cell (HUVEC) monolayer permeability induced by 10μM CA4P. Intravenously administered S1P (8mg/kg/hr for 20 minutes then 2mg/kg/hr for 40 minutes), reduced CA4P-induced (30mg/kg) blood flow shut-down in fibrosarcoma tumours in SCID mice (n≥7 per group), as measured by tumour retention of an intravenously administered fluorescent lectin. A trend towards in vivo protection was also found using laser Doppler flowmetry. Immunohistochemical staining of tumours ex vivo revealed disrupted patterns of VE-cadherin in vasculature of mice treated with CA4P, which were decreased by pretreatment with S1P. S1P treatment also stabilized N-cadherin junctions between endothelial cells and smooth muscle cells in culture, and stabilized tubulin filaments in HUVEC monolayers. We conclude that the rapid shutdown of tumour microvasculature by CA4P is due in part to disruption of adherens junctions and that S1P has a protective effect on both adherens junctions and the endothelial cell cytoskeleton.

Micro-HCCs in rats with liver cirrhosis: paradoxical targeting effects with vascular disrupting agent CA4P

We sought to investigate anticancer efficacy of a vascular disrupting agent (VDA) combretastatin A-4 phosphate (CA4P) in relation to tumor size among hepatocellular carcinomas (HCCs) in rats using magnetic resonance imaging (MRI) and postmortem techniques. Nineteen rats with 43 chemically-induced HCCs of 2.8–20.9 mm in size on liver cirrhosis received CA4P intravenously at 10 mg/kg. Tumor-diameter was measured by T2-weighted imaging (T2WI) to define microcancers (< 5 mm) versus larger HCCs. Vascular responses and tissue necrosis were detected by diffusion-weighted imaging (DWI), contrast-enhanced T1-weighted imaging (CE-T1WI) and dynamic contrast enhanced (DCE-) MRI, which were validated by microangiography and histopathology. MRI revealed nearly complete necrosis in 5 out of 7 micro-HCCs, but diverse therapeutic necrosis in larger HCCs with a positive correlation with tumor size. Necrosis in micro-HCCs was 36.9% more than that in larger HCCs. While increased diffusion coefficient (ADC_diff) suggested tumor necrosis, perfusion coefficient (ADC_perf) indicated sharply decreased blood perfusion in cirrhotic liver together with a reduction in micro-HCCs. DCE revealed lowered tumor blood flow from intravascular into extravascular extracellular space (EES). Microangiography and histopathology revealed hypo- and hypervascularity in 4 and 3 micro-HCCs, massive, partial and minor degrees of tumoral necrosis in 5, 1 and 1 micro-HCCs respectively, and patchy necrotic foci in cirrhotic liver. CD34-PAS staining implicated that poorly vascularized micro-HCCs growing on liver cirrhosis tended to respond better to CA4P treatment. In this study, more complete CA4P-response occurred unexpectedly in micro-HCCs in rats, along with CA4P-induced necrotic foci in cirrhotic liver. These may help to plan clinical applications of VDAs in patients with HCCs and liver cirrhosis.

Novel treatment options for anaplastic thyroid cancer

Several genetic alterations have been identified in different molecular pathways ofanaplastic thyroid cancer (ATC) and associated with tumor aggressiveness and progression (BRAF, p53,RAS, EGFR, VEGFR-1, VEGFR-2, etc). New drugs targeting these molecular pathways have beenrecently evaluated in ATC. Areas covered: We review the new targeted therapies of ATC. Interesting results have been reported with molecules targeting different pathways, as: a-BRAF (dabrafenib/trametinib, vemurafenib); b-angiogenesis (sorafenib, combretastatin, vandetanib, sunitinib, lenvatinib, CLM3, etc); c-EGFR (gefitinib); d- PPARγ agonists (rosiglitazone, pioglitazone, efatutazone). In patients with ATC treated with lenvatinib, a median overall survival of 10.6 (3.8-19.8) months was reported. In order to bypass the resistance to the single drug, the capability of targeted drugs to synergize with radiation, or chemotherapy, or other targeted drugs is explored. Expert commentary: New, affordable and individual genomic analysis combined with the opportunity to test these new treatments in primary cell cultures from every ATC patient in vitro, may permit the personalization of therapy. Increasing the therapeutic effectiveness and avoiding the use of ineffective drugs. The identification of new treatments is necessary, to extend life duration guaranteing a good quality of life. To bypass the resistance to asingle drug, the capability of targeted drugs to synergize with radiation, or chemotherapy, or othertargeted drugs is explored. Moreover, new affordable individual genomic analysis and the opportunity totest these novel treatments in primary cell cultures from every ATC patient in vitro, might permit topersonalize the therapy, increasing the therapeutic effectiveness and avoiding the use of ineffectivedrugs.

A dose-escalation study of combretastatin A4-phosphate in healthy dogs

Combretastatin A4-Phosphate (CA4P) is a vascular disrupting agent revealing promising results in cancer treatments for humans. The aim of this study was to investigate the safety and adverse events of CA4P in healthy dogs as a prerequisite to application of CA4P in dogs with cancer. Ten healthy dogs were included. The effects of escalating doses of CA4P on physical, haematological and biochemical parameters, systolic arterial blood pressure, electrocardiogram, echocardiographic variables and general wellbeing were characterised. Three different doses were tested: 50, 75 and 100 mg m^-2 . At all 3 CA4P doses, nausea, abdominal discomfort as well as diarrhoea were observed for several hours following administration. Likewise, a low-grade neutropenia was observed in all dogs. Doses of 75 and 100 mg m^-2 additionally induced vomiting and elevation of serum cardiac troponine I levels. At 100 mg m^-2 , low-grade hypertension and high-grade neurotoxicity were also observed. In healthy dogs, doses up to 75 mg m^-2 seem to be well tolerated. The severity of the neurotoxicity observed at 100 mg m^-2 , although transient, does not invite to use this dose in canine oncology patients.

The Treatment of Advanced Thyroid Cancer in the Age of Novel Targeted Therapies

Until recently, patients with advanced thyroid cancers had limited options for systemic treatment. With the introduction of tyrosine kinase inhibitors (TKIs) as a promising new class of targeted therapies for thyroid cancer, suddenly patients with advanced disease were given new options to extend survival. Guidelines worldwide have been updated to include general indications for these newer agents, but questions remain regarding which agent(s) to select, when to begin treatment, and how long therapy should continue. Additionally, the true impact of TKIs on overall survival and quality-of-life in thyroid cancer patients needs further clarification. As familiarity with approved agents and longer-term data become available, better strategies for implementation of these targeted drugs will evolve to optimize benefit for patients living with metastatic disease.

Facilitating anaplastic thyroid cancer specialized treatment: A model for improving access to multidisciplinary care for patients with anaplastic thyroid cancer

BACKGROUND

Anaplastic thyroid cancer (ATC) is a highly aggressive thyroid cancer. Several treatment trials are available, but the number of eligible patients to participate is very low because of the rarity and aggressiveness of the disease.

METHODS

Facilitating Anaplastic Thyroid Cancer Specialized Treatment (FAST) is a quality improvement project aimed at decreasing time from referral to disposition (scheduling of first appointment) to our institution. After identifying reasons for delays, we created a new process flow specifically for patients with ATC allowing patients to be scheduled immediately.

RESULTS

Historical data revealed a mean referral to disposition time for patients with ATC of 8.7 days before our intervention. After the intervention, the mean referral to disposition time was reduced to 0.5 days. Participation in treatment trials for all patients with ATC was 34%.

CONCLUSION

Since the implementation of FAST, the access time has decreased and the number of successful referrals for ATC has increased significantly.

Lenvatinib for Anaplastic Thyroid Cancer

BACKGROUND

Lenvatinib has been approved by regulatory agencies in Japan, the United States, and the European Union for treatment of radioiodine-refractory differentiated thyroid cancer (RR-DTC). Thyroid cancer, however, is a clinically diverse disease that includes anaplastic thyroid cancer (ATC), the subtype associated with the highest lethality. Effective therapy for ATC is an unmet need.

PATIENTS AND METHODS

This phase 2, single-arm, open-label study in patients with thyroid cancer, including ATC, RR-DTC, and medullary thyroid cancer was conducted from 3 September 2012 to 9 July 2015. Patients received lenvatinib 24 mg daily until disease progression or development of unacceptable toxicity. The primary endpoint was safety, and the secondary endpoint was efficacy, as assessed by progression-free survival (PFS), overall survival (OS), and objective response rate.

RESULTS

At data cutoff, 17 patients with ATC were enrolled. All experienced ≥1 treatment-emergent adverse event (TEAE). The most frequent TEAEs were decreased appetite (82%), hypertension (82%), fatigue (59%), nausea (59%), and proteinuria (59%). Of note, only one patient required lenvatinib withdrawal because of a TEAE, and this TEAE was considered unrelated to lenvatinib. The median PFS was 7.4 months [95% confidence interval (CI): 1.7-12.9], the median OS was 10.6 months (95% CI: 3.8-19.8), and the objective response rate was 24%.

CONCLUSION

In this study, lenvatinib demonstrated manageable toxicities with dose adjustments and clinical activity in patients with ATC. This clinical activity of lenvatinib warrants further investigation in ATC.

CLINICALTRIALSGOV

NCT01728623.

Anaplastic thyroid carcinoma and foscarnet use in a multitarget treatment documented by 18F-FDG PET/CT: A case report

RATIONALE

The case reported the rapid remission of disease recurrence achieved adding foscarnet, a DNA polymerase inhibitor that interacts with fibroblast growth factor 2, to low molecular weight heparin and sunitinib for the first time in a patient with an anaplastic thyroid cancer (ATC).

PATIENT CONCERNS

A 65-year-old woman with a multinodular goiter referred for a rapid enlargement of a nodule. Histological examination revealed an ATC with a little area of papillary thyroid cancer (PTC). The patient was resistant to selective single-target treatment.

DIAGNOSES

Immunophenotyping and gene analyses found a significant increase in FGF2 and FGFR1 expression in the primary ATC area (FGF2 = 38.2 ± 6.2% in ATC vs 34.6 ± 6.0% in the differentiated area of PTC, P < 0.05; FGFR1: 41.7 ± 6.0% in ATC vs 34.4 ± 4.2% in PTC, P < 0.001) and in metastatic neck lymph nodes (P < 0.001 vs normal control tissues). Unlike conventional imaging, F-FDG PET/CT with PERCIST 1.0 criteria promptly and quantitatively detected disease recurrence and remission before and after multitarget therapy, combining anatomic, metabolic, and functional data.

INTERVENTIONS

Foscarnet was administered given the positivity for FGF2, FGFR1 and FGFR4 in ATC. Low molecular wight heparin and Sunitinib were coadministere to limiti metastatic progression and on neck tumor masse, respectively.

OUTCOMES

The rationale for the clinical response to this innovative multitarget association with foscarnet is based on the histological and genetic finding that fibroblast growth factors and their receptor super-family are up-regulated in the primary anaplastic thyroid tumor and in the metastatic lymph node of our patient.

LESSONS

We propose that fibroblast growth factors and their receptor super-family play a key role as potential therapeutic targets in anaplastic thyroid cancer and the positive relevance of this suggestion for patient care, especially for an individualized management.

Clinical presentation, treatment and outcome of anaplastic thyroid carcinoma: results of a multicenter study in Germany

CONTEXT

Anaplastic thyroid carcinoma (ATC) is an orphan disease and confers a dismal prognosis. Standard treatment is not established.

OBJECTIVE

The aim of this study is to describe clinical characteristics, current treatment regimens and outcome of ATC and to identify clinical prognostic markers and treatment factors associated with improved prognosis.

DESIGN

Retrospective cohort study at five German tertiary care centers.

PATIENTS AND METHODS

Totally 100 ATC patients diagnosed between 2000 and 2015 were included in the analysis. Disease-specific overall survival (OS) was compared with the Kaplan-Meier method and log-rank test; Cox proportional hazard model was used to identify risk factors.

RESULTS

The 6-month, 1-year and 5-year disease-specific OS rates were 37, 28 and 5%, respectively. Stage-dependent OS at 6 months was 78, 54 and 18% for stage IVA, B and C, respectively. 29% patients survived >1 year. Multivariate analysis of OS identified age ≥70 years, incomplete local resection status and the presence of distant metastasis as significant risk factors associated with shorter survival. Radical surgery (hazard ratio [HR] 2.20, 95% confidence interval (CI) 1.19-4.09, P = 0.012), external beam radiation therapy (EBRT) ≥40 Gy (HR = 0.34, 0.15-0.76, P = 0.008) and any kind of chemotherapy (CTX) (HR = 11.64, 2.42-60.39, P = 0.003) were associated with longer survival in multivariate analyses adjusted for age and tumor stage. A multimodal treatment regimen was significantly associated with a survival benefit (HR = 1.04, 1.01-1.08, P < 0.0001) only in IVC patients.

CONCLUSION

Disease-specific OS is still poor in ATC. Treatment factors associated with improved OS provide a rationale to devise treatment pathways for routine care. Collaborative research structures should be aimed to advance treatment of ATC.

A randomized Phase II trial of the tumor vascular disrupting agent CA4P (fosbretabulin tromethamine) with carboplatin, paclitaxel, and bevacizumab in advanced nonsquamous non-small-cell lung cancer

Introduction

Combretastatin A4-phosphate, fosbretabulin tromethamine (CA4P) is a vascular disrupting agent that targets tumor vasculature. This study evaluated the safety of CA4P when combined with carboplatin, paclitaxel, and bevacizumab in chemotherapy-naïve subjects with advanced nonsquamous, non-small-cell lung cancer.

Methods

Adult subjects with confirmed American Joint Committee on Cancer six stage IIIB/IV non-small-cell lung cancer and an Eastern Cooperative Oncology Group performance score of 0 or 1 were randomized to receive six cycles (treatment phase) of paclitaxel (200 mg/m²), carboplatin (area under the concentration versus time curve 6), and bevacizumab (15 mg/kg) on day 1 and repeated every 21 days, or this regimen plus CA4P (60 mg/m²) on days 7, 14, and 21 of each cycle. Subjects could then receive additional maintenance treatment (excluding carboplatin and paclitaxel) for up to 1 year.

Results

Sixty-three subjects were randomized, 31 to control and 32 to CA4P, and 19 (61.3%) and 17 (53.1%), respectively, completed the treatment phase. Exposure to study treatment and dose modifications were comparable between the randomized groups. The overall incidence of treatment-emergent adverse events was similar between groups, with increased neutropenia, leukopenia, and hypertension in the CA4P group. Deaths, serious adverse events, and early discontinuations from treatment were comparable between the randomized treatment groups. The overall tumor response rate with CA4P was 50% versus 32% in controls. Overall and progression-free survival rates were comparable between the groups.

Conclusion

CA4P plus carboplatin, paclitaxel, and bevacizumab appears to be a tolerable regimen with an acceptable toxicity profile in subjects with advanced non-small-cell lung cancer.

The Safety and Efficacy of Weekly Paclitaxel Administration for Anaplastic Thyroid Cancer Patients: A Nationwide Prospective Study

BACKGROUND

Anaplastic thyroid cancer (ATC) is a rare and extremely aggressive malignancy, with a median survival of less than 6 months due to rapid progression and resistance to multimodal therapies. Effective treatment strategies have not been identified. A prospective clinical study was performed to objectively evaluate outcomes of treatment with paclitaxel.

METHODS

An investigator-initiated, multicenter, nonrandomized, open-label, single-arm study to evaluate the feasibility and efficacy of weekly paclitaxel (80 mg/m(2)) administration for patients with pathologically confirmed ATC was conducted in a nationwide organization.

RESULTS

Feasibility was analyzed in 56 patients. More than one course of treatment was performed in 52 (93%) patients retaining sufficient dose intensity (>84%). No patient had to terminate the treatment because of an adverse event. The median overall survival was 6.7 months [confidence interval 4.4-9.0]. The 6-month survival was 54%. Among the 42 patients with an evaluable lesion, none demonstrated complete remission, 9 (21%) showed partial remission, 22 (52%) achieved stable disease, and 8 (19%) exhibited progressive disease; 3 did not complete the initial treatment course. The objective response rate was 21%, and the clinical benefit rate was 73%. The median time to progression was 1.6 months. Statistically, no additional effect of concomitant radiation was demonstrated in 6 patients receiving combined therapy. Eight patients, in whom a complete post-treatment surgical removal of the tumor was feasible, survived significantly longer (median 7.6 months [CI 8.1-23.0]) than the other 34 patients in whom the tumor could not be completely removed after chemotherapy (5.4 months [CI 3.0-7.8], p = 0.018).

SUMMARY

The study demonstrates objective and accurate information concerning the feasibility and efficacy of a standardized treatment with weekly paclitaxel administration for ATC patients.

CONCLUSIONS

Weekly paclitaxel administration for ATC patients can be of clinical benefit in a neo-adjuvant setting.

Molecular diagnostics and anaplastic thyroid carcinoma: the time has come to harvest the high hanging fruit

Targeted therapies have played a major role in cancer therapeutics, starting with the discovery of a drug against BCR–ABL rearrangements in chronic myelogenous leukemia. This led to the first approval of a targeted agent in cancer and since, many others have followed. Anaplastic thyroid cancer (ATC) is an aggressive carcinoma with few curative options. Although previous cytotoxic chemotherapy and kinase inhibitor therapies have not proven efficacious in ATC, some of the newer drugs appear to be promising. A case report and a comprehensive review of the current standard of care, genetics, modern therapeutic drugs and clinical trials are presented, in order to outline where we currently stand and where the future lies in the quest for a cure for ATC.

Anaplastic Thyroid Carcinoma: Treatment in the Age of Molecular Targeted Therapy

Anaplastic thyroid carcinoma is one of the most aggressive and deadly cancers in humans and accounts for one to two cases per million persons annually. The rarity of this malignancy and the rapidity by which it grows has been a major barrier to progress in finding effective therapies. Thus, the treatment that is the current standard of care for these patients is largely palliative, and few are cured; however, novel therapies and approaches are being studied in patients with anaplastic thyroid carcinoma and are delineated herein.

Spanish consensus for the management of patients with anaplastic cell thyroid carcinoma

Anaplastic thyroid cancer (ATC) is the most aggressive solid tumor and almost uniformly lethal in humans. The Boards of the Thyroid Cancer Group of the Spanish Society of Endocrinology and Nutrition and the Grupo Español de Enfermedades Huérfanas e Infrecuentes of the Spanish Society of Oncology requested that an independent task force draft a more comprehensive consensus statement regarding ATC. All relevant literature was reviewed, including serial PubMed searches together with additional articles. This is the first, comprehensive Spanish consensus statement for ATC and includes the characteristics, diagnosis, initial evaluation, treatment goals, recommendations and modalities for locoregional and advanced disease, palliative care options, surveillance, and long-term monitoring. Newer systemic therapies are being investigated, but more effective combinations are needed to improve patient outcomes. Though more aggressive radiotherapy has reduced locoregional recurrences, median overall survival has not improved in more than 50 years.

Treatment of advanced thyroid cancer with targeted therapies: ten years of experience

Thyroid cancer is rare, but it is the most frequent endocrine malignancy. Its prognosis is generally favorable, especially in cases of well-differentiated thyroid cancers (DTCs), such as papillary and follicular cancers, which have survival rates of approximately 95% at 40 years. However, 15-20% of cases became radioiodine refractory (RAI-R), and until now, no other treatments have been effective. The same problems are found in cases of poorly differentiated (PDTC) and anaplastic (ATC) thyroid cancers and in at least 30% of medullary thyroid cancer (MTC) cases, which are very aggressive and not sensitive to radioiodine. Tyrosine kinase inhibitors (TKIs) represent a new approach to the treatment of advanced cases of RAI-R DTC, MTC, PDTC, and, possibly, ATC. In the past 10 years, several TKIs have been tested for the treatment of advanced, progressive, and RAI-R thyroid tumors, and some of them have been recently approved for use in clinical practice: sorafenib and lenvatinib for DTC and PDTC and vandetanib and cabozantinib for MTC. The objective of this review is to present the current status of the treatment of advanced thyroid cancer with the use of innovative targeted therapies by describing both the benefits and the limits of their use based on the experiences reported so far. A comprehensive analysis and description of the molecular basis of these therapies, as well as new therapeutic perspectives, are reported. Some practical suggestions are given for both the choice of patients to be treated and their management, with particular regard to the potential side effects.

Dual inhibition of HDAC and EGFR signaling with CUDC-101 induces potent suppression of tumor growth and metastasis in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the most lethal human malignancies that currently has no effective therapy. We performed quantitative high-throughput screening (qHTS) in three ATC cell lines using 3,282 clinically approved drugs and drug candidates, and identified 100 active agents. Enrichment analysis of active compounds showed that inhibitors of EGFR and histone deacetylase (HDAC) were most active. Of these, the first-in-class dual inhibitor of EGFR, HER2 and HDACs, CUDC-101, had the highest efficacy and lower IC₅₀ than established drugs. We validated that CUDC-101 inhibited cellular proliferation and resulted in cell death by inducing cell cycle arrest and caspase-dependent apoptosis. CUDC-101 also inhibited cellular migration in vitro. Mechanistically, CUDC-101 inhibited MAPK signaling and histone deacetylation in ATC cell lines with multiple driver mutations present in human ATC. The anticancer effect of CUDC-101 was associated with increased expression of p21 and E-cadherin, and reduced expression of survivin, XIAP, β-catenin, N-cadherin, and Vimentin. In an in vivo mouse model of metastatic ATC, CUDC-101 inhibited tumor growth and metastases, and significantly prolonged survival. Response to CUDC-101 treatment in vivo was associated with increased histone 3 acetylation and reduced survivin expression. Our findings provide a preclinical basis to evaluate CUDC-101 therapy in ATC.

Evolving molecularly targeted therapies for advanced-stage thyroid cancers

Increased understanding of disease-specific molecular targets of therapy has led to the regulatory approval of two drugs (vandetanib and cabozantinib) for the treatment of medullary thyroid cancer (MTC), and two agents (sorafenib and lenvatinib) for the treatment of radioactive- iodine refractory differentiated thyroid cancer (DTC) in both the USA and in the EU. The effects of these and other therapies on overall survival and quality of life among patients with thyroid cancer, however, remain to be more-clearly defined. When applied early in the disease course, intensive multimodality therapy seems to improve the survival outcomes of patients with anaplastic thyroid cancer (ATC), but salvage therapies for ATC are of uncertain benefit. Additional innovative, rationally designed therapeutic strategies are under active development both for patients with DTC and for patients with ATC, with multiple phase II and phase III randomized clinical trials currently ongoing. Continued effort is being made to identify further signalling pathways with potential therapeutic relevance in thyroid cancers, as well as to elaborate on the complex interactions between signalling pathways, with the intention of translating these discoveries into effective and personalized therapies. Herein, we summarize the progress made in molecular medicine for advanced-stage thyroid cancers of different histotypes, analyse how these developments have altered - and might further refine - patient care, and identify open questions for future research.

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.

Valproic Acid, a Histone Deacetylase Inhibitor, in Combination with Paclitaxel for Anaplastic Thyroid Cancer: Results of a Multicenter Randomized Controlled Phase II/III Trial

Anaplastic thyroid cancer (ATC) has a median survival less than 5 months and, to date, no effective therapy exists. Taxanes have recently been stated as the main drug treatment for ATC, and the histone deacetylase inhibitor valproic acid efficiently potentiates the effects of paclitaxel in vitro. Based on these data, this trial assessed the efficacy and safety of the combination of paclitaxel and valproic acid for the treatment of ATC. This was a randomized, controlled phase II/III trial, performed on 25 ATC patients across 5 centers in northwest Italy. The experimental arm received the combination of paclitaxel (80 mg/m²/weekly) and valproic acid (1,000 mg/day); the control arm received paclitaxel alone. Overall survival and disease progression, evaluated in terms of progression-free survival, were the primary outcomes. The secondary outcome was the pharmacokinetics of paclitaxel. The coadministration of valproic acid did not influence the pharmacokinetics of paclitaxel. Neither median survival nor median time to progression was statistically different in the two arms. Median survival of operated-on patients was significantly better than that of patients who were not operated on. The present trial demonstrates that the addition of valproic acid to paclitaxel has no effect on overall survival and disease progression of ATC patients. This trial is registered with EudraCT 2008-005221-11.

The genomic and transcriptomic landscape of anaplastic thyroid cancer: implications for therapy

BACKGROUND

Anaplastic thyroid carcinoma is the most undifferentiated form of thyroid cancer and one of the deadliest of all adult solid malignancies. Here we report the first genomic and transcriptomic profile of anaplastic thyroid cancer including those of several unique cell lines and outline novel potential drivers of malignancy and targets of therapy.

METHODS

We describe whole genomic and transcriptomic profiles of 1 primary anaplastic thyroid tumor and 3 authenticated cell lines. Those profiles augmented by the transcriptomes of 4 additional and unique cell lines were compared to 58 pairs of papillary thyroid carcinoma and matched normal tissue transcriptomes from The Cancer Genome Atlas study.

RESULTS

The most prevalent mutations were those of TP53 and BRAF; repeated alterations of the epigenetic machinery such as frame-shift deletions of HDAC10 and EP300, loss of SMARCA2 and fusions of MECP2, BCL11A and SS18 were observed. Sequence data displayed aneuploidy and large regions of copy loss and gain in all genomes. Common regions of gain were however evident encompassing chromosomes 5p and 20q. We found novel anaplastic gene fusions including MKRN1-BRAF, FGFR2-OGDH and SS18-SLC5A11, all expressed in-frame fusions involving a known proto-oncogene. Comparison of the anaplastic thyroid cancer expression datasets with the papillary thyroid cancer and normal thyroid tissue transcriptomes suggested several known drug targets such as FGFRs, VEGFRs, KIT and RET to have lower expression levels in anaplastic specimens compared with both papillary thyroid cancers and normal tissues, confirming the observed lack of response to therapies targeting these pathways. Further integrative data analysis identified the mTOR signaling pathway as a potential therapeutic target in this disease.

CONCLUSIONS

Anaplastic thyroid carcinoma possessed heterogeneous and unique profiles revealing the significance of detailed molecular profiling of individual tumors and the treatment of each as a unique entity; the cell line sequence data promises to facilitate the more accurate and intentional drug screening studies for anaplastic thyroid cancer.

Natural Products as a Vital Source for the Discovery of Cancer Chemotherapeutic and Chemopreventive Agents

Throughout history, natural products have played a dominant role in the treatment of human ailments. For example, the legendary discovery of penicillin transformed global existence. Presently, natural products comprise a large portion of current-day pharmaceutical agents, most notably in the area of cancer therapy. Examples include Taxol, vinblastine, and camptothecin. These structurally unique agents function by novel mechanisms of action; isolation from natural sources is the only plausible method that could have led to their discovery. In addition to terrestrial plants as sources for starting materials, the marine environment (e.g., ecteinascidin 743, halichondrin B, and dolastatins), microbes (e.g., bleomycin, doxorubicin, and staurosporin), and slime molds (e.g., epothilone B) have yielded remarkable cancer chemotherapeutic agents. Irrespective of these advances, cancer remains a leading cause of death worldwide. Undoubtedly, the prevention of human cancer is highly preferable to treatment. Cancer chemoprevention, the use of vaccines or pharmaceutical agents to inhibit, retard, or reverse the process of carcinogenesis, is another important approach for easing this formidable public health burden. Similar to cancer chemotherapeutic agents, natural products play an important role in this field. There are many examples, including dietary phytochemicals such as sulforaphane and phenethyl isothiocyanate (cruciferous vegetables) and resveratrol (grapes and grape products). Overall, natural product research is a powerful approach for discovering biologically active compounds with unique structures and mechanisms of action. Given the unfathomable diversity of nature, it is reasonable to suggest that chemical leads can be generated that are capable of interacting with most or possibly all therapeutic targets.

[Differentiated thyroid cancer]

Thyroid carcinoma is a rare and heterogeneous disease. Initial therapy and follow-up has to be adjusted to the individual risk for an excellent vs. poor prognosis. Differentiated thyroid cancer has a very high cure rate and is treated by surgery, usually followed by radioiodine ablation. Depending on the response to initial therapy the risk for persisting or recurrent disease should be re-evaluated. Continued TSH suppressive levothyroxine therapy is only recommended in high-risk patients. In contrast, metastatic radioiodine-refractory thyroid cancers have a poor prognosis and may benefit from multidisciplinary treatment concepts including tyrosine kinase inhibitors. Due to its complexity, management of thyroid cancer patients should be performed in close collaboration with a specialized thyroid cancer team.

Anaplastic thyroid cancer

PURPOSE OF REVIEW

Anaplastic thyroid cancer (ATC) is a rare malignancy of the thyroid with a high mortality rate. Conventional therapy has not been effective. Several biological agents are being investigated. The purpose of the review is to highlight the current standards for treatment and review new targets for treating ATC.

RECENT FINDINGS

Retrospective studies have led to formulation of guidelines for management, including those by the American Thyroid Association. An expansion in the understanding of the genetic mutations has led to several newer biological agents being tested to treat ATC. Aurora kinase inhibitors, PPAR γ agonists, and vascular targeting agents are some of the latest therapeutic agents that have shown promise and could become standard of therapy with further supporting research.

SUMMARY

Further well coordinated preclinical and clinical research is needed to support the emerging treatments for ATC.

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.

Stabilizing versus destabilizing the microtubules: a double-edge sword for an effective cancer treatment option?

Microtubules are dynamic and structural cellular components involved in several cell functions, including cell shape, motility, and intracellular trafficking. In proliferating cells, they are essential components in the division process through the formation of the mitotic spindle. As a result of these functions, tubulin and microtubules are targets for anticancer agents. Microtubule-targeting agents can be divided into two groups: microtubule-stabilizing, and microtubule-destabilizing agents. The former bind to the tubulin polymer and stabilize microtubules, while the latter bind to the tubulin dimers and destabilize microtubules. Alteration of tubulin-microtubule equilibrium determines the disruption of the mitotic spindle, halting the cell cycle at the metaphase-anaphase transition and, eventually, resulting in cell death. Clinical application of earlier microtubule inhibitors, however, unfortunately showed several limits, such as neurological and bone marrow toxicity and the emergence of drug-resistant tumor cells. Here we review several natural and synthetic microtubule-targeting agents, which showed antitumor activity and increased efficacy in comparison to traditional drugs in various preclinical and clinical studies. Cryptophycins, combretastatins, ombrabulin, soblidotin, D-24851, epothilones and discodermolide were used in clinical trials. Some of them showed antiangiogenic and antivascular activity and others showed the ability to overcome multidrug resistance, supporting their possible use in chemotherapy.

Anaplastic Thyroid Carcinoma, Version 2.2015

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Thyroid Carcinoma focuses on anaplastic carcinoma because substantial changes were made to the systemic therapy recommendations for the 2015 update. Dosages and frequency of administration are now provided, docetaxel/doxorubicin regimens were added, and single-agent cisplatin was deleted because it is not recommended for patients with advanced or metastatic anaplastic thyroid cancer.

The treatment landscape in thyroid cancer: a focus on cabozantinib

Although patients with thyroid cancer generally fare well, there is a subset for which this is not necessarily true. Progress in understanding the molecular aberrations in thyroid cancer has led to a change in the management of these cases. Since 2011, four multikinase inhibitors (MKIs) have been approved by the US Food and Drug Administration for thyroid cancer – cabozantinib and vandetanib for medullary thyroid cancer and sorafenib and lenvatinib for differentiated thyroid cancer. This change in the treatment landscape has raised challenges for practitioners who may not be familiar with the use of MKIs or with the treatment and natural history of advanced thyroid cancer in general. This article reviews the epidemiology, molecular drivers, and initial treatment of patients with thyroid cancer and offers practical guidance to assist with the determination of when to appropriately start an MKI. As an example, cabozantinib and its efficacy are discussed in detail. Close monitoring is required for all patients on targeted agents to assess for adverse effects and response to therapy. An approach to managing drug-related adverse events is detailed. Since these drugs are not curative and have not yet proven to prolong overall survival, it is critical to weigh the risks and benefits of treatment at every visit. The potential value of changing to a different agent following failure of an MKI is also addressed.

Fosbretabulin for the treatment of anaplastic thyroid cancer

Fosbretabulin tromethamine is a vascular disrupting agent, which is a type of drug that is designed to damage the vasculature (blood vessels) of cancer tumors, causing central necrosis. This drug showed activity against anaplastic thyroid cancer that was demonstrated in orthotopic xenograft models as well as in Phase I/II trials with or without carboplatin and paclitaxel combination therapy. In all of these studies, fosbretabulin was well tolerated.

Concept and design of a nationwide prospective feasibility/efficacy/safety study of weekly paclitaxel for patients with pathologically confirmed anaplastic thyroid cancer (ATCCJ-PTX-P2)

Background

Anaplastic thyroid cancer (ATC) is one of the most aggressive malignancies in humans, often demonstrating resistance to multimodal therapeutic approaches. The median survival of ATC patients after initial diagnosis was reported to be < 6 months due to the rapid progression of disease by dissemination and/or invasion. There have been several reports describing possible effective chemotherapies, but these studies might be biased by the nature of retrospective accumulations of clinical experiences, and thus reliable data concerning the efficacies of the treatment efforts are required.

Design

In 2009, we established the research organization Anaplastic Carcinoma Research Consortium Japan (ATCCJ) to investigate this highly malignant disease. Using this nationwide organization, we conducted a prospective clinical study to investigate the feasibility, safeness, and efficacy of chemotherapy with weekly paclitaxel for ATC patients. This trial is registered on the clinical trials site of the University Hospital Medical Information Network Clinical Trials Registry Web site (UMIN000008574). The study was started in 2012, and enrollment was closed in March 2014 after accumulating 71 patients from 28 registered institutes. The follow-up data will be available in April 2015.

Discussion

Important information concerning the management of this disease is expected to be revealed by this study. The concept and design of the study are described herein.

Combretastatin A4-phosphate and its potential in veterinary oncology: a review

For many years, research on anticancer therapy has focussed almost exclusively on targeting cancer cells directly, to selectively kill them or restrict their growth. But limited advances in this strategy have led researchers to shift their attention to other potential targets. Active research is now on-going on targeting tumour stroma. Vascular disrupting agents (VDAs) appear a promising class of anticancer drugs that are currently under investigation as a sole or combined therapy in human cancer patients. This article will briefly touch on the history and biology of combretastatin A4-phosphate (CA4P) as a typical example of VDAs and will concentrate on the side effects that can be expected when used in veterinary patients. Particularly, the pathogenesis of these side effects and how they may be prevented and/or treated will be discussed. The purpose of this article is to illustrate the potentials of CA4P as anticancer therapy in veterinary oncology patients.

Tyrosine kinase inhibitors for the therapy of anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is often incurable so new therapeutic approaches are needed. Tyrosine kinases inhibitors (such as imanitib, sunitinib or sorafenib) are under evaluation for the treatment of ATC. Other vascular disrupting agents, such as combretastatin A4 phosphate, and antiangiogenic agents, such as aplidin, PTK787/ZK222584 and human VEGF monoclonal antibodies (bevacizumab, cetuximab), have been evaluated. Small-molecule adenosine triphosphate competitive inhibitors directed intracellularly at EGFRs tyrosine kinase, such as erlotinib or gefitinib, are also studied. Furthermore, new molecules have been shown to be active against ATC, such as CLM94 and CLM3. However, more research is needed to finally identify therapies able to control and to cure this disease.

Management of anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is a deadly disease with a dismal prognosis. Molecular analyses of ATC tumors have yielded interesting results, which could help in understanding the underlying mechanisms of this aggressive disease process. Managing ATC can be challenging and includes rapid diagnosis, adequate staging, and interdisciplinary, multimodal treatments to optimize patient outcome. Treatments include surgical resection to gross negative margins when possible, as well as neo- or adjuvant treatment with chemotherapy or external beam radiation (XRT) for locoregional disease. New treatment strategies include evaluating the benefits of vascular disrupting agents and tyrosine kinase inhibitors for advanced ATC with driver mutations, which can be targeted. This review summarizes key concepts in managing ATC.

Treatment of advanced thyroid cancer: role of molecularly targeted therapies

Advanced thyroid cancer is not amenable to therapy with conventional cytotoxic chemotherapy. However, newer advances in the understanding of the molecular pathogenesis of different subtypes of thyroid cancer have provided new opportunities for the evaluation of molecularly targeted therapies. This has led to multiple clinical trials using various multi-kinase inhibitors and the subsequent US FDA approval of sorafenib for differentiated thyroid cancer and vandetanib and cabozantinib for medullary thyroid carcinoma. This review provides a summary of the current literature for the treatment of advanced thyroid carcinoma and future directions in this disease.