Sorafenib in the treatment of radioiodine-refractory differentiated thyroid cancer: a meta-analysis

Therapeutic efficacy of sorafenib and plant-derived phytochemicals in human colorectal cancer cells

BACKGROUND

The present study aimed to investigate the sequence-dependent anticancer effects of combined treatment with sorafenib (Sora), a Food and Drug Administration-approved multikinase inhibitor drug, and plant-derived phytochemicals (PPCs) on human colorectal cancer (CRC) cell growth, and proteins associated with the control of cell cycle and apoptosis.

METHODS

The cytotoxic effects of 14 PPCs on CRL1554 fibroblast cells were determined using an MTT assay. Moreover, the cytotoxicity of Sora, PPCs, and a combination of both on CRC cells were also investigated. Cell cycle analysis was performed using flow cytometry, and cell apoptosis was investigated using DNA fragmentation, Annexin V/propidium iodide double staining, and mitochondrial membrane potential analyses. The cell cycle- and apoptosis-associated protein expression levels were analysed using western blotting.

RESULTS

Based on their low levels of cytotoxicity in CRL1554 cells at ≤ 20%, curcumin, quercetin, kaempferol, and resveratrol were selected for use in subsequent experiments. The combined treatment of sora and PPCs caused levels of CRC cytotoxicity in a dose-, cell type-, and schedule-dependent manner. Moreover, the combined treatment of CRC cells arrested cell growth at the S and G2/M phases, induced apoptotic cell death, caused extensive mitochondrial membrane damage, and altered the expression of the cell cycle and apoptotic proteins.

CONCLUSIONS

Results of the present study highlighted a difference in the level of sora efficacy in CRC cells when combined with PPCs. Further in vivo and clinical studies using the combined treatment of sora and PPCs are required to determine their potential as a novel therapeutic strategy for CRCs.

Surufatinib in Chinese Patients with Locally Advanced or Metastatic Differentiated Thyroid Cancer and Medullary Thyroid Cancer: A Multicenter, Open-Label, Phase II Trial

Background: Thyroid cancer is the most common endocrine tumor with an increasing incidence. Limited treatment options are available for patients with advanced or recurrent metastatic disease, resulting in a poor prognosis. Surufatinib targets multiple kinases (vascular endothelial growth factor receptors, fibroblast growth factor receptor-1, and colony-stimulating factor-1 receptor) involved in tumor angiogenesis and tumor immune evasion. Surufatinib has demonstrated promising antitumor activity in various advanced solid tumors. This study aimed to determine the objective response rate (ORR) of surufatinib in patients with locally advanced or distant metastatic differentiated thyroid cancer (DTC) or medullary thyroid cancer (MTC). Methods: This Phase II open-label study by Simon's two-stage design was conducted at 10 sites across China. Patients with radioiodine (RAI)-refractory DTC with locally advanced disease or distant metastasis (DTC1 group); patients who received limited initial surgery and then developed locally advanced unresectable recurrences and were not considered candidates for RAI therapy due to residual normal thyroid tissue (DTC2 group); or patients with MTC with locally advanced disease or distant metastasis (MTC group) were enrolled. A total of 59 patients were enrolled (26 in DTC1, 6 in DTC2, and 27 in MTC) and received 300 mg surufatinib daily in 28-day cycles. The primary endpoint was ORR as determined by the investigators. Results: Overall ORR was 23.2% [95% confidence interval, CI 12.98-36.42]: 21.7% in the DTC1 cohort, 33.3% in the DTC2 cohort, and 22.2% in the MTC cohort. Forty-nine patients achieved disease control (87.5% [CI 75.93-94.82]): 87.0% in the DTC1 cohort, 83.3% in the DTC2 cohort, and 88.9% in the MTC cohort. Median time to response was 59.0 days, and 59.0, 85.5, and 59.0 days in the DTC1, DTC2, and MTC cohorts. Overall median progression-free survival was 11.1 months [CI 5.98-16.69]; 11.1 months in DTC1 and MTC cohorts, while the DTC2 cohort had not reached the median at the data cutoff. The most common treatment-emergent adverse events grade ≥3 were hypertension (20.3%), proteinuria (11.9%), and then elevated blood pressure, hypertriglyceridemia, and pulmonary inflammation (5.1% each). Conclusions: Surufatinib demonstrated promising efficacy with a tolerable and manageable safety profile for patients with locally advanced or metastatic MTC, RAI-refractory DTC, or locally advanced unresectable recurrences unable to receive RAI.

Sorafenib and radioiodine-refractory differentiated thyroid cancer (RR-DTC): a systematic review and meta-analysis

BACKGROUND

Except conventional treatments, research on medical approach for radioiodine-refractory differentiated thyroid cancer (RR-DTC) was considered particularly challenging. Sorafenib, a novel biological agent, has been widely studied in the treatment of RR-DTC for years. We performed a systematic review and meta-analysis to explore the efficiency and safety of treating RR-DTC patients with sorafenib.

METHODS

An electronic search on PubMed/Medline and Embase was carried out to search associated articles. Fixed-effects or random-effects models were chose according to the heterogeneity.

RESULTS

A total of 15 eligible studies (636 patients) were included. As shown by the only randomised clinical trial-DECISION, sorafenib significantly improved progression-free survival (PFS) compared with placebo in patients with progressive RR-DTC. The pooled analysis indicated that there were 26% patients (95% CI: 0.19-0.34) achieved partial response (PR), and 44% patients (98% CI: 0.39-0.48) achieved stable disease (SD). The most frequent adverse effects (AEs) observed included hand-foot syndrome (HFS), diarrhoea, fatigue, alopecia, weight loss (WS) and rash, the incidence of all grades AEs for which were 71%, 60%, 59%, 55%, 51% and 50%, respectively. There were 68% patients (252/368), who had a dose reduction because of the drug toxicities and AEs.

CONCLUSIONS

Sorafenib could improve PFS in patients with progressive RR-DTC, comparing with placebo. Due to the resistance to conventional treatments, sorafenib is considered as a promising treatment for RR-DTC by most physicians specialised in this field. However, the use of sorafenib should be cautious due to a high incidence of AEs caused by the agent. More effective agents with less toxicities are warranted.

Clinicopathological Features Predict Outcomes in Patients with Radioiodine-Refractory Differentiated Thyroid Cancer Treated with Sorafenib: A Real-World Study

BACKGROUND

Because beneficial response and progression-free survival (PFS) were achieved by well-designed clinical trials with tyrosine kinase inhibitors (TKIs) in patients with progressive radioiodine-refractory differentiated thyroid cancer (RR-DTC), the overall survival (OS) and improvement of therapeutic outcomes in the real world have been anticipated.

SUBJECTS, MATERIALS, AND METHODS

This prospective, single-center, real-world study assessed the predictive significance of clinicopathological features on disease control rate (DCR), objective response rate (ORR), PFS, and OS in a cohort of 72 patients with progressive RR-DTC treated with sorafenib at an initial dose of 200 mg twice daily.

RESULTS

Disease control, objective response, and biochemical effectiveness were achieved in 73.3%, 21.7%, and 77.9% of patients, respectively. The median PFS and OS were 17.6 and 28.9 months, respectively. Multivariate analyses showed that hand-foot syndrome (HFS) was an independent predictor for better DCR and ORR, and ¹³¹ I-avidity for higher ORR. In univariate analyses, longer PFS and OS were observed in patients with Eastern Cooperative Oncology Group performance status (ECOG PS) ≤2, pathologically well DTC, lung-only metastasis, absence of bone metastasis, biochemically nonineffective response, HFS, or radiological disease control. In multivariate analyses, only well DTC and ECOG PS ≤2 remained as independent prognostic factors for more favorable PFS and OS, respectively, whereas the absence of bone metastasis and biochemically nonineffective response independently predicted superior PFS and OS.

CONCLUSION

This study demonstrated that clinicopathological features might play a vital role in predicting therapeutic outcomes in patients with progressive RR-DTC treated with sorafenib, warranting further optimization of candidates for TKIs.

IMPLICATIONS FOR PRACTICE

This prospective, single-center, real-world study was designed to investigate the significance of clinicopathological features in predicting response, progression-free survival, and overall survival in patients with progressive radioiodine-refractory differentiated thyroid cancer (DTC) treated with sorafenib. Multivariate analyses showed that hand-foot syndrome was an independent predictor for better response. Meanwhile, well DTC, Eastern Cooperative Oncology Group performance status ≤2, biochemically nonineffective response, and the absence of bone metastasis were independent prognostic factors for more favorable survival. This study demonstrated that clinicopathological features might play a vital role in predicting outcomes in sorafenib-treated patients with radioiodine-refractory DTC, warranting optimization of indications.

Lenvatinib and sorafenib for differentiated thyroid cancer after radioactive iodine: a systematic review and economic evaluation

BACKGROUND

Thyroid cancer is a rare cancer, accounting for only 1% of all malignancies in England and Wales. Differentiated thyroid cancer (DTC) accounts for ≈94% of all thyroid cancers. Patients with DTC often require treatment with radioactive iodine. Treatment for DTC that is refractory to radioactive iodine [radioactive iodine-refractory DTC (RR-DTC)] is often limited to best supportive care (BSC).

OBJECTIVES

We aimed to assess the clinical effectiveness and cost-effectiveness of lenvatinib (Lenvima®; Eisai Ltd, Hertfordshire, UK) and sorafenib (Nexar®; Bayer HealthCare, Leverkusen, Germany) for the treatment of patients with RR-DTC.

DATA SOURCES

EMBASE, MEDLINE, PubMed, The Cochrane Library and EconLit were searched (date range 1999 to 10 January 2017; searched on 10 January 2017). The bibliographies of retrieved citations were also examined.

REVIEW METHODS

We searched for randomised controlled trials (RCTs), systematic reviews, prospective observational studies and economic evaluations of lenvatinib or sorafenib. In the absence of relevant economic evaluations, we constructed a de novo economic model to compare the cost-effectiveness of lenvatinib and sorafenib with that of BSC.

RESULTS

Two RCTs were identified: SELECT (Study of [E7080] LEnvatinib in 131I-refractory differentiated Cancer of the Thyroid) and DECISION (StuDy of sorafEnib in loCally advanced or metastatIc patientS with radioactive Iodine-refractory thyrOid caNcer). Lenvatinib and sorafenib were both reported to improve median progression-free survival (PFS) compared with placebo: 18.3 months (lenvatinib) vs. 3.6 months (placebo) and 10.8 months (sorafenib) vs. 5.8 months (placebo). Patient crossover was high (≥ 75%) in both trials, confounding estimates of overall survival (OS). Using OS data adjusted for crossover, trial authors reported a statistically significant improvement in OS for patients treated with lenvatinib compared with those given placebo (SELECT) but not for patients treated with sorafenib compared with those given placebo (DECISION). Both lenvatinib and sorafenib increased the incidence of adverse events (AEs), and dose reductions were required (for > 60% of patients). The results from nine prospective observational studies and 13 systematic reviews of lenvatinib or sorafenib were broadly comparable to those from the RCTs. Health-related quality-of-life (HRQoL) data were collected only in DECISION. We considered the feasibility of comparing lenvatinib with sorafenib via an indirect comparison but concluded that this would not be appropriate because of differences in trial and participant characteristics, risk profiles of the participants in the placebo arms and because the proportional hazard assumption was violated for five of the six survival outcomes available from the trials. In the base-case economic analysis, using list prices only, the cost-effectiveness comparison of lenvatinib versus BSC yields an incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) gained of £65,872, and the comparison of sorafenib versus BSC yields an ICER of £85,644 per QALY gained. The deterministic sensitivity analyses show that none of the variations lowered the base-case ICERs to < £50,000 per QALY gained.

LIMITATIONS

We consider that it is not possible to compare the clinical effectiveness or cost-effectiveness of lenvatinib and sorafenib.

CONCLUSIONS

Compared with placebo/BSC, treatment with lenvatinib or sorafenib results in an improvement in PFS, objective tumour response rate and possibly OS, but dose modifications were required to treat AEs. Both treatments exhibit estimated ICERs of > £50,000 per QALY gained. Further research should include examination of the effects of lenvatinib, sorafenib and BSC (including HRQoL) for both symptomatic and asymptomatic patients, and the positioning of treatments in the treatment pathway.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017055516.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A systematic review of lenvatinib and sorafenib for treating progressive, locally advanced or metastatic, differentiated thyroid cancer after treatment with radioactive iodine

Background

Treatment with radioactive iodine is effective for many patients with progressive, locally advanced or metastatic, differentiated thyroid cancer. However, some patients become refractory to treatment. These types of patients are considered to have radioactive iodine refractory differentiated thyroid cancer (RR-DTC).

Methods

We searched Embase, MEDLINE, PubMed and the Cochrane Library from January 1999 through January 2017. Reference lists of included studies and ongoing trial registries were also searched. Reports of randomized controlled trials (RCTs), prospective observational studies, and systematic reviews/indirect comparisons were eligible for inclusion. In the absence of direct clinical trial evidence comparing lenvatinib versus sorafenib, we assessed the feasibility of conducting an indirect comparison to obtain estimates of the relative efficacy and safety of these two treatments.

Results

Of 2364 citations, in total, 93 papers reporting on 2 RCTs (primary evidence), 9 observational studies and 13 evidence reviews (supporting evidence) were identified. Compared to placebo, RCT evidence demonstrated improvements with lenvatinib or sorafenib in median progression-free survival (PFS) and objective tumour response rate (ORR). Overall survival (OS) was confounded by high treatment crossover (≥75%) in both trials. Adverse events (AEs) were more common with lenvatinib or sorafenib than with placebo but the most common AEs associated with each drug differed. Primarily due to differences in the survival risk profiles of patients in the placebo arms of the RCTs, we considered it inappropriate to indirectly compare the effectiveness of lenvatinib versus sorafenib. ORR and AE findings for lenvatinib and sorafenib from the supporting evidence were broadly in line with RCT evidence. Health-related quality of life (HRQoL) data were limited.

Conclusions

Lenvatinib and sorafenib are more efficacious than placebo (a proxy for best supportive care) for treating RR-DTC. Uncertainty surrounds the extent of the impact on OS and HRQoL. Lenvatinib could not reliably be compared with sorafenib. Choice of treatment is therefore likely to depend on an individual patient’s circumstances.

Prolonged Response to Regorafenib in a Patient with Iodine Refractory Thyroid Cancer

Thyroid cancer is the most common type of endocrine malignancy. Cornerstones of thyroid cancer treatment include surgery, radioactive iodine ablation, and thyroid stimulating hormone suppression. The National Comprehensive Cancer Network guidelines recommend two tyrosine kinase inhibitors for thyroid cancer patients who are non-responsive to iodine: sorafenib and lenvatinib. Another oral kinase inhibitor, regorafenib, is not considered standard of care treatment for differentiated thyroid cancer. The chemical structures of regorafenib and sorafenib differ by a single fluorine atom. Given the significant improvement in progression-free survival (PFS) of sorafenib compared to placebo demonstrated in the phase 3 DECISION trial, we report on a patient with iodine-refractory follicular thyroid cancer treated with regorafenib as part of a phase 1 clinical trial. A 75 year old woman was diagnosed with follicular thyroid carcinoma in 2006 and initiated on treatment with regorafenib in 2011. She has completed 76 cycles with stable disease and pulmonary metastases 34% smaller than baseline.

Tumor doubling time predicts response to sorafenib in radioactive iodine-refractory differentiated thyroid cancer

Sorafenib has emerged as an effective therapeutic option for radioactive iodine (RAI)-refractory, locally advanced or metastatic differentiated thyroid cancer (DTC). We investigated the efficacy and safety of sorafenib treatment in a real-world setting and unveil predictive markers of responsiveness to sorafenib. The treatment response, progression-free survival (PFS), overall survival, and adverse events (AEs) of sorafenib-treated RAI-refractory, locally advanced or metastatic DTC patients at three institutes were retrospectively reviewed, and their tumor doubling time was calculated by three investigators. Total eighty-five patients were treated with sorafenib, and seven patients discontinued sorafenib due to AEs before the first tumor assessment. The median PFS was 14.4 months, and the objective response rate was 10.3% in 78 patients who were able to evaluate the tumor response. Age, sex, histologic type, tumor location, RAI avidity, or the presence of FDG-PET uptake did not affect PFS. However, smaller tumor size (≤1.5 cm) of the target lesions in lung showed better PFS (hazard ratio [HR] 0.39, p = 0.01), and tumors with the shortest doubling time (≤6 months) had worse outcome (HR 2.70, p < 0.01). Because of AEs, dose reductions or drug interruptions were required in 64% of patients, and eventually, 23% of patients discontinued sorafenib permanently. The most common AE was hand-foot skin reaction (HFSR). Patients with severe HFSR showed better PFS, but there were no statistical significance (HR 0.65, p = 0.05). In conclusion, small tumor size and long doubling time of each target lesion can be a prognostic marker to predict the responsiveness to sorafenib in RAI-refractory DTC patients.

Efficacy and toxicity of sorafenib in the treatment of advanced medullary thyroid carcinoma: A systematic review and meta-analysis

INTRODUCTION

The aim of this study is to investigate and summarize the treatment efficacy and adverse effects (AEs) of sorafenib in the treatment of metastatic medullary thyroid carcinomas (MTCs).

METHODS

We included studies reporting the treatment efficacy or drug toxicity of sorafenib as a single therapeutic agent in MTCs. Pooled incidence and its 95% confidence interval (CI) for complete response, partial response (PR), stable disease (SD), and sorafenib-related AEs were calculated using random-effect model.

RESULTS

Eight trials with 101 metastatic MTCs were included for meta-analyses. The overall PR and SD were 21% (95% CI = 9-33) and 58% (95% CI = 41-75), respectively. Hand-foot syndrome, diarrhea, alopecia, mucositis, skin rash, fatigue, and hypertension were the most commonly observed AEs.

CONCLUSION

Our results show that sorafenib treatment has a modest effect and might be a candidate treatment in patients with metastatic MTCs who have failed other therapeutic regimens.

Targeted next-generation sequencing in papillary thyroid carcinoma patients looking for germline variants predisposing to the disease

PURPOSESS

The purpose of this study was using next-generation sequencing technique to explore the potential association between germline variants of 14 targeted genes and papillary thyroid carcinoma (PTC) predisposition as well as disease progression.

METHODS

In all, 516 subjects were enrolled in this study including 416 PTC patients and 100 healthy controls. PTC patients were divided into distant metastasis group and non-distant metastasis group. Patients in distant metastasis group were further divided into radioiodine-refractory PTC (RR-PTC) and non-RR-PTC depending on their response to radioiodine therapy. Genomic DNA was extracted from peripheral blood sample and MiSeq Benchtop Sequencer was used for sequencing.

RESULTS

We found rs11246050 in NLRP6 (dominant model, OR/95% CI: 2.028/1.091-3.769, p = 0.025), rs2286742 and rs3740530 in HABP2 (recessive model, OR/95% CI: 9.644/1.307-71.16, p = 0.026 and 3.989/1.413-11.26, p = 0.009), rs2736098 in TERT (recessive model, OR/95% CI: 2.322/1.028-5.242. p = 0.042) and rs62054619 in GAS8-AS1 (recessive model, OR/95% CI: 2.219/1.067-4.617, p = 0.033) were associated with the risk of PTC. rs1137282 in KRAS (dominant model, OR/95% CI: 0.5430/0.3192-0.9236, p = 0.024), rs1347591 and rs4461062 in NUP93 (dominant model, OR/95% CI: 0.6121/0.4128-0.9076, p = 0.015 and 0.6156/0.4157-0.9117, p = 0.015) were associated with low risk of distant metastatic disease in PTC patients. rs33954691 in TERT was associated with the risk of RR-PTC under dominant model (OR/95% CI: 3.161/1.596-6.262).

CONCLUSIONS

Germline variants of related genes could be associated with the susceptibility of PTC as well as disease progression (distant metastasis and radioiodine-refractory status). However, these results must be further verified and the potential biological functions of these germline variants in the pathogenesis of PTC remain to be determined in future studies.

A Phase II study of the safety and efficacy of lenvatinib in patients with advanced thyroid cancer

Aim: To investigate the safety and efficacy of lenvatinib in advanced thyroid cancer. Patients/methods: In this Phase II study, 51 Japanese patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC), medullary thyroid cancer (MTC) or anaplastic thyroid cancer (ATC) received once-daily lenvatinib 24 mg. The primary end point was safety. Results: All patients experienced ≥1 adverse event (AE); only one patient experienced an AE leading to discontinuation. The most common any-grade AEs were hypertension, decreased appetite, palmar-plantar erythrodysesthesia, fatigue and proteinuria. Response rates for RR-DTC: 68%; MTC: 22%; ATC: 24%. Median progression-free survival for RR-DTC: 25.8 months; MTC: 9.2 months; ATC: 7.4 months. Conclusion: Lenvatinib demonstrated a manageable safety profile, proven antitumor activity in RR-DTC and promising efficacy in MTC and ATC.

Clinical trial registration: clinicaltrials.gov NCT01728623

Sequence‑dependent effect of sorafenib in combination with natural phenolic compounds on hepatic cancer cells and the possible mechanism of action

Sorafenib (Nexavar, BAY43-9006 or Sora) is the first molecular targeted agent that has exhibited significant therapeutic benefits in advanced hepatocellular carcinoma (HCC). However, not all HCC patients respond well to Sora and novel therapeutic strategies to optimize the efficacy of Sora are urgently required. Plant-based drugs have received increasing attention owing to their excellent chemotherapeutic and chemopreventive activities; they are also well tolerated, non-toxic, easily available and inexpensive. It is well known that certain biologically active natural products act synergistically with synthetic drugs used in clinical applications. The present study aimed to investigate whether a combination therapy with natural phenolic compounds (NPCs), including curcumin (Cur), quercetin (Que), kaempherol (Kmf) and resveratrol (Rsv), would allow a dose reduction of Sora without concomitant loss of its effectiveness. Furthermore, the possible molecular mechanisms of this synergy were assessed. The hepatic cancer cell lines Hep3b and HepG2 were treated with Sora alone or in combination with NPCs in concomitant, sequential, and inverted sequential regimens. Cell proliferation, cell cycle, apoptosis and expression of proteins associated with the cell cycle and apoptosis were investigated. NPCs markedly potentiated the therapeutic efficacy of Sora in a sequence-, type-, NPC dose- and cell line-dependent manner. Concomitant treatment with Sora and Cur [sensitization ratio (SR)=28], Kmf (SR=18) or Que (SR=8) was associated with the highest SRs in Hep3b cells. Rsv markedly potentiated the effect of Sora (SR=17) on Hep3b cells when administered in a reverse sequential manner. By contrast, Rsv and Que did not improve the efficacy of Sora against HepG2 cells, while concomitant treatment with Cur (SR=10) or Kmf (SR=4.01) potentiated the cytotoxicity of Sora. Concomitant treatment with Sora and Cur or Kmf caused S-phase and G2/M phase arrest of liver cancer cells and markedly induced apoptosis compared with mono-treatment with Sora, Cur or Kmf. Concomitant treatment with Sora and Cur reduced the protein levels of cyclins A, B2 and D1, phosphorylated retinoblastoma and B-cell lymphoma (Bcl) extra-large protein. By contrast, Sora and Cur co-treatment increased the protein levels of Bcl-2-associated X protein, cleaved caspase-3 and cleaved caspase-9 in a dose-dependent manner. In conclusion, concomitant treatment with Sora and Cur or Kmf appears to be a potent and promising therapeutic approach that may control hepatic cancer by triggering cell cycle arrest and apoptosis. Additional studies are required to examine the potential of combined treatment with Sora and NPCs in human hepatic cancer and other solid tumor types in vivo.

Postsurgical Management of Differentiated Thyroid Cancer in China

Postsurgical management of differentiated thyroid cancer in China has gained a great success in the last twenty years, but there are still gaps to be filled. Here, we briefly review the current status and also extend an outlook for future development.

Thyroid autoimmune antibodies in patients with papillary thyroid carcinoma: a double-edged sword?

PURPOSE

The relationship between thyroid autoimmunity and thyroid cancer remains controversial. The objective of this study is to comprehensively analyze the association between thyroid autoimmune antibodies and disease statuses of papillary thyroid carcinoma (PTC).

METHODS

Patients were divided into different groups according to their final diagnoses after radioiodine therapy as well as their serum anti-thyroglobulin antibody (TgAb) and anti-thyroidperoxidase antibody (TPOAb) titers. Clinicopathologic characteristics were then compared between groups.

RESULTS

In all, 1126 PTC patients met the inclusion criteria. When compared with thyroid autoimmune antibody negative group, patients in positive group were young female predominant. After age and gender adjusted, patients in thyroid autoimmune antibody positive group had much more cervical metastatic node count and this effect was limited to the central compartment but not to the lateral compartment. Antibody positivity rate was much lower in patients with distant metastasis and multivariable logistic regression analysis showed positive status of antibody was a protective factor of distant metastasis of PTC with an OR value of 0.403 (95% CI 0.216-0.622, p < 0.001). Additionally, subgroup analysis demonstrated single TgAb positivity and combined positivity of TgAb and TPOAb were shown to be related to less distant metastatic disease.

CONCLUSIONS

Positive thyroid auto-antibody status could be a risk factor of more metastatic cervical lymph nodes while a protective factor of distant metastatic disease in PTC patients. The association between thyroid autoimmunity and thyroid cancer can be patient and antibody specific. A systemic immunosupression status may exist in PTC patients with distant metastasis.

Advances in small molecule therapy for treating metastatic thyroid cancer

INTRODUCTION

Multi kinase inhibitors (MKIs) are new drugs, which show activity against receptors of different growth factors leading to the inhibition of tumor cells growth and proliferation. This review summarizes a 10-year experience with the use of MKIs in thyroid cancer (TC). It focuses not only on sorafenib, lenvatinib, vandetanib and cabozantinib, already approved in TC, but also presents an overview of the results of different trials with distinct MKIs so far carried out in TC. Areas covered: Published results of phase I, II and III studies and other reports evaluated the efficacy of different targeted drugs in TC. Expert opinion: Despite numerous clinical trials with distinct MKIs, only four of them unequivocally demonstrated a beneficial effect on progression free survival in radioiodine refractory differentiated or medullary TC. In contrast to other solid tumors, we are still lacking in convincing evidences of their impact on overall survival. We still do not have any strong proof fulfilling evidence-based medicine criteria, when to start MKIs and which drug to use. The questions whether we really have to wait for disease progression in patients with a large tumor burden and/or aggressive types TC or when to stop MKIs treatment remain open.

Targeted therapies in thyroid cancer: an extensive review of the literature

INTRODUCTION

Patients with progressive, metastatic, RAI-refractory differentiated thyroid cancer (DTC), as well as patients with advanced medullary (MTC) and anaplastic thyroid cancer represent a cohort for which therapeutic options are limited. The recent discoveries in the molecular mechanisms implicated in TC have provided insight of the pathogenesis and progression of disease. In that respect, targeted therapies have emerged as a promising alternative for the treatment of those patients. Areas covered: Tyrosine Kinase Inhibitors (TKIs) have been studied extensively in TC: sorafenib and lenvatinib have been approved by the FDA for the treatment of metastatic, RAI-refractory DTC, while vandetanib and cabozantinib are FDA approved for use in advanced MTC. Moreover, several additional TKIs, multi-targeted or specific, are currently under investigation in TC. The current manuscript provides an extensive review of the literature regarding targeted therapies in TC including the rationale behind their use, the clinical trials and an expert opinion on their use. Literature in English appearing at PubMed was thoroughly reviewed, especially manuscripts of the last 5 years. Expert commentary: Patients with advanced, progressive, metastatic TC should be evaluated for enrollment in a clinical trial or should be placed on treatment with one of the FDA- and EMA- approved agents.

Selective use of sorafenib in the treatment of thyroid cancer

Sorafenib is a multiple kinase inhibitor (MKI) approved for the treatment of primary advanced renal cell carcinoma and advanced primary liver cancer. It was recently approved by several health agencies around the world as the first available MKI treatment for radioactive iodine-refractory advanced and progressive differentiated thyroid cancer. Sorafenib targets C-RAF, B-RAF, VEGF receptor-1, -2, -3, PDGF receptor-β, RET, c-kit, and Flt-3. As a multifunctional inhibitor, sorafenib has the potential of inhibiting tumor growth, progression, metastasis, and angiogenesis and downregulating mechanisms that protect tumors from apoptosis and has shown to increase the progression-free survival in several Phase II trials. This led to the Phase III trial (DECISION) which showed that there was an improvement in progression-free survival of 5 months for patients on sorafenib when compared to those on placebo. Adverse events with this drug are common but usually manageable. The development of resistance after 1 or 2 years is almost a rule in most patients who showed partial response or stabilization of the disease while on sorafenib, which makes it necessary to think of a plan for subsequent therapies. These may include the use of another MKI, such as lenvatinib, the second approved MKI for advanced differentiated thyroid cancer, or include patients in clinical trials or the off-label use of other MKIs. Given sorafenib's earlier approval, most centers now have access to its prescription. The goal of this review was to improve the care of these patients by describing key aspects that all prescribers will need to master in order to optimize outcomes.

Subgroup analysis of Japanese patients in a phase 3 study of lenvatinib in radioiodine-refractory differentiated thyroid cancer

Lenvatinib significantly prolonged progression-free survival (PFS) versus placebo in patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC) in the phase 3 Study of (E7080) Lenvatinib in Differentiated Cancer of the Thyroid (SELECT) trial. This subanalysis evaluated the efficacy and safety of lenvatinib in Japanese patients who participated in SELECT. Outcomes for Japanese patients (lenvatinib, n = 30; placebo, n = 10) were assessed in relationship to the SELECT population (lenvatinib, n = 261; placebo, n = 131). The primary endpoint was PFS; secondary endpoints included overall survival, overall response rate, and safety. Lenvatinib PFS benefit was shown in Japanese patients (median PFS: lenvatinib, 16.5 months; placebo, 3.7 months), although significance was not reached, presumably due to sample size (hazard ratio, 0.39; 95% confidence interval, 0.10-1.57; P = 0.067). Overall response rates were 63.3% and 0% for lenvatinib and placebo, respectively. No significant difference was found in overall survival. The lenvatinib safety profile was similar between the Japanese and overall SELECT population, except for higher incidences of hypertension (any grade: Japanese, 87%; overall, 68%; grade ≥3: Japanese, 80%; overall, 42%), palmar-plantar erythrodysesthesia syndrome (any grade: Japanese, 70%; overall, 32%; grade ≥3: Japanese, 3%; overall, 3%), and proteinuria (any grade: Japanese, 63%; overall, 31%; grade ≥3: Japanese, 20%; overall, 10%). Japanese patients had more dose reductions (Japanese, 90%; overall, 67.8%), but fewer discontinuations due to adverse events (Japanese, 3.3%; overall, 14.2%). There was no difference in lenvatinib exposure between the Japanese and overall SELECT populations after adjusting for body weight. In Japanese patients with radioiodine-refractory differentiated thyroid cancer, lenvatinib showed similar clinical outcomes to the overall SELECT population. Some differences in adverse event frequencies and dose modifications were observed. Clinical trial registration no.: NCT01321554.

Sorafenib treatment of radioiodine-refractory advanced thyroid cancer in daily clinical practice: a cohort study from a single center

Treatment options for recurrent or metastatic differentiated thyroid cancer (DTC) refractory to radioactive iodine (RAI) are inadequate. Multitargeted kinase inhibitors have recently shown promising results in phase 2-3 studies. This retrospective study aimed to document our clinical experience on the effects of sorafenib in the setting of daily clinical practice. Retrospective study evaluating the efficacy and safety of sorafenib in a cohort of patients consecutively treated with sorafenib at a single center. Twenty patients with advanced RAI-refractory thyroid carcinoma were enrolled (March 2011-March 2014). Patients generally started with 400 mg of sorafenib twice daily, tapering the dose in case of side effects. Radiological response and toxicity were measured during follow-up, together with safety parameters. CT scans were performed by a single experienced radiologist every 3-4 months. Five patients stopped sorafenib within 90 days due to severe toxicities. Median progression-free survival was 248 days. Five patients had a partial response (PR), achieved in all cases within 3 months, whereas 5 had stable disease (SD) at 12 months. Durable response rate (PR plus SD) for at least 6 months was 50 %, among those who received sorafenib for at least 3 months. Commonest adverse events included skin toxicity, gastrointestinal and constitutional symptoms. In our cohort of patients with advanced RAI-refractory thyroid carcinoma, sorafenib confirmed antitumor activity leading to SD or PR in the majority of cases, at the expense of clinically relevant side effects. More effective and tolerable agents are still needed in the treatment of RAI-refractory DTC.

Simultaneous suppression of the MAP kinase and NF-κB pathways provides a robust therapeutic potential for thyroid cancer

The MAP kinase and NF-κB signaling pathways play an important role in thyroid cancer tumorigenesis. We aimed to examine the therapeutic potential of dually targeting the two pathways using AZD6244 and Bortezomib in combination. We evaluated their effects on cell proliferation, cell-cycle progression, apoptosis, cell migration assay, and the activation of the MAPK pathway in vitro and the in vivo using tumor size and immunohistochemical changes of Ki67 and ppRB. We found inhibition of cell growth rate by 10%, 20%, and 56% (p <0.05), migration to 55%, 61%, and 29% (p <0.05), and induction of apoptosis to 10%, 15%, and 38% (p <0.05) with AZD6244, Bortezomib, or combination, respectively. Induction of cell cycle arrest occurred only with drug combination. Dual drug treatment in the xenograft model caused a 94% reduction in tumor size (p <0.05) versus 15% with AZD6244 and 34% with Bortezomib (p < 0.05) and also reduced proliferative marker Ki67, and increased pRb dephosphorylation. Our results demonstrate a robust therapeutic potential of combining AZD6244 and Bortezomib as an effective strategy to overcome drug resistance encountered in monotherapy in the treatment of thyroid cancer, strongly supporting clinical trials to further test this strategy.

Therapy of endocrine disease: response and toxicity of small-molecule tyrosine kinase inhibitors in patients with thyroid carcinoma: a systematic review and meta-analysis

CONTEXT

Many tyrosine kinase inhibitors (TKIs) have been studied in patients with thyroid carcinoma (TC). However, the effect and toxicity of various TKIs in differentiated TC (DTC) and medullary TC (MTC) patients have not been directly compared. The aim of the present systematic review and meta-analysis was to systematically summarize response and toxicity of TKIs in TC patients.

METHODS

All major databases were systematically searched for publications on TKIs in TC. Primary endpoint was objective response; secondary endpoints were clinical benefit, percentage TKI dose reduction/discontinuation, hand-foot syndrome, diarrhea, and nausea/vomiting. Meta-analysis was performed using an exact likelihood approach and a logistic regression. Pooled percentages and 95% CIs were reported.

RESULTS

In total, 22 publications were included. For DTC patients, gefitinib induced no objective responses. Pooled percentage was highest for pazopanib, 49 (95% CI 33-64)%, and was 17 (95% CI 12-24)% for sorafenib. For MTC, gefitinib and imatinib induced no objective responses, whereas sunitinib induced objective response in 43 (95% CI 14-77)%. For vandetanib and cabozantinib, these numbers were 40 (95% CI 34-46)% and 27 (95% CI 22-32)% respectively. Clinical benefit was found in 53 (95% CI 48-59)% of DTC patients on sorafenib, and in 84 (95% CI 79-88)% and 55 (95% CI 49-61)% of MTC patients on vandetanib and cabozantinib respectively. All TKIs were associated with considerable toxicity.

CONCLUSION

The currently studied TKIs show a modest response, while side effects are not negligible. Therefore, we suggest to solely consider TKIs in TC patients with rapid progressive disease, for whom the benefits of treatment outweigh toxicity.

Sorafenib: a review of its use in patients with radioactive iodine-refractory, metastatic differentiated thyroid carcinoma

Sorafenib (Nexavar®) is the first tyrosine kinase inhibitor to be approved for the treatment of radioactive iodine (RAI)-refractory differentiated thyroid carcinoma (DTC). In the pivotal phase III DECISION trial in patients with RAI-refractory, locally advanced or metastatic DTC, oral sorafenib 400 mg twice daily significantly prolonged median progression-free survival (PFS) relative to placebo. The PFS benefit of sorafenib over placebo was evident in all pre-specified clinical and genetic biomarker subgroups, and neither BRAF nor RAS mutation status was predictive of sorafenib benefit for PFS. The objective response rate was significantly higher in patients receiving sorafenib than in those receiving placebo; all objective responses were partial responses. The overall survival benefit of sorafenib is as yet unclear, with no significant benefit observed at the time of primary analysis or at 9 months following the primary analysis. Overall survival was possibly confounded by the crossover of patients in the placebo group to sorafenib upon disease progression. The adverse events associated with sorafenib in the DECISION trial were consistent with the known tolerability profile of the drug, with hand-foot skin reaction, diarrhea, and alopecia reported most commonly. Most treatment-emergent adverse events were grade 1 or 2 in severity and occurred early in treatment. However, a high proportion of patients discontinued sorafenib therapy or required dose reductions or interruptions because of toxicity. Although final overall survival data are awaited, current evidence suggests that sorafenib is a promising new treatment option for patients with RAI-refractory, metastatic DTC.

Synergistic anti-proliferative effect of metformin and sorafenib on growth of anaplastic thyroid cancer cells and their stem cells

Sorafenib, a multikinase inhibitor has recently been approved for the treatment of radio-iodine refractory thyroid carcinoma. However, toxic side effects may lead to dose reduction. In the present study, we analyzed whether a combined therapy with metformin may allow a dose reduction of sorafenib without loss of effectiveness at the same time. In HTh74 anaplastic thyroid carcinoma (ATC) cells and its derived doxorubicin-resistant HTh74Rdox cell line, the growth inhibitory effect of sorafenib with or without metformin was investigated. Furthermore, an analysis of cell cycle arrest in response to sorafenib was performed and the ability of a combined treatment to induce apoptosis was analyzed. In addition, the effects on clonal growth and formation of stem cell-derived spheres were assayed. The influence of sorafenib and metformin on MAP kinase pathway was investigated by analysis of ERK phosphorylation. Sorafenib and metformin synergistically inhibited growth of the two thyroid cancer cell lines, with a more pronounced effect on the doxorubicin-resistant HTh74Rdox cell line. The two drugs also synergistically decreased sphere formation, which suggested a specific effect on thyroid cancer stem cells. The addition of metformin enabled a 25% dose reduction of sorafenib without loss of its growth inhibitory efficacy. Sorafenib and metformin synergistically decreased the proliferation of ATC cell lines and the outgrowth of their derived cancer stem cells. A combined treatment enabled a significant dose reduction of sorafenib. In respect to frequent toxic side effects, clinical studies in future should demonstrate whether the addition of metformin may be an advantage in the chemotherapy of patients with radio-iodine‑resistant thyroid cancer.

Aberrant expression of COT is related to recurrence of papillary thyroid cancer

Aberrant expression of Cancer Osaka Thyroid Oncogene mitogen-activated protein kinase kinase kinase 8 (COT) (MAP3K8) is a driver of resistance to B-RAF inhibition. However, the de novo expression and clinical implications of COT in papillary thyroid cancer (PTC) have not been investigated.The aim of this study is to investigate the expression of A-, B-, C-RAF, and COT in PTC (n = 167) and analyze the clinical implications of aberrant expression of these genes.Quantitative polymerase chain reaction (qPCR) and immunohistochemical staining (IHC) were performed on primary thyroid cancers. Expression of COT was compared with clinicopathological characteristics including recurrence-free survival. Datasets from public repository (NCBI) were subjected to Gene Set Enrichment Analysis (GSEA).qPCR data showed that the relative mRNA expression of A-, B-, C-RAF and COT of PTC were higher than normal tissues (all P < 0.01). In addition, the expression of COT mRNA in PTC showed positive correlation with A- (r = 0.4083, P < 0.001), B- (r = 0.2773, P = 0.0003), and C-RAF (r = 0.5954, P < 0.001). The mRNA expressions of A-, B,- and C-RAF were also correlated with each other (all P < 0.001). In IHC, the staining intensities of B-RAF and COT were higher in PTC than in normal tissue (P < 0.001). Interestingly, moderate-to-strong staining intensities of B-RAF and COT were more frequent in B-RAF-positive PTC (P < 0.001, P = 0.013, respectively). In addition, aberrant expression of COT was related to old age at initial diagnosis (P = 0.045) and higher recurrence rate (P = 0.025). In multivariate analysis, tumor recurrence was persistently associated with moderate-to-strong staining of COT after adjusting for age, sex, extrathyroidal extension, multifocality, T-stage, N-stage, TNM stage, and B-RAF mutation (odds ratio, 4.662; 95% confidence interval 1.066 - 21.609; P = 0.045). Moreover, moderate-to-strong COT expression in PTC was associated with shorter recurrence-free survival (mean follow-up duration, 14.2 ± 4.1 years; P = 0.0403). GSEA indicated that gene sets related to B-RAF-RAS (P < 0.0001, false discovery rate [FDR] q-value = 0.000) and thyroid differentiation (P = 0.048, FDR q-value = 0.05) scores were enriched in lower COT expression group and gene sets such as T-cell receptor signaling pathway and Toll-like receptor signaling pathway are coordinately upregulated in higher COT expression group (both, P < 0.0001, FDR q-value = 0.000).Aberrant expression of A-, B-, and C-RAF, and COT is frequent in PTC; increased expression of COT is correlated with recurrence of PTC.

Sorafenib for the treatment of thyroid cancer: an updated review

INTRODUCTION

Sorafenib (Nexavar) is an oral multi-kinase inhibitor targeting B-type Raf kinase (BRAF) (both wild type and BRAF(V600E)), VEGFR1, VEGFR2, VEGFR3, PDGFRβ and RET (also RET/PTC) influencing both differentiated thyroid cancer (DTC) cell proliferation and angiogenesis.

AREAS COVERED

Encouraging results achieved in numerous Phase II trials were confirmed in a Phase III study conducted in radioiodine-refractory DTC. Sorafenib compared to placebo significantly prolongs progression-free survival, 10.8 versus 5.8 months, respectively. However, its administration resulted mainly in disease stabilization. No complete remission was obtained in any study. Beneficial effects were also demonstrated for medullary and anaplastic thyroid cancer; however further studies fulfilling evidence based medicine criteria are necessary. Its toxicity profile is convergent with other VEGFR inhibitors. The most common treatment-related side-effects involve skin toxicity (predominantly hand-foot skin reaction, different rashes and alopecia), gastrointestinal disturbances (diarrhea, abdominal pain), constitutional adverse reactions (anorexia, weight loss, fatigue) and hypertension. Although most adverse reactions are manageable, > 50% of patients required dose reduction.

EXPERT OPINION

Sorafenib constitutes the first line treatment option in advanced, radioiodine-refractory DTC. However, there are still no data on its efficacy in patients progressed after another tyrosine kinase inhibitor. Other applications of the drug, such as use as adjuvant therapy to 131-I treatment, requires further studies.

Advances in thyroid cancer treatment: latest evidence and clinical potential

Advanced thyroid carcinoma is an infrequent tumor entity with limited treatment possibilities until recently. The extraordinary improvement in the comprehension of genetic and molecular alterations involving the RAS/RAF/mitogen-activated protein kinase and phosphatidylinositide 3-kinase/Akt/mammalian target of rapamycin signaling and interacting pathways that are involved in tumor survival, proliferation, differentiation, motility and angiogenesis have been the rationale for the development of new effective targeted therapies. Data coming from phase II clinical trials have confirmed the efficacy of those targeted agents against receptors in cell membrane and cytoplasmic molecules. Moreover, four of those investigational drugs, vandetanib, cabozantinib, sorafenib and lenvatinib, have reached a phase III clinical trial with favorable results in progression-free survival and overall survival in medullary thyroid carcinoma and differentiated thyroid carcinoma. Further analysis for an optimal approach has been conducted according to mutational profile and tumor subtypes. However, consistent results are still awaited and the research for adequate prognostic and predictive biomarkers is ongoing. The following report offers a comprehensive review from the rationale to the basis of targeted agents in the treatment of thyroid carcinoma. In addition, current and future therapeutic developments by the inhibition of further molecular targets are discussed in this setting.

Targeting vascular endothelial growth factor (VEGF) pathway in iodine-refractory differentiated thyroid carcinoma (DTC): from bench to bedside

Thyroid cancer is the most common endocrine malignancy, representing 1% of all human malignancies; its incidence has been escalating worldwide during the last decades. In recent years important molecular pathways contributing to tumor progression and worse survival rates have been identified in iodine-refractory differentiated thyroid carcinoma (DTC) with the consequent development of molecular therapeutics to target these specific oncogenic pathways. For example, a positive correlation has been found between expression of vascular endothelial growth factor (VEGF) and a more aggressive phenotype of DTC. This has led to the widespread adoption of VEGF-targeted therapeutics in the preclinical and clinical settings. In this review we will provide an overview of the different aspects of the use of VEGF-pathway-oriented treatments in iodine-refractory DTC with particular focus on future prospects.

Sorafenib in radioactive iodine-refractory well-differentiated metastatic thyroid cancer

Recent Phase III data presented at the American Society of Clinical Oncology (ASCO) 2013 annual conference by Brose et al led to the US Food and Drug Administration (FDA) approval of sorafenib for the treatment of well-differentiated radioactive iodine-resistant metastatic thyroid cancer. This is the second drug in 40 years to be FDA approved for this indication. Recent reviews and a meta-analysis reveal a modest ability to induce a partial remission but substantial ability to halt disease progression. Given the significant activating mutations present in thyroid cancer, many of which are inhibited by sorafenib, the next logical approach may be to combine targeted rational therapies if permitted by collective toxicity profiles. This systematic review aims to summarize the recent Phase II/III data leading to the FDA approval of sorafenib for radioactive iodine therapy differentiated thyroid cancer and highlights recent novel combination therapy trials.

Molecular pathways associated with aggressiveness of papillary thyroid cancer

The most common thyroid malignancy is papillary thyroid cancer (PTC). Mortality rates from PTC mainly depend on its aggressiveness. Geno- and phenotyping of aggressive PTC has advanced our understanding of treatment failures and of potential future therapies. Unraveling molecular signaling pathways of PTC including its aggressive forms will hopefully pave the road to reduce mortality but also morbidity from this cancer. The mitogen-activated protein kinase and the phosphatidylinositol 3-kinase signaling pathway as well as the family of RAS oncogenes and BRAF as a member of the RAF protein family and the aberrant expression of microRNAs miR-221, miR-222, and miR-146b all play major roles in tumor initiation and progression of aggressive PTC. Small molecule tyrosine kinase inhibitors targeting BRAF-mediated events, vascular endothelial growth factor receptors, RET/PTC rearrangements, and other molecular targets, show promising results to improve treatment of radioiodine resistant, recurrent, and aggressive PTC.

Drug safety evaluation of sorafenib for treatment of solid tumors: consequences for the risk assessment and management of cancer patients

INTRODUCTION

Sorafenib is a multi-tyrosine kinase inhibitor (TKI). Considerable clinical experience has been accumulated since its first Phase III clinical trial in metastatic renal cancer patients in 2007. The management of its early acute toxicity in fit patients is well known. The management of prolonged treatment becomes the new challenge.

AREAS COVERED

Using sorafenib as a key word for PubMed search, we review preclinical and clinical data and discuss the pharmacokinetics and pharmacodynamics of sorafenib, its acute and cumulative toxicities and their consequences for patient management.

EXPERT OPINION

The systematic multi-disciplinary risk assessment of cancer patients prior to TKI initiation reduces the risks of acute and late toxicity, especially drug-drug interactions and arterial risks. Sarcopenia is now identified as a major risk of severe toxicity. The very diverse clinical pictures of cumulative toxicity must be known. The monitoring of sorafenib systemic exposure is helpful especially in elderly patients. Moreover, at disease progression, it allows distinguishing between underexposure to sorafenib and truly acquired resistance to the drug. The optimal use of sorafenib should allow improving the reported results of flat-dose. Finally, most of this knowledge could be used for the development and optimal use of the other TKIs.

Sorafenib: is a partial response and stabilization of disease greater than 70% a modest response?

Extract: Dear Editors, I read with great interest the recently published meta-analysis on sorafenib use in patients with radioiodine refractory thyroid cancer (Shen et al. 2013). In this study, 7 investigations were analyzed and pooled results showed than more than 70% of patients achieved a partial response (PR) or stabilization of disease (SD) with a median progression free survival of one year. Also, the authors showed than around 80% of patients presented side effects when all grades adverse events (AE) were considered. The authors concluded that sorafenib showed only a modest effect in patients with advanced thyroid cancer. I wonder if 70% of PR plus SD would be considered as a modest response to treatment in patients with advanced progressive disease with few other therapeutic options available at this moment.