Management of undifferentiated thyroid cancer

Remarkable 99mTc-FAPI-46 Uptake in a Patient With Anaplastic Thyroid Carcinoma: A Promising Step in Theranostic Field

Fibroblast activation protein (FAP)-targeted radionuclides are known as a promising step in cancer diagnosis and treatment (theranostic), although it is still a subject under investigation. We present a patient with anaplastic thyroid carcinoma who underwent 99mTc-FAPI-46 SPECT/CT for the evaluation of metastatic disease. Several metastatic sites were found with considerable 99mTc-FAPI-46 uptake. Malignant FAPI uptake was observed in the large calcified thyroid mass, mediastinal lymph node, both lungs, liver, few skeletal sites, and around knees prostheses. Given the notable uptake of lesions, the patient was considered as a candidate for FAP-targeted radionuclide therapy.

Imaging and dosimetry for alpha-particle emitter radiopharmaceutical therapy: improving radiopharmaceutical therapy by looking into the black box

Radiopharmaceutical therapy using α-particle emitting radionuclides (αRPT) is a novel treatment modality that delivers highly potent alpha-particles to cancer cells or their environment. We review the advantages and challenges of imaging and dosimetry in implementing αRPT for cancer patients.

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

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

Combined Effects of Baicalein and Docetaxel on Apoptosis in 8505c Anaplastic Thyroid Cancer Cells via Downregulation of the ERK and Akt/mTOR Pathways

BACKGROUND

Anaplastic thyroid cancer (ATC) is one of the most lethal human malignancies. Docetaxel, a microtubule stabilizer, is a common chemotherapeutic agent used to treat various metastatic cancers. However, prolonged use results in various side effects and drug resistance. Flavonoids, such as baicalein, are accepted chemotherapeutic and dietary chemopreventive agents with many advantages, such as greater accessibility, affordability, and lower toxicity, compared with traditional chemotherapy agents. In this study, we evaluated whether baicalein enhances the effects of docetaxel on apoptosis and metastasis in 8505c ATC cells.

METHODS

The 8505c cells were treated with baicalein or docetaxel individually and in combination. Cell viability was measured by MTT (thiazolyl blue tetrazolium bromide) assay, and apoptosis was detected by fluorescence microscopy of Hoechst-stained cells. The expression of apoptotic (Bax and caspase-3), anti-apoptotic (Bcl-2), angiogenic (vascular endothelial growth factor [VEGF], transforming growth factor β [TGF-β], E-cadherin, and N-cadherin), and signaling (extracellular signal-regulated kinase [ERK] mitogen activated protein kinase [MAPK], Akt, and mammalian target of rapamycin [mTOR]) proteins was determined by Western blot analysis.

RESULTS

The combination of baicalein (50 or 100 μM) and docetaxel (10 nM) significantly inhibited proliferation and induced apoptosis compared with monotherapies. The combination treatment significantly inhibited the expression of Bax, caspase-3, VEGF, TGF-β1, E-cadherin, N-cadherin, and mTOR, but decreased the expression of Bcl-2 and significantly decreased the phosphorylation of ERK and Akt.

CONCLUSION

The combination of baicalein and docetaxel effectively induced apoptosis and inhibited metastasis in 8505c cells through downregulation of apoptotic and angiogenic protein expression and blocking of the ERK and Akt/mTOR pathways in 8505c cells. These results suggest that baicalein enhances the anticancer effects of docetaxel in ATC.

Problematic clinical trials in thyroid cancer: the issue of papillary carcinoma and observational approaches

We describe the clinical ethics problem of American thyroid cancer patients being offered ‘observation’ instead of the USA standard of care with questionable informed consent. This problem arose because some American practitioners misinterpreted 1990s Japanese studies. American proponents of these studies failed to recognize major differences in ethical oversight between Japanese and US clinical research, misrepresenting these studies as justifying clinical practices for higher risk patients that were not supported by data. The current professional environment in American thyroid cancer management is sufficiently problematic that consideration should be made, for patients who have inadvertently consented to nonevidence-based treatments, to be recontacted and provided an opportunity to revisit their care plans or seek second opinions regarding an observational approach.

Informed consent for low-risk thyroid cancer

Significant barriers to informed consent surround the clinical management of adult patients with well-differentiated thyroid cancer. The literature reveals lack of disclosure surrounding clinical equipoise; confusing and conflicting terminology; and an insufficient number of prospective trials with proper ethical oversight. We provide guidance for valid consent to treatment in this population, and propose stipulative definitions for a variety of terms used in this context. Three critical areas are addressed: surgical management, radioactive iodine management and nonvalidated practice. Sound ethical frameworks for valid consent in patients with low-risk thyroid cancer include consent to observational (or ‘active surveillance’) research protocols, consent to nonvalidated practice and consent when there are opposing standards of care due to insufficient data and disagreement among the community of experts.

The role of surgery in the treatment of thyroid anaplastic carcinoma in the elderly

INTRODUCTION

Anaplastic thyroid carcinoma (ATC) is characterized by local invasiveness, risk of recurrence and very poor prognosis.

METHODS

We retrospectively analysed the multimodality treatment of ATC in 79 patients considering the impact of surgery on survival.

RESULTS

Patients were divided in two age groups A and B (cut-off 75 years) and in two size subgroups (cut-off 5 cm). Surgery was performed in 78.5% patients of group A and 32.4% of B (p < 0.05). Radiation respectively in 73.8% and 43.2% (p < 0.05). Tracheostomy and endoprosthesis were used in 45.2% and 16.6% in group A and in 43.2% and 35.1% in group B. The use of tracheostomy was significantly higher (p < 0.05) in larger tumours. In group B comparing operated and not operated patients significant difference in survival was observed for larger tumours (p = 0.043). In Kaplan Meir analysis significant difference in survival was observed comparing surgical and no surgical patients of all four subgroups. Surgery plus radiotherapy offered a significant better outcome in smaller tumours (p = 0.017). Considering the effect of the single treatment, compared to no treatment at all, survival is significantly improved by surgery for smaller and larger tumours respectively with 4.42 (p = 0.001) and with 3.5 months (p = 0.0001) and by radiotherapy respectively with 3.44 and with 3.28 months (p = 0.047 and p = 0.0001).

CONCLUSION

In elderly patients with ATC, although poor prognosis, surgery is still fundamental in the multimodality treatment with significant advantage in selected patients. Nevertheless most of elderly patients with large tumours are suitable only for palliative management.

Ethical issues in the management of thyroid disease

The focus of this article is on clinical ethics issues in the thyroid disease context. Clinical ethics is a subspecialty of bioethics that deals with bedside ethical dilemmas that specifically involve the provider-patient relationship. Such issues include consent and capacity; weighing therapeutic benefits against risks and side-effects; innovative therapies; end of life care; unintended versus intentional harms to patients or patient populations; and healthcare access. This article will review core ethical principles for practice, as well as the moral and legal requirements of informed consent. It will then discuss the range of unique and universal ethical issues and considerations that present in the management of autoimmune thyroid disease and thyroid cancer.

Efficacy of combined treatment for anaplastic thyroid carcinoma: results of a multinstitutional retrospective analysis

INTRODUCTION

Anaplastic thyroid carcinoma (ATC) is a killer tumor, characterized by local invasiveness, risk of recurrence and very poor prognosis. Due to its rarity, clinical case studies concerning management are lacking.

METHODS

We retrospectively reviewed a multinstitutional clinical series of 114 consecutive patients treated between 1996 and 2012 for ATC. The outcomes of a combined treatment were analyzed considering the impact of surgery and radiotherapy on survival.

RESULTS

Patients were divided in groups A and B considering tumor size (tumor lesser and larger than 5 cm). Surgery was carried out in 71 patients, radiotherapy in 89 patients. Tracheostomy and endoprothesis were used respectively in 48.7% and in 25.6% of patients. The mean survival was 5.35 (±3.2) months with no significant difference in group A vs group B. A better survival was observed in both groups of patients undergone a surgical treatment compared to no treated patients (p = 0.001 and p = 0.0001) or to patients undergone radiotherapy alone (p = 0.047 and p = 0.0001). Combination of surgery and radiotherapy significantly improved outcome (p = 0.017).

DISCUSSION

Despite disappointing results from single therapeutic approach, multimodal strategy has progressively become the treatment of choice in ATC, with surgery being the cornerstone of the management.

CONCLUSION

Although dismal prognosis, the combined treatment might significantly improves locoregional disease control, achieving acceptable survival in selected patients and adequate palliation of the symptoms.

BRAF mutations in papillary thyroid carcinoma and emerging targeted therapies (review)

Papillary thyroid carcinoma (PTC) is the most common histotype among the thyroid cancer types. Although PTC is a curable malignancy, many patients relapse after treatment. Thus, there is a need to identify novel factors involved in the pathogenesis of PTC that may be used as targets for new therapies. The MAPK pathway has been implicated in the pathogenesis of PTC. Therefore, in this review, we summarize the role of the BRAF V600E mutation in the development and progression of thyroid cancer. The cinical implication of this molecular abnormality is also discussed. It is evident that the detection of the BRAF V600E mutation is crucial in order to identify novel avenues for thyroid cancer treatment.

Preclinical efficacy of the oncolytic measles virus expressing the sodium iodide symporter in iodine non-avid anaplastic thyroid cancer: a novel therapeutic agent allowing noninvasive imaging and radioiodine therapy

Anaplastic thyroid cancer is an extremely aggressive disease resistant to radioiodine treatment because of loss of sodium iodide symporter (NIS) expression. To enhance prognosis of this fatal cancer, we validated the preclinical efficacy of measles virus (MV)-NIS, the vaccine strain of the oncolytic MV (MV-Edm), modified to include the NIS gene. Western blotting analysis confirmed that a panel of eight anaplastic thyroid cancer (ATC)-derived cell lines do not express NIS protein, but do express CD46, the MV receptor. In vitro cell death assays and in vivo xenograft studies demonstrate the oncolytic efficacy of MV-NIS in BHT-101 and KTC-3, ATC-derived cell lines. Radioactive iodine uptake along with single-photon emission computed tomography (SPECT)-computed tomography imaging of KTC-3 xenografts after (99)Tc(m) administration confirmed NIS expression in vitro and in vivo, respectively, after virus treatment. Adjuvant administration of RAI, to MV-NIS-treated KTC-3 tumors showed a trend for increased tumor cell killing. As current treatment for ATC is only palliative, and MV-NIS is currently Food and Drug Administration approved for human clinical trials in myeloma, our data indicate that targeting ATC with MV-NIS could prove to be a novel therapeutic strategy for effective treatment of iodine-resistant ATC and will expedite its testing in clinical trials for this aggressive disease.

Treatment outcome of patients with anaplastic thyroid cancer: a single center experience

PURPOSE

Anaplastic thyroid cancer is known to have a poor prognosis due to its aggressive and rapid metastasis with median survival of less than 6 months. Multimodal treatment involving surgery and chemoradiotherapy has been used to improve the survival of patients. Here, we retrospectively review of treatment outcome of 13 consecutive patients who were treated at a single center.

MATERIALS AND METHODS

We retrospectively reviewed medical records of 13 anaplastic thyroid cancer patients who received multidisciplinary treatment between 2006 and 2010. Kaplan-Meier survival curve was used to analyze progression-free survival and overall survival of patients.

RESULTS

The median patient age at diagnosis was 69 years, and six patients had stage IVc diseases. Eight patients received primary surgery followed by radiotherapy or concurrent chemoradiotherapy (CCRT). Five patients received weekly doxorubicin-based definitive CCRT, but only one patient's condition remained stable, while the rest experienced rapid disease progression. The median progression-free survival was 2.8 months (95% CI, 1.2-4.4 months), and the median overall survival was 3.8 months (95% CI, 3.0-4.6 months).

CONCLUSION

Patients with anaplastic thyroid cancer showed poor prognosis despite multimodality treatment. Therefore, identification of novel therapeutic targets is warranted to take an effective mode of treatment.

Multifaceted suppression of aggressive behavior of thyroid carcinoma by all-trans retinoic acid induced re-differentiation

Since all-trans retinoic acid (ATRA) has shown promising results in differentiation therapy, the present study was designed to investigate the effects of ATRA on thyroid carcinoma and to evaluate the effectiveness of ATRA in redifferentiation induction of thyroid carcinoma. Therefore, we investigated cell growth rate, morphological and nuclear: cytoplasmic ratio, adherent-dependent growth, response to chemotherapy drug following differentiation, T3 and T4 measurement, and critical genes expression pattern. Papillary cell line showed more growth inhibition by ATRA, in addition, mesenchymal and spindle-shape of 8305C cells changed to polygonal. Additionally, high nuclear: cytoplasmic ratio of anaplastic decreased significantly. Redifferentiation significantly suppressed the anchorage-dependent growth in the both cell lines in a dose-dependent manner, potentiated the arsenic trioxide (ATO) effects in anaplastic and papillary cell lines. Furthermore, reduction in the expression of stemness, and invasion related genes was observed in the both cell lines. Altogether, ATRA treatment could hold the aggressive behavior of thyroid carcinoma in restraint and/or potentiate the effect of chemotherapy drug ATO.

Fungating thyroid cancer: a complex clinical scenario

BACKGROUND

Most research reporting the management of advanced thyroid cancer focuses on major aerodigestive system or vessel involvement. In the present study, we investigated patients with locally advanced thyroid cancers who presented with malignant skin infiltration. The term fungating thyroid cancer (fTC) has been used to describe such a condition.

METHODS

The study was based on prospective collection of clinical, laboratory, imaging, and pathological data of all patients admitted to the head and neck and endocrine surgery unit, Main University Hospital, Alexandria School of Medicine, during the period April 2005-March 2011.

RESULTS

Eleven patients were referred with fTC, eight of whom had undergone subtotal thyroidectomy for an undiagnosed well-differentiated thyroid cancer (DTC) in another institution. The final pathological diagnosis showed (DTC, n = 3), poorly differentiated thyroid cancer (n = 5), anaplastic cancer (n = 2), and medullary thyroid cancer (n = 1). Extensive resections and reconstruction using flaps (pectoralis major, n = 6; deltopectoral, n = 1; sternocleidomastoid, n = 1) were undertaken. Complete tumor clearance (R0) was achieved in one patient and the others had microscopic (R1, n = 6) or macroscopic (R2, n = 1) residual disease. The three patients who did not undergo operation died within one month of presentation. The latest review of the eight patients who did undergo operation ranged from 3 to 6 months, but their survival remains unknown as access for follow-up was limited.

PPARγ Promotes Growth and Invasion of Thyroid Cancer Cells

Undifferentiated (anaplastic) thyroid cancer (ATC) is one of the most aggressive human malignancies and no effective therapy is currently available. We show here that PPARγ levels are elevated in cells derived from ATC. Depletion of PPARγ in HTh74 ATC cells resulted in decreased cell growth, cell cycle arrest and a reduction in pRb and cyclin A and B1 levels. We further showed that both flank and orthotopic thyroid tumors derived from PPARγ-depleted cells grew more slowly than PPARγ-expressing cells. When PPARγ was overexpressed in more differentiated thyroid cancer BCPAP cells which lack PPARγ, there was increased growth and raised pRb and cyclin A and B1 levels. Finally, PPARγ depletion in ATC cells decreased their invasive capacity whereas overexpression in PTC cells increased invasiveness. These data suggest that PPARγ may play a detrimental role in thyroid cancer and that targeting it therapeutically may lead to improved treatment of advanced thyroid cancer.

Epidemiology, clinical presentation, treatment and prognosis of a regional series of 26 anaplastic thyroid carcinomas (ATC). Comparison with the literature

OBJECTIVE

The aim of this study is to retrospectively describe the epidemiological and clinical features, therapeutic modalities, prognostic factors and survival figures in a population of patients with anaplastic thyroid carcinoma (ATC) observed in Auvergne, France. We compared these data with those in the literature.

MATERIAL AND METHODS

The analysis was conducted based on a computer database containing a regional register recorded by health professionals treating ATC.

RESULTS

Of the 1500 cancers observed over 16 years, 26 were identified as ATC. The male/female ratio was 1/2.7 and the average age: 72.1; 76.9% of the cases had thyroid medical history, average tumor size at diagnosis was 7.35 cm with N1 in the course of illness in 61.5% of cases, M1 in 34.6% of cases. Surgery was performed in 84.6% of cases, radiotherapy in 53.8% and chemotherapy in 19.2%. The average survival was 9 months, the survival median: 4 months.

CONCLUSION

Our results show that, in univariate analysis, age above 75, capsular invasion, lymph nodes metastasis, tumor residue after surgery and lack of multimodal treatment (particularly radiotherapy in patients without tumor residue) are factors of poor prognosis. In a multivariate analysis only age above 75, followed by node invasion, capsular invasion, and finally female gender are factors of poor prognosis.

Recent advances in molecular biology of thyroid cancer and their clinical implications

Thyroid cancer is the most common endocrine malignancy. With a rapidly rising incidence in recent years, novel efficient management strategies are increasingly needed for this cancer. Remarkable advances have occurred in understanding several major biologic areas of thyroid cancer, including the molecular alterations for the loss of radioiodine avidity of thyroid cancer, the pathogenic role of the MAP kinase and PI3K/Akt pathways and their related genetic alterations, and the aberrant methylation of functionally important genes in thyroid tumorigenesis and pathogenesis. These exciting advances provide unprecedented opportunities for the development of molecular-based novel diagnostic, prognostic, and therapeutic strategies for thyroid cancer.

Potent inhibition of thyroid cancer cells by the MEK inhibitor PD0325901 and its potentiation by suppression of the PI3K and NF-kappaB pathways

BACKGROUND

We recently demonstrated inhibition of thyroid cancer cells by the MEK inhibitor CI-1040. The objective of this study was to use a potent new-generation MEK inhibitor PD0325901 to further investigate the therapeutic potential of specifically targeting MEK in the MAP kinase pathway for thyroid cancer.

METHODS

We examined the effects of PD0325901 on a variety of cellular and molecular activities of thyroid cancer cell lines with distinct genotypes.

RESULTS

PD0325901 remarkably inhibited MAP kinase pathway signaling in the thyroid cancer cells tested. It potently inhibited cell proliferation (IC(50) = 0.059-0.783 microM) and arrested cell cycle at the G0/G1 phase of cells harboring BRAF or RAS mutations but not cells harboring wild-type alleles or the RET/PTC1 rearrangement. Synergistic inhibitory effects were observed when PD0325901 was combined with phosphatidylinositol 3-kinase (PI3K) or NF-kappaB pathway inhibitors in most cells, including the RET/PTC1-harboring cells. PD0325901 could inhibit invasion and anchorage-independent growth of thyroid cancer cells independently of the type of genetic alterations. This compound did not seem to have significant proapoptotic effects, however.

CONCLUSIONS

The MEK inhibitor PD0325901 has a wide range of potent inhibitory effects on thyroid cancer cells, some of which seemed to be genotype-selective, consistent with the results previously observed with an early-generation MEK inhibitor, CI-1040. The data provide further evidence that targeted inhibition of MEK may be therapeutically effective for thyroid cancer, particularly if the PI3K and NF-kappaB pathways are concurrently inhibited.

Clinical experience of the multimodality management of anaplastic thyroid cancer and literature review

Anaplastic Thyroid Carcinoma (ATC) is a rare thyroid tumor with a very aggressive clinical course. The following is a report of five patients with inoperable locally advanced disease treated at our institution using multimodality management consisting of chemotherapy and hyperfractionated accelerated radiotherapy. A flow diagram with management recommendations for inoperable ATC is suggested.

BRAF mutation in papillary thyroid cancer: pathogenic role, molecular bases, and clinical implications

In recent years, the T1799A B-type Raf kinase (BRAF) mutation in thyroid cancer has received enthusiastic investigation, and significant progress has been made toward understanding its tumorigenic role and clinical significance. Among various thyroid tumors, this mutation occurs uniquely in papillary thyroid cancer (PTC), the most common endocrine malignancy, and some apparently PTC-derived anaplastic thyroid cancers. Many studies have found this mutation to be associated with those clinicopathological characteristics of PTC that are conventionally known to predict tumor progression and recurrence, including, for example, old patient age, extrathyroidal invasion, lymph node metastasis, and advanced tumor stages. Direct association of BRAF mutation with the clinical progression, recurrence, and treatment failure of PTC has also been demonstrated. The BRAF mutation has even been correlated with PTC recurrence in patients with conventionally low-risk clinicopathological factors. Some molecular mechanisms determining BRAF mutation-promoted progression and the aggressiveness of PTC have recently been uncovered. These include the down-regulation of major tumor suppressor genes and thyroid iodide-metabolizing genes and the up-regulation of cancer-promoting molecules, such as vascular endothelial growth factor, matrix metalloproteinases, nuclear transcription factor kappaB, and c-Met. Thus, BRAF mutation represents a novel indicator of the progression and aggressiveness of PTC. Significant advances have also occurred in the preclinical testing of new therapeutic strategies targeting the MAPK pathway aberrantly activated by BRAF mutation and other related mutations. New mitogen extracellular kinase (MEK) inhibitors developed recently are particularly promising therapeutic agents for thyroid cancer. With these advances, it has become clearer that BRAF mutation will likely have significant impact on the clinical management of PTC.

Inhibitory effects of the mitogen-activated protein kinase kinase inhibitor CI-1040 on the proliferation and tumor growth of thyroid cancer cells with BRAF or RAS mutations

CONTEXT

Targeting MAPK kinase (MEK) in the MAPK pathway is a potentially effective therapeutic strategy for thyroid cancer.

OBJECTIVE

The objective of the study was to investigate genotype-dependent therapeutic potential of the MEK inhibitor CI-1040 for thyroid cancer.

EXPERIMENTAL DESIGN

We examined the effects of CI-1040 on proliferation, apoptosis, transformation, thyroid gene reexpression, and xenograft tumor growth with respect to genotypes in 10 thyroid tumor cell lines.

RESULTS

Cell proliferation was potently inhibited by CI-1040 in cells harboring BRAF or RAS mutations but not in cells harboring RET/PTC rearrangement or wild-type alleles. For example, the IC50 values for BRAF mutation-harboring KAT10 cells and DRO cells and H-RAS mutation-harboring C643 cells were 0.365, 0.031, and 0.429 microm, respectively, whereas the IC50 values for RET/PTC1-harboring TPC1 cells and the wild-type MRO and WRO cells were 44, 46, and 278 microm, respectively. Proapoptotic effect of CI-1040 was seen in DRO cells, and cytostatic effect was seen in other cells. Down-regulation of cyclin D1 and reexpression of some thyroid genes were induced by CI-1040 in some BRAF mutation-harboring cells, and transformation was inhibited in all cells. CI-1040 also inhibited the growth of xenograft tumors in nude mice derived from KAT10 or C643 cells but not that derived from MRO cells.

CONCLUSIONS

We for the first time demonstrated potent inhibitory effects of a MEK inhibitor, CI-1040, on thyroid cancer cells, some of which, particularly cell proliferation and tumor growth, seemed to be BRAF mutation or RAS mutation selective. Our data encourage a clinical trial on CI-1040 in thyroid cancer patients.

Lovastatin enhances the replication of the oncolytic adenovirus dl1520 and its antineoplastic activity against anaplastic thyroid carcinoma cells

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive solid tumors and shows morphological features of a highly malignant, undifferentiated neoplasm. Patients with ATC have a poor prognosis with a mean survival time of 2-6 months; surgery, radiotherapy, and chemotherapy do not improve survival. Gene therapy approaches and oncolytic viruses have been tested for the treatment of ATC. To enhance the antineoplastic effects of the oncolytic adenovirus dl1520 (Onyx-015), we treated ATC cells with lovastatin (3-hydroxy-methylglutaryl-CoA reductase inhibitor), a drug used for the treatment of hypercholesterolemia, which has previously been reported to exert growth-inhibitory and apoptotic activity on ATC cells. Lovastatin treatment significantly increased the effects of dl1520 against ATC cells. The replication of dl1520 in ATC cells was enhanced by lovastatin treatment, and a significant increase of the expression of the early gene E1A 13 S and the late gene Penton was observed in lovastatin-treated cells. Furthermore, lovastatin treatment significantly enhanced the effects of dl1520 against ATC tumor xenografts. Lovastatin treatment could be exploited to increase the efficacy of oncolytic adenoviruses, and further studies are warranted to confirm the feasibility of the approach in ATC patients.

Phase II trial of thalidomide for therapy of radioiodine-unresponsive and rapidly progressive thyroid carcinomas

BACKGROUND

There are no known effective therapies for distantly metastatic, rapidly progressive thyroid carcinomas unresponsive to radioiodine.

OBJECTIVE

Since thyroid carcinomas are hypervascular and thalidomide is antiangiogenic, we assessed thalidomide's tumoristatic effects and toxicity in a phase II trial.

DESIGN

Thirty-six patients with follicular, papillary, insular, or medullary thyroid carcinomas and distant, radioiodine-unresponsive metastases (volumes increasing >or= 30% per year before entry) were accrued between July 2001 and December 2002. Daily thalidomide started at 200 mg, increasing over 6 weeks to 800 mg or maximum tolerated dose. Toxicities and responses were assessed at 8-week intervals with tumor volume assessments.

MAIN OUTCOMES

Twenty-eight of 36 patients were evaluable, 5 with partial responses (PR: 18%; 95% confidence interval [95% CI]: 6-37%) and 9 patients with stable disease (SD: 32%; 95% CI: 12-42%) for overall 50% response (95% CI: 31-69%). Median PR duration was 4 months (range: 2-6 months), and SD duration was 6 months (range: 2-14 months). Median survival was 23.5 months for responders (PR + SD) and 11 months for nonresponders. Most frequent toxicity was fatigue (69% grade 1-2, 8% grade 3-4). Four patients had grade 3-4 infections (without neutropenia), one had pericardial effusion, and one had pulmonary embolus.

CONCLUSIONS

Thalidomide confers therapeutic benefit in subsets of thyroid cancer patients with rapidly progressive, distantly metastatic disease.

Reinduction of Cell Differentiation and 131I Uptake in a Poorly Differentiated Thyroid Tumor in Response to the Reverse Transcriptase (RT) Inhibitor Nevirapine

Our recent findings have shown that the reverse transcriptase (RT) inhibitors, nevirapine and efavirenz, used for 10 years in human immunodeficiency virus (HIV) disease, act as cytostatic and differentiating agents by modulating gene expression in several human tumor cell models. In dedifferentiated thyroid cancer, they reestablish thyroid-stimulating hormone (TSH) signaling, Na/I symporter (NIS), thyroglobulin peroxidase (TPO) expression, and even radioiodine uptake (RIU). In this paper, we describe the case of a 76-year-old woman who was affected by thyroid papillary carcinoma and who underwent a total thyroidectomy and a debulking of the right laterocervical region for lymph-node metastases, vessel infiltration, and neoplastic thrombosis of the internal jugular vein, followed by 3 radioiodine treatments. At restaging, a computed tomography scan revealed that distant metastases were mostly not taking up the radioiodine at the 131I whole-body scan (WBS). An analysis of tumor cells obtained by fine-needle aspiration biopsy of a right laterocervical lymph-node revealed cell anisokaryosis, nuclear pleomorphism, and scanty colloid, as well as the undetectable expression of thyroglobulin and NIS proteins. After starting a nevirapine treatment (NT), higher thyroglobulin levels were observed and some metastases exhibited a significant increase in radioiodine uptake, which led us to again treat the patient with 131I. Five (5) months later, the 131I-WBS revealed the disappearance of RIU in some metastases and its significant reduction in other lesions, with a parallel drop in serum thyroglobulin. No new metastatic lesion was revealed by rh-TSH-stimulated 131IWBS and 18F-flourodeoxyglucose positron emission tomography scan. Cells obtained from the right laterocervical lymph-node 2 months after NT exhibited a reduced nuclear pleomorphism, an increase in colloid production, and a significant upregulation of thyroglobulin and NIS protein expression. This first in vivo molecular and morphologic evidence of cell differentiation in human cancer and low toxicity of nevirapine strongly encourage its use in dedifferentiated thyroid cancer treatment.

Gene methylation in thyroid tumorigenesis

Aberrant gene methylation plays an important role in human tumorigenesis, including thyroid tumorigenesis. Many tumor suppressor genes are aberrantly methylated in thyroid cancer, and some even in benign thyroid tumors, suggesting a role of this epigenetic event in early thyroid tumorigenesis. Methylation of some of these genes tends to occur in certain types of thyroid cancer and is related to specific signaling pathways. For example, methylation of PTEN and RASSF1A genes occurs mostly in follicular thyroid cancer, and its tumorigenic role may be related to the phosphatidylinositol 3-kinase/Akt signaling pathway, whereas methylation of genes for tissue inhibitor of metalloproteinase-3, SLC5A8, and death-associated protein kinase occurs in papillary thyroid cancer and is related to the BRAF/MAPK kinase/MAPK pathway. Methylation of thyroid-specific genes, such as those for sodium/iodide symporter and thyroid-stimulating hormone receptor, is also common in thyroid cancer. Although its tumorigenic role is not clear, methylation, and hence silencing, of these thyroid-specific genes is a cause for the failure of clinical radioiodine treatment of thyroid cancer. Unlike gene methylation, histone modifications have been relatively poorly investigated in thyroid tumors. Future studies need to emphasize the mechanistic aspects of these two types of epigenetic alterations to uncover new molecular mechanisms in thyroid tumorigenesis and to provide novel therapeutic targets for thyroid cancer.

Dermatologic aspects of thyroid disease

Thyroid disorders commonly have dermatologic manifestations. The purpose of the present chapter is to review and emphasize potential clinical dermatologic findings that can occur with Graves' disease, hypothyroidism and thyroid cancer. In autoimmune diseases such as Graves' disease and Hashimoto's thyroiditis the skin manifestations may be related to either thyroid hormone levels themselves or to the associated T and/or B cell abnormalities. Thyroid cancer may be associated with various syndromes that could have significant skin manifestations.

Peroxisomal proliferator-activated receptor-gamma agonists induce partial reversion of epithelial-mesenchymal transition in anaplastic thyroid cancer cells

Anaplastic thyroid cancer (ATC) is an extremely aggressive tumor characterized by marked epithelial mesenchymal transition, which leads, almost invariably, to death. Peroxisomal proliferator-activated receptor (PPAR)-gamma agonists have recently emerged as potential antineoplastic drugs. To establish whether ATC could be a target of PPAR gamma agonists, we first examined PPAR gamma protein expression in a panel of six ATC cell lines and then studied the biologic effects of two PPAR gamma agonists, ciglitazone and rosiglitazone, that belong to the class of thiazolidonediones. PPAR gamma protein was present and functional in all ATC cell lines. Both ciglitazone and rosiglitazone showed complex biological effects in ATC cells, including inhibition of anchorage-dependent and -independent growth and migration, and increased apoptosis rate. Rosiglitazone-induced growth inhibition was associated with cell cycle arrest and changes in cell cycle regulators, such as an increase of cyclin-dependent kinases inhibitors p21(cip1) and p27(kip1), a decrease of cyclin D1, and inactivation of Rb protein. Rosiglitazone-induced apoptosis was associated with a decrease of Bcl-X(L) expression and caspase-3 and -7 activation. Moreover, rosiglitazone antagonized IGF-I biological effects by up-regulating phosphatase and tensin homolog deleted from chromosome 10 with subsequent inhibition of the phosphatidylinositol 3-kinase/Akt signaling pathway. Finally, rosiglitazone increased the expression of thyroid-specific differentiation markers. In conclusions, these data suggest that PPAR gamma agonists induce a partial reversion of the epithelial mesenchymal transition in ATC cells by multiple mechanisms. PPAR gamma agonists may, therefore, have a role in the multimodal therapy currently used to slow down ATC growth and dissemination.

[Anaplastic thyroid carcinoma]

Well-differentiated thyroid carcinoma (TC), as papillary and follicular carcinoma, usually follows a relatively benign course after total thyroidectomy and thyroid remnant ablation with 131I. In contrast, anaplastic TC or undifferentiated TC, also derived from the thyroid follicular epithelium, refers to one of the more aggressive human malignancies, which have lost most or all characteristics of the tissue from which it originated. Rapid tumor growth presages early mortality unless combined therapy is aggressively pursued. Definitive curative approach does not exist for most patients. The best approach is still aggressive surgery combined with the associated use of new chemotherapies associated with local external beam radiotherapy.

Evidence for transcriptional and posttranscriptional alterations of the sodium/iodide symporter expression in hypofunctioning benign and malignant thyroid tumors

The uptake of iodide by epithelial thyroid cells requires the expression of a specific transporter, the Na(+)/I(-) symporter, NIS. Benign and malignant thyroid tumors of epithelial origin show a decrease up to a loss of iodide uptake activity. Previous studies of the human NIS (hNIS) gene expression in these tumors, based on the amplification of transcripts and/or immunohistochemical detection of the protein, have yielded divergent data; hNIS expression was found either increased or decreased. To get a new and integrated view of the alterations of hNIS expression in hypofunctioning thyroid tumors, we performed investigations of hNIS transcript and hNIS protein levels on the same tumors and paired normal tissue samples. HNIS, identified as a 75- to 80-kd species, was present in all normal tissue samples from euthyroid patients, but was undetectable, even at high membrane protein input, in all benign and malignant hypofunctioning thyroid tumors. By contrast, approximately 50% of tumors contained hNIS transcripts. This dissociation between transcript and protein levels was not found for the transcript and protein encoded by the PDS gene assayed in the same tumors. The hNIS transcript-positive tumors contained small amounts of low-molecular mass hNIS-immunoreactive species identified as nonglycosylated hNIS. Tumors containing the nonmature form of hNIS exhibited a predominant intracellular immunolabeling. In conclusion, our data show that benign and malignant hypofunctioning thyroid tumors either no longer express hNIS protein or express only a very low amount of nonglycosylated hNIS and indicate that the impairment of hNIS gene expression might result from alterations at both transcriptional and posttranscriptional levels.

Thyroglobulin: a specific serum marker for the management of thyroid carcinoma

Thyroglobulin measurements in tissue and serum play an integral role in the evaluation of patients who have thyroid cancer. Immunohistochemical detection of thyroglobulin in surgical specimens is useful in the differential diagnosis of tumors of unknown origin; however, the most important application of thyroglobulin measurement in clinical practice is in the postsurgical management of differentiated thyroid cancer. Serum thyroglobulin is a highly specific and sensitive tumor marker for detecting persistent or recurrent thyroid cancer and for monitoring clinical status. The reappearance of circulating thyroglobulin after total thyroid ablation is pathognomonic for the presence of tumor. The measurement of thyroglobulin in serum is challenging, however, and several analytical problems limit assay performance. Thyroglobulin autoantibody interference is a particularly significant concern that requires all thyroglobulin samples to be screened for their presence. No immunoassay is totally free from interference by thyroglobulin autoantibodies. Measurement of thyroglobulin mRNA to detect circulating tumor cells may help to overcome some of the limitations of current protein-detection methods; serum thyroglobulin will continue to remain the "gold standard." The complex functional features of thyroid carcinomas make sole reliance upon any one diagnostic technique, including thyroglobulin assessments, potentially misleading. Thyroglobulin measurements are a critical component of a multifaceted diagnostic approach to this disease.

Diagnostic value of serum thyroglobulin measurements in the follow-up of differentiated thyroid carcinoma, a structured meta-analysis

OBJECTIVE

To investigate to what extent thyroid remnant ablation and withdrawal from thyroxine are required to achieve sufficient accuracy of serum thyroglobulin (Tg) measurements as an indicator of tumour recurrence in the follow-up of patients with differentiated thyroid carcinoma.

DESIGN AND METHODS

We conducted a meta-analysis of the literature from 1975 to 2003 on serum Tg measurements in the follow-up of differentiated thyroid carcinoma. In a computer-based search, we initially found 915 articles that were finally narrowed down to 120. These 120 papers were subjected to strict in/and exclusion criteria, leaving 46 articles (totalling 9094 patients). Data from these articles were extracted in a structured fashion and were grouped according to initial therapy, TSH status, Tg assay method and definition of a 'gold standard'. Original 2 x 2 tables were pooled by summary receiver operating characteristic curve analysis (sROCa), best estimates of sensitivity and specificity being obtained by the combination of sROCa and Mantel-Haenszel odds ratios.

RESULTS

Despite considerable differences between series in laboratory and clinical methodology, we consistently found higher specificity for Tg measurements after thyroid remnant ablation than after surgery alone. Highest pooled sensitivity 0.961 +/- 0.013 (SE) was found for immunometric assay (IMA) after thyroid remnant ablation and thyroid hormone withdrawal, at a specificity of 0.947 +/- 0.007. Pooled sensitivity decreased significantly if ablated patients were tested while on thyroid hormone (0.778 +/- 0.023, at a specificity of 0.977 +/- 0.005). Significantly decreased pooled specificity was found in patients who did not undergo remnant ablation (sensitivity 0.972 +/- 0.023, at a specificity of 0.759 +/- 0.028). If recombinant human TSH (rhTSH) stimulation was used as a substitute for thyroxine withdrawal, sensitivity remained high (0.925 +/- 0.018) while specificity decreased to 0.880 +/- 0.013. In all analyses, specificity of Tg would decrease when unspecified activity in the thyroid region at scintigraphy was considered benign, whereas sensitivity decreased when such activity was considered malignant.

CONCLUSION

This study confirms that the best accuracy of Tg-guided follow-up in patients treated for differentiated thyroid carcinoma is obtained if treatment includes remnant ablation, and Tg testing is performed while off thyroxine.

Modern Management of Differentiated Thyroid Cancer

The outcome in differentiated thyroid cancer is excellent. Simple prognostic factors, including the age of the patient at diagnosis, the size of the primary cancer, completeness of surgical excision, and the presence of distant metastases, allow the clinician to judge how a patient will do. The preferred treatment is total thyroidectomy and in selected patients radioactive iodine can be used to ablate residual thyroid or functioning metastases in lymph nodes and distant sites. The physician has two excellent methods for following the patient: the whole-body scan with radionuclides of iodine, and measurement of serum thyroglobulin. In patients with elevated thyroglobulin and negative scans with radioactive iodine, there is increasing evidence that positron emission tomography (PET) is helpful in locating the site of thyroglobulin production.

Histological study of papillary thyroid carcinoma treated with percutaneous ethanol injection therapy

An 86-year-old male patient was treated by percutaneous ethanol injection therapy (PEIT), following tumorectomy of a papillary thyroid carcinoma and a modified radical neck dissection for its metastasis. After seven treatments with PEIT, the patient was admitted to hospital for a tracheotomy to treat progressive severe dyspnea. Seven days later the patient died from acute renal failure caused by diabetic ketoacidosis. At autopsy, tumor masses were found to comprise mostly scar tissue, and the remaining neoplastic cells often showed anaplastic changes. Fresh coagulation necrosis and hemorrhages were scattered throughout the tumor lesions and their microvessels were occasionally occluded by thrombus. These changes were seen prominently, especially at the central areas of PEIT treatment. Given these findings, we believe that PEIT may be useful in providing local control for the progression of thyroid cancer, especially in cases of unresectable malignant thyroid tumors.