EVOLUTION OF TARGETED THERAPIES FOR THYROID CARCINOMA.

Although treatment options for patients with advanced and metastatic thyroid carcinoma were historically limited, developments in the past 15 years in understanding the pathogenesis of these malignancies have permitted identification of novel targeted therapies to improve outcomes. Five individual drugs and one combination therapy have achieved regulatory approval since 2011, all showing improvements in progression-free survival or high response rates. More selective targeting of mutated oncogenic kinases is leading to increasing efficacy with fewer toxicities, at least in early human trials. Collaborations among endocrinologists, medical oncologists, and patients are making advances possible, where such developments appeared impossible merely 15 years ago.

Embolization of iliac metastasis during lenvatinib treatment in patient with advanced Hürthle cell thyroid carcinoma.

Lenvatinib is a tyrosine kinase inhibitor (TKI) with antiproliferative and antiangiogenic effects indicated for the treatment of progressive, locally advanced or metastatic progressive thyroid carcinoma, refractory to radioactive iodine therapy. Antiangiogenic therapies induce ischemic necrosis of tumor tissue, with increased risk of hemorrhagic complications. The management of hemorrhagic risk is based on precautionary measures and for any surgical procedure, it is advised to interrupt the treatment in order to avoid complications. 'Flare-up' of tumor activity may follow TKI interruption. However, it is not known if continuing TKIs during minimally invasive interventions is safe. We report here the first case in which an embolization of metastasis is performed without interrupting lenvatinib treatment. The procedure was successful and free of complications.

Panniculitis Under Successful Targeted Inhibition of the MAPK/ERK Signaling Pathway in a Patient With BRAF V600E-mutated Spindle Cell Oncocytoma of the Pituitary Gland.

BACKGROUND: Spindle cell oncocytoma (SCO) is a rare non-neuroendocrine neoplasm of the pituitary gland. In general, surgical excision and radiation therapy is performed. However, local recurrences are frequently seen, requiring repeated surgical and radio-oncological interventions. Thus, mutational analysis of the tumor and targeted therapy may represent a valuable therapy option in these patients. CASE REPORT: A 38-year-old female patient with past medical history of 6 surgeries (two transsphenoidal and four transcranial), radiation therapy, and chemoradiation therapy due to several recurrences of a SCO, presented for follow-up imaging. MRI of the brain showed growth of a tumor in the right parasellar region consistent with a new local recurrence, which due to its size and location was considered to be not resectable. Molecular analysis of a previously surgically removed tumor showed a BRAF V600E mutation and thus, combined targeted inhibition of the MAPK/ERK signaling pathway using a BRAF inhibitor and a MEK inhibitor was started. Due to drug-induced panniculitis, MEK inhibitor had to be stopped and BRAF inhibitor only was continued, which was well tolerated by the patient. Subsequent imaging revealed tumor regression already four weeks after therapy initiation and no disease progression has been observed to date. CONCLUSION: A SCO patient with BRAF V600E mutation was successfully treated using targeted inhibition of the MAPK/ERK signaling pathway. Under therapy, tumor regression was observed and the patient has been free of progressive disease for more than two years now. Thus, mutational analysis and targeted inhibition may offer an effective treatment option for SCO patients, while potential side-effects to this therapy, like observed in our case, can occur and needs to be adequately treated.

Phase 2 study of vascular endothelial growth factor trap for the treatment of metastatic thyroid cancer.

BACKGROUND: Several multitargeted tyrosine kinase inhibitors (TKIs) have demonstrated activity in patients with thyroid cancer that is refractory to radioactive iodine (RAI). The antitumor effect is attributed at least in part to the ability of these TKIs to inhibit angiogenesis in these vascular tumors. Vascular endothelial growth factor (VEGF) Trap (VT) is a recombinantly produced fusion protein consisting solely of human sequences for VEGF receptors 1 and 2 extracellular domains and human immunoglobulin 1. Evaluating VT in patients with thyroid cancer is reasonable considering the activity observed with TKIs targeting VEGF. METHODS: The current study was a single-institution, phase 2, Simon 2-stage design (21 to >41 patients) study based on the objective response rate and/or 6-month progression-free survival as the primary endpoints. Eligible patients were required to have progressive, RAI-refractory and/or [18 F]fludeoxyglucose-avid, recurrent and/or metastatic, nonmedullary, nonanaplastic thyroid cancer; disease that was measurable using Response Evaluation Criteria In Solid Tumors (RECIST) criteria; and adequate organ and bone marrow function. VT at a dose of 4 mg/kg intravenously was administered every 14 days. RESULTS: A total of 40 patients were included in the analysis. Of these patients, 24 had papillary thyroid cancer, 2 had follicular thyroid cancer, and 11 had Hurthle cell thyroid cancer. The final 3 tumors were classified as poorly differentiated. There were no complete and/or partial responses noted; 34 patients achieved stable disease and 6 patients experienced disease progression as their best response. Of the 34 patients with stable disease, 16 remained on the study for >6 months and 6 patients remained on the study for >12 months. The median duration on treatment was 4.1 months (range, 0.6-30.8 months). CONCLUSIONS: Unlike TKIs, which have shown responses in this setting, to the authors' knowledge there have been no responses observed with the use of single-agent VT to date. It does not appear to be a promising drug for the treatment of patients with thyroid cancer.

Inducing cancer indolence by targeting mitochondrial Complex I is potentiated by blocking macrophage-mediated adaptive responses.

Converting carcinomas in benign oncocytomas has been suggested as a potential anti-cancer strategy. One of the oncocytoma hallmarks is the lack of respiratory complex I (CI). Here we use genetic ablation of this enzyme to induce indolence in two cancer types, and show this is reversed by allowing the stabilization of Hypoxia Inducible Factor-1 alpha (HIF-1α). We further show that on the long run CI-deficient tumors re-adapt to their inability to respond to hypoxia, concordantly with the persistence of human oncocytomas. We demonstrate that CI-deficient tumors survive and carry out angiogenesis, despite their inability to stabilize HIF-1α. Such adaptive response is mediated by tumor associated macrophages, whose blockage improves the effect of CI ablation. Additionally, the simultaneous pharmacological inhibition of CI function through metformin and macrophage infiltration through PLX-3397 impairs tumor growth in vivo in a synergistic manner, setting the basis for an efficient combinatorial adjuvant therapy in clinical trials.

Hürthle Cell Carcinoma in a Lingual Thyroid.

OBJECTIVE: To present a case of lingual thyroid Hürthle cell carcinoma (HCC). CLINICAL PRESENTATION AND INTERVENTION: A 37-year-old female presented with dysphagia and recurrent haemorrhage. Histopathology was suggestive of HCC; the tumour was excised by the trans-glossal approach which provided adequate exposure and helped avert external scarring or mandibular osteotomy. Histopathology showed a tumour-positive right lateral resection margin. This prompted referral to nuclear medicine for radio-iodine ablation. CONCLUSION: Lingual thyroid cases should be followed up closely and fine-needle aspiration biopsy should be considered when in doubt.

Pioglitazone Therapy of PAX8-PPARγ Fusion Protein Thyroid Carcinoma.

Context: A subset of thyroid carcinomas expresses an oncogenic paired box 8 (PAX8) and peroxisome proliferator activated receptor γ (PPARγ) fusion protein (PPFP). The PPARγ/PPFP ligand pioglitazone is highly therapeutic in a transgenic mouse model of PPFP thyroid carcinoma, but whether pioglitazone is therapeutic in patients with PPFP thyroid carcinoma is unknown. Case Description: Tumor blocks from 40 patients with progressive thyroid cancer despite standard-of-care therapy were screened for PPFP, and the tumor from only one patient (2.5%) was positive. The patient had a 6.0-cm acetabular soft tissue metastasis from Hürthle cell carcinoma that caused severe pain on weight bearing and had a serum thyroglobulin level of 1974 ng/mL. After 24 weeks of therapy with pioglitazone, the metastatic lesion was 3.9 cm, the thyroglobulin level was 49.4 ng/mL, and the patient was pain-free. Thirteen months after discontinuation of pioglitazone, the metastatic lesion was 3.6 cm, the thyroglobulin level was 4.7 ng/mL, and the patient remained pain-free. Conclusions: Pioglitazone may be therapeutic in patients with PPFP thyroid cancer. However, thyroid cancers that are progressive despite standard-of-care therapy appear to only rarely express PPFP.

Tyrosine kinase inhibitors in iodine-refractory differentiated thyroid cancer: experience in clinical practice.

PURPOSE: The aim of this study is to describe our clinical experience with tyrosine kinase inhibitors (TKIs) and to evaluate their efficacy and tolerability in patients with iodine-refractory differentiated thyroid cancer (DTC). METHODS: There were 17 patients (47.1% women, mean age: 65.7) with DTC iodine-refractory (9 papillary, 2 follicular and 3 Hürthle cell), treated with TKIs: 16 with sorafenib and 1 with lenvatinib as first-line treatment; 7 required second-line treatment (4 lenvatinib and 3 axitinib). Primary endpoints were progression-free survival (PFS) and radiographic response (determinate at 3, 6, 12, 18, and 24 months after the initiation of treatment) and second endpoints were determining differences in baseline characteristics depending on clinical course and describing toxicities and tolerability. RESULTS: Median PFS was 18 months. During the first 24 months of treatment with TKIs PR rate was 35.3% (only 5.8% ≥ 6 months) and SD ≥ 6 months was observed in 58.8%. There were no significant differences in baseline characteristics between patients with good and poor evolution. Adverse events (AEs) were present in 100% of patients, but most of them were grade 1 and 2. CONCLUSIONS: In our population of patients with iodine-refractory DTC, treatment with sorafenib, lenvatinib, and axitinib allows the stabilization of the disease in a high percentage of cases, with acceptable tolerability.

Molecular and metabolic features of oncocytomas: Seeking the blueprints of indolent cancers.

Oncocytic tumors are a peculiar subset of human neoplasms in which mitochondria have been proven to have a prominent role. A number of paradoxes render these clinical entities interesting from the translational research point of view. Most oncocytic tumors are generally metabolically constrained due to the impaired respiratory capacity and lack of the ability to respond to hypoxia, yet they maintain features that allow them to strive and persist in an indolent form. Their unique molecular and metabolic characteristics are an object of investigation that may reveal novel ways for therapeutic strategies based on metabolic targeting. With this aim in mind, we here examine the current knowledge on oncocytomas and delve into the molecular causes and consequences that revolve around the oncocytic phenotype, to understand whether we can learn to design therapies from the dissection of benign neoplasms. This article is part of a Special Issue entitled Mitochondria in Cancer, edited by Giuseppe Gasparre, Rodrigue Rossignol and Pierre Sonveaux.

Safety and tolerability of sorafenib in patients with radioiodine-refractory thyroid cancer.

Effective adverse event (AE) management is critical to maintaining patients on anticancer therapies. The DECISION trial was a multicenter, randomized, double-blind, placebo-controlled, Phase 3 trial which investigated sorafenib for treatment of progressive, advanced, or metastatic radioactive iodine-refractory, differentiated thyroid carcinoma. Four hundred and seventeen adult patients were randomized (1:1) to receive oral sorafenib (400 mg, twice daily) or placebo, until progression, unacceptable toxicity, noncompliance, or withdrawal. Progression-free survival, the primary endpoint of DECISION, was reported previously. To elucidate the patterns and management of AEs in sorafenib-treated patients in the DECISION trial, this report describes detailed, by-treatment-cycle analyses of the incidence, prevalence, and severity of hand-foot skin reaction (HFSR), rash/desquamation, hypertension, diarrhea, fatigue, weight loss, increased serum thyroid stimulating hormone, and hypocalcemia, as well as the interventions used to manage these AEs. By-cycle incidence of the above-selected AEs with sorafenib was generally highest in cycle 1 or 2 then decreased. AE prevalence generally increased over cycles 2-6 then stabilized or declined. Among these AEs, only weight loss tended to increase in severity (from grade 1 to 2) over time; severity of HFSR and rash/desquamation declined over time. AEs were mostly grade 1 or 2, and were generally managed with dose interruptions/reductions, and concomitant medications (e.g. antidiarrheals, antihypertensives, dermatologic preparations). Most dose interruptions/reductions occurred in early cycles. In conclusion, AEs with sorafenib in DECISION were typically grade 1 or 2, occurred early during the treatment course, and were manageable over time.

Optimizing therapy for radioactive iodine-refractory differentiated thyroid cancer: current state of the art and future directions.

The majority of patients with differentiated thyroid cancer are cured with standard primary treatments including surgery, radioactive iodine and TSH suppression. A small proportion of patients who develop radioactive iodine-refractory metastatic disease have few treatment options. Recent discovery of the molecular mechanisms that contribute to thyroid cancer tumorigenesis and its progression have revealed key targets that are currently being evaluated in clinical trials. In the last decade several novel targeted therapies have shown encouraging results and have brought hope to patients with advanced disease. However, identifying the subpopulation of patients who may benefit from systemic therapies remains a challenge as the use of these therapeutic modalities is associated with high toxicity rates and most patients have a long indolent phase where the tumor is stable or slowly progressive and asymptomatic. The objective of this review is to summarize the management of patients with metastatic, radioactive iodine refractory differentiated thyroid cancer.

Motesanib diphosphate in progressive differentiated thyroid cancer.

BACKGROUND: The expression of vascular endothelial growth factor (VEGF) is characteristic of differentiated thyroid cancer and is associated with aggressive tumor behavior and a poor clinical outcome. Motesanib diphosphate (AMG 706) is a novel oral inhibitor of VEGF receptors, platelet-derived growth-factor receptor, and KIT. METHODS: In an open-label, single-group, phase 2 study, we treated 93 patients who had progressive, locally advanced or metastatic, radioiodine-resistant differentiated thyroid cancer with 125 mg of motesanib diphosphate, administered orally once daily. The primary end point was an objective response as assessed by an independent radiographic review. Additional end points included the duration of the response, progression-free survival, safety, and changes in serum thyroglobulin concentration. RESULTS: Of the 93 patients, 57 (61%) had papillary thyroid carcinoma. The objective response rate was 14%. Stable disease was achieved in 67% of the patients, and stable disease was maintained for 24 weeks or longer in 35%; 8% had progressive disease as the best response. The Kaplan-Meier estimate of the median duration of the response was 32 weeks (the lower limit of the 95% confidence interval [CI] was 24; the upper limit could not be estimated because of an insufficient number of events); the estimate of median progression-free survival was 40 weeks (95% CI, 32 to 50). Among the 75 patients in whom thyroglobulin analysis was performed, 81% had decreased serum thyroglobulin concentrations during treatment, as compared with baseline levels. The most common treatment-related adverse events were diarrhea (in 59% of the patients), hypertension (56%), fatigue (46%), and weight loss (40%). CONCLUSIONS: Motesanib diphosphate can induce partial responses in patients with advanced or metastatic differentiated thyroid cancer that is progressive. (ClinicalTrials.gov number, NCT00121628.)

A phase II study of gefitinib in patients with advanced thyroid cancer.

OBJECTIVE: To determine the efficacy of gefitinib in patients with advanced thyroid cancer. DESIGN: In this open-label phase II trial, 27 patients with radioiodine-refractory, locally advanced, or metastatic thyroid cancer were treated with 250 mg of daily gefitinib. Histologic subtypes included papillary (41%), follicular (22%), anaplastic (19%), medullary (15%), and Hürthle cell carcinomas (4%). The primary endpoint was overall response rate. Secondary endpoints were toxicity, progression-free survival (PFS), and overall survival (OS). MAIN OUTCOMES: There were no objective responses among the 25 patients evaluated. After 3, 6, and 12 months of treatment, 48%, 24%, and 12% of patients had stable disease (SD), respectively. Median PFS and OS were 3.7 and 17.5 months, respectively. Five patients with SD had a decrease in thyroglobulin (Tg) to <90% of baseline that was maintained for at least 3 months. CONCLUSIONS: Although gefitinib therapy did not result in any tumor responses, 32% of patients had reductions in tumor volume that did not meet criteria for partial response rate. Along with falling Tg levels and prolonged SD in a subset of patients, this may indicate biologic activity.

Advances in the medical management of differentiated thyroid carcinoma and their impact on the surgical approach.

The introduction of recombinant human TSH and neck ultrasonography has refined the management of differentiated thyroid cancer, leading to the publication of new guidelines by the American Thyroid Association (ATA) and a consensus report by the European Thyroid Association (ETA) in 2006. In this paper, we give an overview of the current medical management of differentiated thyroid cancer (pre-surgical, post-surgical), of how the advances have been integrated into the recent 2006 ATA guidelines and ETA consensus and finally, of the impact on the surgical management (first surgery, treatment of cervical lymph nodes) of differentiated thyroid cancer.

Carcinoma de células de Hürthle. Descripción de dos casos intervenidos y revisión de la literatura / Hürthle cells carcinoma. Report of two operated cases and review of the literature

Los carcinoma s de células de Hürthle están considerados como variantes de los carcinomas foliculares y representan alrededor del 2% de todos los tumores malignos de la glándula tiroides. Presentamos 2 casos clínicos correspondientes a dos mujeres de 46 y 43 años confirmados mediante estudio histológico tras tiroidectomía total con buena evolución postoperatoria. La presencia de invasión capsular y vascular es el criterio más importante para diferenciar esta entidad de los adenomas de células de Hürthle

Hürthle cells carcinomas are considered as a variant of folicular carcinomas and represent about 2% of all malignant thyroid tumours. We report 2 cases of 2 women of 46 and 43 years old confirmed by histological exam after total thyroidectomy with good postoperative evolution. The presence of capsular and vascular invasion is the most important criteria to distinguish this entity from the Hürthle cells adenomas

Prognostic factors in patients with Hürthle cell neoplasms of the thyroid.

BACKGROUND: Hürthle cell neoplasms, often considered a variant of follicular thyroid neoplasms, represent 3% of thyroid carcinomas. Only a handful of publications have focused on the biologic behavior, prognostic factors, and treatment outcomes of Hürthle cell carcinoma. The objective of the current study was to identify the clinical and pathologic features of Hürthle cell carcinomas that predict disease progression or death. METHODS: The authors reviewed medical records of patients who were treated for Hürthle cell carcinoma (HCC) and Hürthle cell adenoma (HCA) at The University of Texas M. D. Anderson Cancer Center from March 1944 to February 1995, including follow-up information. The pathologic diagnosis was confirmed by one of the authors. RESULTS: The authors identified 127 patients with Hürthle cell neoplasms, 89 patients with HCC and 38 patients with HCA. Seven patients with HCC had foci of anaplastic thyroid carcinoma. Survival for this subgroup was worse compared with the overall group and was analyzed separately. The HCC group was significantly older (age 51.8 years vs. age 43.1. years) and had larger tumors (4.3 cm vs. 2.9 cm) compared with the HCA group. No differences were seen in gender or previous radiation exposure. Forty percent of patients in the HCC group died of thyroid carcinoma, whereas no patients in the HCA group died of the disease. There has been no improvement in all-cause and disease specific mortality in the past 5 decades for patients with these neoplasms. Conventional staging systems predicted mortality with minor differences. Of the patients with known metastasis, 38% showed radioiodine uptake. Univariate analysis identified older age, higher disease stage, tumor size, extraglandular invasion, multifocality, lymph node disease, distant metastasis, extensive surgery, external beam radiation therapy, and chemotherapy as factors that were associated with decreased survival. Tumor encapsulation was associated with improved survival. Although radioactive iodine treatment had no overall effect on survival, subgroup analysis showed that patients who received radioactive iodine for adjuvant ablation therapy had better outcomes compared either with patients who did not receive radioactive iodine or with patients who received radioactive iodine as treatment for residual disease. Multivariate analysis indicated that older age and larger tumor size predicted worse survival through an association with worse behaving tumors (multifocal, less encapsulated, and with extraglandular invasion). The decreased survival in patients with lymph node metastases may be explained by its association with distant metastases. The association of extensive surgery, external beam radiation therapy, and chemotherapy with worse survival also disappeared once those factors were analyzed together with other prognostic factors, such as distant metastases. CONCLUSIONS: Several clinical and pathologic prognostic factors were identified in patients with HCC and HCA. Older age and larger tumor size predicted reduced survival. Radioactive iodine therapy may confer a survival benefit when it is used for adjuvant ablation therapy, but not when residual disease is present. The authors could not demonstrate a survival benefit for the use of extensive surgery, external beam radiation therapy, or chemotherapy.

[Increase in TSH levels in thyroid carcinoma patients after withdrawal of suppressive levothyroxine medication]. / Anstieg des TSH-Spiegels bei Schilddrüsenkarzinompatienten nach Entzug einer suppressiven Levothyroxinmedikation.

AIM: In 76 patients with thyroid carcinoma (60 f., 16 m.; age 51 +/- 15 years; 52 with papillary, 22 with follicular, 2 with Hürthle cell thyroid carcinoma), three different schemes to withdraw LT4 before 131I whole body scintigraphy were compared. METHOD: In scheme I no interval LT3 medication is applied. Scheme II starts one week after withdrawal of LT4 with a two weeks lasting LT3 medication: 40-80 micrograms LT3/die in the first week and 20 micrograms LT3/die in the second week. Afterwards no further LT3 medication is given. Scheme III is identical to scheme II in the first three weeks but 20 micrograms LT3 medication is continued until 131I-application. Retrospectively 121 studies were evaluated concerning the scheme specific increase of TSH. Factors which may influence the increase of TSH were analysed, i.e. age, sex, thyreoglobuline, LT4 dose, duration of LT4 treatment, histological type of carcinoma, result of 131I whole body scanning. RESULTS: There was a significant relation between increase of TSH and the applied scheme. Schemes with interval LT3 medication are more comfortable for the patient but time to stimulate TSH to values > or = 30 microIU/ml is prolonged, especially using scheme III. Female patients needed a significantly longer time compared to male patients to reach a TSH value > or = 30 microIE/ml. Concerning repetitive withdrawal of LT4, there was a fair intraindividual reproducibility of the time period from LT4 withdrawal to TSH values > or = 30 microIE/ml. CONCLUSION: Every scheme has its specific field of indication depending on the compliance of the patients.