Long-term follow-up of patients with bone metastases from differentiated thyroid carcinoma -- surgery or conventional therapy?

Surgical management of appendicular skeletal metastases in thyroid carcinoma

Background. Bone is a frequent site of metastasis from thyroid carcinoma, but prognostic factors for patients who have surgery for thyroid carcinoma bone metastases are poorly understood. Methods. A retrospective review at a single institution identified 41 patients that underwent surgery in the appendicular skeleton for thyroid carcinoma bone metastasis from 1988 to 2011. Results. Overall patient survival probability by Kaplan-Meier analysis after surgery for bone metastasis was 72% at 1 year, 29% at 5 years, and 20% at 8 years. Patients who had their tumor excised (P = 0.001) or presented with solitary bone involvement had a lower risk of death following surgery adjusting for age and gender. Disease progression at the surgery site occurred more frequently with a histological diagnosis of follicular carcinoma compared with other subtypes (P = 0.023). Multivariate analysis showed that tumor subtype, chemotherapy, and preoperative radiation treatment had no effect on survival after surgery. Patients treated with radioactive iodine had better survival following thyroidectomy, but not following surgery for bone metastases. Conclusions. For patients undergoing surgery for thyroid cancer bone metastasis, resection of the bone metastasis, if possible, has a survival benefit.

Skull metastasis in papillary carcinoma of thyroid: A case report

Papillary thyroid carcinoma with metastasis to the skull is extremely rare. We report a case of unsuspected papillary thyroid carcinoma with skull metastasis. A 48-year-old female patient presenting with painless, pulsatile, progressively increasing swelling in the occipitoparietal region of the scalp approached for an X-ray of the skull. Ultrasound of palpable swelling in the neck revealed a heteroechoic lesion with increased vascularity. Foci of calcification were seen involving both lobes of the thyroid. Ultrasound of scalp showed a destructive mass in the skull with increased vascularity. Biopsy of thyroid lesions revealed branching papillae having a dense fibrovascular core covered by cuboidal epithelial cells with nuclei having a clear ground glass appearance. This case illustrates how isolated extensive skull metastasis can be found in papillary carcinoma patients without causing significant morbidity. Therefore, in the clinical course of thyroid papillary carcinoma, skull metastasis should be considered, and the patients should be meticulously investigated and followed up.

Spinal metastasis in thyroid cancer

BACKGROUND

Thyroid carcinoma generally responds well to treatment and spinal metastasis is an uncommon feature. Many studies have looked at the management of spinal metastasis and proposed treatments, plans and algorithms. These range from well-established methods to potentially novel alternatives including bisphosphonates and vascular endothelial growth factor (VEGF) therapy, amongst others.The purposes of this systematic review of the literature are twofold. Firstly we sought to analyse the proposed management options in the literature. Then, secondly, we endeavoured to make recommendations that might improve the prognosis of patients with spinal metastasis from thyroid carcinomas.

METHODS

We conducted an extensive electronic literature review regarding the management of spinal metastasis of thyroid cancer.

RESULTS

We found that there is a tangible lack of studies specifically analysing the management of spinal metastasis in thyroid cancer. Our results show that there are palliative and curative options in the management of spinal metastasis, in the forms of radioiodine ablation, surgery, selective embolisation, bisphosphonates and more recently the VEGF receptor targets.

CONCLUSIONS

The management of spinal metastasis from thyroid cancer should be multi-disciplinary. There is an absence; it seems, of a definitive protocol for treatment. Research shows increased survival with 131I avidity and complete bone metastasis resection. Early detection and treatment therefore are crucial. Studies suggest in those patients below the age of 45 years that treatment should be aggressive, and aim for cure. In those patients in whom curative treatment is not an option, palliative treatments are available.

Lung metastases in patients with differentiated thyroid carcinoma and evaluation of response to radioiodine therapy

INTRODUCTION

The most common site of metastases in differentiated thyroid carcinomas is the lungs. In our study, we aimed to determine the ratios of lung metastases in patients with differentiated thyroid carcinoma and response to radioiodine therapy.

MATERIAL AND METHODS

A total of 542 patients with differentiated thyroid carcinoma who were admitted to our clinic were included in the study. High doses of (131)I were administered to the patients with lung metastases. Response to therapy were evaluated with (131)I scans and stimulated serum Tg levels were examined at least 6 months after therapy.

RESULTS

Lung metastases were detected in 17 (3.1%) of 542 patients with differentiated thyroid carcinoma. Of these patients to whom high doses of (131)I therapy were administered, complete response to therapy was obtained in 5 (29.4%), partial response was obtained in 3 (17.6%) and no response could be obtained in 9 (53%) patients.

CONCLUSION

Although lung metastases from differentiated thyroid carcinomas are rare, those are more common in advanced ages and in males. High doses of (131)I therapy may be partially beneficial in these patients. Thus repetition of therapy is frequently required.

2012 European thyroid association guidelines for metastatic medullary thyroid cancer

Distant metastases are the main cause of death in patients with medullary thyroid cancer (MTC). These 21 recommendations focus on MTC patients with distant metastases and a detailed follow-up protocol of patients with biochemical or imaging evidence of disease, selection criteria for treatment, and treatment modalities, including local and systemic treatments based on the results of recent trials. Asymptomatic patients with low tumor burden and stable disease may benefit from local treatment modalities and can be followed up at regular intervals of time. Imaging is usually performed every 6-12 months, or at longer intervals of time depending on the doubling times of serum calcitonin and carcinoembryonic antigen levels. Patients with symptoms, large tumor burden and progression on imaging should receive systemic treatment. Indeed, major progress has recently been achieved with novel targeted therapies using kinase inhibitors directed against RET and VEGFR, but further research is needed to improve the outcome of these patients.

Multidisciplinary treatment and survival of patients with vertebral metastases from thyroid carcinoma

BACKGROUND

Distant metastases from differentiated thyroid carcinoma occur in up to 20% of cases and represent the most frequent cause of thyroid cancer-related death. Metastatic disease to the spine has the potential to cause severe morbidity, including pain, neurological deficit, and paraplegia.

SUMMARY

We present a case series of eight consecutive patients with symptomatic spinal metastases due to thyroid carcinoma treated by our multidisciplinary team consisting of spinal surgeons, oncologists, and radiologists, with management of each case determined by our surgical algorithm. Four patients underwent surgical decompression and stabilization for spinal metastases causing instability, spinal cord compression, neurological deficit, or intractable pain. Three patients underwent vertebroplasty for focal mechanical pain due to osteolytic metastases in the absence of significant spinal cord compression or spinal instability; one of these patients required subsequent surgical decompression for spinal cord compression. One patient was nonoperatively treated. All patients underwent total thyroidectomy for the primary cancer and adjuvant radioiodine-131 treatment. The only patient with poorly differentiated thyroid cancer, which was refractory to radioiodine-131 died at 6 months after vertebroplasty procedures for symptomatic spinal metastases. One patient with medullary thyroid carcinoma died at 18 months after vertebroplasty. All remaining six patients who had well-differentiated papillary or follicular thyroid carcinoma were alive at an average of 50 months (range: 17-96 months) after diagnosis and treatment of symptomatic spinal metastases and were ambulant, independent, and able to perform activities of daily living and had no significant pain or neurologic symptoms.

CONCLUSION

The potential for long-term survival of several years following development of spinal metastases should be considered during the counseling and decision-making process for patients with thyroid cancer.

Clinical implications of bilateral lateral cervical lymph node metastasis in papillary thyroid cancer: a risk factor for lung metastasis

BACKGROUND

Distant metastasis to the lung in papillary thyroid cancer (PTC) is rarely detected, but it is known to be an important prognostic factor associated with survival. We investigated risk factors for lung metastasis in PTC.

MATERIALS AND METHODS

We performed a retrospective review of patients with PTC (n=977) who were treated from January 2006 to August 2009. Enrolled patients received radioablation therapy followed by a radioiodine whole body scan. Lung metastasis was screened out with whole body scan or positron emission tomography/computed tomography (PET/CT) and confirmed with chest CT. Age, gender, extrathyroidal extension, central lymph node metastasis, lateral lymph node metastasis, and bilateral lateral cervical lymph node metastasis (BLNM) were investigated to analyze the relationship with lung metastasis.

RESULTS

In total, 949 patients were enrolled. The median age was 49 years (±13 years) with 829 women. Lung metastasis was found in 20 patients (2.1%). Patients were divided into three groups by tumor size (≤1 cm, 1-2 cm, >2 cm); the groups comprised 47.3%, 28.5%, and 24.1% of the patients, respectively. BLNM was identified in 4.4% (n=43). In a univariate analysis, male gender, old age, large tumor, extrathyroidal extension, lymph node metastasis, lateral lymph node metastasis, and BLNM were significantly related to lung metastasis (P<0.05). In a multivariate analysis, BLNM appeared to be the only significant risk factor for lung metastasis (P=0.026; odds ratio=10.219).

CONCLUSIONS

BLNM may be a risk factor for lung metastasis. This indicates that careful examinations, including chest CT and positron emission tomography (PET), are recommended during the follow-up period when BLNM is suspected.

Selective arterial embolisation for bone tumours: experience of 454 cases

PURPOSE

The authors present the experience of a single institution with selective arterial embolisation for primary and metastatic bone tumours.

MATERIALS AND METHODS

A total of 365 patients were treated with 454 embolisation procedures from December 2002 to April 2010. Embolisation was the primary treatment for benign bone tumours, adjuvant treatment to surgery for benign and malignant bone tumours and palliative treatment for bone sarcomas and metastases. Indications for repeat embolisation included pain or imaging evidence of progressive disease: 105 patients had repeat embolisation at the same location at an interval of 1-3 months; 260 patients had one embolisation, 78 had two and 29 had three or more. In all patients, N-2-butyl cyanoacrylate (NBCA) in 33% lipiodol was the embolic agent used.

RESULTS

A total of 419 of the 454 embolisations (93%) were technically successful. In 35 cases, embolisation was not feasible because of poor lesion vascularisation (21 patients with bone metastases and two with aneurysmal bone cysts), origin of the Adamkiewicz artery in the embolisation field (four patients with bone metastases and one with aneurysmal bone cyst), atheromatosis and arteriosclerosis (five patients with bone metastases) and anatomical and technical problems such as small-calibre vessels, many branches and acute vessel angles (two patients with bone metastases). A clinical response was achieved in 406 of the 419 procedures (97%), and no response in 13 procedures in patients with pelvis and sacrum tumours. Complications included postembolisation syndrome in 81 patients (22%), transient paraesthesias in 41 (11%), skin breakdown and subcutaneous necrosis at the shoulder and pelvis in five (1.4%) and paresis of the sciatic nerve in one (0.3%).

CONCLUSIONS

We recommend embolisation as primary or palliative treatment or an adjunct to surgery for tumours of variable histology. Strict adherence to the principles of transcatheter embolisation is important. Arteries feeding the tumour and collaterals must be evaluated carefully and catheterised superselectively to protect the normal tissues. NBCA is considered the most appropriate embolic agent for small-vessel occlusion without major complications.

The effectiveness of radioactive iodine for treatment of low-risk thyroid cancer: a systematic analysis of the peer-reviewed literature from 1966 to April 2008

BACKGROUND

Radioactive iodine (RAI) remnant ablation has been used to eliminate normal thyroid tissue and may also facilitate monitoring for persistent or recurrent thyroid carcinoma. The use of RAI for low-risk patients who we define as those under age 45 with stage I disease or over age 45 with stage I or II disease based on American Joint Committee on Cancer (AJCC) 6th edition, or low risk under the metastases, age, completeness of resection, invasion, size (MACIS) staging system (value <6) is controversial. In this extensive literature review, we sought to analyze the evidence for use of RAI treatment to improve mortality and survival and to reduce recurrence in patients of various stages and disease risk, particularly for those patients who are at low risk for recurrence and death from thyroid cancer.

METHODS

A MEDLINE search was conducted for studies published between January 1966 and April 2008 that compared the effectiveness of administering versus not administering RAI for treatment of differentiated thyroid cancer (DTC). Studies were grouped A through D based on their methodological rigor (best to worst). An analysis, focused on group A studies, was performed to determine whether treatment with RAI for DTC results in decreased recurrences and improved survival rates.

RESULTS

The majority of studies did not find a statistically significant improvement in mortality or disease-specific survival in those low-risk patients treated with RAI, whereas improved survival was confirmed for high-risk (AJCC stages III and IV) patients. Evidence for RAI decreasing recurrence was mixed with half of the studies showing a significant relationship and half showing no relationship.

CONCLUSIONS

We propose a management guideline based on a patient's risk-very low, low, moderate, and high-for clinicians to use when delineating those patients who should undergo RAI treatment for initial postoperative management of DTC. A majority of very low-risk and low-risk patients, as well as select cases of patients with moderate risk do not demonstrate survival or disease-free survival benefit from postoperative RAI treatment, and therefore we recommend against postoperative RAI in these cases.

Standard and emerging therapies for metastatic differentiated thyroid cancer

Differentiated thyroid cancer accounts for >90% of cases of thyroid cancer, with most patients having an excellent prognosis. Distant metastases occur in 10%-15% of patients, decreasing the overall 10-year survival rate in this group to 40%. Radioactive iodine has been the mainstay of treatment for distant metastases, with good results when lesions retain the ability to take up iodine. For patients with metastatic disease resistant to radioactive iodine, treatment options are few and survival is poor. Chemotherapy and external beam radiotherapy have been used in these patients, but with disappointing results. In recent years, our understanding of the molecular pathways involved in thyroid cancer has increased and a number of molecular targets have been identified. These targets include the proto-oncogenes BRAF and RET, known to be common mutations in thyroid cancer; vascular endothelial growth factor receptor and platelet-derived growth factor receptor, associated with angiogenesis; and the sodium-iodide symporter, with the aim of restoring its expression and hence radioactive iodine uptake. There are now multiple trials of tyrosine kinase inhibitors, angiogenesis inhibitors, and other novel agents available to patients with metastatic thyroid cancer. This review discusses both traditional and novel treatments for metastatic differentiated thyroid cancer with a particular focus on emerging treatments for patients with radioactive iodine-refractory disease.

Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the publication of the American Thyroid Association's guidelines for the management of these disorders was published in 2006, a large amount of new information has become available, prompting a revision of the guidelines.

METHODS

Relevant articles through December 2008 were reviewed by the task force and categorized by topic and level of evidence according to a modified schema used by the United States Preventative Services Task Force.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to optimal surgical management, radioiodine remnant ablation, and suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using ultrasound and serum thyroglobulin as well as those related to management of recurrent and metastatic disease.

CONCLUSIONS

We created evidence-based recommendations in response to our appointment as an independent task force by the American Thyroid Association to assist in the clinical management of patients with thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

13-cis-retinoic acid re-differentiation therapy and recombinant human thyrotropin-aided radioiodine treatment of non-Functional metastatic thyroid cancer: a single-center, 53-patient phase 2 study

In 30-50% of patients with metastatic non-medullary thyroid cancer the metastases are not radioiodine-avid and so there is no effective treatment. Retinoids have demonstrated inhibition of thyroid tumor growth and induction of radioiodine uptake. The aim of our study was to assess benefits of the retinoic acid (RA) treatment to re-differentiate non-functional NMTC metastases.

PATIENTS AND METHODS

In this prospective study, 53 patients with radioiodine non avid metastatic disease (45) or hyperthyroglobulinemia (8) were treated with 13-cis-retinoic acid (13-CRA) [1.0 mg/kg/day over 1st week and then 1.5 mg/kg] for six weeks prior to I-131 treatment performed under rhTSH stimulation. The re-differentiating effect of RA was evaluated by serum thyroglobulin (Tg) monitoring before and after cessation of RA treatment and by qualitative analysis of iodine uptake on the post-therapeutic whole body scan (rxWBS).

RESULTS

13-CRA induced radioiodine uptake in 9 (17%) of patients. In the univariate analysis neither the patient's gender, age, tumor histopathology, uptake in thyroid bed nor time since thyroid cancer diagnosis was associated with results of rxWBS.41 (77%) patients were evaluable for Tg response before and after to 13-CRA treatment. There was a statistically significant increase in median Tg level (60 v. 90 ng/ml, p < 0.05). There was no difference in Tg increase between scintigraphic responders and non-responders.13-CRA and RIT was repeated at least once in 8 of 9 scintigraphic responders. None of them showed tumor regression by radiological imaging within 12 months after the first treatment, 4/9 (44%) of them had disease progression.13-CRA treatment was well-tolerated. All but one patient complained of at least one side effect the most prevalent being lip dryness (98%). All side effects were transient and resolved within 2 weeks after 13-CRA cessation.

CONCLUSION

Our results show that in patients with non-functional metastases from NMTC, 13-CRA is able to exert some re-differentiation effect by induction of radioiodine uptake in <20% of patients and increase of Tg serum level in about 30% of them. Nevertheless, this does not transfer into clinical benefit as it neither induces measurable tumor response nor prevents disease progression.

Chest wall resection and reconstruction using titanium micromesh covered with Marlex mesh for metastatic follicular thyroid carcinoma: a case report

Introduction

The distant metastases from differentiated thyroid carcinomas are often untreatable. In particular, bone metastasis is significantly related to poor prognosis since radioactive iodine therapy is generally less effective. Therefore, surgical resection is considered one of the treatments for patients with bone metastases. We report chest wall resection and reconstruction using titanium micromesh covered with polypropylene mesh (Marlex mesh) for metastatic rib bones as a result of follicular thyroid carcinoma.

Case presentation

A 51-year-old man was referred to our institution with a painful chest wall tumor. He presented with a 15 × 10 cm bony swelling on the left chest wall and multiple small lung nodules from follicular thyroid carcinoma. Completion total thyroidectomy, chest wall resection and reconstruction using titanium micromesh covered with Marlex mesh were performed. There were no critical complications associated with surgical treatments and tumor pain disappeared during the postoperative period. Then, he received radioactive iodine therapy and the uptake of radioactive iodine was well observed in bilateral lung fields.

Conclusion

Reconstruction using titanium micromesh covered with Marlex mesh is possible for repairing the wide chest wall resection required for thyroid carcinoma metastasis. This technique would help to enhance treatment efficacy in the combination therapy of radioactive iodine and surgery in patients with large thyroid carcinoma metastasis in the chest wall.

Medical management of persistent or recurrent differentiated thyroid carcinoma

This article presents an overview of medical management of persistent or recurrent differentiated thyroid cancer, in particular focusing on monitoring strategy and treatment plans. Most patients with differentiated thyroid carcinoma can be successfully rendered to be free of disease with initial treatments, and those with persistent or recurrent disease can still expect long-term survival when they are monitored properly and treated accordingly. Along with serum thyroglobulin, neck ultrasonography, and radioactive iodine whole-body scans, the use of cross-sectional imaging studies and (18F) fluoro-2-deoxy-D-glucose-positron emission tomography have facilitated the effort in localizing lesions and traditional treatments can be implemented effectively. For disease resistant to conventional therapies, there are new treatment modalities emerging and being tested, including several agents targeting specific signaling pathways, each of which may offer the potential remedy.

Radio-iodine therapy in differentiated thyroid cancer: indications and procedures

Post-surgical ablative iodine-131 therapy is recommended for all differentiated thyroid cancer primary tumors>1 cm in diameter. Regarding smaller primary tumors, 131I ablation may be helpful in special cases: tumor close to the thyroid capsule, previous percutaneous radiation to the neck, familial occurrence of thyroid cancer, tumor diameter 5-10 mm, and unfavorable histological variants. In this context, the patient's preferences for safety should be considered. In most centers, standard fixed activities of 1-3 GBq are used for 131I ablation. Preparation for the procedure with such activities requires a low-iodine diet for 2-3 weeks and stimulation of thyroid stimulating hormone (TSH) by withholding of thyroid hormone for 3 weeks following thyroidectomy or by use of recombinant human TSH. The advantages of recombinant TSH are avoidance of hypothyroid morbidity and consequently a better quality of life, as well as a lower radiation dose to extra-thyroidal compartments. To treat metastastic differentiated thyroid cancer, higher activities of radio-iodine (in the range 4-11 GBq) are necessary; if possible, individual dosimetry is recommended. The standard approach to preparation for 131I therapy in patients with metastases is endogenous hypothyroidism after thyroid hormone withdrawal.

External beam radiation therapy for thyroid cancer

This article discusses the role of external beam radiotherapy (XRT) in the management of well-differentiated thyroid cancer (WDTC), medullary thyroid cancer, and anaplastic thyroid cancer. Although there are no randomized controlled studies on the use of XRT in thyroid cancer, evidence supports its use to treat gross disease after surgery or unresectable cancer and its use as an adjuvant after resection of a known high-risk disease in WDTC, and, to a lesser extent, in medullary thyroid cancer. The use of XRT for the palliation of symptomatic disease and recent advances in the technology of radiation delivery also will be discussed.

Thyroid and bone

This article provides a summary of the numerous interactions between the thyroid gland and the skeleton, in the normal state, in disorders of thyroid function and as a result of thyroid malignancy. It recaps the current understanding of bone growth and development in the endochondral growth plate and the normal mechanisms of mature bone remodeling. The actions of thyroid hormones on these processes are described, and the clinical impact of thyroid disorders and their treatments on the bone are summarized. Finally, our current understanding of the physiology of bone metastases from thyroid cancer is covered.

Uso do TSH humano recombinante no câncer diferenciado de tireóide

O seguimento imediato após tireoidectomia total (TT), em pacientes com câncer diferenciado de tireóide (CDT), tradicionalmente é feito com a ablação de remanescentes tireoidianos (RT) com 131I, na vigência de hipotireoidismo. O seguimento tardio do CDT inclui o uso de doses supressivas de T4, dosagem seriada da tireoglobulina (Tg), pesquisa de corpo inteiro (PCI) com 131I e ultra-sonografia (US) cervical. Nos últimos anos, tem-se mostrado que a ablação de RT com a ajuda do TSH recombinante humano (rhTSH) tem a mesma eficácia que a ablação de RT observada com a elevação endógena do TSH, mas sem os sintomas e piora de qualidade de vida descritos no hipotireoidismo. A dosagem da Tg estimulada com TSH endógeno ou exógeno, 9 a 12 meses após o tratamento inicial do CDT, associado à US cervical, pode identificar pacientes de baixo risco potencialmente curados de sua doença e nos quais a supressão do TSH não necessita ser tão intensa, evitando as complicações cardíacas e ósseas da tireotoxicose exógena prolongada. Finalmente, apesar de não existirem estudos randomizados que avaliem o papel do rhTSH no tratamento do CDT metastático, os resultados do tratamento combinado do rhTSH e 131I mostram um benefício clínico na maioria dos pacientes tratados.

Nódulos de tireóide e câncer diferenciado de tireóide: consenso brasileiro

Os nódulos tireoidianos constituem a principal manifestação clínica de uma série de doenças da tireóide com uma prevalência de aproximadamente 10% na população adulta. O maior desafio é excluir o câncer da tireóide, que ocorre em 5 a 10% dos casos. Os carcinomas diferenciados respondem por 90% dos casos de todas as neoplasias malignas da tireóide. A maioria dos pacientes com carcinoma diferenciado apresenta, geralmente, um bom prognóstico quando tratada adequadamente, com índices de mortalidade similares à população geral. No entanto, alguns indivíduos apresentam doença agressiva, desafiando o conhecimento atual e ilustrando a complexidade do manejo dessa neoplasia. No presente trabalho, reunimos 8 membros do Departamento de Tireóide da Sociedade Brasileira de Endocrinologia & Metabologia, para elaborarmos, por consenso, as diretrizes brasileiras no manejo dos nódulos tireoidianos e do câncer diferenciado da tireóide. Os membros participantes representam diferentes Centros Universitários do Brasil, refletindo diferentes abordagens diagnósticas e terapêuticas. Inicialmente, cada participante ficou responsável pela redação de determinado tema a ser enviado ao Coordenador, que, após revisão editorial e elaboração da primeira versão do manuscrito, enviou ao grupo para sugestões e aperfeiçoamentos. Quando concluído, o manuscrito foi novamente enviado e revisado por todos. A elaboração dessas diretrizes foi baseada na experiência dos participantes e revisão pertinente da literatura.

Clinical management and outcome of papillary and follicular (differentiated) thyroid cancer presenting with distant metastasis at diagnosis

BACKGROUND

Differentiated thyroid cancer has a good prognosis and only rarely presents with distant metastasis at diagnosis. The clinical outcome of this presentation was assessed with respect to survival and factors that may determine prognosis.

METHODS

A retrospective review was undertaken of patients with stage M1 differentiated thyroid cancer at presentation (n = 49), referred from 1980-2000 at a single institution.

RESULTS

The median age was 68 (range, 17-90), with 69% females. The initial site(s) of metastasis were lung only, 45%, bone only, 39%, other single site, 4%, and multiple sites, 12%.

HISTOLOGY

papillary, 51%, follicular, 49%. Initial treatment(s) included: thyroidectomy, 82%, radioactive iodine (RAI), 88%, excision of metastasis, 29%, radiotherapy, 47%, and chemotherapy, 6%. With a median follow-up time of 3.5 years, 25 patients are alive (51%) and 24 died (49%), with 3-year and 5-year actuarial survivals of 69% and 50%, respectively. Only a minority of patients (4/25, 16%) had no clinical evidence of disease at last follow-up. Most deaths (17/24, 71%) were due to progressive cancer. Prognosis was associated with age, site of metastasis, histology, and iodine avidity of the metastasis. Patients aged </=45 (n = 8) had a 3-year survival of 100%, versus 62% for those age > 45 years (P = .001). The 3-year survival for lung only versus bone only metastasis was 77% versus 56% (P = .02); for papillary versus follicular carcinoma, 75% versus 62% (P = .006); for iodine-avid disease (n = 29) versus not avid (n = 14), 82% versus 57% (P = .02), respectively. In multivariate analysis after adjusting for age, only histology and iodine avidity remained significant for survival. The hazard ratio for follicular histology was 3.7 (95% confidence interval [CI], 1.1-12.1, P = .03), and for tumors not avid for iodine, 3.4 (95% CI, 1.2-9.2, P = .02).

CONCLUSIONS

The data support the aggressive management of patients presenting with stage M1 thyroid cancer, with thyroidectomy and RAI. Complete clinical eradication of disease was rarely seen, and 50% of patients survived for more than 5 years. Young patients with papillary tumors and/or iodine-avid disease have an even better prognosis.

Follicular thyroid carcinoma: From diagnosis to treatment

Unusual presentations with bone, lung or soft tissue metastases in initial diagnosis of follicular thyroid carcinoma have been reported occasionally. This implies how difficult it is to diagnosis this type of cancer at the pre-operative or intra-operative stage of treatment. Fine needle aspiration cytology has been shown to be an ineffective method for diagnosing vascular or capsule invasion of follicular thyroid cancer. Multiple frozen sections, usually 5 to 12 depending on the size of the tumor, can achieve a diagnostic accuracy of 98%. Clinical application of various gene expressions in thyroid follicular tumors by needle aspiration using in situ hybridization requires further investigation. Although radioactive iodide (131I) has been used as the standard treatment for follicular thyroid carcinoma with distant metastases, the effectiveness of 131I treatment for follicular thyroid carcinoma depends on the differentiation of cancer cells. The possibility of 131I for thyroid remnant ablation replacing a secondary operation for follicular thyroid carcinoma has been debated. Recent studies applied more expressions of sodium iodide symporters to attain the effect of 131I treatment and slow the proliferation of thyroid cancer cell which, in turn, slows the progression of follicular carcinoma. Consensus for the surgical procedures for the specific prognostic risks for follicular thyroid carcinoma is needed. Dedifferentiated, anti-angiogenic, or gene therapies for follicular thyroid cancer with distant metastases or anaplastic transformation comprise the principal directions in future research for this cancer.

Effects of histone acetylation on sodium iodide symporter promoter and expression of thyroid-specific transcription factors

Inhibitors of histone deacetylases (HDACs) activate the sodium iodide symporter (NIS) expression in thyroid tumor cells. In this study, mechanisms accounting for these effects were investigated. Various human thyroid tumor cell lines (ARO, BCPAP, FRO, TPC-1) were treated with the HDAC inhibitors Na butyrate (NaB) and tricostatin A (TSA), and the effects on the expression of NIS and several thyroid-specific transcription factors together with the activity of NIS promoter were evaluated. TSA and NaB increased NIS mRNA levels in all cell lines. Among thyroid-specific transcription factors, only expression of PAX8 in ARO cells was increased. Down-regulation of thyroid-specific transcription factor-1 expression was observed in BCPAP and TPC-1 cell lines. Thyroid-specific transcription factor-2 mRNA was reduced in FRO, BCPAP, and TPC-1 cells. Histone acetylation had no significant effects on HEX expression. Altogether, these data indicate that the increase of NIS expression is not mediated by modification of expression of thyroid-specific transcription factors. Accordingly, in transfection experiments performed in the HeLa cell line (which does not express thyroid-specific transcription factors), treatment with TSA and NaB increased NIS promoter activity. Stimulation of NIS promoter activity was also obtained by overexpressing histone acetylating proteins pCAF and p300 in HeLa cells. Conversely, overexpression of the HDAC 1 enzyme inhibited basal activity of the NIS promoter. Effects of TSA and NaB on NIS expression were also evaluated in nonthyroid cell lines MCF-7, Hep-G2, and SAOS-2. In all cell lines TSA and NaB greatly increased NIS mRNA levels. We concluded that control of NIS expression by inhibition of HDAC appears not to be mediated by cell-specific mechanisms, suggesting it as a potential strategy to induce radioiodine sensitivity in different human tumors.

Antivascular Therapy of Human Follicular Thyroid Cancer Experimental Bone Metastasis by Blockade of Epidermal Growth Factor Receptor and Vascular Growth Factor Receptor Phosphorylation

Patients suffering from bone metastases of follicular thyroid carcinoma (FTC) have a poor prognosis because of the lack of effective treatment strategies. The overexpression of epidermal growth factor receptor (EGFR) associated with increased vascularity has been implicated in the pathogenesis of FTC and subsequent bone metastases. We hypothesized that inhibiting the phosphorylation of the EGFR and vascular endothelial growth factor receptor (VEGFR) by AEE788, a dual tyrosine kinase inhibitor of EGFR and VEGFR, in combination with paclitaxel would inhibit experimental FTC bone lesions and preserve bone structure. We tested this hypothesis using the human WRO FTC cell line. In culture, AEE788 inhibited the EGF-mediated phosphorylation of EGFR, VEGFR2, mitogen-activated protein kinase, and Akt in culture. AEE788, alone and in combination with paclitaxel, inhibited cell growth and induced apoptosis. When WRO cells were injected into the tibia of nude mice, tumor and endothelial cells within the lesions expressed phosphorylated EGFR, VEGFR, Akt, and mitogen-activated protein kinase that were inhibited by the oral administration of AEE788. Therapy consisting of orally given AEE788 and i.p. injected paclitaxel induced a high level of apoptosis in tumor-associated endothelial cells and tumor cells with the inhibition of tumor growth in the bone and the preservation of bone structure. Collectively, these data show that blocking the phosphorylation of EGFR and VEGFR with AEE788 combined with paclitaxel can significantly inhibit experimental human FTC in the bone of nude mice.

Preoperative Scintigraphic Visualization of an Orbital Metastasis Before Identification of Carcinoma in a Nonfunctioning Thyroid Nodule

Preoperative accumulation of Tc-99m pertechnetate and radioiodine in metastases of well-differentiated thyroid carcinoma is uncommon. The authors report the case of a 51-year-old woman with follicular thyroid carcinoma revealed by a right orbital metastasis. I-131 scintigraphy performed before thyroidectomy showed intense uptake in an orbital metastasis despite the presence of an intact thyroid gland.

Appointments at a thyroid outpatient clinic and the lunar cycle

INTRODUCTION

Several variables of health-related human behaviour have been analysed with regard to a possible association with lunar phases. The aim of this study was to evaluate a possible relation between the lunar cycle and the number of requests for appointments at an outpatient clinic. This variable has not been studied hitherto.

METHODS

We analysed a total number of 11,413 requests for appointments at our thyroid outpatient clinic during one year. Access to this clinic is not restricted, and all patients with known or suspected thyroid disease living in the area of Vienna may ask for an appointment. During the study period, 8,852 patients requested a follow-up appointment, and 2561 patients asked for a new appointment. We analysed a possible cyclic pattern in these requests using a nonlinear regression model based on both groups of patients.

RESULTS

A cosinus curve with a period of 29.531 days (the mean length of a lunar cycle) was significantly associated with the number of requests for both follow-up appointments (p = 0.007) and new appointments (p = 0.001). Requests for follow-up appointments had their highest peaks three days after the full moon, whereas requests for new appointments were most frequent five days afterwards.

CONCLUSION

Our findings suggest that lunar phases may affect patients' requests for appointments at a thyroid outpatient clinic. To the best of our knowledge, this is the first study reporting a possible association between health-related behaviour and lunar phases using requests for appointments as a relevant variable. There is a need for more research into the mechanism underpinning this behaviour.