Bone metastases from thyroid carcinoma: a histopathologic study with clinical correlates

Unexpected Widespread Bone Metastases from a BRAF K601N Mutated Follicular Thyroid Carcinoma within a Previously Resected Multinodular Goiter

Follicular thyroid carcinoma (FTC) represents the second most common malignant thyroid neoplasm after papillary carcinoma (PTC). FTC is characterized by the tendency to metastasize to distant sites such as bone and lung. In the last 20 years, the understanding of the molecular pathology of thyroid tumors has greatly improved. Uncommon BRAF non-V600E mutations have been identified and are generally believed to associate with follicular patterned tumors of low malignant potential, particularly non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTPs) (i.e., non-invasive encapsulated follicular variant PTC). We here report for the first time widespread bone metastases from a BRAF K601N mutated follicular tumor.

The presenting dental status of solid tumours with bone metastases requiring bone-targeting agents - part 4: miscellaneous cancers

This article discusses relevant information for the dental sector regarding metastatic cancers beyond breast and prostate cancer. Typically, tumour sites such as lung, renal, colorectal, gastrointestinal, thyroid, hepatic and pancreatic cancers are increasingly being referred for bone-targeting agents upon evidence of bone metastases.The current article explores the presenting dental status of these tumour groups on the background of survival outcomes. In addition, the article provides insight towards the complexity in achieving 'dental fitness' and whether 'dental stability' could be an alternative to consider via palliative dentistry in certain cases.

Incidence and Predictors of Synchronous Bone Metastasis in Newly Diagnosed Differentiated Thyroid Cancer: A Real-World Population-Based Study

Background

Clinical and sociodemographic characteristics of differentiated thyroid cancer (DTC) patients with synchronous bone metastasis (SBM) remain unclear. This real-world study aimed to elucidate the incidence and prognosis of DTC patients with SBM using population-based data.

Methods

Data of patients with newly diagnosed DTC from 2010 to 2016 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariable logistic regression analysis was utilized to identify predictors of developing SBM in patients with DTC and was further evaluated by receiver operator characteristics (ROC) analysis. Multivariable Cox regression was applied to identify prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS).

Results

A total of 67,176 patients with DTC were screened from the database, with 0.36% (244/67,176) developed SBM. The age-adjusted incidence of SBM in patients with DTC was relatively stable during the study period with an average annual percentage change (AAPC) of 2.52. Multivariable logistic regression analysis recognized seven factors (older age, male gender, black race, other races, follicular histology, the American Joint Committee on Cancer (AJCC) T2, T3, T4 staging, and N1 staging) as predictors of developing SBM among the entire cohort, with the value of area under the curve (AUC) of 0.931 (95% CI: 0.915–0.947). The median survival time of DTC patients with SBM was 22 months (interquartile range, 7–47 months). The multivariable Cox regression analysis indicated multiple metastatic sites, surgical procedures, and chemotherapy as predictors for the survival of patients.

Conclusions

Predictors and prognostic factors of SBM in patients with DTC were identified in this study. Patients with risk factors should be given more attention in clinical practice.

Metformin Reduces Thyroid Cancer Tumor Growth in the Metastatic Niche of Bone by Inhibiting Osteoblastic RANKL Productions

Background: Metformin has antitumoral actions in human cancers, including the thyroid, while its effects on metastatic lesions are unclear. Patients with bone metastasis (BM) from thyroid cancers have poor survival. Because metformin inhibits the activation of osteoclasts, which has essential roles in BM, the aim of this study was to investigate the therapeutic effects of metformin on thyroid cancer BM and osteoclast activation in the bone microenvironment. Methods: The anaplastic thyroid cancer (ATC) cell lines FRO and SW1736 were used to test the antitumoral effect of metformin in vitro and in vivo. A murine model of BM was established by intratibial injection of cancer cells. To mimic the BM microenvironment, osteoblasts were treated with conditioned media from the FRO (FRO-CM) and SW1736 (SW1736-CM) cells. Thyroid cancer patients with or without BM were recruited, and the serum receptor activator of nuclear factor kappa-B ligand (RANKL) levels was measured. Results: Metformin treatment significantly reduced the viabilities of the FRO and SW1736 cells in vitro and the tumor growth of SW1736 in vivo. In the murine model of BM, metformin delayed tumor growth in the bone and decreased the numbers of tartrate-resistant acid phosphatase-positive osteoclasts on the bone surface with reduced RANKL in the bone marrow. Furthermore, FRO- or SW1736-CM significantly increased the osteoblastic RANKL productions and activated osteoclast differentiation in whole marrow cultures, which were blocked by metformin treatment. Among 67 thyroid cancer patients, the serum RANKL levels were significantly increased in BM patients compared with patients with lung-only metastasis or no distant metastasis. In addition, the interleukin-6 superfamily in the FRO- or SW1736-CM stimulated STAT3 phosphorylation, which was inhibited by gp130 blocking. Metformin treatment decreased the FRO- or SW1736-CM-induced STAT3 phosphorylation by AMPK phosphorylation. Metformin also inhibited the FRO- or SW1736-CM-induced osteoclastic differentiation of bone marrow-derived monocyte/macrophage by RANK/c-Fos/NFATC1 signaling. Conclusions: In the microenvironment of BM, metformin effectively reduced ATC tumor growth by inhibiting cancer cell viability, blocking cancer cell-induced osteoblastic RANKL production, which further activated osteoclastogenesis, and directly reduced osteoclast differentiation. These multifactorial actions of metformin suggest that it has potential therapeutic effects in thyroid cancer BM.

2021 American Thyroid Association Guidelines for Management of Patients with Anaplastic Thyroid Cancer

Background: Anaplastic thyroid cancer (ATC) is a rare but highly lethal form of thyroid cancer. Since the guidelines for the management of ATC by the American Thyroid Association were first published in 2012, significant clinical and scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, and researchers on published evidence relating to the diagnosis and management of ATC. Methods: The specific clinical questions and topics addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of the Task Force members (authors of the guideline). Relevant literature was reviewed, including serial PubMed searches supplemented with additional articles. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations. Results: The guidelines include the diagnosis, initial evaluation, establishment of treatment goals, approaches to locoregional disease (surgery, radiotherapy, targeted/systemic therapy, supportive care during active therapy), approaches to advanced/metastatic disease, palliative care options, surveillance and long-term monitoring, and ethical issues, including end of life. The guidelines include 31 recommendations and 16 good practice statements. Conclusions: We have developed evidence-based recommendations to inform clinical decision-making in the management of ATC. While all care must be individualized, such recommendations provide, in our opinion, optimal care paradigms for patients with ATC.

Thyroid Cancer Bone Metastasis: Survival and Genomic Characteristics of a Large Tertiary Care Cohort

Bone metastasis (BM) in differentiated thyroid cancer (DTC) is the second most common site of metastasis after lung. Bone metastases are associated with worse prognosis in DTC. In this study, we examined risk factors for overall survival in patients with BM and for the first time explore the pattern of genomic alterations in DTC BM.

PATIENTS AND METHODS

A Health Insurance Portability and Accountability Act (HIPAA) compliant, institutional review board-approved retrospective evaluation of the medical record was performed for all patients treated at a single institution for thyroid cancer over a 16-year period. Seventy-four patients met inclusion criteria. Multiple prognostic factors including age, sex, genes, radioactive iodine, and radiation or kinase inhibitor therapies were analyzed. Univariate and multivariate analyses were performed.

RESULTS

Treatment with external beam radiation was found to significantly increase survival (P = 0.03). The 5-year survival rate was 59% and median survival was 92 months. Patients who developed bone metastasis earlier tend to live longer (P = 0.06). The presence of TERT and BRAF mutations did not significantly worsen the prognosis (P = 0.10).

CONCLUSION

Patients with DTC can benefit from early treatment with external beam radiation therapy, especially those who develop bone metastasis within 3 years of primary TC diagnosis. Kinase inhibitor treatment tended to prolong survival but not in a statistically significant manner. Sex, age, and TERT or BRAF genetic mutations did not significantly affect the prognosis.

Outcomes of patients with bone metastases from differentiated thyroid cancer

Objective Bone metastases (BM) from differentiated thyroid cancer (DTC) are associated with poor survival rates. Due to the low frequency of this entity, we performed a multicentric retrospective study that aimed to evaluate the presentation, outcome and causes of death in this population. Subjects and methods We reviewed file records from 10 databases. BM were diagnosed by: i) biopsy and/or ii) radioiodine (RAI) bone uptake + elevated thyroglobulin (Tg) levels and/or c) bone uptake of 18-FDG in the PET-CT scan + elevated Tg levels. Results Fifty-two patients with DTC were included (44% male, mean age 54 years); 58% had papillary histology. BM were synchronous with DTC diagnosis in 46% of the participating cases. BM were symptomatic in 65% of the cases. Multiple BM were present in 65% of patients, while simultaneous metastatic disease in additional sites was found in 69%. Ninety-eight percent of patients received treatment for the BM, which included RAI therapy in 42 patients; 30 of them received cumulative RAI doses that were larger than 600 mCi 131I. The mean follow-up after a BM diagnosis was 34 months. The 2- and 5-year survival rates after diagnosis of the first BM were 64% and 38%, respectively. The status on the last evaluation was DTC-related death in 52% of the patients; 26% of them died from direct complications of BM or their treatments. Conclusion BM are usually radioiodine-refractory and are associated with a short overall survival, although most of the patients died of causes not directly related to the BM.

Real-life management and outcome of thyroid carcinoma-related bone metastases: results from a nationwide multicenter experience

PURPOSE AND PATIENTS

The M.O.S.CA.TI. (Metastases of the Skeleton from CArcinoma of the ThyroId) is a multicenter, retrospective study investigating the real-life outcome and management of bone metastases (BM) in 143 patients (63 M, 80 F; median age 64 years, range 11-87) with differentiated thyroid carcinoma (DTC).

RESULTS

Radio-active iodine (RAI) treatment was performed in 131 patients (91.6%), surgical approach and/or external radiotherapy in 68 patients (47.6%), and anti-resorptive bone-active drugs in 32 patients (22.4%; in 31 zoledronate and in one denosumab). At the start of treatment, 24 patients (75.0%) receiving anti-resorptive bone-active drugs had at least one clinical skeletal-related event (SRE) (p < 0.001). One or more clinical SREs (pathological fractures and/or malignant hypercalcemia and/or spinal cord compression) developed in 53 patients (37.1%). Development of SREs was significantly associated with metachronous BM (hazard ratio (HR) 2.04; p = 0.04), localization of BM to cervical spine (HR 3.89; p = 0.01), and lack of avid RAI uptake (HR 2.66; p = 0.02). Thirty-nine patients (27.3%) died in correlation with development of SREs (HR 6.97; p = 0.006) and localization of BM to the hip (HR 3.86; p = 0.02). Moreover, overall mortality was significantly decreased by RAI therapy (HR 0.10; p = 0.02), whereas no significant effects were induced by bone-active drugs (p = 0.36), external radiotherapy (p = 0.54), and surgery (p = 0.43) of BM.

CONCLUSIONS

SREs are very frequent in BM from DTC and they impact patient survival. In the real life, the use of bone-active drugs is currently limited to zoledronate in patients with pre-existing SREs. In this clinical setting, RAI therapy, but not zoledronate, decreased mortality.

Bone Metastases in Follicular Carcinoma of Thyroid

Though the association between follicular carcinoma and bone metastasis is well established, the site-wise distribution is not known. One hundred seventy-three patients of follicular carcinoma presenting between 2003 and 2011 were selected from 1093 patients of follicular lesions presenting at a single institution. Of these, 59 (34%) with bone metastasis were included in the study. Fifty of the 59 patients (84.7%) had metastasis at presentation, while 9 developed bone metastasis during follow-up. Sixty-one percent had solitary metastasis, 15 (25.4%) had multiple bone involvement, while 8 patients (13.6%) had synchronous lung metastasis. Overall, the spine was the commonest site of bone metastases, seen in 20 patients (33.9%), followed by the pelvis, skull, long bones and sternum. Bone metastasis is a known phenomenon in follicular carcinoma. The spine is the commonest site followed by the pelvis.

Skeletal Complications and Mortality in Thyroid Cancer: A Population-Based Study

CONTEXT

Although bone is a common site for tumor metastases, the burden of bone events [bone metastases and skeletal-related events (SREs)] in patients with thyroid cancer is not well known.

OBJECTIVE

To measure the prevalence of bone events and their impact on mortality in patients with thyroid cancer.

PATIENTS, DESIGN, AND SETTING

We identified patients diagnosed with thyroid cancer between 1991 and 2011 from the linked Surveillance Epidemiology and End Results-Medicare dataset. Multivariable logistic regression was used to identify the risk factors for bone metastases and SREs. We used Cox proportional hazards regressions to assess the impact of these events on mortality, after adjusting for patient and tumor characteristics.

RESULTS

Of the 30,063 patients with thyroid cancer, 1173 (3.9%) developed bone metastases and 1661 patients (5.5%) developed an SRE. Compared with papillary thyroid cancer, the likelihood of developing bone metastases or an SRE was higher in follicular thyroid cancer [odds ratio (OR), 2.25; 95% confidence interval (CI), 1.85 to 2.74 and OR, 1.40; 95% CI, 1.15 to 1.68, respectively] and medullary thyroid cancer (OR, 2.16; 95% CI, 1.60 to 2.86 and OR, 1.62; 95% CI, 1.23 to 2.11, respectively). The occurrence of a bone event was associated with greater risk of overall and disease-specific mortality [hazard ratio (HR), 2.14; 95% CI, 1.94 to 2.36 and HR, 1.59; 95% CI, 1.48 to 1.71, respectively]. Bone events were a poor prognostic indicator even when compared with patients with other distant metastases (P < 0.001 and P < 0.001 for overall and disease-specific mortality, respectively).

CONCLUSIONS

Bone events in patients with thyroid cancer are a poor prognostic indicator. Patients with follicular and medullary thyroid cancers are at especially high risk for skeletal complications.

Recurrent spinal metastasis of a sporadic medullary carcinoma of the thyroid after radiation therapy: a case report and review of the literature

Sporadic Medullary Carcinoma of the Thyroid is a relatively uncommon entity and at the time of diagnosis, most already present loco-regional metastasis. Therapy should be aggressive to reduce recurrence and mortality. Follow-up period should continue lifelong and should also include calcium/pentagastrin infusion test, as well as 6-month interval diagnostic imaging.

Clavicle metastasis from carcinoma thyroid- an atypical skeletal event and a management dilemma

Bone metastases is a well described event in the natural history of thyroid cancers and has the potential to severely impact the quality of life by causing pain, fractures and spinal cord compression. Follicular thyroid carcinomas have a greater propensity for distal metastasis than papillary and anaplastic thyroid carcinomas. The most common sites of skeletal metastasis among thyroid cancer patients are femur followed by humerus, pelvis, radius, and scapula. Clavicle metastasis at initial presentation is exceedingly rare. Although many studies have examined the various prognostic factors for patients with bony metastases from thyroid cancers, very few have actually evaluated the effects of surgical management. We present an unusual case of metastatic papillary carcinoma thyroid presenting with clavicle metastasis and review the role of surgical management of bone metastases. Clavicular resection as a part of the management of metastatic papillary carcinoma thyroid has, to the best of our knowledge never been reported before.

Spinal cord compression as initial presentation of metastatic occult follicular thyroid carcinoma

Metastatic tumors are the most common tumors of the spine, accounting for 98% of all spine lesions. But spinal cord compression as the initial presentation of metastatic occult follicular carcinoma without any thyroid enlargement is unusual and relatively rare. This report describes a 35-years-old female patient presenting with paraplegia and urinary incontinence for the last two months. She had no thyroid enlargement; no thyroid related symptoms and her biochemical thyroid profile was normal. Magnetic resonance imaging (MRI) of spine shows a huge mass compressing the spinal cord at D11-D12 involving both the spinal and paraspinal areas. The patient was treated by surgery and radioiodine ablation as the histopathology showed metastatic follicular thyroid carcinoma. This case was reported because of the rarity of the disease. Early diagnosis and initiation of the treatment should promise a good prognosis for a patient with metastatic spinal cord compression.

Iodophilic synchronous phalangeal and choroidal metastasis from follicular thyroid carcinoma: a case report and review

BACKGROUND

Follicular thyroid cancers constitute 15-20% of all thyroid tumors. The usual mode of dissemination is via the hematogenous route. The most common sites of distant metastasis are to the lungs and bones.

OBJECTIVE

A case is presented to demonstrate the unusual presentation of follicular cancer with synchronous digital (distal phalanx of the little finger) and choroidal metastasis that was responsive to radioiodine treatment.

CASE REPORT

A 54-year-old female presented with swelling over the terminal part of the left little finger with thyromegaly. Investigations revealed metastasis from follicular thyroid cancer to the little finger along with pulmonary metastases. She underwent total thyroidectomy with central compartment clearance followed by (131)I therapy. Subsequent follow-up demonstrated complete regression of the digital metastasis and partial regression of the choroidal metastasis which was evaluated after the radioiodine scan that picked up the choroidal metastasis.

CONCLUSION

Follicular thyroid cancers can rarely spread to unusual sites like the digits and choroid. This report highlights the synchronous presentation of digital and choroidal metastasis which responded to (131)I therapy.

A case of concurrent several forms of thyroid cancer

Simultaneous occurrence of papillary and follicular thyroid cancer, known as differentiated thyroid cancer, has been reported with various presentations, but presence of an anaplastic cancer, as an undifferentiated cancer, in addition to differentiated thyroid cancer is rarely reported. We here report a 40-year-old man with papillary thyroid cancer on his right thyroid lobe and metastasized to the right posterior triangle of the neck. Survey on the mass in the right posterior triangle revealed presence of simultaneous papillary, follicular, and anaplastic thyroid cancer. The patient underwent right thyroid lobectomy and he received adjuvant radiotherapy in combination with chemotherapy.

Skull metastasis revealing a papillary thyroid carcinoma

Although thyroid carcinoma is a relatively common form of malignancy, metastatic spread to the skull is rare. Here, we report a case of papillary thyroid carcinoma with frontal and parietal metastasis. A 61-year-old Chinese woman presented with a one year history of a growing mass on the center of the frontal and parietal bone, initially thought to be meningioma. Biopsy of the skull base mass after intracalvarium excision, indicated a tumor of thyroid origin. One month later the patient underwent a total thyroidectomy. Pathological examination confirmed a diagnosis of papillary thyroid carcinoma with frontal and parietal bone metastasis. Based on this experience, the key to successful management of the skull metastasis of thyroid carcinoma is prompt diagnosis and appropriate treatment. Skull metastasis should be considered at the outset of the clinical course of papillary thyroid cancer. To facilitate this, patients should be meticulously investigated by a multidisciplinary team to improve quality of life.

An unusual cause of progressive quadriparesis

Thyroid carcinoma is a rare cause of compressive myelopathy. Quadriparesis as the presenting manifestation of follicular carcinoma of thyroid without any preceding features of malignancy is quite uncommon. We describe a case of a 55-year-old woman who presented with progressive quadriparesis of 2 months duration, on evaluation was found to have a large tumor destroying C1, C2 vertebrae and occupying craniovertebral junction. Histopathological examination of excised tumor was follicular thyroid carcinoma. She was successfully managed with surgical excision, stabilization of spine followed by radiotherapy.

Sites of metastases of anaplastic thyroid carcinoma: autopsy findings in 45 cases from a single institution

BACKGROUND

Despite surgical treatment, chemotherapy, and/or radiotherapy, the vast majority of patients with anaplastic thyroid carcinoma (ATC) have a dismal prognosis. Better knowledge of the frequency of metastases to different sites might help us to perform the appropriate diagnostic tests before treatment and during the course of the disease. The aim of this study was to determine the frequency of metastases from ATC in different sites as found at autopsy.

METHODS

Altogether, 205 patients were treated for ATC at our institute during the years 1972-2008. Autopsy was performed in 45 cases (30 females, 15 males; median age 66 years). The relative frequencies of metastases in different sites were analyzed using descriptive statistics.

RESULTS

Altogether, 41 cases (91%) had metastases at autopsy. The most common sites of metastases were the lungs (78%), intrathoracic lymph nodes (58%), neck lymph nodes (51%), pleura (29%), adrenal glands (24%), liver (20%), brain (18%), heart (18%), and retroperitoneal lymph nodes (18%). Less common sites of distant metastases were the pericardium (13%), bones (13%), kidneys (13%), mesentery or peritoneum (13%), skin (9%), pancreas (4%), stomach (4%), diaphragm (4%), pituitary gland (2%), ovary (2%), jejunum (2%), axillary lymph nodes (2%), and gingival mucosa (2%). Both distant and regional metastases were present in 23 cases, while only distant metastases were present in 18 cases. An extensive local infiltration of the primary tumor was found in 76% of the cases. The total number of the involved organs and lymph node basins were 123 and 58, respectively. The mean number of metastatic sites was 4.02±2.75. Lung metastases were present in 34 of 38 (89%) of our patients who had distant metastases found at autopsy. Of these 34 patients, 27 were known to have lung metastases when they were alive.

CONCLUSION

Two or more metastatic sites were found at autopsy in 84% of cases. The most common metastatic sites are lungs, followed by the intrathoracic and neck lymph nodes.

Papillary thyroid microcarcinoma with fatal outcome: evidence of tumor progression in lymph node metastases: report of 3 cases, with morphological and molecular analysis

Papillary thyroid microcarcinoma generally carries an excellent prognosis, and fatal cases are becoming increasingly rare. Their pathologic and molecular features, however, remain largely unknown. We describe 3 cases of papillary thyroid microcarcinoma that, despite surgical and radioiodine treatment, recurred, metastasized, and eventually caused the death of the patients. In addition to morphology, immunohistochemical (cyclin D1 and p53) and molecular analyses (BRAF [v-raf Murine sarcoma viral oncogene homolog B1], KRAS [V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog], HRAS [v-Ha-ras Harvey rat sarcoma viral oncogene homolog], NRAS [neuroblastoma RAS viral oncogene homolog], and PIK3CA [phosphoinositide-3-kinase, catalytic, alpha polypeptide]) were performed. Interestingly, all 3 cases presented with massive lymph node metastases that showed morphological evidence of "tumor progression" (tall cell features, poorly differentiated areas, and high-grade cytologic features). Cyclin D1 was consistently immunoreactive in both primary and metastatic site, whereas p53 was negative. BRAF V600E was absent in both sites, and KRAS, HRAS, NRAS, and PIK3CA were consistently wild type. These data suggest that, in cases of metastatic papillary thyroid microcarcinoma, an accurate morphologic analysis of the metastatic deposits could contribute to a more accurate prediction of tumor behavior.

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.

Thyroid Cancer Initially Presenting Compression Fracture without Common Thyroid Symptoms

Thyroid carcinoma is the commonest endocrinological malignancy. After papillary thyroid carcinoma (PTC), follicular thyroid carcinoma (FTC) is the second most common histological subtype. Common presentations of FTC include a solitary thyroid nodule and cervical lymphadenopathy. The incidence of individuals diagnosed with thyroid cancer showing initially distant metastatic disease ranges from 1 to 9%. Also, the incidence of solitary bone metastasis from thyroid is only 2 to 3%. We report a case of a patient with FTC whose initial presentation was low back pain and right buttock pain due to vertebral metastasis rather than the usual neck lumps or symptoms of thyroid disease.

American Thyroid Association guidelines for management of patients with anaplastic thyroid cancer

BACKGROUND

Anaplastic thyroid cancer (ATC) is a rare but highly lethal form of thyroid cancer. Rapid evaluation and establishment of treatment goals are imperative for optimum patient management and require a multidisciplinary team approach. Here we present guidelines for the management of ATC. The development of these guidelines was supported by the American Thyroid Association (ATA), which requested the authors, members the ATA Taskforce for ATC, to independently develop guidelines for ATC.

METHODS

Relevant literature was reviewed, including serial PubMed searches supplemented with additional articles. The quality and strength of recommendations were adapted from the Clinical Guidelines Committee of the American College of Physicians, which in turn was developed by the Grading of Recommendations Assessment, Development and Evaluation workshop.

RESULTS

The guidelines include the diagnosis, initial evaluation, establishment of treatment goals, approaches to locoregional disease (surgery, radiotherapy, systemic therapy, supportive care during active therapy), approaches to advanced/metastatic disease, palliative care options, surveillance and long-term monitoring, and ethical issues including end of life. The guidelines include 65 recommendations.

CONCLUSIONS

These are the first comprehensive guidelines for ATC and provide recommendations for management of this extremely aggressive malignancy. Patients with stage IVA/IVB resectable disease have the best prognosis, particularly if a multimodal approach (surgery, radiation, systemic therapy) is used, and some stage IVB unresectable patients may respond to aggressive therapy. Patients with stage IVC disease should be considered for a clinical trial or hospice/palliative care, depending upon their preference.

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.

Soft tissue metastasis of thyroid carcinoma in the knee region mimicking a paraarticular inflammatory lesion

We report a case of a 57-year-old male patient presenting with a painful mass in the popliteal fossa of the left knee, while the X-ray being unremarkable, MRI suggested a paraarticular lesion such as an inflamed paraarticular ganglion. A biopsy showed a poorly differentiated metastasis of a papillary thyroid carcinoma, the patient had been operated on 8 years ago. This case emphasizes that in patients with malignancies such as papillary thyroid carcinomas long-term courses (over years) with several phases of tumor spread occur finally leading to filiae in any location. Thus, in such patients, a metastatic lesion even in unusual places such as the periarticular soft tissue should be included in the differential diagnosis.

Papillary thyroid carcinoma presenting as an asymptomatic pelvic bone metastases

Thyroid carcinoma is rare comprising 1% of all malignancies and commonly presents as a neck lump. Papillary thyroid carcinoma unlike follicular thyroid carcinoma tends not to metastasise to distant sites. We present a case of papillary thyroid carcinoma presenting as a solitary asymptomatic pelvic bone metastases and highlight current management of bone metastases. A 59-year old female was found on abdominal computerised tomography to have an incidental finding of a 4.5 cm soft tissue mass in the right iliac bone. Biopsy of the lesion confirmed metastatic thyroid carcinoma. There was no history of a neck lump, head and neck examination was normal. Further imaging confirmed focal activity in the right lobe of the thyroid. A total thyroidectomy and level VI neck dissection was performed and histology confirmed follicular variant of papillary carcinoma. Early detection of bone metastases have been shown to improve prognosis and thyroid carcinoma should be considered as a potential primary malignancy.

Prognostic factors and the therapeutic strategy for patients with bone metastasis from differentiated thyroid carcinoma

BACKGROUND

The treatment of bone metastasis in association with thyroid cancer represents a difficult challenge. Given the paucity of patients with bone metastasis and the difficulty of treating this disease, few studies have investigated the clinical features and prognostic factors of bone metastasis from differentiated thyroid cancer.

METHODS

During the 31-year-period from 1976 to 2006, a total of 1,398 patients underwent initial thyroidectomy at Cancer Institute Hospital for differentiated thyroid carcinomas, including standard papillary thyroid carcinoma, papillary microcarcinoma (primary tumor diameter < or =1.0 cm), and follicular thyroid carcinoma. Among these, 25 (2%) patients displayed bone metastasis at initial presentation (synchronous) and 27 patients showed bone metastasis during follow-up (metachronous). The records for these 52 patients were reviewed retrospectively to identify prognostic factors and analyze treatment strategies.

RESULTS

Univariate analysis for disease-specific survival indicated metachronous bone metastasis and the presence of distant metastasis at sites other than bone as indicators of significantly worse prognosis. The type of cancer (papillary thyroid carcinoma versus follicular thyroid carcinoma) was not a significant indicator of prognosis; however, patients with papillary microcarcinoma showed significantly worse survival than patients with standard papillary and follicular thyroid carcinoma. A significant survival advantage was observed among patients who underwent radioactive iodine therapy, and better prognosis seemed to be obtained with greater doses of radioactive iodine. Operative resection of metastatic bone lesions also seemed to be associated with better prognosis. A multivariate analysis for disease-specific survival identified the coexistence of distant metastasis at sites other than bone as the only independent variable indicative of poor prognosis.

CONCLUSION

In the absence of definitive, effective treatments for this disease, radioactive iodine therapy combined with resection of bone metastasis, wherever possible, seems to represent the most potent therapy available. Although bone metastasis is a strong sign of poor prognosis, early detection and administration of appropriate therapy using radioactive iodine seems likely to improve the survival rate and quality of life in patients with bone metastasis from differentiated thyroid carcinoma.

Follicular thyroid carcinoma invades venous rather than lymphatic vessels

Follicular thyroid carcinoma (FTC) tends to metastasize to remote organs rather than local lymph nodes. Separation of FTC from follicular thyroid adenoma (FTA) relies on detection of vascular and/or capsular invasion. We investigated which vascular markers, CD31, CD34 and D2-40 (lymphatic vessel marker), can best evaluate vascular invasion and why FTC tends to metastasize via blood stream to remote organs. Thirty two FTCs and 34 FTAs were retrieved for evaluation. The average age of patients with FTA was 8 years younger than FTC (p = 0.02). The female to male ratio for follicular neoplasm was 25:8. The average size of FTC was larger than FTA (p = 0.003). Fourteen of 32 (44%) FTCs showed venous invasion and none showed lymphatic invasion, with positive CD31 and CD34 staining and negative D2-40 staining of the involved vessels. The average number of involved vessels was 0.88 ± 1.29 with a range from 0 to 5, and the average diameter of involved vessels was 0.068 ± 0.027 mm. None of the 34 FTAs showed vascular invasion. CD31 staining demonstrated more specific staining of vascular endothelial cells than CD34, with less background staining. We recommended using CD31 rather than CD34 and/or D2-40 in confirming/excluding vascular invasion in difficult cases. All identified FTCs with vascular invasions showed involvement of venous channels, rather than lymphatic spaces, suggesting that FTCs prefer to metastasize via veins to distant organs, instead of lymphatic vessels to local lymph nodes, which correlates with previous clinical observations.

Secondary lymphoma involving metastatic follicular thyroid carcinoma to the skull: a unique example of tumor-to-tumor metastasis

Tumor-to-tumor metastases to the skull, presenting as a scalp mass, and thyroid follicular carcinoma presenting in that location are extremely rare. We present the case of a patient with recently diagnosed retroperitoneal diffuse large B-cell lymphoma and an 8-year history of a non-tender large scalp-based mass. The scalp mass was an osteolytic enhancing lesion on imaging studies and diagnosed as metastatic thyroid carcinoma to the skull. The patient had no pre-existing history of thyroid cancer. This metastatic carcinoma was also secondarily involved with diffuse large B-cell lymphoma. This case illustrates a unique and previously unreported example of tumor-to-tumor metastasis in which both malignancies represent metastatic tumors to the skull with soft tissue extension presenting as a large scalp mass.

Detection of bone metastases in thyroid cancer patients: bone scintigraphy or 18F-FDG PET?

BACKGROUND

Similar to the situation in other tumour types, it is currently unclear whether fluorodeoxyglucose (FDG) positron emission tomography (PET) is adequate in the detection of bone metastases of thyroid cancer. The purpose of this retrospective study was to evaluate the performance of bone scans in comparison with FDG PET in the detection of bone metastases in patients with differentiated thyroid cancer (DTC).

MATERIALS AND METHODS

Twenty-four patients had undergone both FDG PET and bone scans within 6 months because of suspected bone metastases. All scans were re-evaluated using all available additional imaging and clinical data for verification. Scan findings were scored as positive, negative or doubtful.

RESULTS

Bone metastases were present in eight of 24 (33%) patients. Only bone scintigraphy but not FDG PET suggested the presence of bone metastases in three patients, all confirmed with magnetic resonance imaging (MRI)/X-ray. Five patients were identified with bone metastases on both bone scan and FDG PET, which was confirmed by computed tomography (CT)/MRI/X-ray in four. Five patients had doubtful findings on bone scans whereas FDG PET scans were negative. MRI showed degenerative disorders in two of five and was normal in two. Eleven patients had both a negative bone scan and FDG PET scan.

CONCLUSION

In three of eight (38%) thyroid cancer patients bone metastases were only identified on bone scans. Therefore, bone scans are still valuable in detecting bone metastases in patients with DTC and can not be replaced by FDG PET.

Clinical features of bone metastases resulting from thyroid cancer: a review of 28 patients over a 20-year period

Bone is the second most frequent site of metastasis resulting from thyroid cancer. Many studies have investigated clinical features and prognostic factors of distant metastases stemming from thyroid cancer in Western countries. The purpose of this study was to review clinical characteristics of Korean patients with bone metastasis originating from thyroid cancer. Between January 1985 and August 2004, 28 patients with thyroid cancer were diagnosed with bone metastases at the Yonsei Severance Hospital in Seoul, Korea. Their clinical characteristics were analyzed retrospectively. Incidence of bone metastasis from follicular thyroid cancer was 6.8% (9 of 132 patients), and 0.4% (13 of 3,154 patients) from papillary thyroid cancer, with an odds ratio of 17.67 (95% confidence interval; 7.41-42). Twelve patients had no symptoms of bone metastasis. Overall mean number of metastasis sites was 2.6 +/- 1.9, and 12 patients had a solitary bone metastasis. Survival rates between the synchronous and metachronous metastasis groups were not significantly different, and the number of metastasis sites did not affect survival. However, the survival of patients that underwent curative treatment was longer than those with palliation (P = 0.0317). In Korea, the overall incidence of bone metastasis resulting from thyroid cancer was less than our expectation. Many patients were asymptomatic, and had a tendency of undergoing less aggressive or palliative treatment, even though the long-term survival of distant metastasis resulting from thyroid cancer with active treatment is relatively good. Further studies of the prognostic factors and effectiveness of various treatments of these patients are needed to enhance survival.

The prognostic value of primary tumor size in papillary and follicular thyroid carcinoma

BACKGROUND

A delay in the diagnosis of differentiated thyroid carcinoma often leads to larger tumors, higher prevalence rates of distant metastasis, and earlier cause-specific deaths. Threshold tumor diameters for extrathyroidal growth, lymph node spread, and distant metastasis in papillary (PTC) and follicular thyroid carcinoma (FTC) remain to be defined.

METHODS

A comparative correlation of primary tumor size and extrathyroidal growth, lymph node spread, and distant metastasis was performed for 500 institutional patients who received surgery for PTC or FTC.

RESULTS

There were 366 patients with PTC (73.2%) and 134 patients with FTC (26.8%). Multifocality (23.5% vs. 9.0%; P < 0.001) and lymph node metastasis (40.2% vs. 19.4%; P < 0.001) were more common in the patients with PTC than in those with FTC. Patients with FTC were older at first diagnosis (51.6 vs. 47.0 years; P = 0.01) compared with the patients with PTC. The FTC tumors were almost twice as large (39.9 vs. 20.6 mm; P < 0.001), and patients had a higher prevalence of distant metastasis (17.9% vs. 6.3%; P < 0.001). When primary tumor diameter was accounted for, cumulative risks of extrathyroidal growth and lymph node metastasis were higher in patients with PTC than in patients with FTC (P < 0.001; log-rank test). In striking contrast, the cumulative risk of distant metastasis was the same for PTC and FTC tumors of equal size (P = 0.89; log-rank test) and increased once the primary tumor size was > 20 mm. Pulmonary metastasis was an earlier event than bone metastasis.

CONCLUSIONS

The data suggested that earlier intervention is warranted to keep suspicious thyroid nodules from growing > 20 mm (or greater than T1) and spreading to distant organs.

Factors influencing the basal and recombinant human thyrotropin-stimulated serum thyroglobulin in patients with metastatic thyroid carcinoma

The serum thyroglobulin (Tg) level is the most sensitive marker for detecting residual thyroid carcinoma. We hypothesized that the basal and TSH-stimulated Tg levels in patients with metastatic thyroid carcinoma would reflect tumor volume, histological subtype, and location of metastatic lesions. A retrospective review of 417 thyroid cancer survivors undergoing evaluation for residual disease with the assistance of recombinant human TSH (rhTSH) was performed. In 169 patients with metastatic disease, we found that the basal Tg level directly correlated with the number of lesions, and that it was highest in patients with follicular and lowest in those with papillary thyroid carcinoma. The basal Tg level was highest in patients with bone metastases and lowest in those with cervical metastases. The fold increase in the serum Tg after rhTSH treatment was highest in papillary thyroid carcinoma and lowest in Hurthle cell carcinoma. The fold increase in Tg was not influenced by tumor volume or by the site of metastatic lesions. Multivariate analysis showed multiple interactions between factors, but did not identify one factor that significantly influenced basal Tg or fold increase. We conclude that the location and volume of metastases influence basal Tg, but not its responsiveness to rhTSH, whereas the histological type of carcinoma influences both basal Tg and responsiveness to rhTSH.

Cutaneous manifestations of thyroid cancer: a report of four cases and review of the literature

Cutaneous metastases from thyroid carcinoma are rare. This report describes four cases of thyroid carcinoma metastatic to the skin. Two cases were medullary carcinoma and two were papillary thyroid carcinoma. In two cases, skin metastases were the presenting feature of the underlying thyroid carcinoma. Examination of the skin lesions by conventional light microscopy suggested the possibility of metastatic carcinoma and immunohistochemical tests confirmed the diagnosis. Subsequent investigations identified primary thyroid lesions. In two cases, the skin metastasis was the first evidence of the recurrence of known thyroid carcinoma. These cases identify a novel presentation of thyroid carcinoma.

Differentiated thyroid carcinomas with vascular invasion: a comparative study of follicular, Hürthle cell and papillary thyroid carcinoma

AIM

Non-medullary thyroid carcinomas arise from follicular cells. The purpose of this study is to correlate clinical and pathological properties of these tumours with the rate of distant metastasis from a series of thyroid tumours excised at one institution.

METHODS

A total of 311 non-medullary thyroid tumours were identified and divided into: 29 follicular carcinoma (FC), 12 Hürthle cell carcinoma (HC), 13 Hürthle cell papillary thyroid carcinoma (HPTC) with vascular invasion (VI), 32 papillary thyroid carcinoma (PTC) with VI and 225 PTC without VI. The mean follow-up was 6.5 years with a range of 1-17 years. The tumours were histologically subdivided into minimal or wide invasion for FC and HC and focal or extensive invasion for PTC and HPTC, and stratified according to status of VI.

RESULTS

The rate of distant metastasis was similar for FC, malignant Hürthle cell tumours and PTC with VI, and increased with extent of invasion. VI was seen in 12% of all PTC and 0% of HPTC in this study. PTC without VI were associated with a much lower potential of distant metastasis, were smaller in size and occurred in patients of younger age than PTC with VI. In addition, there was a tendency for increased potential for distant metastases with increased tumour size and patient age for all groups of tumours in the study. Patient age and tumour size appeared to play a smaller role than that of VI in predicting distant metastasis.

CONCLUSIONS

Our study suggests that the rate of distant metastasis relates to VI, patient age and tumour size, regardless of Hürthle cell, FC or PTC differentiation. PTC of large size, and in patients older than 45 years, have a high propensity for vascular invasion.

Anatomical distribution and sclerotic activity of bone metastases from thyroid cancer assessed with F-18 sodium fluoride positron emission tomography

Currently, bone scintigraphy (BS) is considered to lack sensitivity in detecting bone metastases (BM) from thyroid cancer. We evaluated the anatomical distribution and metabolic behavior of BM as well as the accuracy of BS with and without combination of whole-body iodine scintigraphy (WBI) in detecting metastatic bone disease in thyroid carcinoma. F-18 positron emission tomography (PET), x-ray, BS, and WBI were performed in 35 patients with known or suspected bone metastases from papillary (9 patients) or follicular (26 patients) thyroid carcinoma. Twenty-two metastases were previously known in 14 patients. The indication was staging in 21 patients with high risk for BM, elevated thyroglobulin (Tg)-levels or evaluation of exact extent of BM (14 patients). In addition, results of WBI (35 patients), X-ray (35 patients) F-18 PET (35 patients), MRI of the spine (13 patients), and FDG-PET (15 patients) as well as the clinical course (1.5-4 years) were correlated. BM were detected in 18 patients. Solitary, bifocal, or multiple lesions were present in 9, 2, and 7 patients, respectively. The anatomical distribution of BM (n = 43) was as follows: spine, 42%; skull, 2%; thorax, 16%; femur, 9%; pelvis, 26%; humerus and clavicle, 5%. Sensitivity of BS in interpreting patients as positive or negative for having BM was 64%-85% (specificity, 95%-81%). The combination of BS and WBI was 100% sensitive in detecting metastatic bone disease. One patient had a single BM that was positive at BS but negative on WBI. All metastases were osteolytic on x-ray and two-thirds presented a missing or very limited osteosclerotic bone reaction on F-18 PET. Our data confirm the limited sensitivity of planar BS in detecting BM from thyroid cancer. The combination of BS and WBI, however, was highly accurate. Compared to other malignancies, the distribution pattern of BM presented a lower percentage of vertebral metastases and more patients with single metastases. Those findings in combination with a missing or only slight osteosclerotic bone reaction explain the limited sensitivity of planar BS alone.