Current treatment modalities for spinal metastases secondary to thyroid carcinoma

Ultrasound-guided core needle biopsy combined with immunohistochemistry and molecular testing improve the diagnostic accuracy of bone metastases from follicular thyroid carcinoma, two case reports and analyses

Key Clinical Message

Ultrasound-guided core needle biopsy combined with immunohistochemistry and molecular testing could improve the diagnostic accuracy of bone metastases from follicular thyroid carcinoma, help to predict distant metastasis and prognosis.

Abstract

Metastatic thyroid follicular carcinoma presenting initially with bone lesion is uncommon, its prime symptom is gradual onset, localized pain. Patient with bone metastasis who were diagnosed before thyroidectomy had a higher rate of mortality, clinician should be cautious in eliciting the clinical history and this insidious symptom in middle age group, carry out further examination. We are presenting two case reports of a follicular thyroid carcinoma with bone metastasis, ultrasound-guided core needle biopsy combined with immunohistochemistry (IHC) were carried out by our clinical team to determine the source and nature of the tumor, relevant literature was reviewed, molecular testing was discussed, we believe core needle biopsy combined with IHC and molecular testing improve the diagnostic accuracy of bone metastases from follicular thyroid carcinoma.

Surgical management of spinal metastases from primary thyroid carcinoma: Demographics, clinical characteristics, and treatment outcomes - A retrospective analysis

Objective

Metastatic spinal tumors represent a rare but concerning complication of primary thyroid carcinoma. We identified demographics, metastatic features, outcomes, and treatment strategies for these tumors in our institutional cohort.

Materials and Methods

We retrospectively reviewed patients surgically treated for spinal metastases of primary thyroid carcinoma. Demographics, tumor characteristics, and treatment modalities were collected. The functional outcomes were quantified using Nurik, Modified Rankin, and Karnofsky Scores.

Results

Twelve patients were identified who underwent 17 surgeries for resection of spinal metastases. The primary thyroid tumor pathologies included papillary (4/12), follicular (6/12), and Hurthle cell (2/12) subtypes. The average number of spinal metastases was 2.5. Of the primary tumor subtypes, follicular tumors averaged 2.8 metastases at the highest and Hurthle cell tumors averaged 2.0 spinal metastases at the lowest. Five patients (41.7%) underwent preoperative embolization for their spinal metastases. Seven patients (58.3%) received postoperative radiation. There was no significant difference in progression-free survival between patients receiving surgery with adjuvant radiation and surgery alone (P = 0.0773). Five patients (41.7%) experienced postoperative complications. Two patients (16.7%) succumbed to disease progression and two patients (16.7%) experienced tumor recurrence following resection. Postsurgical mean Nurik scores decreased 0.54 points, mean Modified Rankin scores decreased 0.48 points, and mean Karnofsky scores increased 4.8 points.

Conclusion

Surgery presents as an important treatment modality in the management of spinal metastases from thyroid cancer. Further work is needed to understand the predictive factors for survival and outcomes following treatment.

The Evolving Treatment Landscape of Medullary Thyroid Cancer

OPINION STATEMENT

Genetic assessment is crucial to address the correct treatment for advanced medullary thyroid cancer (MTC). Multi tyrosine kinase inhibitors (mTKIs) cabozantinib and vandetanib are good first line options, even vandetanib prescription is currently limited to RET mutated patients. Selective RET inhibitors such as pralsetinib could be a preferred upfront treatment in case of RET mutated MTC presenting common or gatekeeper RET mutations (e.g. M918T; V804L/M). Selpercatinib, otherwise, can be prescribed as the second line after disease progression to mTKIs. The best option for subsequent lines is to consider inclusion in clinical trials or alternatively other mTKIs such as sunitinib, sorafenib, lenvatinib, or pazopanib could be evaluated. New perspectives include next-generation RET inhibitors able to overcome resistance mechanisms responsible for disease progression to standard mTKIs and RET inhibitors, and immunotherapy for MTC presenting with high tumor mutational burden.

Metastasectomy of spinal lesions from thyroid carcinomas

Patients with differentiated thyroid carcinomas (DTCs) have a favourable long-term survival. Spinal metastases (SMs) cause a decline in performance status (PS), directly affecting mortality and indirectly preventing the use of systemic therapies. Metastasectomy is indicated, if feasible, as it yields the best local tumour control. Our study aimed to examine the long-term clinical outcomes of metastasectomy for SMs of thyroid carcinomas. We collected data on 22 patients with DTC (16 follicular and six papillary carcinomas) and one patient with medullary carcinoma who underwent complete surgical resection of SMs at our institution between July 1992 and July 2017, with a minimum postoperative follow-up of five years. The cancer-specific survival (CSS) from the first spinal metastasectomy to death or the last follow-up was determined using Kaplan-Meier analysis. Potential factors associated with survival were evaluated using the log-rank test. We analyzed the clinical parameters and outcome data, including pre- and postoperative disability (Eastern Cooperative Oncology Group PS 3), lung and non-spinal bone metastases, and history of radioiodine and kinase inhibitor therapies. Lung and other bone metastases at the time of surgery were observed in ten and eight patients, respectively. Three patients experienced local tumour recurrences at the operated site. The five- and ten-year CSS rates in the 22 patients with DTC were 77% and 52%, respectively. Pre- and postoperative disability and operative site tumour recurrence were identified as risk factors for short postoperative survival. Metastasectomy for resectable SM from DTC yielded favourable results and has the potential to improve survival.

Prognosis of thyroid carcinoma patients with osseous metastases: an SEER-based study with machine learning

OBJECTIVE

Osseous metastasis (OM) is the second most common site of thyroid cancer distant metastasis and presents a poor prognosis. Accurate prognostic estimation for OM has clinical significance. Ascertain the risk factors for survival and develop an effective model to predict the 3-year, 5-year overall survival (OS) and cancer-specific survival (CSS) for thyroid cancer patients with OM.

METHODS

We retrieved the information of patients with OMs between 2010 and 2016 from the Surveillance, Epidemiology, and End Result Program. The Chi-square test, and univariate and multivariate Cox regression analyses were performed. Four machine learning (ML) algorithms, which were most commonly used in this field, were applied.

RESULT

A total of 579 patients having OMs were eligible. Advanced age, tumor size ≥ 40 mm, combined with other distant metastasis were associated with worse OS in DTC OMs patients. Radioactive iodine (RAI) significantly improved CSS in both males and females. Among four ML models [logistic regression, support vector machines, extreme gradient boosting, and random forest (RF)], RF had the best performance [area under the receiver-operating characteristic curve: 0.9378 for 3-year CSS, 0.9105 for 5-year CSS, 0.8787 for 3-year OS, 0.8909 for 5-year OS]. The accuracy and specificity of RF were also the best.

CONCLUSIONS

RF model shall be used to establish an accurate prognostic model for thyroid cancer patients with OM, not only from the SEER cohort but also intended for all thyroid cancer patients in the general population, which may be applicable in clinical practice in the future.

Follicular carcinoma of the thyroid with a single metastatic lesion in the lumbar spine: A case report

BACKGROUND

The bone is the second most common site of thyroid cancer metastasis, after the lung. Treatment options for bone metastasis of thyroid cancer include surgery, radioiodine therapy (RAIT), external radiation therapy, thyroid-stimulating hormone (TSH) inhibition, bisphosphonates, and small-molecule targeted therapies. In most cases, thyroid carcinoma is found in the thyroid tissue; reports of follicular thyroid carcinoma with a single metastasis to the lumbar spine are rare.

CASE SUMMARY

We report a case of bone metastasis as the only clinical manifestation of thyroid cancer. The patient was a 67-year-old woman with lumbar pain for 7 years and aggravation with intermittent claudication who had previously undergone partial thyroidectomy of a benign thyroid lesion. No abnormal nodules were found in the bilateral thyroid glands. However, imaging studies were consistent with a spinal tumor, and the lesion was diagnosed as a metastatic follicular carcinoma of thyroid origin. We adopted a multidisciplinary collaboration and comprehensive treatment approach. The patient underwent lumbar spine surgery, total resection of the thyroid, postoperative TSH suppression therapy, and RAIT. There were no complications associated with the operation, and the patient had good postoperative recovery. She has experienced no recurrence.

CONCLUSION

Follicular thyroid carcinoma is associated with early hematogenous metastasis, and the bone is a typical site of metastasis. Single bone metastasis is not a contraindication to medical procedures, and providing the appropriate therapy can result in better outcomes and quality of life for these patients.

Parthenolide leads to proteomic differences in thyroid cancer cells and promotes apoptosis

Background

Parthenolide has anti-inflammatory, immunomodulatory and anti-cancer activities. But its effect on thyroid cancer cells is still largely unknown.

Methods

Label-free quantitative proteomics and bioinformatics analysis were used to investigate the differentially expressed proteins and their functions in thyroid cancer treated with parthenolide and control pair. Hoechst 33258 fluorescent staining and Annexin V-FITC/PI double staining flow cytometry were used to detected BCPAP cells apoptosis. Parallel reaction monitoring (PRM) and quantitative real-time PCR were used to verify the expression of apoptosis-related differential proteins and their mRNA.

Results

Sixty up-regulated and 96 down-regulated differentially expressed proteins were identified in parthenolide treated thyroid cancer cells BCPAP compared with control thyroid cancer cells. The proteins were mainly relevant to various biological processes that included metabolic processes, response to extracellular stimulus and interaction with host. The molecular functions of most differentially expressed proteins were associated with binding functions and nucleotidyltransferase activity. According to the Kyoto Encyclopedia of Genes and Genomes, the differentially expressed proteins identified are primarily related to various types of metabolic pathways and DNA replication. In cell experiments in vitro, with the increase of the dose of parthenolide, the number of cells gradually decreased, the apoptosis rate gradually increased. PRM verified that the apoptosis-related proteins HMOX1 and GCLM were up-regulated and IL1B was down-regulated in BCPAP cells treated with parthenolide. The mRNA expressions of HMOX1, GCLM, ITGA6 and CASP8 were up-regulated and HSPA1A was down-regulated by PCR.

Conclusions

Parthenolide may influence the biological behavior of human thyroid cancer cells by affecting the expression of proteins related to cell metabolism and DNA replication. Parthenolide induced significant cellular morphological changes and apoptosis in human thyroid cancer cells, leading to an anti-proliferative effect.

The role of surgery in the treatment of metastatic bone tumor

Surgery for bone metastasis has two primary goals-palliative care to relieve pain, instability and paralysis, and tumor resection for curing the disease. Oncologically en bloc resection, followed by a reconstruction of the bone defect is the treatment of choice in single bone metastasis from renal cell carcinoma or thyroid cancer. Bone metastases may occur in the extremities, pelvis, or spine, and different resection and reconstruction methods depend on the regional anatomy. For instance, multiple options are available for reconstruction of the pelvis, especially for the acetabulum, including anatomical reconstruction using custom-made implants or recycled autologous bone grafting when a long-term prognosis is expected. Recently, for the spine, total en bloc spondylectomy is extensively performed despite the initial limitations of surgical invasiveness, such as blood loss. Principally, palliative surgery aims to maintain lasting bony stability with minimal surgical invasiveness. Intramedullary nails and plate fixation are frequently used in the extremities but the postoperative failure rate is relatively high. Therefore, surgeons should consider the use of long intramedullary nails and long-type stems for endoprosthesis reconstruction along with cement fixation to reduce the failure rate. Although short-term complications, such as dislocation, have been observed with endoprosthesis reconstruction, it is stable in the long-term follow-up. Percutaneous bone cement injection into the spine and pelvis is also effective and less invasive.

Radioiodine Refractory Differentiated Thyroid Cancer

Patients with radioactive iodine (RAI) refractory locally advanced or metastatic differentiated thyroid cancer have a poor prognosis. This article reviews the definition of RAI-refractory thyroid cancer and the management approach. Watchful waiting should be considered for patients with asymptomatic and non-progressive disease, while oral targeted agent with tyrosine kinase inhibitors can be considered for patients who are symptomatic or whose disease would cause irreversible complications if treatment has not been initiated. Since these targeted agents only improve disease-free survival and are associated with adverse events, physicians should assess both clinical and tumor factors carefully to decide on the right timing of start of palliative treatment.

Endocrine Regulation on Bone by Thyroid

BACKGROUND

As an endocrine organ, the thyroid acts on the entire body by secreting a series of hormones, and bone is one of the main target organs of the thyroid.

SUMMARY

This review highlights the roles of thyroid hormones and thyroid diseases in bone homeostasis.

CONCLUSION

Thyroid hormones play significant roles in the growth and development of bone, and imbalance of thyroid hormones can impair bone homeostasis.

Spinal metastases from thyroid cancer: Some prognostic factors

BACKGROUND

Spinal metastases (SpMs) from thyroid cancers (TC) significantly reduce quality of life by causing pain, neurological deficits in addition to increasing mortality. Moreover, prognosis factors including surgery remain debated.

METHODS

Data were stored in a prospective French national multicenter database of patients treated for SpM between January 2014 and 2017. Fifty-one consecutive patients affected by TC with 173 secondary SpM were included.

RESULTS

Mean overall survival (OS) time for all patients from the diagnosis of a thyroid SpM event was 9.1 years (SD 8.7 months). The 1-year, 5-year and 10-year survival estimates were 94% (SD 3.3), 83.8.0% (SD 5.2), and 74.5% (SD 9.9). The median period of time between primary thyroid tumor diagnosis and the SpM event was 31.4 months (SD 71.6). In univariate analysis, good ECOG-PS (status 0 and 1) (p < 0.0001), ambulatory status (Frankel score) (p < 0.0001) and no epidural involvement (p = 0.01), were associated with longer survival, whereas cancer subtype (p = 0.436) and spine surgery showed no association (p = 0.937). Cox multivariate proportional hazard model only identified good ECOG-PS: 0 [HR: 0.3, 95% CI 0.1-0.941; p < 0.0001], 1 [HR: 0.8, 95% CI 0.04-2.124; p = 0.001] and ambulatory neurological status: Frankel E [HR: 0.262, 95% CI 0.048-1.443; p = 0.02] to be independent predictors of better survival.

CONCLUSION

For cases presenting SpM from TC, we highlighted that the only prognostic factors were the progression of the cancer (ECOG-PS) and the clinical neurological impact of the SpM (Frankel status). Surgery should be discussed mainly for stabilization and neurological decompression.

Current Management of Bone Metastases from Differentiated Thyroid Cancer

Simple Summary

Patients with bone metastases (BMs) from differentiated thyroid carcinoma (DTC) can live longer than those with BMs from other cancers. BMs from DTC create destructive lesions and easily cause intractable pain and neurological symptoms, including paralysis. These symptoms related to BMs affect mortality directly and indirectly by hampering the application of systemic therapies. Therefore, long-term local control of BMs in patients with DTC is desired, especially in patients with single or a small number of metastases. Local treatments for BMs have recently become advanced and sophisticated in surgery, radiotherapy, and percutaneous procedures. These therapies, either alone or in combination with other treatments, can effectively improve, or prevent the deterioration of, the performance status and quality of life of patients with DTC-BM. Among local therapies, complete surgical resection and stereotactic radiosurgery are the mainstay for achieving long-term control of DTC-BM.

Abstract

After the lung, the skeleton is the second most common site of distant metastases in differentiated thyroid carcinoma (DTC). Patients with osteolytic bone metastases (BMs) from thyroid carcinoma often have significantly reduced performance status and quality of life. Recent advancements in cancer therapy have improved overall survival in multiple cancer subtypes, including thyroid cancer. Therefore, long-term local control of thyroid BMs is desired, especially in patients with a single metastasis or oligometastases. Here, we reviewed the current management options for DTC-BMs and especially focused on local treatments for long-term local tumor control from an orthopedic tumor surgeon’s point of view. Metastasectomy and stereotactic radiosurgery can be performed either alone or in combination with radioiodine therapy and kinase inhibitors to cure skeletal lesions in selected patients. Percutaneous procedures have been developed in recent years, and they can also have a curative role in small BMs. Recent advancements in local therapies have the potential to provide not only long-term local tumor control but also a better prognosis.

Perioperative complications of total en bloc spondylectomy for spinal tumours

AIMS

To evaluate the perioperative complications associated with total en bloc spondylectomy (TES) in patients with spinal tumours, based on the extent and level of tumour resection.

METHODS

In total, 307 patients who underwent TES in a single centre were reviewed retrospectively. There were 164 male and 143 female patients with a mean age at the time of surgery of 52.9 years (SD 13.3). A total of 225 patients were operated on for spinal metastases, 34 for a malignant primary tumour, 41 for an aggressive benign tumour, and seven with a primary of unknown origin. The main lesion was located in the thoracic spine in 213, and in the lumbar spine in 94 patients. There were 97 patients who underwent TES for more than two consecutive vertebrae.

RESULTS

Major and minor perioperative complications were observed in 122 (39.7%) and 84 (27.4%) patients respectively. The breakdown of complications was as follows: bleeding more than 2,000 ml in 60 (19.5%) patients, hardware failure in 82 (26.7%), neurological in 46 (15.0%), surgical site infection in 23 (7.5%), wound dehiscence in 16 (5.2%), cerebrospinal fluid leakage in 45 (14.7%), respiratory in 52 (16.9%), cardiovascular in 11 (3.6%), digestive in 19 (6.2%)/ The mortality within two months of surgery was four (1.3%). The total number of complications per operation were 1.01 (SD 1.0) in the single vertebral resection group and 1.56 (SD 1.2) in the group with more than two vertebral resections. Cardiovascular and respiratory complications, along with hardware failure were statistically higher in the group who had more than two vertebrae resected. Also, in this group the amount of bleeding in patients with a lumbar lesion or respiratory complication in patients with a thoracic lesion, were statistically higher. Multivariate analysis showed that using a combined anterior and posterior approach, when more than two vertebral resections were significant independent factors.

CONCLUSION

The characteristics of perioperative complications after TES were different depending on the extent and level of the tumour resection. In addition to preoperative clinical and pathological factors, it is therefore important to consider these factors in patients who undergo en bloc resection for spinal tumours. Cite this article: Bone Joint J 2021;103-B(5):976-983.

Bone metastases from differentiated thyroid carcinoma: current knowledge and open issues

Bone represents the second most common site of distant metastases in differentiated thyroid cancer (DTC). The clinical course of DTC patients with bone metastases (BM) is quite heterogeneous, but generally associated with low survival rates. Skeletal-related events might be a serious complication of BM, resulting in high morbidity and impaired quality of life. To achieve disease control and symptoms relief, multimodal treatment is generally required: radioiodine therapy, local procedures-including surgery, radiotherapy and percutaneous techniques-and systemic therapies, such as kinase inhibitors and antiresorptive drugs. The management of DTC with BM is challenging: a careful evaluation and a personalized approach are essential to improve patients' outcomes. To date, prospective studies focusing on the main clinical aspects of DTC with BM are scarce; available analyses mainly include cohorts assembled over multiple decades, small samples sizes and data about BM not always separated from those regarding other distant metastases. The aim of this review is to summarize the most recent evidences and the unsolved questions regarding BM in DTC, analyzing several key issues: pathophysiology, prognostic factors, role of anatomic and functional imaging, and clinical management.

Prognostic Factors in Patients with Differentiated Thyroid Cancers Metastatic to the Cervical Spine

OBJECTIVES

The spine is the most common site of bone metastases in differentiated thyroid cancer (DTC). The role of surgery in the management of cervical spine (C-spine) metastases (CSpM) has not been adequately explored.

METHODS

This is a retrospective cohort study at a tertiary referral center from 2002 to 2018. Inclusion criteria were pathologic diagnosis of DTC and imaging/pathologic diagnosis of CSpM. Statistical analysis utilized t tests for continuous variables and χ² tests for categorical variables. Survival analysis was conducted using Kaplan-Meier curves with univariate and multivariate Cox regressions.

RESULTS

Fifty patients with DTC and CSpM were identified. Of those, 16 underwent surgical resection of the C-spine, whereas 34 did not. The most common presenting symptom was neck pain (N = 37, 74%). Patients in the surgery group were more likely to report a subjective improvement of symptoms (P < .01) and to have local (P < .01) and systemic (P = .04) disease control. Five-year overall survival was 44.7% for the surgery group (95% confidence interval [CI]: 17.1-69.3) and 11.1% (95% CI: 2.1-28.8) for the nonsurgery group (P = .01). The strongest risk factor for improved overall survival after C-spine metastasis was local disease control at the C-spine (multivariate hazard ratio [HR] = 0.32, 95% CI: 0.12-0.85, P = .02). Surgical intervention was significantly associated with improved survival on both univariate (HR = 0. 35, 95% CI: 0.15-0.82, P = .02) and multivariate (HR = 0.37, 95% CI: 0.14-0.98, P = .04) analysis.

CONCLUSION

Surgical management of CSpM in differentiated thyroid cancers is associated with significantly improved local disease control and overall survival. Referral to spine surgeons should be considered after diagnosis.

LEVEL OF EVIDENCE

IV. Laryngoscope, 131:E1741-E1747, 2021.

Contemporary Debates in Adult Papillary Thyroid Cancer Management

An ever-increasing population of patients with papillary thyroid cancer is engaging with health care systems around the world. Numerous questions about optimal management have arisen that challenge conventional paradigms. This is particularly the case for patients with low-risk disease, who comprise most new patients. At the same time, new therapies for patients with advanced disease are also being introduced, which may have the potential to prolong life. This review discusses selected controversial issues in adult papillary thyroid cancer management at both ends of the disease spectrum. These topics include: (i) the role of active surveillance for small papillary cancers; (ii) the extent of surgery in low-risk disease (lobectomy vs total thyroidectomy); (iii) the role of postoperative remnant ablation with radioiodine; (iv) optimal follow-up strategies in patients, especially those who have only undergone lobectomy; and (v) new therapies for advanced disease. Although our current management is hampered by the lack of large randomized controlled trials, we are fortunate that data from ongoing trials will be available within the next few years. This information should provide additional evidence that will decrease morbidity in low-risk patients and improve outcomes in those with distant metastatic disease.

MOLECULAR PROFILE AND CLINICAL OUTCOMES IN DIFFERENTIATED THYROID CANCER PATIENTS PRESENTING WITH BONE METASTASIS

Objective: Differentiated thyroid cancer patients uncommonly present with bone metastasis as the initial manifestation. Their molecular profile is largely unknown. The aim of this study was to evaluate the histopathology, molecular profiles, and response to radioactive iodine therapy in these patients. Methods: Eight patients presented with symptomatic bone metastasis from an unknown primary tumor. We identified these patients by performing a retrospective chart review. Pathology slides were reviewed and the molecular analysis of 112 thyroid cancer-related genes was performed on bone metastasis specimens using targeted next-generation sequencing. Results: These patients presented with long bone fractures, spinal cord compression, or intractable bone pain. Histopathologic analysis of the bone and thyroid tumor specimens revealed follicular variant of papillary carcinoma in 7 patients and tall cell variant papillary carcinoma in 1 patient. Primary tumor size ranged from 0.4 to 7.5 cm. All patients received high dose radioiodine therapy following thyroidectomy. Molecular analysis revealed telomerase reverse transcriptase (TERT) mutations in 7 (88%) tumors, 4 (50%) contained co-occurring TERT and RAS GTPase gene (RAS) mutations, 2 had isolated TERT mutations, and 1 had TERT and proto-oncogene B-Raf (BRAF) V600E mutations, respectively. Tumors carrying RAS, TERT, or a combination of these mutations were radioiodine-avid, with predictable tumor response and reduction in serum thyroglobulin levels. One patient with radioiodine-refractory disease harbored BRAF and TERT mutations. Conclusion: These results demonstrate that differentiated thyroid cancers presenting with bone metastasis independent of the primary tumor size have a high prevalence of TERT mutations, frequently coexisting with RAS mutations. This molecular signature may predict a favorable response to radioiodine therapy. Abbreviations: BRAF = proto-oncogene B-Raf; DNA = deoxyribonucleic acid; DTC = differentiated thyroid cancer; FV = follicular variant; PTC = papillary thyroid carcinoma; RAI = radioactive iodine; RAS = Ras GTPase gene; TERT = telomerase reverse transcriptase; TG = thyroglobulin.

Surgical Management and Factors Affecting the Prognosis for Patients with Thyroid Cancer Spinal Metastases: A Retrospective Analysis of 52 Consecutive Patients from a Single Center

BACKGROUND

Thyroid cancer, one of the most common endocrine malignancies in developed areas and China, is associated with favorable prognosis. However, the presence of spinal metastases will remarkably reduce the life expectancy for patients with thyroid cancer. In addition, limited information is available about such disease.

METHODS

Various potential clinical factors were submitted to univariate and multivariate analyses to identify the independent variables that predicted the prognosis for patients. In addition, the survival rate was estimated according to the Kaplan-Meier method, and statistic differences were calculated by the log-rank test. Moreover, factors with a P value of ≤0.1 were performed multivariate analysis using a multivariate Cox proportional hazards model, and factors with a P value of <0.05 were considered as statistically significant.

RESULTS

Seven potential independent prognostic factors had been identified through univariate analysis, which were then subjected to multivariate analysis. Our results suggested that age of ≤50 years, single segment involved, and follicular thyroid cancer were the independent favorable prognostic factors.

CONCLUSIONS

Findings in this study indicate that age of ≤50 years, single segment involved, and follicular thyroid cancer are favorable prognostic factors for patients with thyroid cancer spinal metastases.

Radioiodine refractory differentiated thyroid cancer

Differentiated thyroid cancer (DTC) is usually curable with surgery, radioactive iodine (RAI), and thyroid-stimulating hormone (TSH) suppression. However, local recurrence and/or distant metastases occur in approximately 15% of cases during follow-up, and nearly two-thirds of these patients will become RAI-refractory (RR-DTC) with a poor prognosis. This review focuses on the most challenging and rapidly evolving aspects of RR-DTC, and we discuss the considerable improvement in more accurately defining RR-DTC, more effective therapeutic strategies, and describe the diagnosis, pathogenesis, and future prospects of RR-DTC. Along with the detection of serum thyroglobulin and anatomic imaging modalities, such as ultrasound and computer tomography, radionuclide molecular imaging plays a vital role in the evaluation of RR-DTC. In addition, continual progress has been made in the management of RR-DTC, including watchful waiting under appropriate TSH suppression, local treatment approaches, and systemic therapies (molecular targeted therapy, redifferentiation therapy, gene therapy, and cancer immunotherapy). These all hold promise to change the natural history of RR-DTC.

An upper cervical cord compression secondary to occult follicular thyroid carcinoma metastases successfully treated with multiple radioiodine therapies: A clinical case report

RATIONALE

The spine is the most common site of bone metastases due to thyroid cancer; however, spinal cord compression as a complication of metastatic thyroid cancer is very rare.

PATIENT CONCERNS

A 48-year-old female patient was presented to the Neurosurgical Department, complaining of progressive back neck pain with bilateral upper extremities numbness and weakness for 4 months.

DIAGNOSIS

Imaging studies revealed osteolytic destruction in bodies and accessories of the second and third cervical vertebrae with a huge soft-tissue mass compressing spinal cord and causing swelling. After the neurosurgical decompression surgery, the pathological examination established a metastatic follicular carcinoma originating from the thyroid gland.

INTERVENTIONS

Her cervical spinal metastases were hardly removed by surgery and the risks of external beam radiation therapy (EBRT) were very high. So she underwent a total thyroidectomy and received multiple radioiodine (RAI) and concomitant glucocorticoid therapies postoperatively. Radioiodine whole-body scan (WBS) showed multiple abnormal radioiodine uptakes. Then single-photon emission tomography/computed tomography (SPECT/CT) located these spinal metastases involving cervical, lumbar, and sacral vertebrae.

OUTCOMES

After 5 times RAI therapy, her thyroglobulin obviously decreased, with the cervical lesion shrinkage and no spinal cord edema.

LESSONS

RAI therapy and concomitant glucocorticoid therapy could be used for spinal metastases of FTC, even with spinal cord compression.

Image-guided minimally invasive percutaneous treatment of spinal metastasis

In order to provide effective options for minimally invasive treatment of spinal metastases, the present study retrospectively evaluated the efficacy and safety of image-guided minimally invasive percutaneous treatment of spinal metastases. Image-guided percutaneous vertebral body enhancement, radiofrequency ablation (RFA) and tumor debulking combined with other methods to strengthen the vertebrae were applied dependent on the indications. Percutaneous vertebroplasty (PVP) was used when vertebral body destruction was simple. In addition, RFA was used in cases where pure spinal epidural soft tissue mass or accessories (spinous process, vertebral plate and vertebral pedicle) were destroyed, but vertebral integrity and stability existed. Tumor debulking (also known as limited RFA) combined with vertebral augmentation were used in cases presenting destruction of the epidural soft tissue mass and accessories, and pathological vertebral fractures. A comprehensive assessment was performed through a standardized questionnaire and indicators including biomechanical stability of the spine, quality of life, neurological status and tumor progression status were assessed during the 6 weeks-6 months follow-up following surgery. After the most suitable treatment was used, the biomechanical stability of the spine was increased, the pain caused by spinal metastases within 6 weeks was significantly reduced, while the daily activities and quality of life were improved. The mean progression-free survival of tumors was 330±54 days, and no associated complications occurred. Therefore, the use of a combination of image-guided PVP, RFA and other methods is safe and effective for the treatment of spinal metastases.

Updates on the Management of Advanced, Metastatic, and Radioiodine Refractory Differentiated Thyroid Cancer

Differentiated thyroid cancer (DTC) accounts for 95% of all thyroid cancers and is generally an indolent tumor, treated effectively with surgery, radioactive iodine, and thyroid-stimulating hormone suppressive therapy. However, 5-10% of patients have advanced disease, with aerodigestive tract invasion, distant metastases, or radioiodine refractory disease, with poor prognosis. This review focuses on the approaches for treating advanced DTC, including management of gross extra-thyroidal extension, recurrent loco-regional or distant metastatic disease, the role of external beam radiation therapy and systemic treatment. Locally ablative treatment modalities, including surgery, radiation therapy, and thermal ablation are evolving and can be used in selected patients. In recent years, new therapeutic agents with molecular targets have become available and two multi-kinase inhibitors, Sorafenib and Lenvatinib, have been licensed for iodine refractory DTC showing an advantage in terms of progression-free survival, although an impact on overall survival has not been proven yet. Management of advanced thyroid cancer can be challenging but a multidisciplinary approach can significantly improve outcomes for this patient population.

Local treatment of metastases from differentiated thyroid cancer

OBJECTIVES

To study the various local treatments available for thyroid cancer metastases, investigate techniques and assess their advantages and limitations and roles in the overall treatment strategy for metastatic disease.

RESULTS

We investigated metastases surgery, external radiation therapy, embolization, chemoembolization, cementoplasty, radiofrequency ablation and cryotherapy, describing techniques, advantages and drawbacks and possible complications. Indications were reviewed according to metastases location, and the roles of the various techniques are discussed in the overall treatment strategy for thyroid cancer metastases. Despite the advent of new targeted therapies, local treatment still has an important role to play: either palliative or, in oligometastatic involvement, curative. Even in extensive disease, it may allow postponement of tyrosine kinase inhibitor therapy, which, once initiated, has to be continued life-long, is expensive and is not free of side-effects.

Spine Stereotactic Radiosurgery for Patients with Metastatic Thyroid Cancer: Secondary Analysis of Phase I/II Trials

BACKGROUND

Metastatic deposits to the spine in thyroid cancer patients represent the most common site of bone involvement and can contribute to pain, neurologic deficits, and death. This study sought to determine the efficacy and safety of spine stereotactic radiosurgery (SSRS) for thyroid cancer patients.

METHODS

Thyroid cancer patients with spine metastases were selected and analyzed from a cohort of patients who were prospectively enrolled in two single-institution Phase I/II studies. SSRS was delivered in single or multi-fraction schedules. Dose regimens ranged from 16-18 Gy in one fraction to 27-30 Gy in three to five fractions. Toxicity was graded according to the NCI-CTC toxicity scale. Local control was determined by serial post-treatment magnetic resonance imaging scans showing no evidence of progressive disease. Patients were followed until date of death or date of last known visit for survival analyses. Local control and overall survival rates were carried out using Kaplan-Meier estimates. The log-rank test was used to assess the equality of the survivor function across groups. A p-value of ≤0.05 was considered to be statistically significant.

RESULTS

A total of 27 spine lesions were treated in 23 patients over a six-year period. Median follow-up was 28.9 months (range 5-93 months). Local control was 88% at two years and 79% at three years. In patients with progressive disease following conventional radiation therapy, local control for salvage SSRS remained at 88% at three years. Patients requiring upfront surgical intervention and treated with adjuvant SSRS achieved sustained control rates of 86% at three years. Overall survival rates were 85% and 67% at one and two years, respectively. In patients classified with oligoprogression and controlled extra-spinal disease, overall survival was significantly higher than those with evidence of systemic progression (81% vs. 45% at two years; p = 0.01). Univariate analysis did not show significant correlations between local control and age, systemic disease status, prior (131)I therapy, SSRS fraction regimen, spine location, histological subtype, or time from initial diagnosis to evidence of spinal metastasis. No patient experienced any grade 3-5 toxicity. Pain flare was reported in 30% of patients, with only three patients (13%) requiring narcotics or short-course steroids. There was no evidence of vertebral body fracture in any patient that achieved local control in the treated area.

CONCLUSIONS

SSRS for thyroid metastases as a primary or adjuvant/salvage therapy is well tolerated and yields high rates of local control.

The impact of complete surgical resection of spinal metastases on the survival of patients with thyroid cancer

Spinal metastases (SMs) from thyroid cancers significantly reduce the quality of life by causing pain and neurological deficits and increase mortality. Complete surgical resection of isolated thyroid SMs is a promising treatment option; however, the postoperative outcome is unknown. This study aimed to compare the postoperative courses of patients undergoing complete resection of thyroid SMs with those of patients undergoing incomplete resection, with a minimum 4‐year follow‐up. We performed a retrospective analysis of 32 patients who underwent tumor excision surgery for thyroid SMs at our medical center during a 28‐year period. Twenty patients underwent complete excision, and 12 underwent incomplete excision. Survival was defined as the time from the first spinal surgery to death or last follow‐up. Kaplan–Meier analysis with the long‐rank test was used to compare the overall survival rates between the groups. For all patients, the overall 5‐ and 10‐year survival rates were 71% and 31%, respectively. The median overall survival time was 6.4 years. The patients undergoing complete excision survived longer than those undergoing incomplete excision (5‐year survival: 84% vs. 50%; 10‐year survival: 52% vs. 8%; P < 0.01). Only one patient undergoing complete excision experienced local tumor recurrence in the operated spine, whereas all long‐term survivors (>18 months after surgery) in the incomplete excision group experienced local tumor recurrence and a consequent deterioration in performance status. Complete surgical resection of thyroid SMs, if achievable, has the potential not only to maintain performance status, but also to prolong survival.

Therapeutic options in papillary thyroid carcinoma: current guidelines and future perspectives

The treatment of papillary thyroid cancer is now based on individual patient risk and response to therapies. Molecular techniques are increasingly being used to risk stratify and to guide therapeutic decisions. There have been advances in the treatment of local disease through surgery or radioiodine. Directed techniques can target metastatic disease including bisphosphonates, radiofrequency ablation or radiotherapy. Systemic therapies such as tyrosine kinase inhibitors show great promise although such treatment must be individualized. Future therapies will target treating radioiodine refractory disease.

Isolated Spinal Metastasis with Spinal Cord Compression Leads to a Diagnosis of a Follicular Thyroid Carcinoma

Introduction: Thyroid carcinoma initially presents with clinical symptoms due to metastatic lesions in less than 5% of cases. Spinal cord compression from an epidural metastatic lesion as a first symptom is extremely rare. One would expect such a presentation to occur much later in the course of the disease.

Methods: We are presenting a case report of a follicular thyroid carcinoma that presented with spinal cord compression from a thoracic epidural metastatic lesion in a previously healthy 55-year-old male. A single metastasis of follicular thyroid carcinoma presenting with posterior spinal cord compression is rare. In this particular case, our management included a mid-thoracic laminectomy, followed by resection of the epidural lesion. Once the surgical pathology confirmed the diagnosis of a follicular thyroid carcinoma, the general surgery team performed a near total thyroidectomy, after which he received radioactive iodine therapy. The patient is symptom-free at his three-year follow-up.

Conclusion: Initial presentation of follicular thyroid carcinoma with symptomatic thoracic myelopathy from an epidural metastasis is very uncommon. An early diagnosis and prompt surgical intervention provided an excellent outcome.