Brain metastases from thyroid carcinoma: a retrospective study of 21 patients

Chinese management guidelines for radioactive iodine-refractory differentiated thyroid cancer (2025 edition)

PURPOSE

Radioactive iodine-refractory differentiated thyroid cancer (RAIR-DTC) has become a challenge in clinical practice, particularly in China with a high incidence and undesirable survival outcome. Since the publication of first China consensus on the diagnosis and treatment of RAIR-DTC in 2019, significant and rapid advances have occurred in the field both in China and internationally. This guideline aims to inform Chinese clinicians, researchers, patients, and health policy makers on the latest evidence and recommendations, to further standardize the clinical diagnosis and treatment of RAIR-DTC.

METHODS

The structured clinical questions addressed in this guideline were derived from clinical diagnostic and treatment processes, with references to study, prior guidelines, expert consensus, and systematic reviews, etc. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used for quantitative and qualitative evaluation of the evidence. The editorial process was completely independent of the guideline development group.

RESULTS

The guideline addressed 26 clinical questions and formed 35 recommendations. In this guideline, the definition criteria for RAIR-DTC was optimized, prediction and identification was based on evidence including molecular testing, dynamic biochemical changes, and multimodal imaging. Comprehensive pre-treatment clinical evaluation was emphasized and tailored for individualized decision-making. The combination of systematic therapy and surgery, and the redifferentiation followed by RAI therapy were also reviewed and updated. Molecular imaging plays a unique role in the pre-assessing and therapeutic response evaluation for RAIR-DTC.

CONCLUSIONS

We have updated and developed evidence-based recommendations with the aim of providing scientific, rigorous, and comprehensive guidance for the clinical diagnosis and treatment of RAIR-DTC patients in China. We hope to share our guideline with colleagues out of China, with the expectation of further comments and suggestions.

The Surgical Management of Intracranial Metastasis Secondary to Follicular Cell-Derived Thyroid Carcinoma

BACKGROUND

Intracranial metastases (ICM) from follicular cell-derived thyroid carcinoma (FCDTC) are rare and are associated with a poor prognosis. The objective of this study is to report our experience in the surgical management of patients with ICM secondary to FCDTC.

METHODS

Patients with FCDTC who underwent surgical resection of an ICM were identified at our institution from 1998 to 2018.

RESULTS

Thirty-two patients were included in this study. Nineteen patients (59%) had involvement of the brain parenchyma only, 8 (25%) had a dural-based metastasis, 3 (9%) had a calvarial metastasis with dural extension, and 2 (6%) had a skull base metastasis with dural extension. In patients who had an R0-1 resection, the estimated lesional control at the site of resection was 91% at 3 years. However, overall ICM control was 37% at 3 years due to the progression of other ICM lesions. The 1-year disease-specific survival (DSS) was 87% and 5-year DSS was 37%.

CONCLUSIONS

ICM management in FCDTC is based on the size, number, and location of metastatic lesions. Complete resection of ICM may provide lesional control at the site of resection, however, DSS is poor due to the presence of other ICMs and metastases at multiple distant sites.

Primary Central Nervous System Lymphoma (PCNSL) Following Thyroid Cancer Surgery: A Case Report of Misdiagnosed Brain Metastasis and Literature Review

Objectives: This article reports a rare case of primary central nervous system lymphoma (PCNSL) found in a patient with thyroid cancer after surgery.

METHODS

The patient was initially misdiagnosed with brain metastases, and the diagnosis of PCNSL was later confirmed by pathology.

RESULTS

The analysis of this case and review of the relevant literature explores the possible mechanisms of the coexistence of thyroid cancer and PCNSL, as well as their diagnostic, differential diagnostic, and therapeutic challenges.

CONCLUSIONS

The article suggests a possible correlation between the coexistence of multiple cancers and autoimmune diseases and emphasizes that disease cannot be only considered in a monolithic way.

Le cancer thyroïdien différencié réfractaire à l’iode : quelle prise en charge en 2024 ?

TREATING RADIO-IODINE REFRACTORY DIFFERENTIATED THYROID CANCER IN 2024: About 5 to 10% of patients with differentiated thyroid cancer (DTC) have advanced tumors at presentation or recurrence, with invasive cervical disease and/or distant metastases that cannot be effectively treated by conventional treatment, i.e. thyroid surgery and radioactive iodine. These DTC cases are defined as refractory to radioiodine (RAIR) and require expert multidisciplinary management. In France, patients are referred to centers of the ENDOCAN-TUTHYREF Network. This review summarizes current management of RAIR DTC patients and therapeutic options available in 2024. We discuss following topics : epidemiological data, modalities of local ablative treatment for selected metastatic lesions, molecular tests to be performed, optimum timing for initiating systemic therapy, choice of first-line treatment among validated tyrosine kinase inhibitors (TKIs), alternative targeted treatments (including selective TKIs adapted to the molecular profile, some of which can redifferentiate and restore radioactive iodine uptake), proactive management of TKI side effects, and finally give an overview of systemic strategies. Management of RAIR DTC is still challenging but substantial progress has been made over the last decade that has significantly improved outcome for these more aggressive thyroid cancer.

Brain Metastases in Differentiated Thyroid Cancer: Clinical Presentation, Diagnosis, and Management

Background: Brain metastases (BM) are the most common intracranial neoplasms in adults and are a significant cause of morbidity and mortality. The brain is an unusual site for distant metastases of thyroid cancer; indeed, the most common sites are lungs and bones. In this narrative review, we discuss about the clinical characteristics, diagnosis, and treatment options for patients with BM from differentiated thyroid cancer (DTC). Summary: BM can be discovered before initial therapy due to symptoms, but in most patients, BM is diagnosed during follow-up because of imaging performed before starting tyrosine kinase inhibitors (TKI) or due to the onset of neurological symptoms. Older male patients with follicular thyroid cancer (FTC), poorly differentiated thyroid cancer (PDTC), and distant metastases may have an increased risk of developing BM. The gold standard for detection of BM is magnetic resonance imaging with contrast agent administration, which is superior to contrast-enhanced computed tomography. The treatment strategies for patients with BM from DTC remain controversial. Patients with poor performance status are candidates for palliative and supportive care. Neurosurgery is usually reserved for cases where symptoms persist despite medical treatment, especially in patients with favorable prognostic factors and larger lesions. It should also be considered for patients with a single BM in a surgically accessible location, particularly if the primary disease is controlled without other systemic metastases. Additionally, stereotactic radiosurgery (SRS) may be the preferred option for treating small lesions, especially those in inaccessible areas of the brain or when surgery is not advisable. Whole brain radiotherapy is less frequently used in treating these patients due to its potential side effects and the debated effectiveness. Therefore, it is typically reserved for cases involving multiple BM that are too large for SRS. TKIs are effective in patients with progressive radioiodine-refractory thyroid cancer and multiple metastases. Conclusions: Although routine screening for BM is not recommended, older male patients with FTC or PDTC and distant metastases may be at higher risk and should be carefully evaluated for BM. According to current data, patients who are suitable for neurosurgery seem to have the highest survival benefit, while SRS may be appropriate for selected patient.

Brain Metastases from Thyroid Carcinoma: Prognostic Factors and Outcomes

Intracranial metastases from thyroid cancer are rare. Although the prognosis of thyroid cancer patients is generally favorable, the prognosis of patients with intracranial metastases from thyroid cancer has been considered unfavorable owing to lower survival rates among such patients compared to those without intracranial involvement. Many questions about their management remain unclear. The aim of the present study was to analyze the characteristics, treatment modalities, and outcomes of patients with brain metastases from thyroid cancer. Among 4320 patients with thyroid cancer recorded in our institutional database over a 30-year period, the data of 20 patients with brain metastasis were retrospectively collected and analyzed. The clinical characteristics, histological type of primary cancer and metastatic brain tumor, additional previous distant metastasis, treatment modalities, locations and characteristics on radiologic findings, time interval between the first diagnosis of primary thyroid cancer and brain metastasis, and survival were analyzed. Among our patient cohort, the mean age at initial diagnosis was 59.3 ± 14.1 years, and at the manifestation of diagnosis of cerebral metastasis, the mean age was found to be 64.8 ± 14.9 years. The histological types of primary thyroid cancer were identified as papillary in ten patients, follicular in seven, and poorly differentiated carcinoma in three. The average interval between the diagnosis of thyroid cancer and brain metastasis was 63.4 ± 58.4 months (range: 0-180 months). Ten patients were identified as having a single intracranial lesion, and ten patients were found to have multiple lesions. Surgical resection was primarily performed in fifteen patients, and whole-brain radiotherapy, radiotherapy, or tyrosine kinase inhibitors were applied in the remaining five patients. The overall median survival time was 15 months after the diagnosis of BMs from TC (range: 1-252 months). Patients with thyroid cancer can develop brain metastasis even many years after the diagnosis of the primary tumor. The results of our study demonstrate increased overall survival in patients younger than 60 years of age at the time of diagnosis of brain metastasis. There was no difference in survival between patients with brain metastasis from papillary carcinoma and those with follicular thyroid carcinoma.

“Watch and wait” approach in the treatment of advanced radioiodine refractory differentiated thyroid cancer: a study of barriers and drivers of use

   Introduction. The multikinase inhibitors have demonstrated high clinical efficacy in treatment of the radioiodine refractory differentiated thyroid cancer. At the same time, the inclusion criteria in the studies has reflected a minimum set of characteristics important for beginning of use of these drugs and an approach that takes into account the tumor progression rate (the volume doubling time) in the absence of clinical manifestations of the disease that have made it possible to individualize the start of therapy.

   Aim. To describe and evaluate the barriers and drivers of use the “watch and wait” approach by Russian oncologists in treatment of the radioiodine refractory thyroid cancer.

   Materials and methods. We conducted 35 structured interviews with oncologists observing patients after radioiodine therapy in order to evaluate the “watch and wait” approach. unfortunately, data on use and prevalence of this approach in Russia are limited. The present study involved the use of deductive content analysis as well as analysis of implementation model of clinical guidelines and included investigation of issue of implementation of the “watch and wait” approach to current practice of therapy for radioiodine refractory differentiated thyroid cancer. One of the main tasks was to determine the influence of external factors on the treatment of this category of patients.

   Conclusion. Barriers and drivers of using “watch and wait” approach in the treatment of differentiated radioiodine refractory thyroid cancer are identified at several levels. for wide use of this approach, it is necessary to involve oncologists taking into account their attitude regarding changes in routine practices, patient expectations and to obtain additional data regarding its long-term effectiveness.

Survival Outcomes of Advanced Thyroid Cancer Enriched in Brain Metastases Following Treatment With Small Molecule Inhibitors

OBJECTIVE

Small molecule inhibitors (SMIs) are targeted therapies increasingly used in advanced thyroid carcinomas. This study aimed to evaluate the survival outcomes of thyroid cancer on SMI treatment, including in patients with brain metastases.

METHODS

This retrospective study included patients with thyroid carcinomas who received at least one SMI between 2008 and 2022 at a tertiary level, academic institution. SMI included lenvatinib, sorafenib, dabrafenib-trametinib, selpercatinib, and cabozantinib. Patients were grouped by the presence of brain metastasis. Kaplan-Meier and log-rank tests modeled the overall survival (OS), defined from detection of first metastasis.

RESULTS

In total, 116 patients (49.1% female, median age 61.1 years [IQR, 51.1-71.0]) were included. Thyroid cancer subtypes were: 57 (49.6%) papillary, 23 (19.8%) anaplastic, 23 (19.8%) medullary, and 13 (11.2%) follicular. There were 18 (15.5%) patients with brain metastases, and 98 (84.5%) with visceral metastases. Age, sex, thyroid subtype, SMI, and time to recurrence were not different between cohorts. OS was shorter in the brain metastasis cohort (31.7 vs 42.2 months, P =.44) and was not different after excluding anaplastic thyroid cancer (29.1 vs 62.3 months, P =.21). In the case of papillary thyroid cancer, patients with brain metastases trended toward worse OS (22.0 vs 59.9 months, P =.13). Nonanaplastic histology, total thyroidectomy (OR, 40.0; P <.001), number of unique therapies (OR, 10.9; P =.047), and mutation-directed therapy (OR, 24.7; P =.003) were associated with improved OS.

CONCLUSION

This single-institutional analysis reports survival outcomes of 116 patients with advanced thyroid cancer on targeted therapies, including 18 patients with brain metastases. Mutation-directed therapy for BRAFV600E mutations, RET mutations, RET fusions, and NTRK fusions had superior survival.

Clinical characteristics, treatment, and long-term outcome of patients with brain metastases from thyroid cancer

Brain metastases (BM) in patients with thyroid cancer (TC) are rare with an incidence of 1% for papillary and follicular, 3% for medullary and up to 10% for anaplastic TC (PTC, FTC, MTC and ATC). Little is known about the characteristics and management of BM from TC. Thus, we retrospectively analyzed patients with histologically verified TC and radiologically verified BM identified from the Vienna Brain Metastasis Registry. A total of 20/6074 patients included in the database since 1986 had BM from TC and 13/20 were female. Ten patients had FTC, 8 PTC, one MTC and one ATC. The median age at diagnosis of BM was 68 years. All but one had symptomatic BM and 13/20 patients had a singular BM. Synchronous BM at primary diagnosis were found in 6 patients, while the median time to BM diagnosis was 13 years for PTC (range 1.9-24), 4 years for FTC (range 2.1-41) and 22 years for the MTC patient. The overall survival from diagnosis of BM was 13 months for PTC (range 1.8-57), 26 months for FTC (range 3.9-188), 12 years for the MTC and 3 months for the ATC patient. In conclusion, development of BM from TC is exceedingly rare and the most common presentation is a symptomatic single lesion. While BM generally constitute a poor prognostic factor, individual patients experience long-term survival following local therapy.

Brain metastases of papillary thyroid carcinoma origin are derived from aggressive histologic variants and demonstrate similar adverse morphology in the metastatic lesion

BACKGROUND

Distant metastases of papillary thyroid carcinoma are exceedingly rare. We analyzed all cases of brain metastases of papillary thyroid cancer at our institution and performed a literature review over the past ten years to identify histologic and molecular features of primary and metastatic tumors.

METHODS

Following institutional review board approval, the entire pathology archives at our institution were searched for cases of papillary thyroid carcinoma metastatic to brain. Patient demographics, histologic features of both primary and metastatic tumors, molecular information, and clinical outcomes were investigated.

RESULTS

We identified 8 cases of metastatic papillary thyroid carcinoma to brain. The average age at time of diagnosis of metastases was 56.3 years (range: 30-85). Average time from diagnosis of primary thyroid cancer to brain metastasis was 9.3 years (range: 0-24 years). All primary thyroid carcinomas demonstrated aggressive sub-types which were correspondingly seen in brain metastases. Next-generation sequencing revealed the most common mutations were identified in BRAFV600E, NRAS, and AKT1 with one tumor harboring a TERT promoter mutation. Six out of eight patients were deceased at the time of study with an average survival time of 2.3 years (range: 0.17-7 years) following diagnosis of brain metastasis.

CONCLUSIONS

Based on our study, it is highly unlikely that a low-risk variant of papillary thyroid carcinoma will metastasize to the brain. Therefore, careful and accurate reporting of the papillary thyroid carcinoma subtype in primary thyroid tumors is warranted. Certain molecular signatures are associated with more aggressive behavior and worse patient outcomes and next-generation sequencing should be performed on metastatic lesions.

Possible association between minor head injury and intratumoral hemorrhage: A metastatic brain tumor from thyroid carcinoma

A 78-year-old woman presented after a fall and injury in the left forehead. She had undergone surgery for papillary thyroid carcinoma 14 years prior and breast carcinoma 7 years prior. The patient had exhibited uneventful postoperative courses without relapse or metastasis. Anticoagulants or antiplatelet agents were not prescribed her. At presentation, the patient exhibited no focal neurological deficits. Computed tomography revealed a 19 × 20 mm hemorrhagic lesion in the right temporal lobe. On cerebral magnetic resonance imaging, the center of the lesion exhibited inhomogeneous intensity on both T1- and T2-weighted sequences with heterogeneous enhancement. In contrast, the perilesional hemorrhagic regions, appearing hyperintense on both T1- and T2-weighted sequences, showed temporary regression followed by marked enlargement over the subsequent 123 days. The patient underwent total tumor resection. The microscopic findings of the resected specimens were consistent with papillary thyroid carcinoma. Minor head injuries may trigger intratumoral hemorrhage in metastatic brain tumors. Metastasis should be assumed when patients with a history of thyroid carcinoma present with a solitary parenchymal lesion with the appearance of cerebral cavernous malformation, even if they have been disease free for a long period.

Screening and treatment of brain metastasis from papillary thyroid carcinoma: a case series

BACKGROUND

The brain metastasis from differentiated thyroid carcinoma (DTC) is a rare condition and its prognosis is poor. The standard protocol for screening and treatment of patients with brain metastases from papillary thyroid cancer (PTC) remains controversial. This report aims to share the experience of a single center in the management of brain metastases from DTC.

MATERIAL AND METHODS

Five patients with brain metastases were identified from 5000 patients with DTC attending the department of nuclear medicine, Hospital 108 between 2016 to 2022. The statistical software Statistical Package for Social Sciences (SPSS) 20.0 (SPSS Inc., Chicago, IL, USA) was used to analyze the data.

RESULTS

Five patients with brain metastases from DTC were revealed by MRI, ¹⁸F-FDG PET/CT with contrast enhancement, and ¹³¹I-SPECT/CT. The median time of overall survival (OS) was 15 months, ranging from 10 to 65 months. Two out of the five patients underwent surgery, and futher 2 patients were treated with stereotactic surgery (SRS). All patients are still alive.

CONCLUSIONS

Brain metastases from DTC are rare. MRI is the preferred imaging mobility to screen brain lesions in DTC. The primary treatment modalities are surgery and SRS.

Rare sites of metastases in patients with differentiated thyroid carcinoma and added value of SPECT/CT over planar whole body radioactive iodine scan

Background

Being aware of the unusual or rare location of thyroid metastases helps in early diagnosis and proper patient management. Rare metastases (RM) can be missed resulting in diagnostic pitfalls and delayed treatment. The use of single-photon emission computed tomography/computed tomography (SPECT/CT) imaging in the follow-up of differentiated thyroid cancer (DTC) patients provides precise anatomical localization and characterization of RM that may be missed or misinterpreted in planar whole body iodine-131 (WBI) scan. There is a lack of knowledge about dealing with such patients, the treatment they should receive, and therapy response due to the rarity of such cases. In this work, we reported these rare cases increasing awareness about them and their methods of treatment with response to therapy and evaluated the added value of SPECT/CT imaging in changing patients’ management.

Materials and methods

In this study we reviewed all patients with DTC referred to our unit either for initial radioactive iodine-131 therapy (RAIT) or under follow-up from January 2019 to January 2022. When a suspected lesion was detected in a conventional planar WBI scan whether follow-up scan or post-therapeutic scan, SPECT/CT was acquired immediately in the same session for that region. Additional imaging modalities were performed for confirmation. Response to the given treatment either disease progression (DP) or favorable response which include complete response (CR), partial regression (PR) and stable disease (SD) recorded for each patient.

Results

Two hundred and forty patients with DTC referred to our unit over a three-year period (from January 2019 to January 2022) were reviewed. Forty patients developed lung and bone distant metastases. Twenty-one patients were thought to have metastases at unusual sites. Due to incomplete data (no SPECT/CT pictures or confirmatory imaging), 6/21 patients were eliminated. We studied 15 patients with RM (9 females, 6 males) with a median age of 52 years (range 27–79). All patients received the initial RAIT after thyroidectomy in addition to other therapeutic modalities, e.g., radiotherapy (RTH), chemotherapy (CTH) or surgical tumor excision after detection of RM. Ten out of 15 patients (66.67%) showed favorable response to therapy (2 patients had CR, 6 patients had PR and 2 patients had SD), whereas only 5 patients had DP. Additional SPECT/CT changed management in 10/15 patients (66, 67%) of patients.

Conclusion

RM identification is mandatory to avoid misdiagnosis and delayed therapy. Increasing the awareness about such rare cases allows for better management. SPECT/CT could significantly impact patients' management through its precise anatomic localization and lesion characterization.

Prognosis of Anaplastic Thyroid Cancer with Distant Metastasis

Anaplastic thyroid cancer (ATC) is derived from follicular thyroid cells and is associated with high mortality risk. Obtaining information to characterize ATC is difficult because ATC with distant metastasis is extremely rare. This study determined the clinical characteristics of ATC with distant metastasis. The medical records of 152 patients with ATC at Gangnam Severance Hospital were reviewed between January 2004 and March 2022. The primary endpoint was the overall survival of the total patient sample, patients with ATC and distant metastasis, and those with ATC and brain metastasis. Of the 152 patients with ATC, 88 had distant metastasis at diagnosis. The 5-year disease-specific survival was 24% for total ATC and 10% for ATC with distant metastasis. Survival for >1 year was 32% for total ATC and 15% for ATC with distant metastasis. The median survival rate differed significantly between the total ATC and ATC with distant metastasis groups (228.5 vs. 171 days). Among the ATC cases, 11% had brain metastasis; thus, brain MRI or CT is worth considering at diagnosis and follow-up, even if there were no statistical difference in overall survival between patients with ATC with and without brain metastasis.

Multimodal approach to the treatment of patients with radioiodine refractory differentiated thyroid cancer and metastases to the central nervous system

The diagnosis of central nervous system metastases in patients with radioiodine refractory differentiated thyroid cancer is a late and rare event that occurs in less than 1% of patients. Definitive conclusions on the overall clinical management cannot be drawn due to the limited number of patients included in retrospective series or post hoc analysis from clinical trials. However, most data show a trend to an increased benefit from a multimodal approach. Local treatment based on surgical and/or radiation techniques is highly encouraged for symptom control and to reduce tumor burden in this location despite a high risk of clinical complications. In addition, systemic treatment with novel tyrosine kinase inhibitors has demonstrated activity in this subgroup of patients, improving an otherwise unfavorable prognosis.

Prognostic factors to predict the efficacy of surgical interventions against brain metastasis secondary to thyroid cancer

Introduction

Brain metastasis in differentiated thyroid cancer (DTC) is rare (frequency < 1%) and has a poor prognosis. Treatment strategies for brain metastasis are not well established.

Objectives

We conducted a retrospective analysis to identify predictive factors for patient outcomes and verify surgical indications for patients with brain metastasis and DTC.

Methods

The study included 34 patients with pathologically confirmed DTC with brain metastasis from March 2008 to November 2020. The associations between overall survival (OS) and clinical factors were evaluated. Cox regression analysis was used to determine the relationship between clinical factors and OS. To assess the survival benefit of craniotomy, Kaplan-Meier survival analysis was performed for each variable whose statistical significance was determined by Cox regression analysis.

Results

The median OS of the entire patient sample was 11.4 months. Survival was affected by the presence of lung metastasis (P = 0.033) and the number of brain metastases (n > 3) (P = 0.039). Only the subgroup with the number of brain metastases ≤3 showed statistical significance in the subgroup analysis of survival benefit following craniotomy (P = 0.048).

Conclusions

The number of brain metastases and the existence of lung metastasis were regarded more essential than other clinical factors in patients with DTC in this study. Furthermore, craniotomies indicated a survival benefit only when the number of brain metastases was ≤3. This finding could be beneficial in determining surgical indications in thyroid cancer with brain metastasis.

Radiotherapy for Brain Metastases from Thyroid Cancer: An Institutional and National Retrospective Cohort Study

Background: Stereotactic radiosurgery (SRS) is the standard of care for patients with a limited number of brain metastases. Despite the fact that the seminal studies regarding SRS for brain metastases were largely tissue agnostic, several current national guidelines do not uniformly recommend SRS in thyroid cancer. We therefore investigated oncological outcomes in a cohort of patients with brain metastases from thyroid cancer who received radiotherapy (RT) at our institution as well as those in a nationally representative cancer cohort, the National Cancer Database (NCDB). Materials and Methods: We identified patients with thyroid cancer and brain metastases treated with RT at our institution from 2002 through 2020. For the NCDB cohort, the national database of patients with thyroid cancer was screened on the basis of brain-directed RT or brain metastases. For the institutional cohort, the cumulative risk of local failure (LF), distant intracranial failure, and radiation necrosis were calculated, adjusted for the competing risk of death. Overall survival (OS) in both cohorts was analyzed using the Kaplan-Meier method. Univariate analysis was accomplished via clustered competing risks regression. Results: For the institutional cohort, we identified 33 patients with 212 treated brain metastases. OS was 6.6 months. The 1-year cumulative incidences of LF and distant intracranial failures were 7.0% and 38%, respectively. The 1-year risk of radiation necrosis was 3.3%. In the NCDB cohort, there were 289 patients, and the median survival was 10.2 months. NCDB national practice patterns analysis showed an increasing use of SRS over time in both the entire cohort and the subset of anaplastic patients. Univariate analysis was performed for OS, risk of LF, risk of regional intracranial failure, and risk of radiation necrosis. Conclusions: SRS is a safe, effective, and increasingly utilized treatment for thyroid cancer brain metastases of any histology and should be the standard of care treatment.

Metastatic brain lesion as the initial presentation of follicular thyroid carcinoma

Background:

Metastatic brain lesions, of thyroid origin, are rare manifestations of differentiated thyroid cancer, with papillary thyroid carcinoma being the most common subtype. Considering the rarity of metastatic follicular thyroid carcinoma to the brain, the present article outlines its clinical presentation, neuroradiological findings, pathological features, and outcome.

Case Description:

A 52-year-old female presented with a 6-month history of progressive and holocephalic headache. Examination revealed a tracheal deviation to the left side due to an enlarged goiter. Brain CT scan showed a right occipital, slightly hyperdense lesion associated with a 0.4 cm midline shift to the left side. Brain MRI demonstrated a right occipital, avidly-enhancing, extra-axial lesion with disproportionate and extensive vasogenic edema. As the lesion was solitary, the patient underwent craniotomy and tumor resection. Histopathological examination revealed a tumor consistent of small follicles, composed of uniform round nuclei without papillary thyroid carcinoma nuclear features, suggestive of metastatic follicular thyroid carcinoma to the brain. Postoperatively, the patient was neurologically intact. She was discharged in a stable condition with laboratory/ radiological investigations and follow-up at neurosurgery, endocrine, radiotherapy, and thyroid surgery clinics.

Conclusion:

Follicular thyroid carcinoma may rarely metastasize to the central nervous system. A high index of suspicion is required to identify patients with thyroid cancer who initially present with neurological manifestations. Complete surgical resection of the metastatic brain lesion is safe, feasible and is associated with a prolonged overall survival.

Rationale for therapeutic decision-making in locally advanced and metastatic radioactive iodine (RAI)-refractory differentiated thyroid cancer, starting from a clinical case

Iodine uptake and organification are the hallmarks of thyroid cells differentiation. The loss of these characteristics in thyroid cancer leads to radioactive iodine refractoriness, a rare condition that bears a low survival rate and poor prognosis. We present a 52-year-old patient presenting dry cough and dyspnea in the supine position. Imaging examinations revealed a thyroid nodule with a high suspicion of malignancy in the right thyroid lobe, multiple laterocervical and mediastinal lymph nodes, lung, bone, and brain metastases. Fine needle aspiration cytologic features have advocated for papillary thyroid cancer (PTC). The patient underwent total thyroidectomy and selective lymphadenectomy. Subsequently, the patient received suppressive treatment with levothyroxine and four courses of radioactive iodine therapy. In addition, to treat bone and brain metastases, the patient experienced external radiotherapy and glucocorticoid therapy. Despite this rigorous therapeutic management, the patient obtained an incomplete structural and functional response. Although the last two posttherapeutic ¹³¹I whole-body scans were negative, the patient had elevated stimulated thyroglobulin levels and loco-regional recurrence by thyroid ultrasound. This aspect would suggest that thyroid cells become unable to uptake ¹³¹I, most likely through the emergence of new genetic mutations in the cancer cells. In conclusion, our patient’s case suggests a ¹³¹I-refractory PTC, requiring the initiation of novel targeted systemic agents such as tyrosine kinase inhibitors, in order to improve structural and functional outcomes of radioactive iodine therapy and to afford prolonged progression-free survival advantage.

Clinico-radiological features of brain metastases from thyroid cancer

The brain is an unusual site for distant metastases of thyroid cancer. The radiological features of brain metastases (BMs) have rarely been reported. Hemorrhage is frequently noted in BMs from thyroid cancer. This study aimed to investigate the clinico-radiological features of BMs from thyroid cancer and to determine the risk factors to predict BM hemorrhage.We retrospectively evaluated the MR images of 35 patients with BMs from thyroid cancer at our hospital from 2013 to 2020. The number, size, site, presence of extra-cranial metastasis, presence of perilesional edema, intra-tumoral hemorrhage, enhancement pattern, and presence of diffusion restriction on MRI were described. We further classified the thyroid cancers into hemorrhagic and nonhemorrhagic groups to investigate the factors associated with hemorrhage.54.29% of patients with thyroid BMs (19/35) had neurologic symptoms. 94.29% of patients (33/35) had extra-cranial metastases. The most common histology of primary thyroid cancer was papillary thyroid cancer (71.43%, 25/35), followed by anaplastic thyroid cancer (22.86%, 8/35). Thyroid cancer BMs were located mostly in the supra-tentorium (51.43%, 18/35) or both the supra and infra-tentorium (45.71%, 16/35). 60% of patients (21/35) showed hemorrhage within the BMs. The strongest predictor for BM hemorrhage was tumor size (variable importance: 50).Thyroid cancer BMs exhibit a bleeding tendency. Furthermore, larger BMs are more likely to have an intra-tumoral hemorrhage.

Development and validation of a prediction model based on the organ-based metabolic tumor volume on FDG-PET in patients with differentiated thyroid carcinoma

BACKGROUND

Although patients with differentiated thyroid cancer (DTC) generally have a good prognosis, patients with a large metabolic tumor volume (MTV) on FDG-PET may experience poor clinical courses. We measured organ-based MTVs and tested its prognostic performance in comparison to conventional MTV (cMTV).

METHODS

We retrospectively analyzed the cases of 280 patients who received their first I-131 therapy in 2003-2014 at our hospital and showed an FDG-avid metastatic lesion. We randomly divided the patients into training (n = 190) and validation (n = 90) datasets. We classified the MTVs as MTVneck-node, MTVdistant-node, MTVlung, MTVbone, and MTVother-organs and tested with/without dichotomization vis-à-vis overall survival (OS). Based on the estimated weighting coefficients of the organ-based MTVs, we propose a new index: the adjusted whole-body MTV (aMTV). Using the validation dataset, we compared the aMTV with cMTV for predicting OS.

RESULTS

In a univariate analysis, MTVdistant-node and MTVother-organs were more strongly correlated with the OS than the dichotomized forms, whereas the dichotomized forms of MTVneck-node, MTVlung, and MTVbone were more strongly correlated with OS than the continuous variables. The aMTV was thus expressed as 0.69 × dic(MTVneck-node) + 0.02 × MTVdistant-node + 1.05 × dic(MTVlung) + 1.58 × dic(MTVbone) + 0.01 × MTVother-organs, where dic(x) represents 0 or 1 based on the optimized cut-off. In the model evaluation using the validation group, aMTV was a significant predictor of OS with a higher c-index (0.7676) than cMTV (0.7218).

CONCLUSION

In DTC patients with FDG-avid metastasis before I-131 therapy, all organ-based MTVs were significant predictors of prognosis. As the aMTV outperformed the cMTV for predicting prognoses, we recommend measuring the MTV on an organ basis.

Stereotactic Radiosurgery for Differentiated Thyroid Cancer Brain Metastases: An International, Multicenter Study

Background: Brain metastases (BM) from differentiated thyroid cancer are rare. Stereotactic radiosurgery (SRS) is commonly used for the treatment of BMs; however, the experience with SRS for thyroid cancer BMs remains limited. The goal of this international, multi-centered study was to evaluate the efficacy and safety of SRS for thyroid cancer BMs. Methods: From 10 institutions participating in the International Radiosurgery Research Foundation, we pooled patients with established papillary or follicular thyroid cancer diagnosis who underwent SRS for histologically confirmed or radiologically suspected BMs. We investigated patient overall survival (OS), local tumor control, and adverse radiation events (AREs). Results: We studied 42 (52% men) patients who underwent SRS for 122 papillary (83%) or follicular (17%) thyroid cancer BMs. The mean age at SRS was 59.86 ± 12.69 years. The mean latency from thyroid cancer diagnosis to SRS for BMs was 89.05 ± 105.49 months. The median number of BMs per patient was 2 (range: 1-10 BMs). The median SRS treatment volume was 0.79 cm³ (range: 0.003-38.18 cm³), and the median SRS prescription dose was 20 Gy (range: 8-24 Gy). The median survival after SRS for BMs was 14 months (range: 3-58 months). The OS was significantly shorter in patients harboring ≥2 BMs, when compared with patients with one BM (Log-rank = 5.452, p = 0.02). Two or more BMs (odds ratio [OR] = 3.688; confidence interval [CI]: 1.143-11.904; p = 0.03) and lower Karnofsky performance score at the time of SRS (OR = 0.807; CI: 0.689-0.945; p = 0.008) were associated with shorter OS. During post-SRS imaging follow-up of 25.21 ± 30.49 months, local failure (progression and/or radiation necrosis) of BMs treated with SRS was documented in five (4%) BMs at 7.2 ± 7.3 months after the SRS. At the last imaging follow-up, the majority of patients with available imaging data had stable intracranial disease (33%) or achieved complete (26%) or partial (24%) response. There were no clinical AREs. Post-SRS peritumoral T2/fluid attenuated inversion recovery signal hyperintensity was noted in 7% BMs. Conclusion: The SRS allows durable local control of papillary and follicular thyroid cancer BMs in the vast majority of patients. Higher number of BMs and worse functional status at the time of SRS are associated with shorter OS in patients with thyroid cancer BMs. The SRS is safe and is associated with a low risk of AREs.

Clinical Indications for Treatment with Multi-Kinase Inhibitors in Patients with Radioiodine-Refractory Differentiated Thyroid Cancer

Differentiated thyroid cancer is usually a slow-growing disease, even if the patients develop distant metastasis. For recurrent or metastatic disease, radioactive iodine therapy is a standard treatment. However, the disease gradually progresses in some of the patients and can ultimately develop into life-threatening conditions. For patients with progressive radioactive iodine-refractory differentiated thyroid cancer (RR-DTC), multi-kinase inhibitors (MKIs) including sorafenib and lenvatinib prolonged progression-free survival compared with placebo in pivotal randomized phase 3 trials, although the benefit in overall survival has not been clearly confirmed, possibly because the patients who received placebo were permitted to cross-over to lenvatinib upon disease progression. Moreover, the adverse events related to MKIs were not negligible. Therefore, the optimal timing of MKI initiation has long been controversial, and physicians should consider various patient and disease factors. Herein, we comprehensively review the clinical factors that can be helpful in determining the initiation of MKIs for patients with RR-DTC.

Site-Specific Metastasis and Survival in Papillary Thyroid Cancer: The Importance of Brain and Multi-Organ Disease

Introduction-heterogeneity in clinical outcomes and survival was observed in patients with papillary thyroid cancer (PTC) and distant metastases. Here, we investigated the effect of distant metastases sites on survival in PTC patients. Methods-patients with a diagnosis of PTC and known metastases were identified using the Surveillance, Epidemiology, and End Results database (1975-2016). Univariate and multivariate Cox regression analyses were performed to analyze the effect of distant metastases sites on thyroid cancer-specific survival (TCSS) and overall survival (OS). Results-from 89,694 PTC patients, 1819 (2%) developed distant metastasis at the initial diagnosis, of whom 26.3% presented with the multiple-organ disease. The most common metastatic sites were lung (53.4%), followed by bone (28.1%), liver (8.3%), and brain (4.7%). In metastatic patients, thyroid cancer-specific death accounted for 73.2%. Kaplan-Meier curves showed decreased OS in patients with metastases to the brain (median OS = 5 months) and liver (median OS = 6 months) compared to lung (median OS = 10 months) and bone (median OS = 23 months). Moreover, multiple organ metastasis had a higher mortality rate (67.4%) compared to single organ metastasis (51.2%, p < 0.001). Using multivariate analysis, risk factors that significantly influence TCSS and OS were male gender (HR = 1.86, 95% CI = 1.17-2.94, p < 0.001, and HR = 1.90, 95% CI = 1.40-2.57, p = 0.009), higher tumor grade (HR = 7.31, 95% CI = 2.13-25.0, p < 0.001 and HR = 4.76, 95% CI = 3.93-5.76, p < 0.001), multiple organ involvement (HR = 6.52, 95% CI = 1.50-28.39, p = 0.026 and HR = 5.08, 95% CI = 1.21-21.30, p = 0.013), and brain metastasis (HR = 1.82, 95% CI = 1.15-2.89, p < 0.001 and HR = 4.21, 95% CI = 2.20-8.07, p = 0.010). Conclusion-the pattern of distant metastatic organ involvement was associated with variability in OS in PTC. Multi-organ metastasis and brain involvement are associated with lower survival rates in PTC. Knowledge of the patterns of distant metastasis is crucial to personalize the treatment and follow-up strategies.

Brain Metastases From Differentiated Thyroid Carcinoma: A Retrospective Study of 22 Patients

BACKGROUND

Brain metastasis from differentiated thyroid cancer has followed a similar increasing trend to that of thyroid cancer in recent years. However, the characteristics and treatments for brain metastases are unclear. The aim of this study was to understand this disease by analyzing patients with brain metastases from differentiated thyroid cancer (DTC).

METHODS

Between 2000 and 2020, the database of the Sun Yat-sen University Cancer Center was searched for differentiated thyroid cancer patients. We identified a cohort of 22 patients with brain metastases. The characteristics of the patients, histological features, treatments, and time of death were reviewed. The overall survival (OS) rate was calculated using the Kaplan Meier method. Survival curves of different subgroups were compared according to baseline characteristics and treatments received.

RESULTS

A total of 22 (1.09%) out of 2013 DTC patients in the Sun Yat-sen University Cancer Center database were identified as having brain metastases. The overall median survival time was 17.5 months (range from 1-60 months) after diagnosis of brain metastasis. Performance statue (PS), tumor site, and neurosurgery impacted survival, according to Kaplan-Meier analysis. Prognosis of skull metastasis was superior to that of intracranial types. Neurosurgery was the only type of treatment that had an impact on patient OS.

CONCLUSIONS

Brain metastasis from differentiated thyroid cancer has a poor prognosis. However, it can be improved by comprehensive treatment. PS of the patients can greatly affect survival. Skull metastases have improved prognosis over intracranial types. Radioiodine therapy (RAIT) appears to effectively improve the prognosis of patients with skull metastases from DTC.

Brain metastases assessment by FDG-PET/CT: can it eliminate the necessity for dedicated brain imaging?

Background

Brain metastases (BM) are the most common intracranial tumors in adults outnumbering all other intracranial neoplasms. Positron emission tomography combined with computed tomography (PET/CT) is a widely used imaging modality in oncology with a unique combination of cross-sectional anatomic information provided by CT and the metabolic information provided by PET using the [18F]-2-fluoro-2-deoxy-d-glucose (FDG) as a tracer. The aim of the study is to assess the role and diagnostic performance of brain-included whole-body PET/CT in detection and evaluation of BM and when further imaging is considered necessary. The study was conducted over a period of 12 months on 420 patients suffering from extra-cranial malignancies utilizing brain-included whole-body PET/CT.

Results

Thirty patients with 71 brain lesions were detected, 18 patients (60%) had BM of unknown origin while 12 patients (40%) presented with known primary tumors. After brain-included whole-body FDG-PET/CT examination, the unknown primaries turned out to be bronchogenic carcinoma in 10 patients (33.3%), renal cell carcinoma in 2 patients (6.7%), and lymphoma in 2 patients (6.7%), yet the primary tumors remained unknown in 4 patients (13.3%). In 61 lesions (85.9%), the max SUV ranged from 0.2- < 10, while in 10 lesions (14.1%) the max SUV ranged from 10 to 20. Hypometabolic lesions were reported in 41 (57.7%) lesions, hypermetabolic in 3 lesions (4.2%), whereas 27 lesions (38.0%) showed similar FDG uptake to the corresponding contralateral brain matter. PET/CT overall sensitivity, specificity, positive and negative predictive, and accuracy values were 78.1, 92.6, 83.3, 90, and 88% respectively.

Conclusion

Brain-included whole-body FDG-PET/CT provides valuable complementary information in the evaluation of patients with suspected BM. However, the diagnostic performance of brain PET-CT carries the possibility of false-negative results with consequent false sense of security. The clinicians should learn about the possible pitfalls of PET/CT interpretation to direct patients with persistent neurological symptoms or high suspicion for BM for further dedicated CNS imaging.

Unusual metastases from differentiated thyroid carcinoma: analysis of 36 cases

PURPOSE

Metastases of differentiated thyroid cancer (DTC) in sites different from lungs and bone are unusual (UM); their impact in management and prognosis remains unknown. Our aim was to evaluate the prevalence of UM, to describe their characteristics and to analyze their impact in disease outcome and mortality.

METHODS

We retrospectively reviewed the file records from 8 different centers. Those patients with DTC and UM were included. UM were diagnosed by: (i) biopsy/cytology and/or (ii) radioiodine (RAI) uptake associated to elevated thyroglobulin (Tg) levels and/or c) presence of one or more structural lesion/s with 18-FDG uptake in the PET/CT scan and elevated Tg levels.

RESULTS

Thirty-six (0.9%) out of a total of 3982 DTC patients were diagnosed with UM; 75% had papillary histology. The most frequent localization was central nervous system (CNS, 31%). UM were metachronous in 75%, symptomatic in 55.6% and fulfilled RAI-refractoriness criteria in 77.8% of cases. Metastatic lesions in lung/bone and/or locoregional disease were present in 34 cases (94.4%). Diagnosis of UM changed the therapeutic approach in 72.2% of patients. After a median follow up of 13 months, 21 (58.3%) patients died from DTC related causes. In 8 of them CNS progression was the immediate cause of death.

CONCLUSIONS

Prevalence of UM was low; they were frequently metachronic and RAI-refractory. Although UM were found in patients with widespread disease, their diagnosis usually led to changes in therapy. UM were associated with poor prognosis and high frequency of disease-specific mortality.

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

PURPOSE

Brain metastases (BMs) in patients with differentiated thyroid cancer (DTC) are rare but associated with poor prognosis. We examined risk factors for overall survival (OS) in this population and explored the pattern of genomic alterations.

METHODS

Single-institution, retrospective review of all patients with DTC from January 2000 to November 2016 identified 79 patients for analysis. Multiple prognostic factors, including age, gender, distal metastasis (DM), diagnosis time, DM sites, BM diagnosis time, BM number and size, genomic sequencing data, craniectomy, external beam radiation therapy, and kinase inhibitor therapies, were evaluated. Univariate and multivariate analyses were performed.

RESULTS

Median survival after BM was 18 months. One- and 3-year survival rates were 63% and 33%, respectively. Univariate analysis identified 4 covariates correlated with prolonged survival: time between DTC diagnosis and BM for less than 3 years (P = 0.01), time from initial DM diagnosis to BM for 22 months or less (P = 0.03), 3 BM sites or fewer (P = 0.002), and craniectomy (P = 0.05). Multivariate model revealed 3 variables associated with OS: DTC diagnosis to BM time of less than 3 years (P = 0.04), craniectomy (P = 0.06), and patients with fewer than 3 BM sites (P = 0.06). The majority of patients with BM had a telomerase reverse transcriptase promoter mutation, However, mutational status was not an independent predictor of survival.

CONCLUSIONS

For BM from DTC, time interval between DTC diagnosis and BM, number of BM sites, and craniectomy were independently associated with OS. Further studies are needed to define the role of genomic mutations in advanced cancer.

Local ablative therapy of oligoprogressive TKI-treated thyroid cancer

Metastatic cancer patients generally respond well to treatment with tyrosine kinase inhibitors (TKIs). However, TKI resistance occurs in almost all cases and often leads to a change in treatment. Recent guidelines, including thyroid cancer, raised the possibility of locally treating TKI-resistant oligoprogressive disease, i.e., one or a few progressing lesions in an otherwise treatment-responsive metastatic cancer, thereby obviating the need to change the ongoing TKI. To determine the benefits of this intervention, we reviewed studies on the use of LAT for TKI-treated oligoprogressive cancers. We found that in non-small cell lung cancer at least, LAT prolongs disease control and the duration of exposure to a TKI irrespective of the LAT used. Moreover, we reviewed the local ablative therapies (LATs) that are feasible for the local control of oligoprogressive thyroid cancer. Lastly, we report two illustrative cases of patients with oligoprogressive thyroid cancer treated with two different LATs while on therapy with TKIs. Both LATs extended the duration of disease control and the time of exposure to the ongoing TKI, thereby indicating that LAT is a favorable option for TKI-treated oligoprogressive thyroid cancer. Prospective randomized studies are needed to verify the benefit of LATs in terms of progression-free and overall survival in this increasingly frequent clinical setting.

INTRAMEDULLARY SPINAL CORD METASTASIS AS THE PRESENTING FEATURE OF PAPILLARY THYROID CARCINOMA

Objective

The objective of this report is to present an unusual case of intramedullary spinal cord metastasis (ISCM) as the presenting feature of papillary thyroid carcinoma (PTC).

Methods

The presented case includes clinical, biochemical, and imaging findings as well as surgical and pathology reports. Treatment with radioactive iodine (RAI) and the response to this treatment are presented.

Results

A 71-year-old woman was evaluated for debilitating low back pain and walking disability. Magnetic resonance imaging demonstrated an oval, lumbar, intramedullary mass with benign features and surgery was scheduled. On preoperative evaluation for the lumbar mass, a multinodular thyroid goiter (unfortunately overlooked previously) was noticed, causing severe narrowing of the trachea. Total thyroidectomy was performed with a pathology diagnosis of PTC. In a second operation, the lumbar lesion was removed and proved to represent metastatic PTC. External beam radiation was subsequently administered to the thyroid bed, lumbar spine, and other skeletal metastases, followed by 150 milliCurie of RAI. A post-treatment scan showed high uptake over the lumbar spine, and skeletal and lung lesions. Clinically, the patient restored her walking ability and back pain improved.

Conclusion

ISCM rarely is the presenting feature of PTC. Our patient presented with back pain which is the typical, though non-specific symptom, of ISCM. She showed good clinical response to multimodal treatment which is in line with the few other differentiated thyroid cancer patients with ISCM reported in the literature. Prompt surgical resection, followed by external beam radiation and RAI, may improve neurological signs, alleviate pain, and improve quality of life.

Brain Metastases From Differentiated Thyroid Carcinoma: Prevalence, Current Therapies, and Outcomes

BACKGROUND AND OBJECTIVE

The brain is an unusual site for distant metastases of differentiated thyroid carcinoma (DTC). The aim of this study was to document the prevalence of brain metastases from DTC at our institutions and to analyze the current therapies and the outcomes of these patients.

METHODS

We performed a retrospective chart review of patients with DTC and secondary neoplasia of the brain.

RESULTS

From 2002 to 2016, 9514 cases of thyroid cancer were evaluated across our institutions and 24 patients met our inclusion criteria, corresponding to a prevalence of 0.3% of patients with DTC. Fourteen (58.3%) were female and 10 (41.7%) were male. Fifteen patients had papillary thyroid cancer (PTC) (62.5%). Brain metastases were diagnosed 0 to 37 years (mean ± SD, 10.6 ± 10.4 years) after the initial diagnosis of thyroid cancer. Patients undergoing surgery had a median survival time longer than those that did not undergo surgery (27.3 months vs 6.8 months; P = 0.15). Patients who underwent stereotactic radiosurgery (SRS) had a median survival time longer than those that did not receive SRS (52.5 months vs 6.7 months; P = 0.11). Twelve patients (50%) were treated with tyrosine kinase inhibitors (TKIs), and they had a better survival than those who have not used a TKI (median survival time, 27.2 months vs 4.7 months; P < 0.05).

CONCLUSION

The prevalence of brain metastases of DTC in our institutions was 0.3% over 15 years. The median survival time after diagnosis of brain metastases was 19 months. In our study population, the use of TKI improved the survival rates.

Outcomes and prognostic factors in thyroid cancer patients with cranial metastases: A retrospective cohort study of 4,683 patients

BACKGROUND

Cranial metastasis of thyroid cancer is rare. The aim of this study was to analyse the clinical characteristics, treatments and outcomes of thyroid cancer patients with cranial metastasis and to identify the associated prognostic factors.

MATERIALS AND METHODS

Between January 1977 and August 2017, a total of 4683 patients were histologically confirmed to have thyroid cancer. Among them, 25 patients (0.53%) were identified as having cranial metastases, and their medical records were reviewed. The Kaplan-Meier method with a log-rank test was performed with cancer-specific survival as the main outcome. Cox regression analysis was used to examine the potential prognostic factors influencing patient survival.

RESULTS

Of the 25 patients, 21 were female, and 4 were male. The median age at the time of diagnosis of cranial metastasis was 63 years. Sixteen patients had metastases to the brain, and nine patients had metastases involving the skull only. Papillary carcinoma and follicular carcinoma accounted for 84.0% of cases. Twenty-four cases (96.0%) had extracranial metastases at the time of diagnosis of cranial metastases. Twenty patients received surgery, and 4 patients received palliative radiotherapy. One patient received supportive care only. The median cancer-specific survival after the diagnosis of cranial metastases was 27 months. According to the Kaplan-Meier test, 3 factors had a significant impact on survival, the metastatic site, histological types and surgical resection. According to the Cox regression analysis, skull metastases (HR: 0.274, 95% CI: 0.083-0.904, p = 0.033) and surgical resection (HR: 0.134, 95% CI: 0.019-0.929, p = 0.042) were identified as independent prognostic factors for a better outcome.

CONCLUSIONS

Surgical resection is the mainstay therapy for thyroid cancer patients with cranial metastasis. Cranial metastases involving the skull only are associated with a better outcome.

Pediatric Patient With Cerebral Metastasis From Papillary Thyroid Cancer

Brain metastasis from papillary thyroid carcinoma is uncommon. Concurrent cerebral and pulmonary metastases from papillary thyroid carcinoma is rare, especially in pediatric patients. We report a case of a brain metastasis revealed on post-therapy I scan in a 12 year old girl with thyroid cancer who also had diffuse pulmonary metastases which were partially responsive to sequential I therapy.

Clinical characteristics and disease outcome of patients with non-medullary thyroid cancer and brain metastases

Brain metastases from non-medullary thyroid carcinoma (NMTC) are rare, with a reported frequency of ~1%, and patient survival time is <1 year after diagnosis. The optimal management of brain metastases in this setting continues to be debated. The aim of the present study was to evaluate a series of patients with brain metastases from NMTC attending a single tertiary medical center. The electronic database of Rabin Medical Center was reviewed for all patients with NMTC and distant metastases who were diagnosed and treated between 1970 and 2014. Those with brain metastases were identified and formed the study group. Data were collected from medical records comprising clinicopathological characteristics, time intervals for diagnosis and treatment, treatment modalities and outcome. Of the 172 patients with NMTC and distant metastases, 10 possessed brain metastases. These included 6 females and 4 males of median age 53.5 years (range, 18–81 years). All patients had lung metastases and 7 demonstrated bone metastases. The median interval between the diagnoses of NMTC and brain metastases was 40 months (range, 9–207 months). Of the 10 patients, 1 presented with brain metastases at primary diagnosis. Treatment of the brain metastases consisted of surgery, radiotherapy (external beam, stereotactic), and radioiodine, alone or in combination. A total of 2 patients received tyrosine kinase inhibitors. The median overall survival time from diagnosis of brain metastasis was 15 months. A total of 2 patients remained alive at the last follow-up (32 and 300 months, respectively). The present study demonstrated that brain metastases may occur in ≤6% of patients with NMTC and distant metastases. Brain metastases rarely present at diagnosis of NMTC and are associated with metastases in other distant sites. Systematic screening for brain metastases requires consideration in all patients with NMTC and distant metastases. Some patients show an indolent evolution with overall survival of >2 years, supporting an aggressive treatment approach.

Management of Solitary Intracranial Metastases of Differentiated Thyroid Carcinoma: 11 Pathologically Confirmed Cases and Systematic Literature Review

BACKGROUND

Solitary intracranial metastases of differentiated thyroid carcinoma (DTC) are rare, and their management is still controversial. This research aimed to seek suitable therapeutic methods for this disease.

METHODS

We retrospectively studied 11 pathologically confirmed cases of solitary intracranial metastases of DTC in a single institution from January 2000 to December 2016 and systematically reviewed 52 cases of this disease out of 416 cases described in the literature on PubMed. These 63 cases were analyzed by Kaplan-Meier analysis, Cox regression analysis, and post-hoc test.

RESULTS

The diameters of intracranial metastases in all 63 cases were greater than 2 cm. Lung metastases (P = 0.000) and neurosurgery (P = 0.014) were 2 independent prognostic factors of this disease. Only neurosurgery (P = 0.05) was an independent prognostic factor in the patients with lung metastases, and neurosurgery (P = 0.044) and whole brain radiotherapy (WBRT) (P = 0.041) were 2 independent factors in the patients without lung metastases. Longer overall survival (OS) was achieved in the gross total removal (GTR) and subtotal removal (STR) groups than in the no neurosurgery group (P = 0.015, P = 0.084, respectively), and there was no significance between the GTR and STR groups (P = 0.918).

CONCLUSION

The patients without lung metastases had a better prognosis than did the patients with lung metastases. Neurosurgery could obviously improve the prognosis, and if possible, GTR of metastases was supposed to be achieved; STR could be considered. WBRT was a suitable method after neurosurgery in the patients without lung metastases but could not prolong OS in the patients with lung metastases.

Novel concepts for initiating multitargeted kinase inhibitors in radioactive iodine refractory differentiated thyroid cancer

Multitargeted kinase inhibitors have been shown to improve progression-free survival in patients with structurally progressive, radioactive iodine refractory differentiated thyroid cancer. While the inclusion criteria for phase 3 clinical trials and clinical practice guidelines provide guidance with regard to the minimal requirements that need to be met prior to initiation of a multitargeted kinase inhibitor, a better way to integrate the rate of structural disease progression with the size of the metastatic foci to more precisely define the optimal time to recommend initiation of therapy for individual patients is needed. In this manuscript we describe how to use assessments of tumor size and growth rates (structural disease doubling times) to define the critical point in time when the volume and rate of progression of metastatic structural disease merits consideration for initiation of systemic therapy (the inflection point).

Long-term follow-up of papillary and follicular thyroid carcinomas with bone metastasis

The aims of this study were to investigate papillary and follicular thyroid carcinomas with bone metastasis in various clinical presentations and to determine the prognostic factors after multimodality treatment. A retrospective analysis was performed of 3,120 patients with papillary and follicular thyroid carcinoma. Of these patients, 131 (including 97 women, 71.8%) were diagnosed with bone metastasis and underwent follow-up at the Chang Gung Medical Center. Patients with bone metastasis were categorized into two groups. Group A was comprised of patients who were diagnosed with bone metastasis either before thyroidectomy or within 6 months of the initial thyroidectomy (90 patients, 68.7%). Group B was comprised of patients with bone metastasis who received a diagnosis 6 months post-thyroidectomy in the follow-up period (41 patients, 31.3%). After a mean follow-up period of 8.4 ± 7.0 years, there were 88 deaths (67.2%) attributed to thyroid cancer and 13 patients (9.9%) achieved disease-free status. A multivariate analysis showed that older age, early diagnosis, and brain metastasis were each associated with a poor prognosis. The difference in disease-specific mortality rates between groups A and B was significant (p < 0.0001). In conclusion, papillary and follicular thyroid cancers with bone metastasis have a high rate of mortality. Despite this high mortality, 9.9% patients still had an excellent response to treatment.

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.

Hürthle cell carcinoma: current perspectives

Hürthle cell carcinoma (HCC) can present either as a minimally invasive or as a widely invasive tumor. HCC generally has a more aggressive clinical behavior compared with the other differentiated thyroid cancers, and it is associated with a higher rate of distant metastases. Minimally invasive HCC demonstrates much less aggressive behavior; lesions <4 cm can be treated with thyroid lobectomy alone, and without radioactive iodine (RAI). HCC has been observed to be less iodine-avid compared with other differentiated thyroid cancers; however, recent data have demonstrated improved survival with RAI use in patients with HCC >2 cm and those with nodal and distant metastases. Patients with localized iodine-resistant disease who are not candidates for a wait-and-watch approach can be treated with localized therapies. Systemic therapy is reserved for patients with progressive, widely metastatic HCC.

Clinical outcomes of a cohort of patients with central nervous system metastases from thyroid cancer

INTRODUCTION

Metastases to central nervous system (M₁-CNS) are rarely reported in thyroid cancer (TC) patients. We aimed to characterize patients with M₁-CNS from TC followed in our department.

METHODS

Review of the medical records of 27 patients with TC-related M₁-CNS.

RESULTS

Mean age at TC diagnosis was 56.9 ± 19.1 years. Papillary TC (55.6%) was the commonest histological type, followed by poorly differentiated (18.5%), medullary (11.1%), follicular (7.4%) and Hürthle cell (7.4%) carcinomas. Angioinvasion and extrathyroidal extension were observed in a high number of patients. At M₁-CNS diagnosis, other distant metastases were already present in 77.8% of the patients. Treatment directed to M₁-CNS was offered to 20 (74%) patients: 1 was submitted to surgery, 18 to radiotherapy (either whole-brain radiotherapy or stereotaxic radiosurgery or both) and 4 to surgery and radiotherapy. Four patients received cytotoxic chemotherapy and one was submitted to ¹³¹I. Median survival since M₁-CNS detection was 5.0 months. The only factor associated with better survival was surgery to brain metastases (P = 0.012).

CONCLUSIONS

The management of these patients is very challenging given the inexistence of effective treatments, except for brain surgery in selected cases.

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.

The Largest Known Survival Analysis of Patients with Brain Metastasis from Thyroid Cancer Based on Prognostic Groups

PURPOSE

To analyze the clinical features and prognostic factors associated with the survival of patients with a very rare occurrence of brain metastasis (BM) from differentiated thyroid cancer (DTC).

METHODS AND MATERIALS

A total of 37 patients with DTC who were diagnosed with BM between 1995 and 2014 were included. We reviewed the clinical characteristics, treatment modalities, and image findings of BM. Factors associated with survival were evaluated, and the patients were divided into three prognostic groups (Groups A, B, and C) for comparative analysis.

RESULTS

The median age at BM was 63 years, and the median time from initial thyroid cancer diagnosis to BM was 3.8 years. The median survival and the 1-year actuarial survival rate after BM were 8.8 months and 47%, respectively. According to univariate and multivariate analyses, four good prognostic factors (GPFs) were identified including age ≤ 60 years, PS ≤ ECOG 2, ≤ 3 BM sites, and without extracranial metastasis prior to BM. Three prognostic groups were designed based on age and number of remaining GPFs: patients ≤ 60 years of age with at least 2 GPFs (Group A) had the most favorable prognosis with a median survival of 32.8 months; patients ≤ 60 years of age with fewer than 2 GPFs and those > 60 years of age with at least 2 GPFs (Group B) had an intermediate prognosis with a median survival of 9.4 months; and patients > 60 years of age with fewer than 2 GPFs (Group C) had the least favorable prognosis with a median survival of 1.5 months.

CONCLUSIONS

The survival of patients with BM form DTC differed among the prognostic groups based on the total number of good prognostic factors.

Long-term survival in a patient with brain metastases of papillary thyroid carcinoma

We present the case of a 43-year-old woman who underwent total thyroidectomy with bilateral lymphadenectomy for a papillary thyroid carcinoma (PTC), solid variant (T4bN1bMx), with V600E BRAF mutation. After ablative therapy, she presented undetectable thyroglobulin (Tg) but progressively increasing anti-Tg antibodies (TgAbs). During follow-up, nodal, lung and brain metastases were identified. She was submitted to surgical excision of lung lesions, radiosurgery of brain metastases and five radioiodine treatments. The latest brain MRI showed no lesions, pulmonary CT showed stable micronodules and there was progressive reduction in TgAbs. This is a peculiar case of a PTC with lung and brain metastatic lesions detected through TgAbs. Initial histological and molecular study suggested a more aggressive clinical behaviour, which was eventually confirmed. Although PTC brain metastases are extremely rare and present poor prognosis, our patient presented a good response to treatment and longer survival than usually reported for similar cases.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

Clinical characteristics and follow-up of intracranial metastases from thyroid cancer

BACKGROUND

Intracranial metastasis from thyroid cancer is extremely rare. However, less is known about the risk factors for intracranial metastasis and its treatment from few retrospective studies. The aim of this study was to contribute to the understanding of this disease by analyzing patients with intracranial metastases from thyroid cancer.

METHODS

Between 2001 and 2014, the database of the National Cancer Center of Korea was searched for thyroid cancer patients. The clinical characteristics and site of distant metastasis according to the histological type were evaluated in the thyroid cancer cohort. Among the patients with intracranial metastases, the characteristics, histological type of primary cancer and metastatic brain tumor, additional synchronous or previous distant metastasis, treatment modalities, locations and characteristics on radiologic findings, time interval between the first diagnosis of the primary thyroid cancer and brain metastasis, thyroglobulin level at the first detection of intracranial metastasis and survival were reviewed.

RESULTS

A total of 10 (0.032 %) out of 3,090 thyroid cancer patients in the National Cancer Center database were identified as having intracranial metastases. The histological types of the primary thyroid cancers were papillary for six patients, follicular for three, and poorly differentiated carcinoma for one. Six of these ten patients underwent surgical resection for intracranial lesions. Whole-brain radiotherapy or tyrosine kinase inhibitors were applied to the patients as postoperative adjuvant treatment, and stereotactic radiosurgery was considered for recurrent or surgically inoperable lesions. The overall median survival time was 33 months (range, 0.5-78 months) after diagnosis of intracranial metastasis.

CONCLUSIONS

Surgical resection and adjuvant treatments in the contemporary era seem to result in improved survival after intracranial metastases compared with what has been reported in past studies. Considering the grave course of intracranial metastasis, the early detection and aggressive treatment of patients with a good performance status are crucial.

Correlative Studies in Clinical Trials: A Position Statement From the International Thyroid Oncology Group

OBJECTIVE

Patients with progressive thyroid cancer in distant metastatic sites represent a population with a need for new therapeutic options. Aspiring to improve the treatment of such patients, the objective of this position statement from the International Thyroid Oncology Group (ITOG) is to clarify the importance of incorporating high-quality correlative studies into clinical trials.

PARTICIPANTS

ITOG was formed to develop and support high-quality multicenter and multidisciplinary clinical trials for patients with aggressive forms of thyroid cancer. The Correlative Sciences Committee of the ITOG focuses on the quality and types of correlative studies included in ITOG-associated clinical trials.

EVIDENCE

This document represents expert consensus from ITOG regarding this issue based on extensive collective experience in clinical and translational trials informed by basic science.

CONSENSUS PROCESS

The Correlative Studies Committee identified an international writing group representative of diverse specialties, including basic sciences. Drafts were reviewed by all members of the writing group, the larger committee, and the ITOG board. After consideration of all comments by the writing group and modification of the document, the final document was then approved by the authors and the ITOG board.

CONCLUSIONS

High-quality correlative studies, which include variety in the types of correlates, should be intrinsic to the design of thyroid cancer clinical trials to offer the best opportunity for each study to advance treatment for patients with advanced and progressive thyroid cancer.