Clinical Effect Observation of Apatinib Combined with 131I for Radioiodine-Refractory Differentiated Thyroid Cancer and Prognostic Significance Analysis of Macrophage Inflammatory Protein-1alpha After Treatment: A Cell Regulation Study / Observación del Efecto Clínico de Apatinib Combinado con 131I para el Cáncer de Tiroides Diferenciado Resistente al Yodo Radiactivo y Análisis de Importancia Pronóstica de la Proteína Inflamatoria 1alfa de Macrófagos Después del Tratamiento: Un Estudio de Regulación Celular

SUMMARY: The objective of this study was to observe the clinical efficacy of apatinib (AP) combined with 131I in the treatment of radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) and the prognostic significance of MIP-1α after treatment, and to provide reference and guidance for future treatment and disease assessment of RAIR-DTC. One hundred and six patients with RAIR- DTC admitted to our hospital from January 2019 to October 2020 were selected for the study. All the patients were treated with TC surgery with 131I at our hospital, and 58 of them were subsequently transferred to AP treatment, which was considered as the research group; the other 48 patients were transferred to thyroid stimulating hormone (TSH) suppression treatment, which was considered as the control group. The clinical efficacy of the research group was better than that of the control group (P 0.05). After treatment, Tg, TL, maximum diameter of C/B lymph nodes, number of lymph nodes and number of calcified spots were lower in the research group than in the control group (P < 0.05). ROC analysis revealed that the predictive sensitivity of MIP-1α for prognosis of 3-year RAIR-DTC death in the research group of patients was 84.63 % and the specificity was 72.16 %. AP combined with 131I is effective in the treatment of RAIR-DTC and is worth using in the clinical practice. In addition, elevated levels of MIP-1α predicted a poor prognosis for patients with RAIR-DTC.

El objetivo de este estudio fue observar la eficacia clínica de apatinib (AP) combinado con 131I en el tratamiento del cáncer de tiroides diferenciado refractario al yodo radiactivo (RAIR-DTC) y la importancia pronóstica de MIP-1α después del tratamiento, y proporcionar referencia y orientación para futuros tratamientos y enfermedades. Evaluación de RAIR- DTC. Se seleccionaron para el estudio 106 pacientes con RAIR- DTC ingresados en nuestro hospital desde enero de 2019 hasta octubre de 2020. Todos los pacientes fueron tratados con cirugía CT con 131I, y 58 de ellos fueron trasladados posteriormente a tratamiento AP, los que fueron considerados como grupo de investigación; los otros 48 pacientes fueron transferidos a tratamiento de supresión de la hormona estimulante de la tiroides (TSH), que se consideró como grupo de control. La eficacia clínica del grupo de investigación fue mejor que la del grupo de control (P 0,05). Después del tratamiento, Tg, TL, diámetro máximo de los linfonodos C/B, número linfonodos y número de manchas calcificadas fueron menores en el grupo de investigación que en el grupo de control (P <0,05). El análisis ROC reveló que la sensibilidad predictiva de MIP-1α para el pronóstico de muerte por RAIR-DTC a 3 años en el grupo de pacientes de investigación fue del 84,63 % y la especificidad fue del 72,16 %. AP combinado con 131I es eficaz en el tratamiento del RAIR-DTC y vale la pena utilizarlo en la práctica clínica. Además, los niveles elevados de MIP-1α predijeron un mal pronóstico para los pacientes con RAIR- DTC.

Meta-analysis of the efficacy of tyrosine kinase inhibitor in radioiodine-refractory differentiated thyroid carcinoma / 中国现代医生

Objective To investigate the effect of tyrosine kinase inhibitor(TKI)on radioiodine-refractory differentiated thyroid carcinoma(RAI-rDTC).Methods Literature related to RAI-rDTC was retrieved from Wanfang Data,CNKI,VIP,PubMed,Cochrane,EmBase and Medline databases until December 31,2021.Literature quality and experimental bias were referred to the Cochrane quality risk assessment table,and Meta-analysis was performed using RevMan 5.3 software.Results A total of 1384 patients were included in 6 studies.The results of Meta-analysis showed that the median progress free survive(HR=0.30,95%CI:0.18-0.50,P<0.00001)and overall survival(HR=0.70,95%CI:0.57-0.88,P=0.002)in treatment group were significantly longer than those in control group.There was no significant difference in complete response between two groups(RR=3.31,95%CI:0.41-26.89,P=0.26).The partial response in treatment group was significantly higher than that in control group(RR=15.97,95%CI:3.48-73.17,P=0.0004).The incidence of TKI-related adverse reactions above grade 3 in treatment group was significantly higher than that in control group(RR=2.91,95%CI:1.70-4.96,P<0.0001).Conclusion TKI can significantly prolong progress free survive and overall survival in patients with RAI-rDTC,but there are still many adverse reactions.It is necessary to comprehensively evaluate the health status of patients before medication.

Progress on Targeted Therapy of Radioiodine-refractory Differentiated Thyroid Cancer / 肿瘤防治研究

Targeted therapy has brought revolutionary breakthroughs for radioiodine-refractory differentiated thyroid cancer. New targeted drugs have prolonged the survival of patients with advanced differentiated thyroid cancer. Multiple tyrosine kinase inhibitors, represented by sorafenib and lenvatinib, have remarkably improved the progression-free survival of patients. Novel tyrosine kinase inhibitors targeting BRAF and RET mutation have also achieved remarkable curative effects, greatly enriching the treatment methods for thyroid cancer. This article reviews the latest research progress on targeted therapy in radioiodine-refractory differentiated thyroid cancer.

Radioactive concentration of 131I in the air of treatment workplaces for differentiated thyroid cancer with sodium iodide 131I oral solution / 中国辐射卫生

Objective To study the radioactive concentration of 131I in the air of workplaces where sodium iodide [131I] oral solution was administrated for patients with differentiated thyroid cancer (DTC) in the Department of Nuclear Medicine, and to estimate the internal radiation dose to the staff. Methods Workplaces of radioiodine 131I therapy for DTC patients in the Department of Nuclear Medicine of a hospital were investigated. Air samples in 131I administration areas and treatment wards were collected respectively and were measured by low-background gamma-ray spectrometry to calculate the activity concentration of 131I in the air and to further estimate the internal radiation dose to staffs. Results The activity concentration in the 131I administration area within the first 3 h of administration was 3～187 Bq/m3. During administration and within the first 3 h of administration, the staff exposed in the administration area for 5～30 min received an internal radiation dose of 0.08～0.50 μSv and 0.00～0.04 μSv, respectively. The highest activity concentration of 131I in the air of the ward was measured on the day of administration, reaching 3091 Bq/m3. After patients were discharged, the activity concentration in the ward gradually decreased to 10～242 Bq/m3 within 48 h. Within 48 h after patients were discharged, the staff exposed in the ward for 5～30 min received an internal radiation dose of 0.01～14.11 μSv. Conclusion A high activity concentration of 131I in the air was recorded during administration for DTC patients in radioiodine 131I therapy, and thus we recommend remote instructed administration or administration through a shielded window. We also recommend that non-treatment related personnel except medical staffs should not enter the ward during patients’ hospitalization at which the activity concentration of 131I in the ward was the highest. After patients were discharged, a delayed entry into the ward is recommended to reduce the internal radiation dose.

Progress in Re-differentiating Therapy of Radioiodine-refractory Differentiated Thyroid Cancer / 肿瘤防治研究

The majority patients of differentiated thyroid carcinoma (DTC) with indolent progression have general good prognosis after standard primary treatments including surgery, thyroid stimulating hormone (TSH) suppression and radioactive iodine (RAI) therapy. However, there are still some patients suffered from recurrence or distant metastasis after initial treatment. They may lose the ability of uptaking iodine during their natural course of disease or treatment and could not benefit from subsequent RAI treatment, which will result in radioiodine-refractory differentiated thyroid cancer (RAIR-DTC). Options are very limited for RAIR-DTC patients, which is associated with a poor prognosis. Recently, with the research advances on the molecular mechanism of RAIR-DTC, redifferentiation combined with RAI therapy have been increasingly used to treat RAIR-DTC, and some outcomes are quite encouraging. This paper reviews the progress of signaling pathway inhibitors, histone deacetylase inhibitors, DNA methyltransferase inhibitors, retinoids and peroxisome proliferator-activated receptor agonists in redifferentiating therapy of RAIR-DTC.

El tratamiento paciente específico del hipertiroidismo con radioyodo: una oportunidad a la mejora / Radioiodine treatment of hyperthyroidism with patient-specific techniques: an improvement opportunity

Introducción: La aplicación de actividades fijas en el tratamiento del hipertiroidismo con I131 (yoduro de sodio, conocido también como radioyodo), es el método más usado en nuestro país, a pesar de la individualidad morfo-funcional que caracteriza esta afección. Sin embargo, no existe aún, un consenso internacional sobre la dosis más conveniente para cada caso, y por ende, los resultados no siempre son los deseados. Objetivo: Evaluar la aplicabilidad de varios métodos de cálculo de dosis paciente-específica para el tratamiento de hipertiroidismo con yoduro de sodio. Métodos: Se realizó un análisis de los resultados de varios métodos de cálculo de dosis recomendados internacionalmente a partir de la actividad fija prescrita en 10 pacientes, con el empleo de tecnologías y herramientas ya desarrolladas y disponibles en el país. Se evaluó la variabilidad inter-especialista y su impacto en la dosis planificada para el tratamiento. Resultados: El uso de la información incompleta de la biodistribución y farmacocinética del paciente produjo diferencias entre -42 por ciento y 37 por ciento de las dosis para el mismo paciente. El resultado de la comparación del método de cálculo recomendado por la Sociedad Europea de Medicina Nuclear, manejando la masa por gammagrafía-2D / 3D y por ultrasonido, arrojó diferencias no significativas entre sí. La variabilidad inter-especialista de las actividades prescrita mostró diferencias significativas, que arrojan sobre el mismo paciente, discrepancias entre 44Gy y 243Gy de las dosis terapéuticas a recibir, situación que puede comprometer el éxito del tratamiento y producir efectos secundarios no deseados. Conclusiones: Las técnicas dosimétricas paciente-específicas se pueden implementar satisfactoriamente en nuestro país. Las diferencias numéricas encontradas, especialmente la variabilidad inter-especialista, demuestran la no estandarización terapéutica, lo que apoya el uso de la farmacocinética paciente-específica pre terapéutica y la masa por gammagrafía-3D para planificar el tratamiento siempre que sean posible(AU)

Introduction: Despite of its typical morpho-functional individuality, fixed activities remain as the most used method in Cuba for hyperthyroidism treatment with I (sodium iodide, also known as radioiodine). However, there is not yet an international consensus on the most convenient doses for each case, so, the results are not always the desired ones. Objective: To evaluate the applicability of various patient-specific dose calculation methods for the treatment of hyperthyroidism with sodium iodide. Methods: It was carried out an analysis in 10 patients of the results of some methods for dose calculation from the prescribed fixed activity recommended internationally, with the use of technologies and tools already developed and available in the country. The inter-specialist variability and its impact in the planned dose for the treatment were assessed. Results: The use of uncompleted biodistribution and pharmacokinetics information of the patient showed differences between -42 percent and 37 percent in the doses for the same patient. The outcome of the comparison of the calculation method recommended by the European Society of Nuclear Medicine managing the mass by 3D/2D gammagraphy and ultrasound, presented no significant discrepancies among them. The inter-specialist variability of prescribed activity was statistically significant, and it can produce in the same patient differences between 44Gy and 243Gy of the therapeutic doses, which could affect the treatment success and lead to unnecessary side effects. Conclusions: The patient´s personalized calculation methods can be satisfactorily applied in Cuba. The numeric differences found, especially inter-specialist variability, show the lack of therapeutic standardization, which supports the use of pre-therapeutic patient-specific pharmacokinetics and the mass by 3D-gammagraphy to plan the treatment when possible(AU)

Added value of postoperative Radioiodine Scan for staging and risk Stratification in Papillary Thyroid Microcarcinoma / Journal of the ASEAN Federation of Endocrine Societies

Objective@#The complete staging and risk stratification of Papillary thyroid microcarcinoma (PTMC) is usually not done due to its theoretically low recurrence rates. This study aimed to determine the value of postoperative radioiodine diagnostic scan and SPECT/CT for the accurate staging and risk stratification in PTMC patients.@*Methodology@#This study was a retrospective review of PTMC patients from January 2014 to May 2017 who underwent I-131 scans. All PTMC patients were initially staged by the 8th edition AJCC/TNM staging system and risk-stratified, based on clinical information, histopathology and stimulated thyroglobulin (sTg). After I-131 scan, staging and risk stratification were re-assessed. The proportion of patients who ended up with a higher stage and risk stratification were reported.@*Results and Conclusion@#Fifty-two patients were included. The overall upgrading of cancer stage was 7.7 %. The overall higher risk stratification was 19.2% with radioiodine-avid lymph node, lung, and bone metastases. Neck and paratracheal node metastases were found in 37.3% of the initial low-risk patients with sTg less than 5 ng/mL. Lung metastasis was found in the initial intermediate-risk patient. The I-131 scan helps to localize metastatic lesions and results in a higher stage in 50% of the initial high-risk patients. This study provides some evidence showing the value of postoperative radioiodine WBS for accurate staging and risk stratification in PTMC patients. Larger studies with analytical design should be further performed to prove its significant utility.

Patterns of radioiodine use for differentiated thyroid carcinoma in Brazil: insights and a call for action from a 20-year database

ABSTRACT Objective: This study aimed to explore the patterns of radioactive iodine (RAI) use for differentiated thyroid cancer (DTC) in Brazil over the past 20 years. Materials and methods: A retrospective analysis of the DTC-related RAI prescriptions, from 2000 to 2018, retrieved from the Department of Informatics of the Unified Health System (Datasus) and National Supplementary Health Agency (ANS) database was performed. RAI activities prescriptions were re-classified as low (30-50 mCi), intermediate (100 mCi), or high activities (>100 mCi). Results: The number of DTC-related RAI prescriptions increased from 0.45 to 2.28/100,000 inhabitants from 2000 to 2015, declining onwards, closing 2018 at 1.87/100,000. In 2018, population-adjusted RAI prescriptions by state ranged from 0.07 to 4.74/100,000 inhabitants. Regarding RAI activities, in the 2000 to 2008 period, the proportion of high-activities among all RAI prescriptions increased from 51.2% to 74.1%. From 2009 onwards, there was a progressive reduction in high-activity prescriptions in the country, closing 2018 at 50.1%. In 2018, the practice of requesting high-activities varied from 16% to 82% between Brazilian states. Interestingly, variability of RAI use do not seem to be related to RAI referral center volume nor state socio-economic indicators. Conclusion: In recent years, there has been a trend towards the lower prescription of RAI, and a reduction of high-activity RAI prescriptions for DTC in Brazil. Also, significative inter-state and inter-institutional variability on RAI use was documented. These results suggest that actions to advance DTC healthcare quality surveillance should be prioritized.

Supervivencia prolongada luego de pequeñas dosis de terapia con radioyodo en metástasis cerebral de cáncer de tiroides / Long-term survival after small doses of radioiodine therapy for brain metastases of thyroid cancer

Resumen El cáncer diferenciado de tiroides generalmente se acompaña de una supervivencia a largo plazo. Sin embargo, en algunos casos pueden desarrollarse metástasis a distancia y, entre ellas, las localizaciones cerebrales son de mal pronóstico. El objetivo de esta presentación es comunicar el caso clínico de una mujer de 65 años que consultó por diplopía en la mirada vertical que había aparecido un mes antes. La resonancia magnética mostró una gran masa a nivel del cóndilo occipital. Se realizó el diagnóstico de tumor cerebral primario, por lo que fue operada dos veces con resección tumoral incompleta. El estudio histopatológico confirmó una lesión metastásica de carcinoma de tiroides. Se realizó una tiroidectomía total con resección de un cáncer papilar de la variante folicular. Luego, fue tratada con éxito con pequeñas cantidades repetitivas de yodo radiactivo para una dosis total acumulada de 325 mCi 131I, con una supervivencia a largo plazo.

Abstract Differentiated thyroid cancer is generally accompanied by a long term survival. However,in some cases distant metastases can develop and among them, brain localizations are of poor prognosis. The aim of this presentation is to communicate the clinical case of a 65 year-old woman who consulted for diplopia in vertical gaze which had appeared one month earlier. MRI showed a big mass at the level of the occipital condyle. Diagnosis of primary brain tumor was made so she was operated twice with incomplete tumor resection. The pathological study was confirmatory of a metastatic lesion of thyroid carcinoma. A total thyroidectomy with resection of a papillary cancer of the follicular variant was performed. Then, she was successfully treated with small repetitive radioiodine amounts for a total accumulated dose of 325 mCi 131I, with a long-term survival.

Administración de radioyodo en cáncer diferenciado de tiroides bajo régimen hospitalario: a propósito de la implementación del aislamiento de radioyodoterapia en un hospital regional / Administration of radioiodine in differentiated thyroid cancer under a hospital regime: about the implementation of radioiodotherapy isolation in a regional hospital

Resumen Introducción El cáncer diferenciado de tiroides (CDT) presenta un aumento a nivel mundial. El uso selectivo de terapia con radioyodo (RAI) es un pilar de su tratamiento. Su efecto terapéutico se debe a la radiación beta, mientras que la gamma hace que sea necesaria la hospitalización para limitar la exposición de terceros. Objetivo Describir la seguridad de la administración de altas dosis de RAI en pacientes con CDT. Materiales y Método Estudio retrospectivo descriptivo. Se incluyó a todos los pacientes con diagnóstico de CDT que requirieron hospitalización para administración de RAI ≥ 30 mCi en el Hospital Regional de Talca (HRT) entre agosto-diciembre de 2018. Resultados Durante el período descrito 10 pacientes recibieron RAI bajo régimen hospitalario. La mediana de dosis de RAI administrada fue de 100 mCi (rango: 50-150 mCi). Todos los pacientes fueron manejados con asilamiento estricto. El promedio de hospitalización fue 28 horas, siendo dados de alta al reportar una tasa de dosis absorbida < 70 µSv/h a 1 metro. Se entregaron instrucciones al alta para minimizar el riesgo de irradiación o contaminación a terceras personas. Conclusiones Nuestro protocolo de administración de RAI permite tratar de manera segura a pacientes con CDT disminuyendo la exposición a radiación de terceros. Las salas de asilamiento de radioyodoterapia, podrían dar cobertura al 100% de la demanda de terapia con RAI en CDT a nivel local.

Introduction Differentiated thyroid cancer (CDT) presents an increase in global levels. The selective use of radioiodine therapy (RAI) is a pillar of its treatment. Its therapeutic effect is due to beta radiation, while gamma makes hospitalization necessary to limit exposure. Aim To describe the safety treated with RAI inpatients and the functioning of the radioactive isolation rooms of our center. Materials and Method Retrospective descriptive study. All patients diagnosed with CDT who required RAI therapy under a hospital regimen at the Regional Hospital of Talca (HRT) between August-December 2018 were included. Results During the period described, 10 patients were treated. The median dose of RAI administered was 100 mCi (range: 50-150 mCi). The average of hospitalization was 28 hours, being discharged when reporting an absorbed dose rate < 70 μSv/h at 1 meter, giving the patient instructions, so that they follow to minimize the risk of irradiation or contamination of people in their environment. Conclusions Our RAI administration protocol allows patients with CDT to be treated safely. The radioactive isolation rooms could cover 100% of the demand for RAI therapy in CDT at the local level.

Microscopic extrathyroid extension in papillary thyroid carcinoma: impact on response to therapy

ABSTRACT Objectives Evaluate the impact of microscopic extrathyroid extension (MEE) on outcome and therapy response in patients with cT1 and cT2 papillary thyroid carcinoma (PTC). Subjects and methods Retrospective study of 970 consecutive patients, who underwent surgery for PTC between 2000 and 2016. All patients had: tumours ≤ 4 cm, apparent complete tumour resection, without clinically apparent lymph node or distant metastasis at diagnosis and nonaggressive histologic variant. Results Based on the finding of MEE, 175 (18.0%) patients were upstaged to T3. They were older (53.9 versus 50.6 years; P = 0.004) and were more prone to have multifocal tumours (38.2% versus 24.8%; P = 0.001). Radioiodine ablation therapy (RAI) was administered more often to MEE patients (92% versus 40.5%; P < 0.001), as well as prophylactic lymph node resection (35.4% versus 28.6%, P = 0.048). They were more likely to have biochemical incomplete response (4% versus 0.3%; P = 0.03) at the end of the follow-up period. There was no significant association between MEE and recurrence rate, persistence of disease or disease-specific mortality. Conclusion These results support the changes made to the latest edition of the TNM staging system, regarding MEE. Although incomplete biochemical response is more common in these patients, it does not seem to affect their prognosis.

Resultados a corto plazo del tratamiento con 131I en el bocio multinodular: valor adicional de la estimulación previa con rhTSH / Short-term results of treatment with 131I in multinodular goiter: additional value of previus stimulation with Recombinant human thyrotropin

OBJETIVO: El yodo radiactivo (131I) es una opción terapeútica segura y eficaz cuando se utiliza solo o con la estimulación previa de TSH recombinante humana (rhTSH) en el tratamiento del bocio multinodular (BMN). En espera de ensayos clínicos que determinen la dosis óptima, demuestren seguridad y confirmen la eficacia, diferentes protocolos se utilizan para aplicar la dosis de 131I. Analizamos la respuesta al tratamiento con una dosis calculada por protocolo mixto (dosis fijas y cálculo por porcentaje de captación) en pacientes con BMN toxico y no toxico en nuestro hospital, en el periodo 2010-2013. MATERIALES Y MÉTODOS: Estudio prospectivo en pacientes con BMN no quirúrgico (BMNNQ) que requerían reducción del volumen glandular y/o tratamiento del hipertiroidismo. Se evaluaron 134 pacientes, 14 cumplieron con los criterios de inclusión (13mujeres) de edad media 71.08 años. Un grupo con BMN toxico, otro grupo con BMN no toxico, un tercer grupo con BMN no toxico estimulado con 0,1 mg de rhTSH previo a la dosis. Se evaluó, función tiroidea, captación tiroidea de 99ᵐTc, volumen tiroideo y síntomas compresivos. Se siguió a los pacientes durante 12 meses. RESULTADOS: Se aplicaron dosis entre 15 y 30 mCi de 131I. Remitió el hipertiroidismo en 6 de 7 pacientes. Hubo una reducción del volumen glandular (p<0.01).Los pacientes con estímulo de 0,1 mg rhTSH, aumentaron el porcentaje de captación de 99ᵐTc a las 24 h en un 32.43±10.61 permitiendo aplicar menor dosis de 131I. La tasa de aparición de hipotiroidismo fue de 7.41 por cada 100 pacientes.mes, mayor en pacientes con BMN toxico tratados con dosis bajas (p-=0.03). Hubo una mejoría subjetiva de la clínica compresiva en todos los pacientes. No hubo eventos adversos. CONCLUSIONES: Una dosis de 131I calculada por protocolo mixto es efectiva y segura para la reducción del volumen glandular y control del hipertiroidismo asociado. La estimulación con rhTSH logra el mismo efecto con una menor dosis administrada.

OBJECTIVE: Radioactive iodine (131I) is a safe and effective therapeutic option when used alone or with prior stimulation of recombinant human Thyrotropin (rhTSH) in the treatment of multinodular goiter (MNG). In absence of clinical trials that determine the optimal dose, demonstrate safety and confirm efficacy, different protocols are used to apply the dose of 131I. We analyze the response to treatment with a dose calculated by mixed protocol (fixed doses and calculation by percentage of uptake) in patients with toxic and non-toxic MNG in our hospital, in the period 2010-2013. MATERIALS AND METHODS: Prospective study in patients with non-surgical MNG that required glandular volume reduction and / or treatment of hyperthyroidism. 134 patients were evaluated, 14 met the inclusion criteria (13 women) of average age 71.08 years. One group with toxic MNG, another group with non-toxic MNG and a third with non-toxic multinodular goiter stimulated with 0.1 mg of rhTSH prior to the dose. Patients were followed for 12 months. Upon following, we assessed Thyroid function, 99ᵐTc thyroid uptake, thyroid volume and compressive symptoms. RESULTS: Doses between 15 and 30 mCi of 131I were applied. We observed hyperthyroidism remission in 6 of 7 patients. There was a reduction in glandular volume (p <0.01) considering all patients. Patients with a stimulus of 0.1 mg rhTSH, increased the percentage of uptake of 99ᵐTc at 24 h by 32.43 ± 10.61, allowing a lower dose of 131I to be applied. The rate of onset of hypothyroidism was 7.41 per 100 patients-month, and was higher in patients with toxic MNG treated with low doses (p = 0.03). There was a subjective improvement of the compression clinic in all patients. No adverse events were observed. CONCLUSIONS: A dose of 131I calculated by a mixed protocol is effective and safe for achieving glandular volume reduction and associated hyperthyroidism control. Stimulation with rhTSH produces the same effect with a lower administered dose.

Variación de dosis de radioyodo en pacientes con cáncer diferenciado de tiroides post implementación de guías ATA 2015 / Variation of radioiodine dose in patients with differentiated thyroid cancer after implementation of the ATA 2015 guidelines

Introducción: El cáncer diferenciado de tiroides (CDT), es actualmente la neoplasia endocrina más frecuente. Su tratamiento estándar es la resolución quirúrgica, asociado a ablación con radioyodo (RI) según la clasificación propuesta por la American Thyroid Association (ATA). Las indicaciones y dosis de este último, han ido variando en los últimos años según avanzan las investigaciones en este ámbito. Objetivo: En el siguiente estudio se compararon las dosis de RI utilizadas previo y posterior a la implementación de las últimas guías de la ATA. Materiales y métodos: Estudio retrospectivo observacional de 70 pacientes con diagnóstico de CDT del Hospital Clínico de la Universidad de Chile entre 2012 y 2017. Se agruparon los pacientes en dos cohortes, los operados entre los años 2012-2015 y los 2016-2017 clasificándolos según riesgo ATA, TNM y riesgo de recurrencia. Se consignaron las dosis de RI utilizadas y se compararon entre las cohortes. Análisis estadístico: Mann Whithney. Resultados: Al comparar la dosis de RI entre ambas cohortes, según TNM y riesgo ATA, se obtuvo los siguientes resultados: los pacientes T1b de la cohorte 2012-2015 presentaron dosis de RI significativamente mayores que los de la cohorte 2016-2017; también se evidenció que en pacientes N0 hubo una diferencia estadísticamente significativa, mostrando una tendencia a disminuir la dosis de RI; además, en los pacientes de la cohorte 2012-2015 con riesgo ATA intermedio, se obtuvo que las dosis de RI fueron significativamente mayores que las utilizadas en la cohorte 2016-2017. Conclusión: Se concluye que las variaciones de las dosis de RI utilizadas en pacientes con CDT en un hospital universitario van acorde a las recomendaciones internacionales actuales, particularmente la publicación de la guía ATA 2015, aplicándose radioablación con menor dosis de RI. Dado este cambio, se ha evidenciado igualdad de efectos con dosis menores de RI y consecuentemente menos efectos adversos.

Introduction: Differentiated thyroid cancer (CDT) is currently the most frequent endocrine neoplasia. Its standard of care is surgical treatment, associated with radioiodine ablation (IR) according to the classification proposed by the American Thyroid Association (ATA). The indications and doses of the latter have changed in recent years as research in this area advances. Objective: In the following study, the doses of IR used before and after the implementation of the latest ATA guidelines were compared. Materials and methods: Retrospective observational study of 70 patients with a diagnosis of CDT from the Clinical Hospital of the University of Chile between 2012 and 2017. Patients were grouped into two cohorts, those surgically intervened between the years 2012-2015 and 2016-2017, classifying them according to ATA risk, TNM and recurrence risk. The IR doses used were reported and compared between the cohorts. Statistical analysis: Mann Whithney. Results: When comparing the IR dose between both cohorts, according to TNM and ATA risk, the following results were obtained: T1b patients in the 2012-2015 cohort had significantly higher IR doses than those in the 2016-2017 cohort; It was also evidenced that N0 patients showed a statistically significant tendency to decrease the IR dose; In addition, the 2012-2015 cohort with intermediate ATA risk, revealed IR doses significantly higher than those used in the 2016-2017 cohort. Conclusion: It is concluded that the variations in IR doses, used in patients with CDT in a university hospital, are in accordance with current international recommendations, particularly the publication of the ATA 2015 guidelines, applying radioablation with a lower dose of IR. Given this change, equality of effects has been evidenced with lower doses of IR and consequently fewer adverse effects.

Ultrasonography Echotexture as a surrogate for Sialadenitis secondary to 131I Radioiodine Therapy for differentiated Thyroid Cancer: a review and metaanalysis

To systematically review and analyze the medical literature to assess ultrasonography echotexture changes in thyroid cancer patients for the detection of chronic sialadenitis caused by radioiodine therapy. Methods: Sources were retrieved from PubMed, Scopus, EMBASE and LILACS through November 2018. All studies that assessed ultrasonographic features before 131I administration and at 12 months after 131I administration were selected. After data extraction, statistical analysis was performed by using Stata software. Results: From a total of 435 studies, 4 studies involving 665 patients were considered eligible, and echotexture heterogeneity was found with a significant difference. Conclusions: Ultrasound echotexture may detect chronic sialadenitis secondary to salivary radioiodine therapy.

In properly selected patients with differentiated thyroid cancer, antithyroglobulin antibodies decline after thyroidectomy and their sole presence should not be an indication for radioiodine ablation

ABSTRACT Objective Our objective was to evaluate the trend of antithyroglobulin antibodies (TgAb) during follow-up of patients with differentiated thyroid cancer (DTC) treated without RAI, as well as their role in the risk of recurrence. Subjects and methods This was a prospective, descriptive study. A total of 152 consecutive patients with DTC treated in a single institution undergoing total thyroidectomy without RAI and followed for a median of 2.3 years (0.5-10.3) were divided in two groups: TgAb(-) (n = 111) and TgAb(+) (n = 41). Patients were classified according to AJCC 7th and 8th editions, as well as to their risk of recurrence and response to treatment categories. Results Both groups, TgAb(-) and TgAb(+), were similar regarding patient and tumor characteristics. At the end of follow-up, 90 (59.2%), 57 (37.5%), 3 (2%) and 2 (1.3%) patients achieved excellent, indeterminate, biochemically incomplete and structurally incomplete response, respectively. The risk of structural recurrence was similar in both groups (TgAb[-] 0.9% vs. TgAb[+] 2.4%, p = 0.46). In the TgAb(+) group, TgAb became negative in 10 (24.4%), decreased ≥ 50% without negativization in 25 (60.9%), decreased < 50% in 4 (9.8%) and remained stable or increased in 2 (4.9%) cases. The only incomplete structural response had increasing TgAb during follow-up. Conclusions In properly selected patients with DTC, TgAb concentration immediately after total thyroidectomy should not mandate RAI ablation, and their trend during follow-up may impact the risk of recurrence.

(99m)Tc-Pertechnetate Scintigraphy Predicts Successful Postoperative Ablation in Differentiated Thyroid Carcinoma Patients Treated with Low Radioiodine Activities

BACKGROUND: Postoperative routine radioiodine (RAI) treatment is currently debated for patients with low-risk differentiated thyroid carcinoma (DTC) patients. If performed, a low 131I activity (i.e., 1 to 2 GBq) is recommended with the aim to ablate thyroid remnant and facilitate subsequent follow-up by thyroglobulin measurement. The purpose of this study was to evaluate the relationship between postsurgical technetium-99m (99mTc)-pertechnetate scintigraphy and the rate of successful remnant ablation after low activity radioiodine ablation in patients with DTC. METHODS: Enrolled were 193 patients with low risk DTC who underwent total thyroidectomy and RAI ablation with a fixed 1.1 GBq activity of 131I. 99mTc-pertechnetate scans were done and thyrotropin stimulated thyroglobulin (sTg) levels measured just before ablation. Ablation effectiveness was assessed 6 to 12 months later by sTg measurement, neck ultrasound and diagnostic whole body scan. RESULTS: A negative 99mTc-perthecnetate scans was the best predictor of successful ablation (P<0.001) followed by preablative sTg levels <0.8 ng/mL (P=0.008) and 99mTc-pertechnetate uptake rate values <0.9% (P=0.065). Neither sex nor age of the patient at the time of ablation or tumor histology and size showed a significant association with the rate of successful ablation. CONCLUSION: The 99mTc-pertechnetate scintigraphy is a simple and feasible tool to predict effectiveness of low activity 131I thyroid to ablate thyroid remnants in patients with DTC.

Emerging management and its impact on radioiodine refractory differentiated thyroid cancer / 中国实用外科杂志

Differentiated thyroid cancer(DTC) generally carries good prognosis through standard treatment. While,it could dedifferentiate into radioiodine refractory differentiated thyroid cancer(RAIR-DTC),which progresses rapidly with high mortality and limited treatment methods. Recently,along with the increasing of studies on genetic features,signal transduction pathways and immune microenvironment of RAIR-DTC,as well as the development of new radionuclide tracers,more theoretical bases have been provided for the targeted therapy of RAIR-DTC.

Current Status and Growth of Nuclear Theranostics in Singapore / 대한핵의학회잡지

The concept of theranostics, where individual patient-level biological information is used to choose the optimal therapy for that individual, has become more popular in the modern era of ‘personalised’ medicine. With the growth of theranostics, nuclear medicine as a specialty is uniquely poised to grow along with the ever-increasing number of concepts combining imaging and therapy. This special report summarises the status and growth of Theranostic Nuclear Medicine in Singapore.We will cover our experience with the use of radioiodine, radioiodinated metaiodobenzylguanidine, peptide receptor radionuclide therapy, prostate specific membrane antigen radioligand therapy, radium-223 and yttrium-90 selective internal radiation therapy.We also include a section on our radiopharmacy laboratory, crucial to our implementation of theranostic principles. Radionuclide theranostics has seen tremendous growth and we hope to be able to grow alongside to continue to serve the patients in Singapore and in the region.

Lesion-Wise Comparison of Pre-Therapy and Post-Therapy Effective Half-Life of Iodine-131 in Pediatric and Young Adult Patients with Differentiated Thyroid Cancer Undergoing Radioiodine Therapy / 대한핵의학회잡지

PURPOSE: The effective half-life of radioiodine is an important parameter for dosimetry in differentiated thyroid cancer patients, particularly in children. We determined the pre-therapy and post-therapy effective half-life in different types of lesions, i.e., remnant, node, or lung metastases.METHODS: Of 84 patients recruited, 27 were < 18 years (group 1) and the remaining 57 were between 18 and 21 years (group 2). A total of 114 studies were conducted and 253 lesions were analyzed. Serial whole-body scans were acquired at 24, 48, and ≥ 72 h after administration of iodine-131. Region of interests was drawn over lesions to determine counts in the lesion. Time versus counts graphs were plotted and mono-exponentially fitted to determine effective half-life.RESULTS: The post-therapy effective half-life was found to be lesser than pre-therapy effective half-life in all types of lesions and in all groups. Median effective half-life was found maximum in intact lobe, minimum in the lung, and intermediate in remnant and nodes. In the assessment of all lesions together, pre- and post-therapy median and interquartile range (IQR) effective half-life were 59.8 (37–112) h and 48.6 (35.2–70.8) h (p < 0.0001) in group 1, 73.9 (46.2–112.7) h and 60 (57.4–85.9) h (p < 0.0001) in group 2, and 68.6 (41.53–112.36) h and 54.7 (36–80.6) h (p < 0.0001) in combined group, respectively. Importantly, the pre- and post-therapy median effective half-life serially dropped after each successive cycles of iodine-131.CONCLUSIONS: There was a significant difference in pre-therapy and post-therapy effective half-life in all types of lesions. These results may have implications in calculating the correct therapeutic dose in children and in young adults.

Postoperative Radioiodine Treatment within 9 Months from Diagnosis Significantly Reduces the Risk of Relapse in Low-Risk Differentiated Thyroid Carcinoma / 대한핵의학회잡지

PURPOSE: Although postoperative radioiodine (RAI) therapy has been used in patients with differentiated thyroid carcinoma (DTC) for many years, there is still lack of data defining the timing of RAI administration. A retrospective analysis was carried out to answer the question whether the time of postoperative RAI treatment demonstrated any impact on long-term outcomes, particularly in low-risk DTC.MATERIAL: The analyzed group involved 701 DTC patients staged pT(1b)-T₄N₀-N₁M₀, who underwent total thyroidectomy and postoperative RAI therapy. According to the time interval between DTC diagnosis and RAI administration, patients were allocated to one of three groups: up to 9 months (N = 150), between 9 and 24 months (N = 323), and > 24 months (N = 228). Median follow-up was 12.1 years (1.5−15.2).RESULTS: Based on an initial DTC advancement and postoperative stimulated thyroglobulin concentration patients were stratified as a low-, intermediate-, and high-risk group. Low-risk patients, who received RAI therapy up to 9 months, demonstrated significantly lower risk of relapse comparing to those, in whom RAI was administered between 9 and 24 months and after 24 months since DTC diagnosis: 0%, 5.5%, and 7.1%, respectively. Regarding intermediate- and high-risk groups, the differences in the timing of postoperative RAI treatment were not significant.CONCLUSION: If postoperative RAI treatment is considered in low-risk DTC, any delay in RAI administration above 9 months since diagnosis may be related to poorer long-term outcomes.