Determination of Frequency of Type 2 Deiodinase Thr92Ala Polymorphism (rs225014) in 131I-treated Differentiated Thyroid Cancer Patients Undertaking L-thyroxine (L-T4) Suppression Therapy.

Introduction: Type 2 deiodinase (DIO2) enzyme plays a vital role in peripheral T4 to T3 conversion and in the negative feedback regulation of pituitary thyroid-stimulating hormone (TSH) secretion. Thr92Ala polymorphism (rs225014) is a common single-nucleotide polymorphism (SNP) that lowers DIO2 activity and is associated with diverse physiological disorders. Differentiated thyroid cancer (DTC) patients are given L-T4 therapy after total thyroidectomy and 131I treatment to suppress TSH levels. Aim: The aim of the study was to determine the frequency of rs225014 in DTC patients and to investigate its effect on the thyroid function tests (TFTs) and L-T4 dose required to suppress TSH levels. Materials and Methods: The study included a DTC patient group and a control group. TFTs were estimated by RIA/IRMA kits. Genomic DNA of all the subjects was screened for rs225014 SNP by polymerase chain reaction. Results: The frequency of Thr/Thr (wild type), Thr/Ala (heterozygous mutant), and Ala/Ala (homozygous mutant) genotypes in the DTC patients' group was 0.21, 0.52, and 0.27, respectively. T3 levels and T3/T4 ratio were significantly low in the Ala/Ala genotype in the DTC group indicating impaired DIO2 activity. L-T4 dose requirement to suppress TSH levels in the DTC patients harboring rs225014 SNP was not statistically different from the wild-type genotype. Conclusion: The SNP rs225014 was observed to be associated with T3 and T3/T4 ratio but not with the L-T4 dose in DTC harboring SNP suggesting the presence of a compensatory pathway to overcome DIO2 impairment. However, it is essential to study the genetic makeup of DTC patients showing reduced response to TSH suppression to enable quicker decision-making in the implementation of personalized L-T4 dose to prevent any adverse effects.

Radioactive iodine therapy strategies for distinct types of differentiated thyroid cancer: a propensity score-matched analysis.

Background: The management guidelines of radioactive Iodine (RAI) therapy for distinct types of differentiated thyroid carcinoma (DTC) were the same in clinical practice. However, in distinct types DTC, differences in RAI avidity and response existed and the effect of RAI therapy could not be equated. Methods: DTC patients' data in SEER database were extracted to perform retrospective analysis. The differences between case group and control group were compared by chi-square tests. We used Kaplan-Meier statistics and Cox regression analyses to investigate cancer-specific survival (CSS). Propensity score-matched was performed to make 1:1 case-control matching. Results: 105195 patients who receiving total thyroidectomy were identified in SEER database. Compared to papillary thyroid carcinoma (PTC) (52.3%), follicular thyroid carcinoma (FTC) (63.8%) and oncocytic carcinoma of thyroid (OCA) (64.4%) had higher rates of RAI therapy. In the multivariable Cox regression model, RAI therapy was independent prognosis factor in PTC but not in OCA and FTC. In subgroup analysis, RAI therapy could improve prognosis in PTC when gross extrathyroidal extension or lymph node metastases or early survival when distant metastases (DM) were presented. However, OCA and FTC patients with DM rather than regional lesions only could benefit from RAI therapy. High-risk patients receiving RAI therapy showed a better prognosis in PTC but not in OCA and FTC. Conclusion: RAI therapy was an effective treatment for DTC and should be considered individually in PTC, OCA and FTC patients. Our results provided further guideline for treatment selection in DTC.

Male Sex Is Not a Risk Factor for Prognosis in Postoperative Thyroid Cancer Patients: A Propensity Score Matching Study.

PURPOSE: To study whether male sex is a risk factor for prognosis in patients with differentiated thyroid cancer after 131I treatment using the propensity score matching (PSM) method. METHODS: From April 2016 to October 2021, 1948 postoperative differentiated thyroid cancer patients aged 43 (interquartile range: 34, 54) years who received 131I treatment were retrospectively enrolled and divided into male (n = 645) and female groups (n = 1303). The PSM method was adopted to process all data to reduce the influence of data bias and confounding variables. The Mann-Whitney U test and χ2 test were used for data analysis. Multivariate logistic regression was used to analyze the risk factors affecting prognosis, and the receiver operating characteristic curve was used to analyze the relationship between stimulated thyroglobulin (sTg) level, 131I dose, and poor prognosis. RESULTS: Before PSM, the proportion of male patients with poor prognosis was significantly higher than that of female patients. After PSM, there was no difference in the proportion of poor prognosis between male and female groups. Multivariate logistic regression analysis showed that male sex; high T stage, N1b stage, and M1 stage; high sTg level; and high 131I dose were risk factors for poor prognosis before PSM. After PSM, high T stage, M1 stage, high sTg level, and 131I dose were still risk factors but male sex was no longer a risk factor for poor prognosis. CONCLUSIONS: After the reduction of selection bias by PSM, male sex was no longer a risk factor for prognosis after 131I treatment of differentiated thyroid cancer. In addition, high T stage (T3 + T4 stage), M1 stage, sTg ≥10.15 ng/mL, and 131I dose ≥260 mCi were risk factors for poor prognosis.

Radioiodine treatment in hyperthyroid cats: insights into the characteristics of owners and their cats, and owner motivation and perceptions.

OBJECTIVES: Radioiodine (131I) therapy is the most appropriate treatment option for many hyperthyroid cats, as it is minimally invasive and often curative. Nevertheless, 131I treatment is not always pursued by owners. Hence, it is important to obtain more insight into owner satisfaction during and after 131I treatment, and their decision-making process. In this study, we describe the characteristics of owners and their hyperthyroid cats referred for 131I therapy, and determine owners' motivation and how they experienced the 131I treatment of their cat. METHODS: A survey was sent to owners whose cats underwent 131I therapy (n = 1071) between 2010 and 2017 at Ghent University. The survey contained 35 questions with tick-box or free-text answer options concerning family situation, pet insurance, previous therapy, comorbidities, motivation for 131I therapy and owner perception of this treatment. RESULTS: In total, 438 owners completed 94% or more of the questionnaire. Over half of the cats (55%) had received previous medical, dietary or surgical treatment. Motivations for changing the initial therapy to 131I therapy included difficulties in administering medication (31%), insufficient improvement in clinical signs (23%), side effects (16%) and following the referring veterinarian's advice (16%). Almost a fifth of owners (18%) were not informed about the existence of 131I therapy by their veterinarian and found information on 131I treatment online or through friends. Hospitalising their cat was very distressing for 17% of owners. Most owners (92%) were satisfied with the treatment. Reasons for dissatisfaction were insufficient communication, iatrogenic hypothyroidism, persistent hyperthyroidism and comorbidities post-treatment. CONCLUSIONS AND RELEVANCE: Our study stresses the importance of communication regarding the possible outcome of 131I treatment, the importance of managing underlying comorbidities before treatment and anticipating the stress of owners during their cat's hospitalisation period. The results of this study could help in improving client communication when advising on 131I treatment.

Dynamic Risk Stratification for Predicting Long-term Outcomes in Pediatric Differentiated Thyroid Cancers.

CONTEXT: The American Thyroid Association (ATA) guidelines recommend Dynamic Risk Stratification (DRS) for predicting long-term outcomes and personalizing management in adult differentiated thyroid cancers (DTCs). However, its applicability in pediatric DTCs needs to be validated. OBJECTIVE: We have attempted a validation study concerning the use of DRS in pediatric DTCs. METHODS: Data of children (age ≤18 years) with DTCs and follow-up of ≥5 years were extracted. All patients were classified according to DRS (excellent biochemical or structural incomplete responses). Univariate and multivariate analyses were done to identify factor(s) affecting disease-free survival (DFS). RESULTS: We included 176 pediatric patients with DTC (median age at diagnosis 15 years). All patients underwent thyroidectomy and received radioiodine as part of initial management. On the basis of clinical, biochemical, and imaging findings acquired during the first 2 years of follow-up, the DRS system divided patients into 3 response categories: excellent response in 82/176 (46.6%), biochemical incomplete response in 56/176 (31.8%), and structural incomplete response in 38/176 (21.6%) patients. The median follow-up was 10.6 years (interquartile range 7.7-15.5). Ten-year overall survival and DFS rates were 100% and 88.7%, respectively. In univariate analysis, DFS was significantly affected by extrathyroidal extension (P = .002), lymph node metastasis (P = .018), ATA initial risk stratification (P = .033), and DRS (P = .004). However, in multivariate analysis, DRS alone showed a significant association with DFS (P = .016). CONCLUSION: Like adults, DRS correctly predicts long-term outcomes in pediatric DTC. In addition to ATA initial risk stratification, DRS could further refine risk in pediatric DTCs and help in planning more personalized treatment and follow-up strategies.

Radioiodine (131I) treatment decision-making for low- and intermediate-risk differentiated thyroid cancer

ABSTRACT Objective: The purpose of this study was to investigate the effect and influencing factors of post-surgical radioactive iodine (RAI) therapy for patients with low- and intermediate-risk differentiated thyroid cancer (DTC). Subjects and methods: A retrospective analysis of 423 low- and intermediate-risk DTC patients admitted to the Department of Nuclear Medicine, Sichuan Provincial People's Hospital from January 2005 to December 2020 was performed. All patients were treated with surgery, had a postoperative pathological diagnosis, and were treated with RAI, including 89 males and 334 females. Recurrence risk stratification: 143 cases were low-risk, and 280 cases were intermediate-risk. Results: The excellent response (ER) rate for low- and intermediate-risk were 93.7% and 78.2%, respectively (P < 0.05). There were significant differences in age, cumulative dose of [131I], and pretreatment stimulated-Tg (pre-Tg) levels between the low- and intermediate-risk groups (P < 0.05). There were significant differences in the cumulative dose of 131I and pre-Tg levels between ER and the non-ER group (P < 0.05). The area under the curve (AUC) values were 0.799 in the low-risk group, and 0.747 in the intermediate-risk group for the ROC curve by ER status of pre-Tg. The ER rate with RAI treatment decreased with an increase in pre-Tg levels. Conclusion: Pre-Tg was an important factor for RAI treatment decision-making and prognostic evaluation and differed between low-risk and intermediate-risk DTC. Aggressive RAI therapy was recommended for low-risk DTC with pre-Tg ≥ 20.0 ng/mL and in intermediate-risk group with pre-Tg ≥ 10.0 ng/mL.

The Effects of Radioiodine Therapy on the Recovery of Parathyroid Function in Patients with Protracted Hypoparathyroidism after Total Thyroidectomy for Papillary Thyroid Carcinoma.

BACKGROUND: To determine the effect of 131I treatment on postoperative parathyroid function and the timing of recovery of parathyroid function (RPF) in patients with protracted hypoPT. METHODS: 260 patients with papillary thyroid cancer (PTC) were retrospectively analyzed, including 166 patients treated with radioactive iodine-131 (131I) classified into the 131I group and 94 patients without 131I treatment classified into the control group. Data on clinicopathological characteristics, demographics, dose and interval time of 131I treatment, number of parathyroid glands remaining in situ (PGRIS), occurrence of hypoPT, duration of RPF, preoperative and postoperative levels of Ca and PTH were collected. RESULTS: The patients in the 131I group showed a higher persistent hypoPT rate than those in the control group (p = 0). The PGRIS and total number of PG were significantly higher in patients who recovered from protracted HypoPT (p = 0.02; p = 0.03). PGRIS and 131I treatment [1 ∼ 2 VS 0, p = 0.03, OR 3.19; 3 ∼ 4 VS 0, p = 0.02, OR3.62; p = 0.02, OR 1.98, respectively] were independent factors influencing postoperative persistent hypoPT. The timing of RPF differed significantly for patients in the control group compared to those in the 131I group [p = 0.00]. CONCLUSIONS: We found that 131I treatment significantly prolonged the RPF of patients with protracted hypoPT and caused late RPF (even beyond 12 months). The diagnosis of "permanent" hypoPT should be cautiously made at least 12 months after surgery, especially in patients who receive 131I treatment.

Effect of COVID-19 pandemic on diagnosis and treatment of thyroid cancer in Brazil.

Introduction: The COVID-19 pandemic delayed the diagnosis, treatment, and follow-up visits of patients with thyroid cancer. However, the magnitude with which these restrictions affected the Brazilian health care is still unknown. Methods: Retrospective analysis of thyroid cancer-related procedures performed in the Brazilian public health system from 2019 to 2021. Data were retrieved from the Department of Informatics of the Unified Health System (DATASUS). The following procedures were evaluated: fine-needle aspiration biopsies (FNABs), oncologic thyroidectomies, and radioiodine (RAI) therapies for thyroid cancer. The year of 2019 served as baseline control. Results: Compared with 2019, FNABs, oncologic thyroidectomies, and RAI therapies performed in 2020 decreased by 29%, 17% and 28%, respectively. In 2021, compared with 2019, FNABs increased by 2%, and oncologic thyroidectomies and RAI therapies decreased by 5% and 25%, respectively. Most pronounced reductions were observed in the first months of the pandemic. In April 2020, FNABs decreased by 67%, oncologic thyroidectomies by 45%, and RAI therapies by 75%. In 2021, RAI therapies were the only procedure with a statistically significant decrease. Conclusion: The restrictions to public health care during the COVID-19 pandemic resulted in a significant reduction in diagnostic and treatment procedures for thyroid cancer in Brazil. The effects of these transitory gaps in thyroid cancer care, due to COVID-19, are still unclear.

Analysis of factors influencing the clinical outcome after surgery and 131I therapy in patients with moderate-risk thyroid papillary carcinoma.

Purpose: Generally, the prognosis for papillary thyroid cancer (PTC) is favorable. However, the moderate risk involved warrants further evaluation. Hence, we investigated the clinical outcomes in patients with moderate-risk PTC following surgery and the first 131I therapy, as well as the relevant factors that influence the therapeutic efficacy. Methods: Retrospective analyses of 175 patients with medium-risk PTC who visited the Second Affiliated Hospital of Chongqing Medical University from September 2017 to April 2019 were conducted. In according with the 2015 American Thyroid Association (ATA) guideline treatment response evaluation system, the patients were categorized into the following groups: excellent response (ER), indeterminate response (IDR), biochemical incomplete response (BIR), and structurally incomplete response (SIR), of which IDR, BIR, and SIR were collectively referred to as the NER group. To compare the general clinical features between the 2 groups of patients, 2 independent samples t-tests, χ2 test, and Mann-Whitney U-test were performed, followed by multivariate logistic regression analyses. With reference to the receiver operating characteristic (ROC) curve, the predicted value of ps-Tg to ER was evaluated, and the best cut-off value was determined. The subgroups with BRAFV600E test results were analyzed by χ2 test only. Results: The treatment responses of 123 patients were ER, while those of 52 patients were NER. The differences in the maximum tumor diameter (U = 2495.50), the amount of metastatic lymph nodes (U = 2313.50), the size of metastatic lymph node (U = 2113.50), the metastatic lymph node ratio (U = 2111.50), metastatic lymph node location (χ2 = 9.20), and ps-Tg level (U = 1011.00) were statistically significant. Multivariate regression analysis revealed that ps-Tg (OR = 1.209, 95% CI: 1.120-1.305) was an independent variable affecting ER. The cut-off value of ps-Tg for predicting ER was 6.915 ug/L, while its sensitivity and specificity were 69.2% and 89.4%, respectively. Conclusions: Patients with smaller tumor size, fewer lymph nodes, lower metastatic lymph node ratio, metastatic lymph nodes in the central region, smaller lymph node size, and ps-Tg <6.915 ug/L demonstrated better therapeutic effects after the initial treatment.

Effectiveness of mobile robots collecting vital signs and radiation dose rate for patients receiving Iodine-131 radiotherapy: A randomized clinical trial.

Objective: Patients receiving radionuclide 131I treatment expose radiation to others, and there was no clinical trial to verify the effectiveness and safety of mobile robots in radionuclide 131I isolation wards. The objective of this randomized clinical trial was to evaluate the effectiveness and safety of mobile robots in providing vital signs (body temperature and blood pressure) and radiation dose rate monitoring for patients receiving radionuclide therapy. Methods: An open-label, multicenter, paired, randomized clinical trial was performed at three medical centers in Shanghai and Wuhan, China, from 1 April 2018 to 1 September 2018. A total of 72 participants were assigned to the group in which vital signs and radiation doses were both measured by mobile robots and conventional instruments. Intergroup consistency, completion rate, and first success rate were the primary effectiveness measures, and vital sign measurement results, the error rate of use, and subjective satisfaction were secondary indicators. Adverse events related to the robot were used to assess safety. Results: Of the 72 randomized participants (median age, 39.5; 27 [37.5%] male participants), 72 (100.0%) completed the trial. The analysis sets of full analysis set, per-protocol set, and safety analysis set included 72 cases (32 cases in Center A, 16 cases in Center B, and 24 cases in Center C). The consistency, completion rate, and first success rate were 100% (P = 1.00), and the first success rates of vital signs and radiation dose rate were 91.7% (P = 1.000), 100.0% (P = 0.120), and 100.0% (P = 1.000). There was no significant difference in vital signs and radiation dose rate measurement results between the robot measurement group and the control group (P = 0.000, 0.044, and 0.023), and subjective satisfaction in the robot measurement group was 71/72 (98.6%), compared to 67/72 (93.1%) in the control group. For safety evaluation, there was no adverse event related to the mobile robot. Conclusion: The mobile robots have good effectiveness and safety in providing vital signs and radiation dose rate measurement services for patients treated with radionuclides.

Case report: Surgical treatment of McCune-Albright syndrome with hyperthyroidism and retrosternal goiter: A case report and literature review.

Introduction: McCune-Albright syndrome (MAS) is a low-incidence syndrome consisting of the clinical triad of fibrous structural dysplasia of bone, endocrine disease, and skin pigmentation. Thyroid dysfunction is the second most common endocrine dysregulation in MAS. However, there are no treatment guidelines for MAS complicated with hyperthyroidism. Notably, no case of MAS complicated with retrosternal goiter and hyperthyroidism has been reported to our knowledge. Case presentation: We report a 27-year-old man with MAS who developed the typical triad of bone fibrous dysplasia, skin pigmentation and hyperthyroidism, complaining of recent fast-growing neck mass and difficulty in breathing. Hyperthyrodism was under control by Thiamazole, and computed tomography showed an enlarged thyroid extending retrosternally. We performed a total thyroidectomy on the patient. At the 1-year follow-up, the patient's dyspnea, hyperthyroidism, and bone pain were all significantly alleviated. Review: We searched the literature for previous case reports concerning MAS patients complicated with thyroid dysregulation. A total of 17 articles and 22 patients were identified to form our database. Among them, 9 studies clearly mentioned surgical intervention in 11 patients, and prognoses were also reported. Surgery was the most common intervention chosen and indicated a satisfactory prognosis. Conclusion: We report a rare case of MAS patient complicated with retrosternal goiter and hyperthyroidism. Our review provides an overview of MAS cases requiring interventions on thyroid function, and total thyroidectomy should be a proper treatment for these patients.

[Ultrasound combined with Ki67 detection for analyzing contributing factors of failure to cure and recurrence of hyperthyroidism in patients with Graves disease after 131I treatment].

OBJECTIVE: To analyze factors associated with failure to cure or recurrence of hyperthyroidism in patients with Graves disease (GD) after 131I treatment using ultrasound combined with Ki67 detection. METHODS: Eighty-nine patients with GD receiving 131I treatment in the Department of Nuclear Medicine at our hospital from January, 2020 to November, 2021 were enrolled. Before treatment, thyroid volume, shear wave elastic value and Ki67 expression in the follicular epithelial cells were measured using three-dimensional ultrasonic virtual organ computer-aided analysis, shear-wave elastic imaging and ultrasound-guided fine needle aspiration. The data including age, gender, antithyroid drug (ATD) history, dose of 131I, and TRAb were collected from all the cases. The patients were followed up for up to 1 year, starting at 1 month after 131I treatment, and the follow-up results of the patients were divided into failure to cure or recurrence of hyperthyroidism, premature hypothyroidism and euthyroidism or loss to follow-up. The proportional hazards model and fine-Gray test were used to estimate the adjusted hazard ratio (HR) and 95% confidence interval (95% CI) for patients with failure to cure or recurrence of hyperthyroidism. RESULTS: Among the 89 patients, 27 patients were found to have failure to cure or recurrence of hyperthyroidism, 50 had premature hypothyroidism, 1 patient had euthyroidism, and 11 patients were lost to follow-up at the end of the 1-year follow-up. Analysis of the competitive risk model showed that status of Ki67 expression, 131I dose and thyroid volume were independently correlated with failure to cure or recurrence of hyperthyroidism after the treatment with HR (95% CI) of 0.36 (0.15, 0.86), 0.81 (0.68, 0.96) and 1.11 (1.07, 1.15), respectively. CONCLUSION: In patients with GD, the expression of Ki67 in thyroid follicular epithelial cells, 131I dose and thyroid volume are independently correlated with failure to cure or recurrence of hyperthyroidism after 131I treatment. New ultrasound techniques can play an important role in evaluating the therapeutic outcome of 131I treatment in GD patients.

Investigation on the radiation of 131I in treatment site of a grade A tertiary hospital / 中国辐射卫生

Objective To detect the radiation of 131I in treatment site of a grade A tertiary hospital. Methods A total of 25 patients with thyroid cancer were administrated 131I at a total dose of 82880 MBq. After administration, the ambient dose equivalent rate of the ward was detected with X- and γ-ray detectors. After patient discharge, surface contamination of the ward was detected with α/β surface contamination meter. During patient hospitalization and on the day of discharge, air samples were collected from 131I treatment site and office area. The air samples were measured using a HPGe γ-ray spectrometer and the concentration of 131I in air was calculated. Results The ambient dose equivalent rate in the ward ranged from 0.15 to 0.46 μSv/h. Before ward cleaning, surface contamination ranged from 0.53 to 40.1 Bq/cm2 and the highest value was recorded on the toilet. Within 4 h after administration, the concentrations of 131I in air in treatment site and the corridor of the office area were 1.74 Bq/m3 and 0.66 Bq/m3, respectively. The ventilation air flow rate in the treatment site was 0.50 m/s. Ventilation decreased the concentration of 131I in air by 29.7%, 79.7%, and 53.3% compared with the previous day during hospitalization and on the day of discharge. Conclusion The radiation of external exposure of 131I in the treatment site is low and the shielding is effective. Before ward cleaning, the surface contamination is lower than the required limits except for the toilet. Ventilation is the primary way to reduce the concentration of 131I in air.

Feasibility study of predicting dose of radioiodine in hyperthyroidism patients based on neural network / 中华放射医学与防护杂志

Objective:To construct back propagation (BP) neural network model to predict the dose required for 131I therapy for hyperthyroidism and to calculate the personalized dose plan for patients. Methods:A complete set of data of patients treated for hyperthyroidism radioaiodine was collected from the nuclear medicine departments of several medical colleges in Shanghai, including history, examination result, treatment course, etc. As a result, a prediction model was established. The predicated result for BP neural network, radial basis function (RBF) neural network and Support Vector Machine (SVM) were compared by means of small sample data. The optimal model was selected to predict administrated dose and to finally test the accuracy of the model.Results:The average errors in BP neural network, RBF neural network and SVM model based on small samples were 5.53%, 7.09% and 9.64%, respectively. After comparison, BP neural network was selected to build the prediction model. 30 cases of data were selected by random sampling to verify the BP neural network. The mean error, mean square error, minimum error and maximum error of the prediction result were 7.22%, 0.053, 0.57% and 13.78%, respectively.Conclusions:In this study, a neural network prediction method was proposed to provide a more accurate dose for patients in need of radioiodine therap for hyperthyroidism, and to reduce the possibility of radiation damage or the unsatisfactory therapeutic effect caused by insufficient dose. It has clinical practical significance in providing the reference for clinicians to evaluate the administrated dose.

The Influences of TSH Stimulation Level, Stimulated Tg Level and Tg/TSH Ratio on the Therapeutic Effect of 131I Treatment in DTC Patients.

Purpose: To study the influences of pre-ablation TSH stimulation level, sTg and sTg/TSH ratio on the therapeutic effect of the first 131I treatment in DTCs. Methods: According to the thyroid stimulating hormone (TSH) levels (mU/l), all the 479 differentiated thyroid cancer (DTC) patients were divided into two groups: TSH < 30 and TSH ≥ 30. The TSH ≥ 30 group was divided into three subgroups: 30 ≤ TSH < 60, 60 ≤ TSH < 90 and TSH ≥ 90. The clinical features and the therapeutic effects of the first 131I treatment were analyzed. The cutoffs of stimulated thyroglobulin (sTg) and sTg/TSH ratio were calculated to predict the therapeutic effect of 131I treatment. Results: Among the three subgroups, the TSH ≥ 90 subgroup was younger and less likely to be associated with cervical lymph node metastasis (LNM). The postoperative levothyroxine (L-T4) dose in the 60 ≤ TSH < 90 subgroup was the lowest. Between the two groups, patients in the TSH < 30 group had higher postoperative L-T4 dose and longer thyroid hormone withdrawal (THW) time. The excellent response rates six months after the first 131I treatment among the three subgroups and between the two groups were not of statistical significance. The distribution of different TSH stimulation levels among each response group was similar. The cutoffs for the better therapeutic effect of the first 131I treatment in sTg and sTg/TSH were < 9.51 ng/ml and < 0.11, respectively. Both univariate and multivariate logistic regressions showed that cervical LNM, distant metastasis, higher sTg and higher sTg/TSH ratio predicted poorer therapeutic effect. Conclusions: There was no significant influence of TSH stimulation levels before the first 131I treatment on the therapeutic effect of DTC. The sTg/TSH ratio can be considered as another predictor of 131I therapeutic effect.

Clinical Analysis of the Short-Term Outcome of Papillary Thyroid Micro Carcinoma After 131I Treatment.

PURPOSE: To explore the factors that influence the short-term clinical outcome after the first 131I treatment of papillary thyroid micro carcinoma (PTMC). PATIENTS AND METHODS: From October 2015 to June 2018, patients who were diagnosed with PTMC with lymph node metastasis were analyzed retrospectively, excluding patients with incomplete clinical data, distant metastasis, positive TGAb, TSH<30 mIU/L. The baseline data of sex, age, time from last surgery to first 131I treatment, tumor pathology information, and biochemical information were collected before admission. All patients included had radioactive iodine (RAI) with 3.70 GBq. The treatment response of patients was evaluated 6-8 months after discharge. By means of univariate and multivariate analysis, including excellent response (ER) and non-excellent response (NER) groups of clinical data, we assessed the impact of 131I on patients' outcome. A nomogram model was established based on the above independent risk factors. RESULTS: A total of 206 patients (59 males and 147 females, mean age 43.4 ± 10.6 years) were included in the study. The median follow-up time was 169.4 ± 10.5 days, including 139 patients in ER group (67.4%) and 67 patients in NER group (32.5%). Four factors including combining Hashimoto's thyroiditis, pre-ablative Tg levels, UIE levels, and lateral lymph node numbers were statistically different between ER group and NER group with significance at P < 0.05. Further multivariate analysis showed that Hashimoto's thyroiditis and Ps-Tg levels could be used as independent factors. The model verification showed that the C-index of the modeling set was 0.822, indicating that the nomogram model had a good predicted accuracy. CONCLUSION: Our data suggest that coexisting Hashimoto's thyroiditis and elevated Ps-Tg levels are predictive factors for short-term outcome of thyroid micro papillary carcinoma after 131I treatment. Also, the nomogram model had a good predicted accuracy.

Improved Patient Dosimetry at Radioiodine Therapy by Combining the ICRP Compartment Model and the EANM Pre-Therapeutic Standard Procedure for Benign Thyroid Diseases.

Radioactive iodine is commonly used for the treatment of different thyroid conditions since the 1940s. The EANM has developed a standard pre-therapeutic procedure to estimate patient specific thyroid uptake at treatment of benign thyroid diseases. The procedure which models the time dependent fractional thyroid uptake is based on a two-compartment fitting system, one representing the thyroid and the other the blood. The absorbed dose is however only estimated for the thyroid and not for any other organ in the body. A more detailed biokinetic model for iodine is given by the ICRP and includes an iodide transport in the whole body. The ICRP model has 30 different compartments and 48 transfer coefficients to model the biokinetics of iodide and to model different transfer for inorganic iodide and organic iodine. The ICRP model is a recirculation iodine model, and the optimization is performed on the whole model and not exclusively on the thyroid as in the EANM procedure. Combining the EANM method and the ICRP model gives both patient specific estimations of thyroid uptake and retention and include most organs in the body. The new software gives both an improved patient specific dosimetry for the thyroid and an estimation of the absorbed dose to non-target organs and tissues like kidneys, urinary bladder, stomach wall, and uterus. Using the method described in this paper, the repercussions on the daily routines will be minimal.

Monitoring results and analysis of 131I in the air of workplace treated with iodine / 中华放射医学与防护杂志

Objective:To understand the activity concentration of 131I aerosol in the air of the iodine treatment workplace and estimate the internal dose of 131I inhaled by medical staff in nuclear medicine. Methods:Using CF-1001BRL portable large capacity air sampler, the 131I aerosol in the iodine treatment workplace of nuclear medicine department of 6 hospitals in Shandong province was collected by iodine box, and the HPGe-γ energy spectrometer was used to measure the samples. The 131I activity concentration in iodine treatment workplace at 6 hospitals was obtained, and the internal dose to medical staff was estimated. Results:The 131I activity concentration in the air in iodine treatment workplaces at 6 hospitals ranged from 3.64 to 2.94×10 3 Bq/m 3. The 131I activity concentration in the controlled area (ward, patient passageway, subpacking room, operation administration room) was significantly higher than that in the supervised area. The highest 131I activity concentration, 2.62×10 2 Bq/m 3, in the supervised area was found in the medical care passageway. The estimated effective dose to nuclear medicine workers was 0.07-5.68 mSv, not exceeding the national limit. Conclusions:The phenomenon of 131I aerosol contamination still exists in the iodine treatment workplaces of nuclear medicine departments in hospitals, so it is necessary to carry out internal radiation monitoring for nuclear medicine departments all around the country, and explore more reasonable protection standards and methods.

Analysis of external exposure dose during 131I treatment for thyroid cancer patient / 中华放射医学与防护杂志

Objective:To explore the existing issues in radiation protection during the treatment of 131I by means of measuring the ambient dose equivalent rate to patients with thyroid cancer and the dose equivalent to the surface of chest of patients during hospitalization. Methods:The ambient dose equivalent rate (peer) was measured by using gamma ray detector for selected 78 patients who received 131I treatment in a hospital 10 min, 1 d, 2 d, 3 d and 5 d after administration with 131I. The measurements were made at distances of 5 cm, 0.5 m and 1 m from the body surface in front, rear, left and right directions. The photoluminescence dosimeter on the chest of the patients was used to measure the effective dose during hospitalization period (6 d). Results:The ambient dose equivalent rate on the surface of chest of patients was up to 4.81 mSv/h 10 min after administration of medicine. The dose equivalent on the surface of chest of patients before discharge ranged 2.6-64.1 μSv/h. The cumulative dose on chest surface during hospitalization was 15.9-58.8 mGy. There was a significant difference in the dose rate at 5 cm from the body surface between 3.7 GBq group and 5.55 GBq group 10 min after medication ( t=-6.11, P<0.05). There was a significant difference in the dose rate at 5 cm from the body surface between male and female groups 10 min after medication ( t=4.52, P < 0.05). There was no significant difference in other groups ( P > 0.05). Conclusions:During the 131I treatment, patients had high level of radiation around them, so it is necessary to strengthen the protection and management of patients and reduce unnecessary exposure to the public.

Epidemiology, Natural History, Risk Factors, and Prevention of Graves' Orbitopathy.

GO is the most frequent extrathyroidal manifestation of Graves' disease, although it may rarely occur in euthyroid/hypothyroid patients with chronic autoimmune thyroiditis. It is a relatively infrequent disorder, and men tend to have more severe ocular involvement at an older age. The prevalence of GO is lower than in the past among patients with recent onset Graves' hyperthyroidism, and moderate-to-severe forms requiring aggressive treatments are no more than 5-6% of all cases of GO. After an initial inflammatory (active) phase and a phase of stabilization (plateau phase), GO tends to improve and eventually inactivates (inactive or burnt-out phase). Minimal-to-mild GO often remits spontaneously, but complete restitutio ad integrum almost never occurs when GO is more than mild. Several risk factors contribute to its development on a yet undefined genetic background. Cigarette smoking is the most important of them. Early diagnosis, control and removal of modifiable risk factors, early treatment of mild forms of GO may effectively limit the risk of progression to more severe forms, which have a profound and dramatic impact on the quality of life of affected individuals, and remain a therapeutic challenge, often requiring long-lasting and multiple medical and surgical therapies.