Radioactive Iodine Therapy Research Articles

Relationship between pathohistological characteristics of the tumor and distant metastasis of differentiated thyroid cancer

Papillary thyroid cancer has the most favorable prognosis for patients. According to the recommendations of the National Comprehensive Cancer Network (NCCN), organ‑sparing surgery can be performed for such patients without radioactive iodine therapy (RIT). However, some factors, for example, vascular invasion, multifocality, the presence of regional metastases, etc. increase stratification risks for the patient and give the reason to perform more voluminous surgical interventions and conduct RIT. With differentiated thyroid cancer (DTC), the 5‑year and 10‑year overall survival rates reach 100% and 96%, respectively.
 Objective — to investigate the relationship between the pathohistological characteristics of the DTC tumor and distant metastasis.
 Materials and methods. The study involved 522 patients aged 4 to 79 years (the mean age 40.2±0.6 years) after previous thyroid cancer surgery and RIT. Patients were divided into two groups depending on the presence of distant metastases: 28 (5.4%) with distant metastases and 494 (94.6%) patients without distant metastases.
 Results. Using the data of pathohistological findings, both groups were compared according to the following criteria: pathomorphological DTC subtype, vascular invasion, other extraordinary invasion, multifocality, the size of the primary tumor, the size of the largest focus and the total size of foci for multifocal cancers, the number and maximum size of metastases in the central and lateral lymphatic collectors of the neck.
 Conclusions. No significant relationship has been found between the pathomorphological subtype of differentiated thyroid cancer, the presence of vascular and extra‑organ invasion, and the presence of distant metastases, but a relationship was found with multifocality. In the group of patients with distant metastases, a larger size of the primary focus, and a larger size and number of regional metastases were determined.

Abstract 6277: Tall cell variant papillary thyroid carcinoma from Middle Eastern patients have worse outcome than classical papillary thyroid carcinoma using propensity score matching

Abstract The tall cell variant of Papillary Thyroid Carcinoma (TCV-PTC) is the most common aggressive variant of PTC. The impact of TCV-PTC on patients’ prognosis still remains controversial. Moreover, the clinico-pathological and prognostic effect of TCV-PTC from Middle Eastern ethnicity remains unexplored. We aimed to study TCV-PTC in comparison to classical PTC in Middle Eastern patients and their impact on prognosis. We performed a retrospective cohort study of tall cell variant (TCV-PTC) and classic variant of papillary thyroid carcinoma (CV-PTC) after post-surgical radioactive iodine therapy. We used the propensity score matching (1:3 matching ratio) to account for differences between recipients of TCV-PTC vs CV-PTC. Univariate and multivariate analysis were performed to assess the independent factors for persistent/recurrent disease. Kaplan-Meier curve analyses were used to compare disease-free survival (DFS). In total, 174 (16.3%) patients with TCV-PTC and 891 (83.7%) patients with CV-PTC were included. After propensity score matching, 174 pairs of patients were selected (TCV-PTC, n = 174; CV-PTC, n = 522). In the matched analysis, higher proportions of TCV-PTC experienced persistent/recurrent disease compared with CV-PTC (25.7% vs 31.4%; p = 0.0119). In multivariate analyses of clinical and tumor characteristics, histological type of TCV-PTC (odds ratio, 2.09; 95% confidence interval, 1.28-3.40; p = 0.0031) was associated with increased risk of persistent/recurrent disease. The five-year DFS rates for the TCV-PTC and CV-PTC groups were 48.5% and 73.1%, respectively. The Kaplan- Meier analysis indicated that the TCV-PTC group (p < 0.0001) had shorter DFS. In conclusion, when other clinico-pathological factors were similar, this propensity score matched analysis showed that histological subtype TCV-PTC is by itself an independent predictive marker of persistent/recurrent disease in Middle Eastern patients. Therefore, individualized therapeutic approaches might be needed for this aggressive PTC subtype. Citation Format: Khawla S. Al-Kuraya, Sandeep K. Parvathareddy, Abdul K. Siraj, Saeeda O. Ahmed, Nabil Siraj, Manal Manakhan, Hassan Aldossari. Tall cell variant papillary thyroid carcinoma from Middle Eastern patients have worse outcome than classical papillary thyroid carcinoma using propensity score matching [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6277.

GRADE-ADOLOPMENT of hyperthyroidism treatment guidelines for a Pakistani context

IntroductionThe prevalence of hyperthyroidism in Pakistan is 2.9%, which is two times higher than in the United States. Most high-quality hyperthyroidism clinical practice guidelines (CPGs) used internationally originate from high-income countries in the West. Local CPGs in Pakistan are not backed by transparent methodologies. We aimed to produce comprehensive, high-quality CPGs for the management of hyperthyroidism in Pakistan.MethodsWe employed the GRADE-ADOLOPMENT approach utilizing the 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis as the source CPG. Recommendations from the source guideline were either adopted as is, excluded, or adapted according to our local context.ResultsThe source guideline included a total of 124 recommendations, out of which 71 were adopted and 49 were excluded. 4 recommendations were carried forward for adaptation via the ETD process, with modifications being made to 2 of these. The first addressed the need for liver function tests (LFTs) amongst patients experiencing symptoms of hepatotoxicity while being treated with anti-thyroid drugs (ATDs). The second pertained to thyroid status testing post-treatment by radioactive iodine (RAI) therapy for Graves’ Disease (GD). Both adaptations centered around the judicious use of laboratory investigations to reduce costs of hyperthyroidism management.ConclusionOur newly developed hyperthyroidism CPGs for Pakistan contain two context-specific modifications that prioritize patients’ finances during the course of hyperthyroidism management and to limit the overuse of laboratory testing in a resource-constrained setting. Future research must investigate the cost-effectiveness and risk-benefit ratio of these modified recommendations.

Standard therapy or additionally radioactive iodine (131I) therapy; which will stop the recurrence of glioblastoma multiforme (GBM)?

Glioblastoma multiforme (GBM) is the most aggressive malignant brain tumour. The average survival time for a patient diagnosed with GBM, using standard treatment methods, is several months. Authors of the article pose a direct question: Is it possible to treat GBM solely with radioactive iodine (¹³¹I) therapy without employing the sodium iodide symporter (NIS) gene? After all, NIS has been detected not only in the thyroid but also in various tumours. The main author of this article (A.C.), with the assistance of her colleagues (physicians and pharmacologists), underwent ¹³¹I therapy after prior iodine inhibition, resulting in approximately 30% reduction in tumour size as revealed by magnetic resonance imaging (MRI). Classical therapy for GBM encompasses neurosurgery, conventional radiotherapy, and chemotherapy (e.g. temozolomide). Currently, tyrosine kinase inhibitors (imatinib, sunitinib, and sorafenib) are being used. Additionally, novel drugs such as crizotinib, entrectinib, or larotrectinib are being applied. Recently, personalised multimodal immunotherapy (IMI) based on anti-tumour vaccines derived from oncolytic viruses has been developed, concomitant with the advancement of cellular and molecular immunology. Thus, ¹³¹I therapy has been successfully employed for the first time in the case of GBM recurrence.

Presentation and treatment of two cases of malignant struma ovarii

BackgroundMalignant Struma Ovarii (MSO) is a rare type of germ cell tumour which is diagnosed postoperatively on surgical pathology specimens by the presence of differentiated thyroid cancer in mature cystic teratomas in the ovaries. Treatment and follow-up procedures are not clearly established due to the paucity of MSO cases.Case 1A 44-year-old multiparous female presented with an irregular period. Ultrasound showed a left ovarian lesion mostly a dermoid cyst, however, CT showed a 3.8 × 2.7 × 4 cm complex cystic lesion with thick septation and enhancing soft tissue component. Laparoscopic left salpingo-oophorectomy was performed and histopathology showed a follicular variant of papillary thyroid carcinoma arising in a mature cystic teratoma. Peritoneal cytology was positive for malignancy. A thyroid function test was normal before surgery. Total thyroidectomy was performed followed by radioactive (RAI) iodine therapy. Later, a total laparoscopic hysterectomy and right salpingo-oophorectomy were performed. There is no evidence of recurrent disease during the 26-months follow-up.Case 2A 46-year-old single female presented with left lower abdominal pain that had persisted for 2 months. Imaging revealed an 8 × 9 × 9.5 cm left ovarian mass. Laparoscopic left salpingo-oophorectomy was performed and histopathology showed mature cystic teratoma with small papillary thyroid cancer. CT showed no evidence of metastatic disease. Later, the patient had a total thyroidectomy followed by radioactive (RAI) iodine therapy. She was started on thyroxine and later had total abdominal hysterectomy and right salpingo-oophorectomy.ConclusionMSO is a very rare tumour. Preoperative diagnosis is very difficult because of the nonspecific symptoms and the lack of specific features in imaging studies. Also, there is no consensus on the optimal treatment of women with MSO. Our two cases add to the limited number of MSO cases.

Clinical Outcomes and Implications of Radioactive Iodine Therapy on Cancer-specific Survival in WHO Classification of FTC.

The clinical outcomes and implications of radioactive iodine therapy (RAIT) on cancer-specific survival (CSS) in World Health Organization classification of follicular thyroid carcinoma (FTC) are not well established. The data of eligible patients with minimally invasive FTC (mi-FTC), encapsulated angioinvasive FTC (ea-FTC), or widely invasive FTC (wi-FTC) between 2000 and 2020 were extracted from the Surveillance, Epidemiology, and End Results database. CSS, the primary outcome, was compared among the 3 subtypes of patients with FTC before and after adjusting for differences using propensity score matching (PSM). The patients with FTC in different subtypes were then divided into 2 groups: the RAIT group and the no-RAIT group. Cox proportional hazards regression analyses were applied to discover the relationships of factors associated with CSS in the each PSM cohort. A total of 2433 patients with mi-FTC, 216 patients with ea-FTC, and 554 patients with wi-FTC were enrolled in the original cohorts, respectively. Patients with mi-FTC or ea-FTC had similar CSS (P = .805), which was better than that of patients with wi-FTC (P < .001; P = .021). Cox proportional hazards regression analysis revealed that RAIT was not associated with improved CSS in either the mi-FTC PSM cohort (hazard ratio [HR], 1.21; 95% CI, .46-3.18; P = .705) or the wi-FTC PSM cohort (HR, 0.56; 95% CI, .35-1.08; P = .086). However, subgroup analysis demonstrated that patients with wi-FTC and N1 stage (HR, 0.44; 95% CI, .20-.99; P = .018) or M1 stage (HR, 0.25; 95% CI, .11-.53; P < .001) could gain CSS advantage from RAIT. The RAIT can provide a CSS advantage for patients with wi-FTC who with N1-stage or M1-stage disease.

Radioiodine ablation after thyroidectomy could be safely abandoned or postponed in selected stage I papillary thyroid carcinoma patients of low-risk group: an observational prospective study

Background. The European Thyroid Association consensus for the management of differentiated thyroid cancer (2006) suggested to avoid radioactive iodine (RAI) after thyroidectomy in patients with unifocal microcarcinoma (≤ 1 cm) with no extension beyond the thyroid capsule and without lymph node metastases. As the new data was collected and the risk stratification was revised, in 2022 the same recommendation was expanded to the patients with microcarcinoma and central neck lymph node involvement. The American Thyroid Association guidelines (2015) advocated no RAI ablation after hemi- or total thyroidectomy for thyroid cancer less than 1 cm with 5 and less micrometastases up to 2 mm in central neck lymph nodes as this strategy has no negative impact on the disease prognosis. In low-risk patients, no sufficient evidence of the obligatory postsurgical radioiodine ablation has been yet demonstrated. The aim of our study was to reveal whether RAI after thyroidectomy can be abandoned or postponed until the disease progression is confirmed in low-risk patients. Materials and methods. Two groups of patients (30 per group, 60 in total) with papillary microcarcinoma Т1N1a (5 and less level VI micrometastases up to 2 mm) were observed during a 5-year follow-up. In the first group, patients received 100 mCi (3.75 GBq) I131 shortly after total thyroidectomy while in the second group, postponed RAI was applied when progression signs were observed (elevated serum thyroglobulin level and US/CT suspected findings) after thyroid surgery. Results. After 5 years, no significant difference between groups was observed regarding post-RAI local recurrences (one in the first group and two in the second group) and/or distant metastases (t-test, p = 0.58). All cases of neck recurrences were treated with subsequent surgical excision, with no new data of progression within the specified follow-up. Conclusions. RAI adjuvant therapy for papillary thyroid carcinoma Т1N1a may not be necessary for patients with small number of level VI micrometastases. Local and distant metastases revealed during the careful follow-up by thyroglobulin level elevation and when using visualization techniques can be effectively treated with postponed RAI therapy and/or surgery.

Comparable Remission Rates for ATA Low-Risk Pediatric Thyroid Cancer Patients Treated and Those Not Treated with Radioactive Iodine Therapy

Comparable Remission Rates for ATA Low-Risk Pediatric Thyroid Cancer Patients Treated and Those Not Treated with Radioactive Iodine Therapy

Topical Application of Perchlorate: A Toxicity Study in Rats.

To investigate the ocular safety profile of topical perchlorate as a potential preventive treatment for nasolacrimal obstruction associated with excessive use of radioactive iodine therapy. Nine Wistar male rats (18 eyes) were randomly assigned to receive an ocular application (topical eye drop on the OD, 3 times a day for 5 days) consisting of either: 1) sterile saline solution, 2) 30 mg/ml NaClO4 or 3) 30 mg/ml KClO4. The rat eyes were examined daily for corneal cloudiness/clarity, discharge, mucous secretions, conjunctival injection, eyelid erythema, and/or changes in behavior. Seven days after the first dose, the rats were euthanized and OU were harvested, fixed, embedded in paraffin, and stained with H&E and Masson's trichrome using standard techniques. The data collected over the 7 days revealed no behavior changes or ocular complications in any of the 3 study groups. Pathologic analysis of the corneas revealed normal findings on all groups without signs of inflammation, fibrosis, or any other abnormality, and no difference between the treated and control eyes. The findings of this study suggest that the use of topical perchlorate is safe to use on eyes in high concentrations. The efficacy of this compound in minimizing fibrosis of the nasolacrimal sac and duct warrants further study.

Follicular Thyroid Carcinoma with Unusual Mandible Metastasis.

Follicular thyroid cancer is the second-most common type of thyroid cancer after papillary thyroid cancer. Metastases to the mandible and maxillofacial region are rare. Our study presents a 55-year-old patient who underwent total thyroidectomy for follicular thyroid cancer and subsequent radioactive iodine therapy. Sixteen years after diagnosis, elevated thyroglobulin levels suggested disease recurrence. Using advanced imaging techniques - Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography scan, bone scintigraphy, and posttreatment I-131 scan-an unexpected metastatic site was identified: the left mandibular condyle. A biopsy confirmed the presence of metastatic follicular thyroid cancer.

Nursing Guidelines on Safety Measures Awareness among Patients with Thyroid Disorders undergoing Radioactive Iodine Therapy

Nursing Guidelines on Safety Measures Awareness among Patients with Thyroid Disorders undergoing Radioactive Iodine Therapy

Indolent Behavior of Malignant Bethesda III Nodules Compared to Bethesda V/VI Nodules.

The Bethesda system classifies all fine-needle aspiration specimens into 1 of 6 categories. We speculated that cancers within each Bethesda category would have distinct clinical behavior. This is a retrospective analysis of patients from a single academic medical center with a histologic diagnosis of thyroid cancer who had an initial diagnosis of Bethesda III, IV, V, or VI cytology. A total of 556 cases were included, with 87 cases of Bethesda III, 109 cases of IV, 120 cases of V, and 240 cases of VI. Bethesda III showed similarities with V/VI compared to IV with a predominance of papillary thyroid cancer. The interval from diagnosis to surgery was longer in Bethesda III compared to Bethesda V/VI (median 78 vs 41 days, P < .001) (Fig. 1). Yet, patients with Bethesda III had a higher probability of achieving remission (62% vs 46%, P < .03), a lower possibility of recurrence (8% vs 24%, P < .001), and a shorter interval to achieve remission (median 1218 vs 1682 days, P = .02) compared to Bethesda V/VI, which did not change after adjusting for age, sex, radioactive iodine therapy, mode of surgery, and tumor size. More than 70% of Bethesda III that later presented with recurrence had T3/T4 disease or distant metastasis. Cancers with Bethesda III cytology had a less aggressive clinical phenotype with better prognosis compared to V/VI despite histological similarities. The time to remission was shorter in Bethesda III despite a longer interval between diagnosis and surgery. The initial cytological diagnosis may guide management.

Utility and optimal management of planned drug holidays during lenvatinib treatment in patients with unresectable differentiated thyroid cancer: a real-world multi-center study.

Lenvatinib achieves favorable therapeutic outcomes for patients with radioactive iodine therapy refractory differentiated thyroid cancer (DTC); however, its use is associated with a high incidence of adverse events. To avoid severe adverse events, planned drug holidays (PDH) have been proposed. This study aimed to evaluate treatment effects, identify prognostic factors, and investigate the usefulness of PDH in patients with unresectable DTC who received lenvatinib across the multi-institutions. Fifty-one patients with unresectable DTC treated with lenvatinib were evaluated retrospectively. Overall survival (OS) and progression-free survival (PFS) were calculated, and prognostic factors were assessed. OS, PFS, and time to treatment failure (TTF) were compared between patients with and without PDH. Lenvatinib administration schedule was evaluated in PDH. The 3-year OS and PFS rate were 53.5% and 42.1%, respectively. Multivariate analysis revealed that presence of maximum size of lung metastasis ≥10 mm was independent prognostic factor for poorer OS and PFS, and histology other than papillary thyroid carcinoma was the independent prognostic factor for poorer PFS. Twenty-five patients (49%) treated with PDH. There were significant differences in OS, PFS, and TTF between patients with and without PDH. Various schedules were used in PDH. Eight (32%) patients required switch to the different administration schedule. Our results suggest that PDHs may extend OS, PFS, and TTF. In patients with PDH, various schedules used for lenvatinib administration highlight the difficulty in determining a uniform administration schedule. Therefore, it is crucial to consider the optimal lenvatinib administration schedule on a case-by-case basis.

Thyroidectomy Effects on the Body Mass Index and Thyroid-Stimulating Hormone: A Systematic Review and Meta-Analysis.

Thyroidectomy is common and is performed for malignancy, goiters with pressure symptoms, and certain types of Grave's disease. Weight and body mass index (BMI) following thyroidectomy were discussed controversially. This meta-analysis aimed to assess weight and BMI following thyroidectomy. A systematic literature search was conducted in PubMed, Medline, and Google Scholar with interest in articles that assessed body weight and BMI following total or subtotal thyroidectomy. The search engine was limited to the period from inception up to January 2024. Keywords "total thyroidectomy", "subtotal thyroidectomy", "Graves' disease", "multinodular goiter", "differentiated thyroid carcinoma", and "toxic nodules" were used. Out of the 634 articles retrieved, 89 full texts were screened, and only six studies (five retrospective and one prospective cohort) fulfilled the inclusion and exclusion criteria. No differences were evident regarding weight and BMI before and after thyroidectomy (odds ratio: -0.63, 95%CI: -1.50 to -0.24, P-value for the overall effect: 0.15; and odds ratio: -0.12, 95% CI: -0.41 to -0.16, P-value for the overall effect: 0.40 respectively). No heterogeneity was observed (I2 for heterogeneity: 0.0%). No association between thyroidectomy (when performed for differentiated thyroid carcinoma and hyperthyroidism), weight, and BMI was found. Further studies assessing thyroid-stimulating hormone (TSH) levels, radioactive iodine therapy, and thyroxine dose are needed.

Shortened telomere length in peripheral blood leukocytes is associated with cumulative radioactive iodine doses in patients with differentiated thyroid carcinoma.

Telomere length is associated with cancer risk and cancer aggressiveness. Radioactive iodine (RAI) therapy for thyroid cancer has raised concerns for second primary malignancy (SPM) in patients with high cumulative doses. The association between RAI dose and peripheral blood leukocyte telomere length was examined. A total of 425 patients were included who underwent total thyroidectomy and were followed up for at least 1year with or without RAI treatment. The relative telomere length (RTL) of the patients was assessed via a quantitative polymerase chain reaction amplification method. RAI doses were divided into five groups on the basis of cumulative dose, and a comparison was made among these groups. The number of patients with RAI treatment was 287 (67.5%), and the cumulative RAI dose was 3.33GBq (range, 1.11-131.35 GBq). The mean RTL was significantly shorter in the highest RAI group (>22.2GBq) compared to both the no-RAI and lower dose groups. The association between RAI dose and RTL was positive in the lower RAI group (1.1-3.7GBq) and negative in the highest RAI group in both univariate and multivariate analyses. We observed 59 (13.9%) SPMs and 20 (4.7%) mortalities, and RTL did not show a significant risk effect for all-cause, thyroid cancer-specific, or SPM-specific mortality. In patients with thyroid cancer who underwent total thyroidectomy, peripheral blood leukocyte telomere length exhibited a significant association with cumulative RAI dose higher than 22.2GBq. These results suggest the possibility of telomere length shortening in patients who undergo high-dose RAI treatment.

The effect of COVID-19 pandemic restrictions on the management of differentiated thyroid cancer in Turkey: a single tertiary centre experience.

Many countries have implemented unprecedented health measures since the World Health Organisation declared the novel coronavirus disease 2019 (COVID-19) a global pandemic. These measures have resulted in delays in the diagnosis of differentiated thyroid cancer (DTC). However, there is limited data on the impact of restrictions imposed during the pandemic on DTC management. Thus, the aim of this study is to analyse the clinicopathological and follow-up data of DTC patients diagnosed before and during the COVID-19 outbreak. This retrospective study included 191 DTC patients that were diagnosed between December 2018 and June 2021. The patients were divided into two groups: patients diagnosed before (December 2018 to February 2020) and during (March 2020 to June 2021) the COVID-19 pandemic. The clinicopathological and follow-up data between the two groups were compared. Similar preoperative cytology results were obtained from the two groups. No difference with regard to tumour size, lymphovascular invasion and extrathyroidal invasion was observed between the two groups. While the American Thyroid Association risk stratification was similar between the two groups, radioactive iodine (RAI) therapy was applied less during the COVID-19 period. Although RAI therapy was administered at a lower rate during the COVID-19 period, the recurrence rates among patients after two years of follow-up were similar to those during the pre-COVID-19 period. Although the COVID-19 pandemic restrictions during the pandemic period caused difficulties in the management of DTC patients, this did not negatively affect their prognosis. These findings can confirm the applicability of active surveillance in DTC patients and may help change the real-life treatment practices in selected low-risk DTC patients.

Absorbed dose coefficients for pediatric differentiated thyroid cancer patients undergoing radioiodine therapy

The escalating incidence of differentiated thyroid cancer (DTC) in pediatric patients and the resultant growing use of radioactive iodine (RAI) reinforce the need to evaluate radiation exposure to normal tissues and radiation-induced health risks in pediatric patients undergoing RAI therapy. In the current study, we calculated absorbed dose coefficients (i.e. absorbed dose per unit activity administered, mGy MBq−1) specific for pediatric patients with localized DTC undergoing RAI therapy following total thyroidectomy for use in epidemiological studies. We first modified previously-published biokinetic models for adult thyroid cancer patients to achieve a reasonable agreement with iodine biokinetics observed in pediatric patients or design principles addressed in the International Commission on Radiological Protection (ICRP) reference age-specific biokinetic models. We then combined the biokinetic models in conjunction with S values derived from ICRP reference pediatric voxel phantoms. The absorbed dose coefficients for pediatric patients were overall greater than those for adults with a ratio (pediatric/adult) up to 11.6 and rapidly decreased with increasing age. The sensitivity analysis showed that the renal clearance rate and S values may have the greatest impact on the absorbed dose coefficients with the rank correlation coefficients ranging from −0.53 to −0.82 (negative correlations) and from 0.51 to 0.80 (positive correlations), respectively. The results of the current study may be utilized in clinical or epidemiological studies to estimate organ-specific radiation absorbed doses and radiation-associated health risks among pediatric thyroid cancer patients.

Molecular Imaging and Therapy of Differentiated Thyroid Carcinoma in Adults.

Differentiated thyroid carcinoma (DTC) has been increasing in incidence in the United States over the last several decades, although mortality rates have remained low. Radioactive iodine therapy (RAI-T) has been a mainstay of treatment for DTC since the 1940s. Imaging of DTC before and after RAI-T primarily focuses on molecular imaging of the sodium iodide symporter. The expanding understanding of the molecular profile of DTC has increased available treatment options. Incorporation of risk stratification to treatment approaches has led to deintensification of both surgical and nonsurgical treatments, leading to decreased morbidity without compromising disease control.

Radioactive Iodine Therapy of Graves’ Disease in Patients Pretreated With Methimazole Without Radioiodine Uptake for Dose Estimation

ObjectiveTo assess response predictors to radioactive iodine (RAI) therapy without using thyroid uptake for dose estimate in patients pretreated with methimazole. MethodsRetrospective analysis was performed of patients with Graves’ disease treated with RAI doses determined without using uptake studies. ResultsIn 242 patients (median age, 41.9 years; 66.1% female), initial mean free thyroxine (FT4) level was 4.7 ng/dL with an estimated thyroid size of 49.15 g. Prior to RAI therapy, average methimazole dose was 22.7 mg/day. Mean RAI dose was 737.0 ±199.4 MBq (19.9 ± 5.4 mCi). Two hundred eight patients (85.9%) responded to RAI therapy; 185 (88.9%) became hypothyroid and 23 (11.1%) became euthyroid. The majority (90.4%) responded within 6 months of therapy with a quicker response (13.9 ± 8.3 vs 17.5 ± 13.5 weeks) for those treated with doses per gram of ≥14.8 MBq (0.4 mCi). Thirty-four nonresponders had a higher initial FT4 level and larger thyroid size with a lower RAI dose per gram of thyroid tissue. In multivariate analysis, the independent response predictor to therapy was dose per gram of thyroid tissue of ≥14.8 MBq (0.4 mCi) (hazard ratio, 3.18; 95% CI, 1.1-9.7). Doses per gram of 14.8 to 18.1 MBq (0.4-0.5 mCi) achieved maximal response rate without added advantage of higher doses. Thyroid size prior to RAI therapy, FT4 levels at diagnosis, and age were inversely related to response. ConclusionRAI therapy for Graves’ disease without uptake studies for dose estimates is an effective treatment method. In patients pretreated with methimazole, an RAI dose per gram of thyroid tissue of ≥14.8 MBq (0.4 mCi) showed high response rate. Prospective studies are needed to confirm the viability of this simplified and cost-effective approach.

New Case of Papillary Thyroglossal Tract Cyst Carcinoma, in the Absence of Clear Guidelines, What Should Be Do?

Thyroglossal tract cyst carcinoma (TTCC) is a rare pathological situation, The challenge is mainly in the surgical management. In this article, we report a new case of papillary TTCC in a 51 years old female patient, not suspected preoperatively and confirmed postoperatively by histological analysis of the resected specimen. The therapeutic strategy was completed by a total thyroidectomy with adjuvant treatment with radioactive iodine and hormone restraint therapy. The outcome was favorable after 7 years of follow-up. In the absence of clear guidelines, the management of TTCC depends on the clinical situation and the experience of the treating team.