Radioactive iodine administration is not associated with improved disease-specific survival in classic papillary thyroid carcinoma greater than 4 cm confined to the thyroid.

BACKGROUND: We aimed to evaluate the impact of radioactive iodine on disease-specific survival in intrathyroidal (N0M0) papillary thyroid carcinoma >4 cm, given conflicting data in the American Thyroid Association guidelines regarding their management. METHODS: The Surveillance, Epidemiology, and End Results database was queried for N0M0 classic papillary thyroid carcinoma >4 cm. Kaplan-Meier estimates were performed to compare disease-specific survival between radioactive iodine-treated and untreated groups. A multivariable Cox regression was performed to identify predictors of disease-specific survival. RESULTS: There were more patients aged ≥55 (41.7% vs 32.3%, P = .001) and fewer multifocal tumors (25.3% vs 30.6%, P = .006) in the no radioactive iodine group. Ten-year disease-specific survival was similar between the radioactive iodine treated and untreated groups (97.2% vs 95.6%, P = .34). Radioactive iodine was not associated with a significant disease-specific survival benefit (adjusted hazard ratio = 0.78, confidence interval [0.39-1.58], P = .49). Age ≥55 (adjusted hazard ratio = 3.50, confidence interval [1.69-7.26], P = .001) and larger tumor size (adjusted hazard ratio = 1.04, confidence interval [1.02-1.06], P < .001) were associated with an increased risk of disease-specific death. Subgroup analyses did not demonstrate improved disease-specific survival with radioactive iodine in patients ≥55 and in tumors >5 cm. CONCLUSION: Adjuvant radioactive iodine administration in classic papillary thyroid carcinoma >4 cm confined to the thyroid did not significantly impact disease-specific survival. Thus, these patients may not require routine treatment with adjuvant radioactive iodine.

Early Structural, Biochemical, and Metabolic Responses to Anlotinib in Patients With Progressive Radioactive Iodine Refractory Differentiated Thyroid Cancer.

OBJECTIVE: We aimed to assess the early efficacy of anlotinib in patients with progressive radioactive iodine refractory differentiated thyroid cancer at the structural, biochemical, and metabolic levels. METHODS: Ten eligible patients were prospectively enrolled to receive anlotinib. Their responses were assessed at 6 weeks. Apart from the structural response according to Response Evaluation Criteria in Solid Tumors version 1.1, the biochemical response was assessed by serum thyroglobulin (Tg), and the metabolic response was assessed by 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) according to the European Organization for Research and Treatment of Cancer criteria. A safety profile was recorded. RESULTS: Structurally controlled disease (20% partial response + 80% stable disease) was observed in all patients. The median longest diameter of target lesions shrank from 20.8 mm (IQR, 14.9-27.5) to 17.0 mm (IQR, 14.1-23.7) (P < .001), and the average shrinkage rate was -15.1 ± 14.1%. Sharp serum Tg reduction by 72.8 ± 16.4% was observed in 8 measurable patients. The 18F-FDG PET/CT-mapped glucose metabolic response was not quite comparable to the structural response, with 90% of the patients having controlled disease (30% partial metabolic response + 60% stable metabolic disease), whereas 10% presented progressive metabolic disease. The most common treatment-emergent adverse events (AEs) were hypertension (100%) and proteinuria (70%). Most AEs were grade 1 or 2, whereas grade 3 AEs occurred only in hypertension. CONCLUSION: Anlotinib is generally well tolerated and can bring early disease control within the initial 6 weeks of treatment. The sharp biochemical response suggests Tg to be an early sensitive biomarker to anlotinib, whereas the heterogeneous metabolic response might play a complementary role.

Effects of postoperative antioxidants on the salivary glands in patients with thyroid cancer undergoing radioactive iodine-131 treatment.

OBJECTIVE: This study aimed to evaluate the effects of three antioxidants, selenium yeast capsule, vitamin E and vitamin C, alone or in combination, on the salivary glands of patients with differentiated thyroid cancer (DTC) treated with iodine-131 ( 131 I). METHODS: A total of 69 postoperative DTC patients were randomly divided into three groups: vitamin E combined with vitamin C group (21 cases); selenium yeast group (23 cases); and selenium yeast combined with vitamin C group (25 cases). Salivary gland functional changes were assessed by salivary gland dynamic imaging functional parameters in the enrolled patients before and 1 month after 131 I treatment. RESULTS: Comparison of salivary gland function parameters before and after 131 I treatment in the three groups were evaluated. In the vitamin E combined with the vitamin C group, the left parotid gland excretion fraction (EF) value was significantly higher than that before treatment. In the selenium yeast group, the left parotid gland excretion part, bilateral parotid gland excretion ratio (ER), left submandibular gland maximum uptake ratio within 20 min (UR20), and the right submandibular gland ER values were significantly higher than that before treatment, while in the selenium yeast combined with vitamin C group, the bilateral parotid gland EF, bilateral submandibular gland UR20, EF, and left submandibular gland ER values were significantly higher than that before treatment (all P < 0.05). CONCLUSION: During high-dose 131 I treatment, vitamin E combined with vitamin C improved the excretory function of parotid glands in DTC patients; selenium supplementation had a protective effect on salivary glands; and the combination of selenium and vitamin C had a better effect.

Diffuse Bone Uptake of 131 I and Effect on Blood Counts in a Patient With Papillary Thyroid Carcinoma and Chronic Lymphocytic Leukemia.

ABSTRACT: A 57-year-old woman with history of chronic lymphocytic leukemia was referred to our center for adjuvant 131 I therapy following complete thyroidectomy for differentiated thyroid cancer. Posttherapeutic scintigraphy revealed atypical diffuse osteomedullar uptake. A major drop in lymphocyte count was observed, from 117.7 g/L to 4.8 g/L 8 weeks after 131 I therapy. Bone marrow uptake is presumed to be related to tracer sequestration in leukemic cells. White blood cell count normalization suggests a high sensitivity of leukemic cells to beta emission. This scintigraphic pattern may act as a pitfall for nuclear medicine physician.

A rare case of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer: Case report and review of the literature.

BACKGROUND: Thyroid carcinosarcoma represents a rare subtype of thyroid cancer, distinguished by its unique histopathology-simultaneous malignant epithelial and mesenchymal cells. The occurrence of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer is exceptionally infrequent. METHODS: Study outlines a patient's thyroid carcinosarcoma journey, covering presentation, recurrence, diagnostics, surgeries, and follow-up. A PubMed search gathered data on pathological features and treatment approaches for thyroid carcinosarcoma. RESULTS: The patient initially diagnosed with papillary thyroid cancer underwent thyroidectomy, neck dissection, and radioactive iodine therapy. Recurrence revealed thyroid carcinosarcoma, featuring papillary carcinoma, squamous cell carcinoma, and spindle cell components. Total laryngectomy followed by adjuvant radiotherapy and chemotherapy. The patient was followed for 17 months with no evidence of disease. CONCLUSIONS: This extraordinary case exemplifies a rare instance of local relapse in form of thyroid carcinosarcoma following an initial diagnosis of papillary thyroid carcinoma. Surgical resection and chemoradiotherapy show promising outcomes in managing this challenging condition.

Retrospective case-control study examining the relationship between recurrence-free survival and changes in pre- and post-radioiodine therapy serum thyroglobulin levels in patients with differentiated thyroid cancer.

PURPOSE: Thyroglobulin assay is important to assess the residual or recurrence of differentiated thyroid cancer (DTC). Patients with positive serum thyroglobulin levels after radioactive iodine (RAI) adjuvant therapy could achieve long-term recurrence-free survival (RFS). The patient's prognosis could not be confidently estimated based solely on the evaluation of thyroglobulin levels. We investigated the recurrence rate and RFS of patients who received adjuvant RAI therapy after surgery for DTC to clarify the relationship between changes in pre- and post-therapy serum thyroglobulin levels and RFS. MATERIALS AND METHODS: Patients who underwent adjuvant RAI therapy between May 2007 and March 2021 were included in this study, whereas those with positive anti-thyroglobulin antibodies, distant metastases, or gross residual tumors were excluded. The change in pre- and post-treatment serum thyroglobulin levels under thyroid-stimulating hormone stimulation was calculated and classified as follows: group A, thyroglobulin levels decreased by ˃10%; group B, thyroglobulin levels within a range of 10% or less; and group C, thyroglobulin levels increased by ˃10%. RFS outcomes were analyzed using the Kaplan-Meier method. Univariate analysis was performed using the log-rank test, and multivariate analysis was performed using the Cox proportional hazard model. RESULTS: A total of 74 patients were included. Relapse was seen in 13 of 46 patients in group A, 9 of 15 in group B, and 10 of 13 in group C. Median RFS was 129.00 (95% confidence interval CI 77.79-180.21), 113.00 (95% CI 86.83-139.17), and 33 months (95% CI 6.026-59.974) in groups A, B, and C, respectively. Patients in group C exhibited significantly shorter RFS than those in groups A and B (P = 0.001). CONCLUSIONS: Changes in thyroglobulin levels pre- and post-therapy were associated with RFS. Patients with decreased post-therapy thyroglobulin levels had a favorable prognosis, even if their thyroglobulin levels were positive after RAI therapy.

Correlation between remnant thyroid gland I-131 uptake and serum thyroglobulin levels: can we rely on I-131 whole body scans?

BACKGROUND: I-131 treatment (RAI) decision relies heavily on serum thyroglobulin (Tg) levels, as higher Tg levels are assumed to be correlated with higher I-131 uptake. Tg elevation, negative iodine scintigraphy (TENIS) definition is becoming more clinically relevant as alternative treatment methods are available. This study examined the correlation between Tg levels with I-131 uptake in remnant thyroid gland to evaluate the reliability of serum Tg levels in predicting I-131 uptake. METHODS: From March 2012 to July 2019, 281 papillary thyroid cancer patients treated with 150 mCi RAI were retrospectively enrolled. Early (2nd day) and Delayed (7th day) post-RAI whole-body scan (WBS) neck counts were correlated with clinical and pathologic findings. Patients with normal neck ultrasound and undetectable level of serum Tg (< 0.2 ng/mL) and thyroglobulin antibody (TgAb) (< 10 IU/mL) were defined as ablation success within 2 years after I-131 ablation. RESULTS: Thyroid gland weight, tumor size and thyroiditis were independent factors of preoperative serum Tg levels. Serum off-Tg levels correlated with Early and Delayed WBS neck counts, and thyroiditis pathology contributed to lower neck counts in both Early and Delayed WBSs. In multivariable analysis, Delayed WBS neck count, serum off-Tg and off-TgAb were significant factors for predicting ablation success. CONCLUSION: I-131 uptake and retention in remnant thyroid gland correlates with serum off-Tg levels, thyroiditis, and ablation success in thyroid cancer patients receiving high-dose I-131 therapy. Semi-quantitative I-131 analysis with Early and Delayed WBSs provides additional information in evaluating ablation success, with the potential application for metastasis treatment response evaluation.

Cabozantinib for different endocrine tumours: killing two birds with one stone. A systematic review of the literature.

PURPOSE: Cabozantinib is an oral multi-tyrosine kinase inhibitor (TKI) that has been approved in Europe for advanced renal cell carcinoma, hepatocellular carcinoma, locally advanced and metastatic medullary thyroid carcinoma (MTC) and radioiodine-refractory differentiated thyroid cancer. Merkel cell carcinoma (MCC) is a rare and highly aggressive cutaneous malignant neuroendocrine tumour that usually presents in sun-exposed skin areas of immunosuppressed patients. Conflicting data exist about cabozantinib for MCC and this TKI is currently under investigation in several onco-endocrine frameworks. METHODS: We herein report a case of an 83-year-old man who was diagnosed with MCC during the treatment of an advanced metastatic MTC. The diagnosis of MCC was established based on clinical, histopathologic evaluation and immunohistochemistry. A systematic review of the literature on cabozantinib use for advanced endocrine and neuroendocrine tumours has been performed. RESULTS: The patient was initially treated with surgery and adjuvant radiotherapy. Cabozantinib was therefore started to control both MTC and MCC. After 24 months, no sign of local or metastatic MCC relapse was evidenced. CONCLUSION: Promising data on cabozantinib treatment for endocrine and neuroendocrine neoplasms is recently emerging in the literature. In our clinical case, we reported that, besides the good response for the MTC, cabozantinib also seems to effectively control metastatic MCC, along with efficient surgery and adjuvant radiotherapy. Further investigations are needed to determine the efficacy and safety of cabozantinib in MCC patients and in off-label endocrine tumours.

Effect of Radioactive Iodine Therapy on Cancer-Specific Survival of Papillary Thyroid Cancer Tall Cell Variant.

CONTEXT: Radioactive iodine (RAI) therapy is often used as an adjuvant treatment to reduce the risk of recurrence in patients with papillary thyroid cancer (PTC). However, the effect of RAI therapy on cancer-specific survival (CSS) in patients with tall cell variant (TCV) remains controversial. OBJECTIVE: This study aimed to investigate the impact of RAI therapy on CSS in patients with TCV-PTC by analyzing data from the Surveillance, Epidemiology, and End Results database. METHODS: We identified 1281 patients with TCV-PTC in the SEER database who underwent total thyroidectomy between 2004 and 2019. Of these, 866 (67.6%) patients received RAI therapy and 415 (32.4%) did not. Propensity score matching was conducted to balance the baseline characteristics between the 2 groups. Cox proportional hazards regression models were used to estimate the hazard ratio (HR) and 95% CI for the effect of RAI therapy on CSS. RESULTS: After propensity score matching, 373 pairs of patients were included in the analysis. The results showed no significant difference in CSS between the RAI therapy group and the non-RAI therapy group (HR 0.54, 95% CI 0.25-1.17, P = .120). Subgroup analyses indicated similar results. CONCLUSION: RAI therapy may not improve CSS in patients with TCV-PTC after total thyroidectomy. Future studies with larger sample sizes, longer follow-up periods, and better study designs are needed to confirm or refine our research findings.

Clinical Outcomes of Radioactive Iodine Redifferentiation Therapy in Previously Iodine Refractory Differentiated Thyroid Cancers.

Objective: Redifferentiation therapy (RDT) can restore radioactive iodine (RAI) uptake in differentiated thyroid cancer (DTC) cells to enable salvage 131I therapy for previously RAI refractory (RAIR) disease. This study evaluated the clinical outcomes of patients who underwent RDT and identified clinicopathologic characteristics predictive of RAI restoration following RDT. Methods: This is a retrospective case series of 33 patients with response evaluation criteria in solid tumors (RECIST)-progressive metastatic RAIR-DTC who underwent RDT between 2017 and 2022 at the Mayo Clinic (Rochester, MN). All patients underwent genomic profiling and received MEK, RET or ALK inhibitors alone, or combination BRAF-MEK inhibitors for 4 weeks. At week 3, those with increased RAI avidity in metastatic foci received high-dose 131I therapy. Baseline and clinicopathologic outcomes were comprehensively reviewed. Results: Of the 33 patients, 57.6% had restored RAI uptake following RDT (Redifferentiated subgroup). 42.1% (8/19) with papillary thyroid cancers (PTC), 100% (4/4) with invasive encapsulated follicular variant PTCs (IEFV-PTCs), and 100% (7/7) with follicular thyroid cancers (FTC) redifferentiated. All (11/11) RAS mutant tumors redifferentiated compared with 38.9% (7/18) with BRAF mutant disease (6 PTC and 1 IEFV-PTC). 76.5% (13/17) of redifferentiated and 66.7% (8/12) of non-redifferentiated patients achieved a best overall RECIST response of stable disease (SD) or non-complete response/non-progressive disease. Both subgroups had a median 12% tumor shrinkage at 3 weeks on drug(s) alone. The redifferentiated subgroup, following high-dose 131I therapy, achieved an additional median 20% tumor reduction at 6 months after RDT. There were no statistically significant differences between both groups in progression free survival (PFS), time to initiation of systemic therapy, and time to any additional therapy. Of the entire cohort, 6.1% (2/33) experienced histologic transformation to anaplastic thyroid cancer, 15.1% (5/33) died, and all had redifferentiated following RDT and received 131I therapy. Conclusion: RDT has the potential to restore RAI avidity and induce RECIST responses following 131I therapy in select patients with RAIR-DTC, particularly those with RAS-driven "follicular" phenotypes. In patients with PTC, none of the evaluated clinical outcomes differed statistically between the redifferentiated and non-redifferentiated subgroups. Further studies are needed to better characterize the long-term survival and/or safety outcomes of high-dose RAI following RDT, particularly whether it could be associated with histologic anaplastic transformation.

One-year Thyroglobulin Levels as a Predictive Measure for Recurrence and Need for Continued Surveillance in Treated Differentiated Thyroid Cancer.

PURPOSE: Patients with differentiated thyroid cancer (DTC) undergo posttreatment surveillance for several years. We aim to better define an excellent response to therapy using thyroglobulin (TG) and thyroglobulin antibody (TGab) levels at 1-year to tailor appropriate length of surveillance. METHODS: Patients with DTC who underwent surgical treatment with or without adjuvant radioiodine therapy were followed with standard American Thyroid Association surveillance. TG and TGab levels at 1-year posttreatment were used to define 3 cohorts: undetectable TG (<0.5 ng/mL), detectable TG (≥0.5 ng/mL), and positive TGab (>1 IU/mL). The rates of structural recurrence and the trends of TG and TGab were compared. RESULTS: Of the 268 study patients at 1-year, 210 (78%) had undetectable TG, 29 (11%) had detectable TG, and 29 (11%) had positive TGab. The overall structural recurrence rate was 18/268 (7%): undetectable TG at 1 year, 3/210 (1%), detectable TG at 1-year, 11/29 (38%), and positive TGab at 1-year, 4/29 (13%). At the last follow-up, 196/210 (93%) patients with undetectable TG at 1-year continued to have undetectable TG levels. Regarding patients with detectable TG at 1-year, in 11/29 (38%), detectable TG was converted to undetectable TG at the last follow-up without additional treatments. Of those with positive TGab at 1 year, 6/29 (21%) had resolution of TGab and undetectable TG levels at the last follow-up without additional treatments. CONCLUSION: One year after treatment of DTC, TG levels <0.5 ng/mL, in the absence of TGab, are associated with an exceedingly low risk of recurrence suggesting that further surveillance may not be warranted.

Management of aggressive variants of papillary thyroid cancer.

PURPOSE OF REVIEW: The aim of this study was to provide a timely and relevant review of the latest findings and explore appropriate management of aggressive variants of papillary thyroid cancer (AVPTC). RECENT FINDINGS: In general, AVPTCs tend to exhibit more invasive characteristics, a lack of responsiveness to radioiodine, increased occurrences of regional spreading, distant metastases and higher mortality rates. Meanwhile, each variant showcases unique clinical and molecular profiles. SUMMARY: Given the elevated risk of recurrence postsurgery, a more aggressive strategy may be necessary when suspected preoperatively, particularly for those presenting with invasive features. Decision on the extent of surgical treatment and adjuvant therapy is individualized and made by experienced clinicians and multidisciplinary teams based on the clinical presentation, presence of aggressive features and molecular profile. Future studies on development of personalized medicine and molecular target therapy may offer tailored treatment options.

Adjuvant treatments for locally advanced differentiated thyroid cancer: a nationwide survey in Japan.

The role of adjuvant external-beam radiotherapy (EBRT) for locally advanced differentiated thyroid cancer (DTC) is controversial because of the lack of prospective data. To prepare for a clinical trial, this study investigated the current clinical practice of adjuvant treatments for locally advanced DTC. A survey on treatment selection criteria for hypothetical locally advanced DTC was administered to representative thyroid surgeons of facilities participating in the Japan Clinical Oncology Group Radiation Therapy Study Group. Of the 43 invited facilities, surgeons from 39 (91%) completed the survey. For R1 resection or suspected residual disease, 26 (67%) facilities administered high-dose (100-200 mCi) radioactive iodine (RAI), but none performed EBRT. For R2 resection or unresectable primary disease, 26 (67%) facilities administered high-dose RAI and 7 (18%) performed adjuvant treatments, including EBRT. For complete resection with nodal extra-capsular extension, 13 (34%) facilities administered high-dose RAI and 1 (3%) performed EBRT. For unresectable mediastinal lymph node metastasis, 31 (79%) facilities administered high-dose RAI and 5 (13%) performed adjuvant treatments, including EBRT. Adjuvant EBRT was not routinely performed mainly because of the lack of evidence for efficacy (74%). Approximately 15% of the facilities routinely considered adjuvant EBRT for DTC with R2 resection or unresectable primary or lymph node metastasis disease. Future clinical trials will need to optimize EBRT for these patients.

Sustained Response with Dose-reduced Selpercatinib in a Pediatric Patient with Metastatic NCOA4-RET Fusion Papillary Thyroid Carcinoma.

Understanding the molecular landscape of papillary thyroid carcinoma (PTC), the most common thyroid cancer in children, creates additional therapeutic approaches. RET gene rearrangements are observed in pediatric PTC, and selective inhibition of RET is now possible with specific tyrosine kinase inhibitors designed to target diverse RET -activating alterations. We present a 13-year-old female with metastatic PTC, clinically resistant to radioactive iodine, and found to harbor a NCOA4-RET fusion. She responded to selpercatinib treatment with the elimination of supplemental oxygen need, marked reduction in pulmonary nodules and mediastinal lymphadenopathy, and biomarker decline. The response was maintained despite 2 dose reductions for possibly related weight gain.

Recurrence-free survival and prognosis after adjuvant therapy with radioactive iodine-131 in patients with differentiated thyroid carcinoma.

This study aimed to assess recurrence-free survival (RFS) rates and recurrence-related factors of patients who received adjuvant therapy (AT) with radioactive iodine (RAI) for differentiated thyroid cancer (DTC) following thyroidectomy. We evaluated 284 patients who underwent AT between January 2011 and July 2020 at our hospital. Recurrence was defined as visible recurrent lesions on image analysis or need for repeat surgery with pathologically confirmed recurrent lesions. RFS rate and prognostic factors were statistically evaluated. The median observation period was 30.2 months (range, 5.7-294 months). Overall, 192 patients were female and 92 were male, and the median age was 54 years (range, 9-85 years). Initial assessment revealed 39 recurrence cases. The 3-year RFS rate was 85.8% (95% confidence interval: 81.1-90.9%). Univariate analysis revealed that histology (except for papillary carcinoma), Tg level > 4 ng/dL before AT, and AT result significantly exacerbated the RFS rate. In multivariate analysis, histology and AT result were also important contributors to the worsening RFS rate. Results of AT can be determined relatively early and are important in predicting future recurrence in patients with DTC. Increasing the success rate of AT may lead to an improved prognosis.

Advances in the molecular mechanism and targeted therapy of radioactive-iodine refractory differentiated thyroid cancer.

Most patients with differentiated thyroid cancer have a good prognosis after radioactive iodine-131 treatment, but there are still a small number of patients who are not sensitive to radioiodine treatment and may subsequently show disease progression. Therefore, radioactive-iodine refractory differentiated thyroid cancer treated with radioiodine usually shows reduced radioiodine uptake. Thus, when sodium iodine symporter expression, basolateral membrane localization and recycling degradation are abnormal, radioactive-iodine refractory differentiated thyroid cancer may occur. In recent years, with the deepening of research into the pathogenesis of this disease, an increasing number of molecules have become or are expected to become therapeutic targets. The application of corresponding inhibitors or combined treatment regimens for different molecular targets may be effective for patients with advanced radioactive-iodine refractory differentiated thyroid cancer. Currently, some targeted drugs that can improve the progression-free survival of patients with radioactive-iodine refractory differentiated thyroid cancer, such as sorafenib and lenvatinib, have been approved by the FDA for the treatment of radioactive-iodine refractory differentiated thyroid cancer. However, due to the adverse reactions and drug resistance caused by some targeted drugs, their application is limited. In response to targeted drug resistance and high rates of adverse reactions, research into new treatment combinations is being carried out; in addition to kinase inhibitor therapy, gene therapy and rutin-assisted iodine-131 therapy for radioactive-iodine refractory thyroid cancer have also made some progress. Thus, this article mainly focuses on sodium iodide symporter changes leading to the main molecular mechanisms in radioactive-iodine refractory differentiated thyroid cancer, some targeted drug resistance mechanisms and promising new treatments.

[The features of regulatory T-blood cells subpopulation and the level of CD25 expression in patients with Graves' disease in dynamics after radioactive iodine therapy].

BACKGROUND: The content of regulatory T cells (Treg) at different stages in formation of effector subpopulations and the level of CD25 expression on the membrane of their various fractions in Graves' disease can determine the long-term autoimmune process persistence and be the target of immunotropic therapy of the disease. AIM: To study the features of regulatory T-blood cells subpopulation and the level of CD25 expression in patients with Graves' disease in dynamics after radioactive iodine therapy (RIT) to identify the specific Treg subpopulations for potential immunotropic therapy targets of the disease. MATERIALS AND METHODS: A single-center, prospective, cohort, open, controlled study was conducted with the participation of women with laboratory-confirmed Graves' disease. The features of regulatory T-blood cells subpopulation and the level of expression (MFI) CD25 surface receptor were studied by flow cytometry using direct immunofluorescence using monoclonal antibodies. RESULTS: The study included 36 women with recurrent Graves' disease, middle age 46.34±14.32 years. In patients with Graves' disease before and during the entire period after RIT a low percentage of naive (CD45R0-CD62L+) and terminally differentiated (CD45R0-CD62L-) Treg was established relative to the control, and on 3 and 6 months after RIT a significant decrease of cells with this phenotype was revealed relative to the values detected in patients before and 1 month after RIT (p<0.001). Against the background of compensated hypothyroidism the most significant changes of expression CD25 receptor in patients with Graves' disease were found on 3 and 6 months after RIT: reduced levels of MFI CD25 on surface of naive and terminally differentiated Treg. CONCLUSION: A decrease in the level of naive Treg was found (apparently due to a violation of differentiation processes in thymus) and terminally differentiated Tregs (due to maturation and survival processes), which are supplemented by a reduced expression of the CD25 receptor on the surface of these cells and do not depend on hyperthyroidism compensation, the titer of TSH receptor antibodies, previous conservative therapy with thiamazole and RIT. The obtained new data reveal the role of naive and terminally differentiated Treg subpopulations in immunopathogenesis and help to outline further ways to develop approaches for immunotropic therapy.

Update on iodine-refractory differentiated thyroid carcinoma.

Radioiodine therapy represents a fundamental pillar in the routine adjuvant therapy of patients with high-risk differentiated thyroid carcinoma. However, a non-negligible percentage of these patients will develop iodine refractoriness, showing a worse prognosis, as well a lower survival, which demonstrates a clear need to explore different therapeutic approaches. Iodine refractory patient treatment continues to be a challenge, currently having different novel therapeutic options that should be known by the different specialties related to differentiated thyroid carcinoma (DTC). The aim of this work is to review iodine refractory thyroid carcinoma treatment, focusing especially on the definition of iodine refractoriness, highlighting its importance due to its high mortality, and introducing the different therapeutic options available for these patients.

Utility of adjuvant radioactive iodine therapy after reoperation in papillary thyroid carcinoma with cervical lymph node recurrence.

PURPOSE: The aim of this study was to evaluate the utility of RAI therapy after reoperation for patients with LN relapse. MATERIALS AND METHODS: We retrospectively evaluated PTC patients who had undergone reoperation due to cervical LN recurrence. We used the chi-square test, Fisher's exact test, Student's t test and the Mann-Whitney U test to compare characteristics between patients retreated with RAI and those who did not receive RAI after reoperation. A multivariate logistic regression model was used to determine the association between RAI and biochemical response. By means of the Kaplan-Meier estimator and a multivariate Cox proportional hazard model, we assessed whether administration of RAI after reoperation is associated with improved prognosis. RESULTS: RAI therapy was closely associated with a superior biochemical response in all selected patients according to both univariate (p = 0.012) and multivariate analyses (p = 0.020). Thirteen of 97 patients developed a second recurrence or progression of structural disease during follow-up. A Kaplan-Meier progression-free survival (PFS) curve showed that high post-retreatment thyroglobulin (Tg) levels (≥ 1 ng/mL) were associated with unfavourable prognosis (p = 0.0172). In the subgroup analysis, univariate analysis revealed that only patients without extranodal invasion who received adjuvant RAI therapy achieved better PFS than those who did not receive RAI therapy (p = 0.0203). Multivariate analysis showed that RAI (p = 0.045) also improved PFS in patients without extranodal invasion. CONCLUSIONS: Adjuvant RAI after reoperation for PTC recurrence/persistence was associated with a favourable biochemical response and tended to increase PFS. Specifically, it was significantly associated with improved PFS only in patients without extranodal extension.

Radioactive iodine in the management of medullary carcinoma of the thyroid.

OBJECTIVES: Although it is generally accepted that medullary thyroid cancer (MTC) cells do not take up iodine, there are reports indicating that this can occur. Additionally, the potential for radioactive iodine (RAI) to reduce the risk of recurrence within the thyroid bed following thyroid remnant ablation in MTC is uncertain. A systematic review was therefore undertaken. METHODS: Studies of patients with MTC of any age or stage receiving RAI, either as adjuvant postoperative treatment or primary treatment for unresectable disease, or as treatment for recurrent or metastatic disease were eligible for inclusion. Randomised and non-randomised studies were identified by electronic searching of Medline and Embase databases. A risk of bias assessment (ROBINS-I) was carried out for each study. Outcome measures sought included overall survival, locoregional relapse-free survival, rates of locoregional recurrence, and changes in serum calcitonin. A protocol was registered with PROSPERO before the systematic review was undertaken. RESULTS: There were no randomised studies. Ten non-randomised studies (525 patients) and ten case reports (21 patients) met the inclusion criteria, with all studies containing a high risk of bias. There were case reports reporting responses to RAI, both as adjuvant treatment and for recurrent/metastatic disease. CONCLUSIONS: The proportion of metastatic or recurrent MTC which take up iodine remains unknown. A possible role of RAI ablation for patients with localised MTC and raised calcitonin post-thyroidectomy should be explored. ADVANCES IN KNOWLEDGE: Although there is insufficient data to recommend changes to current treatment policies, this review suggests avenues for further research.