131I Treatment Research Articles

Risk of Infertility in Reproductive-Age Patients With Thyroid Cancer Receiving or Not Receiving 131I Treatment

Background Fertility is the crucial concern for many survivors of cancer diagnosed as children, adolescents, and young adults. The objective of this study was to determine the risk of infertility in reproductive-age patients with thyroid cancer receiving or not receiving radioiodine treatment in Taiwan. Methods This nationwide population-based cohort study was conducted using data obtained from the Taiwan National Health Insurance Database from 2009 to 2019. A total of 20,259 thyroid cancer patients aged from 15 to 50 years (8037 did not receive 131I treatment, and 12,222 received 131I treatment) and 20,259 controls were enrolled. A Cox proportional hazards model was applied to estimate the risk of infertility in thyroid cancer patients receiving or not receiving 131I treatment in terms of hazard ratios and 95% confidence intervals. Results The incidence rates of infertility in thyroid cancer receiving 131I therapy, those not receiving 131I therapy, and controls were 5.55, 5.07, and 3.61 per 1000 person-years, respectively. Compared with thyroid cancer patients treated with a cumulative 131I dose of 4.44 GBq or less, the risk of infertility was not significantly increased in those treated with a cumulative 131I dose of more than 4.44 GBq (adjusted hazard ratio, 1.13; 95% confidence interval, 0.95–1.36). Conclusion The greatest increased risk of infertility in reproductive-age patients with thyroid cancer is associated with the fact that the patient has thyroid cancer regardless of 131I administration. 131I treatment or cumulative dose of 131I greater than 4.44 GBq did not further increase the risk of infertility.

A digital pathology model for predicting radioiodine-avid metastases on initial post-therapeutic 131I scan in patients with papillary thyroid cancer.

Accurate postoperative assessment is critical for optimizing 131I therapy in patients with papillary thyroid cancer (PTC). This study aimed to develop a pathology model utilizing postoperative digital pathology slides to predict lymph node and/or distant metastases on post-therapeutic 131I scan after initial 131I treatment in PTC patients. A retrospective analysis was conducted on 229 PTC patients who underwent total or near-total thyroidectomy and subsequent 131I treatment after levothyroxine (LT4) withdrawal between January 2022 and August 2023. The pathology model was developed through two stages: patch-level prediction and WSI-level prediction. The clinical model was constructed using statistically significant variables identified from univariate and multivariate logistic regression analysis. Of the 229 patients, 19.6% (45/229) exhibited 131I-avid metastatic foci in post-therapeutic 131I scan. Multifactorial analysis identified stimulated thyroglobulin (sTg) as the sole independent risk factor. The AUC of the pathology model in the training and test cohorts were 0.976 (95% CI 0.948-1.000) and 0.805 (95% CI 0.660-0.951), respectively, which were significantly higher than the clinical model (AUC 0.652 and 0.548, Pall < 0.05). This model has the potential to serve as a valuable tool for clinicians in tailoring treatment strategies, thereby optimizing therapeutic outcomes for PTC patients.

8390 It's not Cancer: Establishing the Diagnosis of Hyaline Trabecular Tumor

Abstract Disclosure: R.A. Zielinski: None. M. Khalifa: None. M. Dillon: None. M. Kaur: None. Background: Hyaline trabecular tumor (HTT) is a rare benign follicular thyroid neoplasm characterized by extensive intra-trabecular hyaline stromal material. Resemblances to other follicular neoplasms create difficulty in distinguishing HTT from its more nefarious counterparts such as medullary thyroid cancer (MTC) and papillary thyroid cancer (PTC).Clinical Case:Our patient is a 56-year-old female with Hashimoto’s thyroiditis diagnosed in her twenties who has been on different strengths of levothyroxine based on her fluctuating TSH. A thyroid ultrasound done to evaluate left-sided neck fullness on physical exam showed a solid, hypoechoic 2.3 cm x 1.4 x 0.9 cm left middle thyroid nodule without calcifications (TI-RADS 4) and benign-appearing lymph nodes, the largest of which was 1.5 cm at level 1B. Cytology from a thyroid FNA biopsy was suspicious for PTC, Bethesda category IV. A thyrosure genetic panel was negative for genetic mutations. FNA biopsy of the 1.5 cm lymph node was negative for malignancy. The patient was referred for thyroid lobectomy but instead elected to undergo total thyroidectomy with level VI lymph node dissection. Pathology revealed a 2.2 cm HTT in the left lobe, scattered psammoma bodies in adjacent soft tissue, and a 0.2 cm multifocal papillary microcarcinoma in the right lobe. The microcarcinoma had negative margins, no lymphatic or vascular invasion, and 7/7 benign level VI lymph nodes; staging it as pT1aN0. Immunohistochemistry staining was positive for TTF-1 and thyroglobulin and negative for calcitonin, chromogranin, and synaptophysin. Post-thyroidectomy she was started on Tirosint 175 mcg daily with good response. No I-131 treatment was pursued due to the microcarcinoma being categorized as low risk.Discussion and Conclusion: HTT is a benign neoplasm and management is usually conservative with surgical excision. The diagnosis of HTT by cytology alone is challenging due to the presence of nuclear clearing, grooves and intranuclear pseudo-inclusions that may be mistaken for PTC or MTC. Cell membrane immunoreactivity of MIB1 monoclonal to Ki67 and the molecular identification of the novel PAX8-GLIS1 or PAX8-GLIS3 fusions may aid in making the correct diagnosis.

7466 The Effects Of Various Forms Of Diabetes On Features Of Tumor Aggressiveness In Thyroid Cancer

Abstract Disclosure: R.D. Paparodis: None. E. Karvounis: None. A. Kapezanou: None. S. Livadas: None. G. Simeakis: None. D.P. Askitis: None. I. Androulakis: None. N.G. Angelopoulos: None. D. Zianni: None. A. Rizoulis: None. A. Boniakos: None. I. Perogamvros: None. D. Bantouna: None. J.C. Jaume: None. Introduction: Diabetes has been linked to increased risk for several cancers and aggressiveness of tumor behavior. A link between thyroid cancer and diabetes appears controversial in the literature as of yet. We designed the present study to assess whether autoimmune (type 1 + LADA = DM1) or type 2 diabetes (DM2) are associated with more aggressive thyroid cancers compared to those found in non-diabetic (non-DM) individuals. Methods: We retrospectively reviewed data from patients undergoing thyroid surgery in 10 Endocrinology and Endocrine Surgery Clinics throughout Greece over 2 years. We collected data on history and type of diabetes, pre-existing to the thyroid surgery, its treatments and duration, the preoperative thyroid function tests and the surgical pathology findings. We compared the incidence of various histological types of thyroid cancer and the features of tumor aggressiveness between patients with diabetes and those with normal glucose homeostasis (non-DM) (DM1 vs. DM2 vs. non-DM). Results: Overall, n=808 subjects with thyroid cancer were included: n=571 were females (70.7%), age 47.3 ± 14.3 years, BMI 27.0 ± 5.0 Kg/m2, mean TSH 1.99 ± 2.21 mIU/L; n= 692 were non-DM, n=10 had DM1 and n=107 had DM2. Histology revealed n=5 poorly differentiated / anaplastic, n=13 medullary, n=12 Hürthle cell, n=17 follicular and n=773 papillary thyroid cancers (PTC); n=20 (2.5%) with aggressive histological subtypes of PTC, n=5 (0.6%) with distant metastases (MET), n=199 (24.6%) with extrathyroidal extension (ETE), n=419 (51.9%) with capsular invasion (CI), n=225 (27.8%) with lymph nodes involvement (LNi) and n=23 with cancer recurrence (CR) (2.8%). The incidence of aggressive histological types, CR, MET or number of I-131 treatments were not different between groups (p&amp;gt;0.05). ETE, CI and LNi were significantly more common in non-DM compared to both diabetes groups, while gross ETE was more common in DM2 over DM1 and non-DM (p&amp;lt;0.001). Conclusions: More DM1 than DM2 seem to confer a protective effect on several features of cancer aggressiveness in affected individuals. On the other hand, more DM2 than DM1 seems to significantly promote gross ETE. No effect was observed pertaining to the risk for more aggressive tumors or histological subtypes of PTC. Although aggressiveness of thyroid cancer seems controlled in DM1 and to a lesser degree in DM2 the complex interplay between autoimmunity, hyperglycemia and thyroid cancer biology requires larger sample size to better determine causative effects. Presentation: 6/2/2024

7466 The Effects of Various Forms of Diabetes on Features of Tumor Aggressiveness in Thyroid Cancer

Abstract Disclosure: R.D. Paparodis: None. E. Karvounis: None. A. Kapezanou: None. S. Livadas: None. G. Simeakis: None. D.P. Askitis: None. I. Androulakis: None. N.G. Angelopoulos: None. D. Zianni: None. A. Rizoulis: None. A. Boniakos: None. I. Perogamvros: None. D. Bantouna: None. J.C. Jaume: None. Introduction: Diabetes has been linked to increased risk for several cancers and aggressiveness of tumor behavior. A link between thyroid cancer and diabetes appears controversial in the literature as of yet. We designed the present study to assess whether autoimmune (type 1 + LADA = DM1) or type 2 diabetes (DM2) are associated with more aggressive thyroid cancers compared to those found in non-diabetic (non-DM) individuals. Methods: We retrospectively reviewed data from patients undergoing thyroid surgery in 10 Endocrinology and Endocrine Surgery Clinics throughout Greece over 2 years. We collected data on history and type of diabetes, pre-existing to the thyroid surgery, its treatments and duration, the preoperative thyroid function tests and the surgical pathology findings. We compared the incidence of various histological types of thyroid cancer and the features of tumor aggressiveness between patients with diabetes and those with normal glucose homeostasis (non-DM) (DM1 vs. DM2 vs. non-DM). Results: Overall, n=808 subjects with thyroid cancer were included: n=571 were females (70.7%), age 47.3 ± 14.3 years, BMI 27.0 ± 5.0 Kg/m[2], mean TSH 1.99 ± 2.21 mIU/L; n= 692 were non-DM, n=10 had DM1 and n=107 had DM2. Histology revealed n=5 poorly differentiated / anaplastic, n=13 medullary, n=12 Hürthle cell, n=17 follicular and n=773 papillary thyroid cancers (PTC); n=20 (2.5%) with aggressive histological subtypes of PTC, n=5 (0.6%) with distant metastases (MET), n=199 (24.6%) with extrathyroidal extension (ETE), n=419 (51.9%) with capsular invasion (CI), n=225 (27.8%) with lymph nodes involvement (LNi) and n=23 with cancer recurrence (CR) (2.8%). The incidence of aggressive histological types, CR, MET or number of I-131 treatments were not different between groups (p&amp;gt;0.05). ETE, CI and LNi were significantly more common in non-DM compared to both diabetes groups, while gross ETE was more common in DM2 over DM1 and non-DM (p&amp;lt;0.001). Conclusions: More DM1 than DM2 seem to confer a protective effect on several features of cancer aggressiveness in affected individuals. On the other hand, more DM2 than DM1 seems to significantly promote gross ETE. No effect was observed pertaining to the risk for more aggressive tumors or histological subtypes of PTC. Although aggressiveness of thyroid cancer seems controlled in DM1 and to a lesser degree in DM2 the complex interplay between autoimmunity, hyperglycemia and thyroid cancer biology requires larger sample size to better determine causative effects. Presentation: 6/2/2024

7911 High Dose Serial Radioactive Iodine Therapies Facilitated byAutologous Stem Cell Cryopreservation in a Patient with Exceptionally Avid Metastatic FTC

Abstract Disclosure: S. Paknikar: None. D. Toro Tobon: None. J. Durski: None. H. Alkhateeb: None. M.M. Ryder: None. Introduction: Radioactive iodine (RAI) therapy-induced myelosuppression is a dose-limiting toxicity for RAI avid metastatic differentiated thyroid cancers. We describe a patient with exceptionally RAI avid metastatic follicular thyroid cancer (FTC) who underwent autologous stem cell cryopreservation (ASCC) to enable high dose I-131 treatments. Case: A 60-year-old woman with T1bN0M0 FTC underwent two-stage thyroidectomy and three doses of I-131 between 2002-2007 (434 mCi cumulative activity) due to incomplete biochemical response. She presented to our institution in 2015 with rising thyroglobulin (Tg) levels and lung nodules that were intensely RAI avid. She enrolled in a clinical trial of selumetinib versus placebo (for 1 month) followed by 150 mci I-131. She had a profound response with an 80% reduction in Tg and 50% tumor shrinkage. The following year her Tg rose to 8381 ng/mL and she developed biopsy proven, well differentiated metastatic FTC in the hip and liver. Lenvatinib treatment resulted in partial tumor and Tg response but was halted due to grade 3/4 toxicities. Tumor genomic interrogation revealed NRAS, PIK3CA, and TSH-R activating mutations, providing a causal explanation of her intensely RAI avid and responsive disease. Repeat I-131 therapy was facilitated by GM-CSF stimulated ASCC (8.57 x10(6) CD34+ cells/kg for two cycles) as a tool to help mitigate future potential RAI-induced myelosuppression. The patient received 295 mci I-131 followed by a 98% decrease in Tg and 20-25% shrinkage of liver metastases. Transient pancytopenia ensued but did not require autologous stem cell transplantation (ASCT). Due to insurance issues, the patient was lost to follow-up for two years. She returned with cachexia from severe, untreated thyrotoxicosis due to widespread functional, thyroxine producing metastatic disease. Anti-thyroid drug therapy (ATD) restored euthyroid status with significant clinical improvement. A non-stimulated I-123 whole body scan showed diffuse RAI avid disease with 88% whole body radioiodine retention at 48h. She received 125 mci I-131 with initial tumor response but with progression of bone marrow, calvaria, and retinal metastases. Six months later, a final dose of 253 mCi I-131 (cumulative activity 1,370 mCi) resulted in mixed tumor responses. Unfortunately, resection of a RAI refractory calvaria lesion postoperatively resulted in serious complications. ASCT and salvage treatments could not be pursued due to her impaired functional status. The patient pursued hospice care and passed away 20 years after her diagnosis. Conclusion: We characterize a patient with NRAS, PIK3CA and TSH-R mutant metastatic, thyroxine-producing FTC whose recurrences over 20 years retained intense RAI avidity and response to I-131 therapy. In cases with potential benefit from multiple high dose RAI therapies, ASCT may be a tool to mitigate I-131-induced myelosuppression. Presentation: 6/1/2024

Risk factors and distribution pattern of lateral lymph node recurrence after central neck dissection for cN1a papillary thyroid carcinoma

BackgroundThe indication and extent of selective lateral neck dissection (LND) for cN1a papillary thyroid carcinoma (PTC) remain uncertain. The present study aimed to identify potential predictors and distribution pattern of lateral lymph node recurrence (LLNR) after central neck dissection in cN1a PTC patients.MethodsThe cN1a PTC patients who underwent initial central neck dissection at our centre were retrospectively reviewed, and the median follow-up period was 6.8 years. Reoperation with LND was performed when LLNR was confirmed. Risk factors for LLNR were identified, and the metastatic status of each lateral level was recorded.ResultsOf the 310 patients enrolled in the present study, fifty-eight patients (18.7%) presented with LLNR. Six independent factors, including tumour diameter, pathological T4 stage, number of involved central lymph nodes, pTNM stage, extrathyroidal extension, and I131 treatment (P values < 0.05) were identified via multivariate analysis. LLNR was found at level II in 26 patients (44.8%), level III in 38 patients (65.5%), level IV in 30 patients (51.7%), and level V in 8 patients (13.8%). The number of positive lateral lymph nodes at levels II, III, IV and V was 44 (22.9%), 76 (39.6%), 63 (32.8%), and 9 (4.9%), respectively.ConclusionsFor cN1a PTC patients who underwent central neck dissection, tumour diameter ≥ 2 cm, pathological T4 stage, number of involved central lymph nodes ≥ 3, pTNM stage III-IV, extrathyroidal extension, and failure to receive I131 treatment were independent predictors of LLNR, which was more likely to occur at levels III and IV.

Is second 131I treatment necessary for differentiated thyroid cancer patients and who could not benefit from it? A real-world retrospective study in China.

The efficacy of a second radioactive iodine-131 (131I) treatment in patients with differentiated thyroid cancer (DTC) who did not achieve an excellent response (ER) following initial 131I therapy remains controversy and the population that would derive limited benefit from it is currently unclear. The aim of this retrospective study was to assess the efficacy of the second 131I treatment in DTC patients with non-ER after the initial 131I therapy, and to identify potential risk factors associated with non-benefit of the second 131I treatment. 127 DTC patients who underwent two 131I treatments following thyroidectomy were included in this study, and the therapeutic response was evaluated after each 131I treatment. Beneficial treatment was defined as an improvement in therapy response grade (e.g. from indeterminate response to ER) after the second 131I treatment, while unbeneficial treatment was defined as no change or a downgrade in therapy response grade. The potential risk factors associated with the non-benefit of the second 131I treatment were identified using univariate and multivariate logistic regression models. Following the second 131I treatment, therapy responses of 55.12% (70/127) of patients were reclassified to a better grade indicating treatment benefit, while 44.88% (57/127) showed no change or were reclassified to a worse grade suggesting no benefit from treatment. The non-benefit of the second 131I treatment was significantly associated with potential risk factors including stimulated thyroglobulin (sTg) level ≥ 11.46ng/mL before the second 131I treatment, primary tumor size > 2cm, status T2 or higher, N1b status and ATA high risk. The study results demonstrated that more than half of DTC patients could potentially benefit from a second 131I therapy. However, over 40% of patients exhibited no benefit in response to the second 131I treatment, suggesting potential overtreatment for this subgroup. Therefore, clinicians should exercise meticulous and precise decision-making based on identified risk factors when considering the necessity of a second 131I treatment.

Long-Term Outcome of Patients with Low-Risk Differentiated Thyroid Cancer Treated with Total Thyroidectomy Alone.

Differentiated thyroid carcinoma (DTC), mainly papillary (PTC), at low risk of recurrence is currently managed with active surveillance strategies or less aggressive surgeries. However, total thyroidectomy with 131I treatment is still performed both if these tumors are diagnosed before or occasionally after surgery. This real-life study aimed to evaluate the rate of biochemical, structural, and functional events in a large series of consecutive DTCs at low risk of recurrence treated by total thyroidectomy, but not with 131I, in a medium-long-term follow-up. We evaluated clinical-pathologic data of 383 consecutive patients (2006-2012) with unifocal DTC [T1a/b(s)] at low risk of recurrence, treated with total thyroidectomy but without lymph node dissection and 131I treatment after surgery. We evaluated if structural, biochemical, and functional events were detected during the follow-up. Females accounted for 75.7% of our study group, and the median age was 50 years. The median tumor dimension was 0.4 cm (range 0.1-1.2). Most of the patients had a unifocal T1a tumor (98.9%), and 73.6% had a classic variant of PTC. We divided the patients according to the absence (group A-n = 276) or presence (group B-n = 107) of interfering TgAb at first control after surgery. After a median follow-up of 10 years, no structural events were detected. Sixteen out of three hundred and eighty-three (4.2%) patients developed biochemical events: 12/276 (4.3%) in group A and 4/107 (3.7%) in group B. The median time elapsed from surgery to detecting a biochemical event was 14.5 and 77.5 months in groups A and B, respectively. No patients performed additional treatments and were followed up with an active surveillance strategy. This study confirmed that patients with DTC at low risk of recurrence showed an excellent outcome in a medium long-term follow-up since no structural events were diagnosed. Significant variations in Tg/TgAb were detected in a few cases, all managed with an active surveillance strategy without the need for other treatments. Therefore, a relaxed follow-up with neck ultrasound and Tg/TgAb measurement is enough to early identify those very unusual cases of recurrence.

Vitamin D receptor polymorphisms associate with the efficacy and toxicity of radioiodine-131 therapy in patients with differentiated thyroid cancer.

Radioiodine-131 (I-131) therapy is the common postoperative adjuvant therapy for differentiated thyroid cancer (DTC) However, methods to evaluate the efficacy and toxicity of I-131 on DTC are still lacking. To evaluate the association between vitamin D receptor (VDR) gene polymorphisms and the efficacy and toxicity of I-131 in DTC patients. A total of 256 DTC patients who received I-131 therapy were enrolled. The patients were divided into effective group and ineffective group. 4 single nucleotide polymorphisms (SNPs) (rs7975232, rs731236, rs1544410 and rs10735810) of VDR were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) Cell counting kit-8 (CCK-8) and flow cytometry were used to detect the proliferation and apoptosis of thyroid cancer cells. Patients in effective group had more CC genotype of rs7975232 and GG genotype of rs10735810 compared with patients in ineffective group They were also independent factors for influencing the efficacy of I-131. PTC-1 and FTC-133 cells transfected with CC genotype of rs7975232 showed lower proliferative activity and higher apoptosis rate after being treated with I-131 In addition, patients with CC genotype at rs7975232 had fewer adverse reactions after I-131 treatment. VDR gene polymorphisms may be associated with the efficacy and toxicity of I-131 in DTC patients, which will help to personalize the treatment for patients.

Comparing the prognostic impact of 131I and/or artificial liver support system on liver function failure combined with hyperthyroidism.

Hyperthyroidism, a prevalent endocrine disorder, can lead to complications such as liver failure due to the liver's essential role in thyroid hormone metabolism. The study aimed to elucidate the respective contributions of 131I and/or ALSS in managing hyperthyroidism alongside liver failure. A retrospective analysis was carried out on 74 patients diagnosed with severe liver failure in the context of Graves' disease. Patients were categorized into three groups: group A (n = 34) received 131I treatment, group B (n = 17) underwent 131I and ALSS treatment, and group C (n = 24) received artificial liver support system (ALSS) treatment alone. Throughout the treatment period, the liver function indexes in all groups exhibited a declining trend. The thyroid function of group A and group B treated with 131I was significantly improved compared to that before treatment. There was no significant change in thyroid function in group C. After the correction of hyperthyroidism, significant improvements were observed in the liver function of individuals in groups A and B, particularly with more noticeable amelioration compared to group C. After two months of treatment, the efficacy rates for the three groups were 79.41%, 82.35%, and 60.87% respectively. Mortality rates of the three groups were 5.88%, 17.65%, and 36% (P < 0.01). Group B, receiving both 131I and ALSS treatments, exhibited a lower mortality rate than group C. In cases of severe liver failure accompanied by hyperthyroidism, prompt administration of 131I is recommended to alleviate the adverse effects of hyperthyroidism on liver function and facilitate a conducive environment for the recovery of liver functionality.

Early and long-term responses of intestinal microbiota and metabolites to 131I treatment in differentiated thyroid cancer patients

BackgroundMultiple high doses of 131I therapy in patients with differentiated thyroid cancer (DTC) might disrupt the balance of gut microbiota and metabolites. This study aimed to investigate the alterations of intestinal bacteria and metabolism over two courses of 131I therapy, explore the interactions, and construct diagnostic models reflecting enteric microecology based on 131I therapy.MethodsA total of 81 patients were recruited for the first 131I therapy (131I-1st), among whom 16 received a second course (131I-2nd) after half a year. Fecal samples were collected 1 day before (Pre-131I-1st/2nd) and 3 days after (Post-131I-1st/2nd) 131I therapy for microbiome (16S rRNA gene sequencing) and metabolomic (LC–MS/MS) analyses.ResultsA total of six microbial genera and 11 fecal metabolites enriched in three pathways were identified to show significant differences between Pre-131I-1st and other groups throughout the two courses of 131I treatment. In the Post-131I-1st group, the beneficial bacteria Bifidobacterium, Lachnoclostridium, uncultured_bacterium_f_Lachnospiraceae, and Lachnospiraceae_UCG004 were abundant and the radiation-sensitive pathways of linoleic acid (LA), arachidonic acid, and tryptophan metabolism were inhibited compared with the Pre-131I-1st group. Compared with the Pre-131I-1st group, the Pre-131I-2nd group exhibited a reduced diversity of flora and differentially expressed metabolites, with a low abundance of beneficial bacteria and dysregulated radiation-sensitive pathways. However, less significant differences in microbiota and metabolites were found between the Pre/Post-131I-2nd groups compared with those between the Pre/Post-131I-1st groups. A complex co-occurrence was observed between 6 genera and 11 metabolites, with Lachnoclostridium, Lachnospiraceae_UCG004, Escherichia-Shigella, and LA-related metabolites contributing the most. Furthermore, combined diagnostic models of charactered bacteria and metabolites answered well in the early, long-term, and dose-dependent responses for 131I therapy.ConclusionsDifferent stages of 131I therapy exert various effects on gut microecology, which play an essential role in regulating radiotoxicity and predicting the therapeutic response.

Automatic prediction of non-iodine-avid status in lung metastases for radioactive I131 treatment in differentiated thyroid cancer patients.

The growing incidence of differentiated thyroid cancer (DTC) have been linked to insulin resistance and metabolic syndrome. The imperative need for developing effective diagnostic imaging tools to predict the non-iodine-avid status of lung metastasis (LMs) in differentiated thyroid cancer (DTC) patients is underscored to prevent unnecessary radioactive iodine treatment (RAI). Primary cohort consisted 1962 pretreated LMs of 496 consecutive DTC patients with pretreated initially diagnosed LMs who underwent chest CT and subsequent post-treatment radioiodine SPECT. After automatic lesion segmentation by SE V-Net, SE Net deep learning was trained to predict non-iodine-avid status of LMs. External validation cohort contained 123 pretreated LMs of 24 consecutive patients from other two hospitals. Stepwise validation was further performed according to the nodule's largest diameter. The SE-Net deep learning network yielded area under the receiver operating characteristic curve (AUC) values of 0.879 (95% confidence interval: 0.852-0.906) and 0.713 (95% confidence interval: 0.613-0.813) for internal and external validation. With the LM diameter decreasing from ≥10mm to ≤4mm, the AUCs remained relatively stable, for smallest nodules (≤4mm), the model yielded an AUC of 0.783. Decision curve analysis showed that most patients benefited using deep learning to decide radioactive I131 treatment. This study presents a noninvasive, less radioactive and fully automatic approach that can facilitate suitable DTC patient selection for RAI therapy of LMs. Further prospective multicenter studies with larger study cohorts and related metabolic factors should address the possibility of comprehensive clinical transformation.

Prognostic analysis of 131I efficacy after papillary thyroid carcinoma surgery based on CT radiomics.

To develop and validate a radiomics-clinical combined model combining preoperative CT and clinical data from patients with papillary thyroid carcinoma (PTC) to predict the efficacy of initial postoperative 131I treatment. A total of 181 patients with PTC who received total thyroidectomy and initial 131I treatment were divided into training and testing sets (7:3 ratio). Univariate analysis and multivariate logistic regression were used to screen clinical factors affecting the therapeutic response to 131I treatment and construct a clinical model. Radiomics features extracted from preoperative CT images of PTCs were dimensionally reduced through recursive feature elimination and least absolute shrinkage and selection operator. Logistic regression was used to establish a radiomics model, and a radiomics-clinical combined model was developed by integrating the clinical model. The area under the curve (AUC), sensitivity, and specificity were used to evaluate the prediction performance of each model. Multivariate analysis revealed that pre-131I treatment sTg was an independent clinical risk factor affecting the efficacy of initial 131I treatment (P = 0.002), and the AUC, sensitivity, and specificity for predicting the efficacy of initial 131I treatment were 0.895, 0.899, and 0.816, respectively. After dimensionality reduction, 14 key CT radiomics features of PTCs were included. The established radiomics model predicted the efficacy of 131I treatment in the training and testing sets with AUCs of 0.825 and 0.809, sensitivities of 0.828 and 0.636, and specificities of 0.745 and 0.944, respectively. The combined model improved the AUC, sensitivity, and specificity in both sets. The preoperative CT-based radiomics model can effectively predict the efficacy of initial postoperative 131I treatment in patients with intermediate- or high-risk PTC, and the radiomics-clinical combined model exhibits better predictive performance.

The Effect of I-131 Treatment on Complete Blood Count

Radioactive iodine-131 (RAI) treatment may cause suppression in the bone marrow. In this study, hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts will be compared before total thyroidectomy and 6 months after RAI treatment. 97 patients (76 females, 21 males) with a diagnosis of well-differentiated thyroid cancer who had undergone total thyroidectomy and received 50-200 mCi RAI treatment were included in the study. Hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts of the patients in the last month before the treatment and in the sixth month after the treatment were compared retrospectively. When the whole patients were analyzed, hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts in pretreatment were statistically lower than after-treatment values. While hemoglobin levels of female patients were similar before and after treatment, lymphocyte, thrombocyte, and leukocyte counts were statistically lower before treatment. Hemoglobin levels, leukocyte,and thrombocyte counts were similar before and after treatment, while lymphocytes decreased significantly after RAI treatment. Thyroid cancer patients who received 50-200 mCi RAI treatment after total thyroidectomy, have bone marrow suppression but are still in normal mean value ranges. This mild bone marrow suppression is more prominent in female patients than in male patients.

Disrupted gut microecology after high-dose 131I therapy and radioprotective effects of arachidonic acid supplementation

BackgroundDespite the potential radiotoxicity in differentiated thyroid cancer (DTC) patients with high-dose 131I therapy, the alterations and regulatory mechanisms dependent on intestinal microecology remain poorly understood. We aimed to identify the characteristics of the gut microbiota and metabolites in DTC patients suffering from high-dose 131I therapy and explore the radioprotective mechanisms underlying arachidonic acid (ARA) treatment.MethodsA total of 102 patients with DTC were recruited, with fecal samples collected before and after 131I therapy for microbiome and untargeted and targeted metabolomic analyses. Mice were exposed to total body irradiation with ARA replenishment and antibiotic pretreatment and were subjected to metagenomic, metabolomic, and proteomic analyses.Results131I therapy significantly changed the structure of gut microbiota and metabolite composition in patients with DTC. Lachnospiraceae were the most dominant bacteria after 131I treatment, and metabolites with decreased levels and pathways related to ARA and linoleic acid were observed. In an irradiation mouse model, ARA supplementation not only improved quality of life and recovered hematopoietic and gastrointestinal systems but also ameliorated oxidative stress and inflammation and preserved enteric microecology composition. Additionally, antibiotic intervention eliminated the radioprotective effects of ARA. Proteomic analysis and ursolic acid pretreatment showed that ARA therapy greatly influenced intestinal lipid metabolism in mice subjected to irradiation by upregulating the expression of hydroxy-3-methylglutaryl-coenzyme A synthase 1.ConclusionThese findings highlight that ARA, as a key metabolite, substantially contributes to radioprotection. Our study provides novel insights into the pivotal role that the microbiota-metabolite axis plays in radionuclide protection and offers effective biological targets for treating radiation-induced adverse effects.

Dosimetry during iodine-131 therapy - a technical point of view from a single centre's own experience.

Nuclear medicine uses radionuclides in medicine for diagnosis, staging, therapy, and monitoring the response to therapy. The application of radiopharmaceutical therapy for the treatment of certain diseases is well-established, and the field is expanding. Internal dosimetry is multifaceted and includes different workflows, as well as various calculations based on patient- specific dosimetry. The objective of this study was to introduce the technical issues which might occur during iodine-131 (¹³¹I) dosimetry performed in nuclear medicine departments. Retrospective analysis was performed on a group of 44 patients with papillary thyroid cancer who between May 2021 and October 2021 underwent a 131I treatment: 80-100 mCi (2200-3700 MBq, based on the previous medical history and stage of the disease). Patients underwent a series of ¹³¹I therapy scans using gamma camera Discovery NM 670 CT. Whole body scan (WBS) was performed 2, 4, 24 and 48 hours after ¹³¹I administration. Additionally, after 24 hours of single photon emission computed tomography/ computed tomography, two fields of view (SPECT/CT 2-FOV) were performed from the mid-head to the bladder. During the dosimetry procedure, several issues arise. Firstly, after receiving therapeutic doses of ¹³¹I, patients should remain in their rooms until the appropriate activity is achieved before being transported to the diagnostic room. Secondly, the walls between examination rooms meet the requirements for accurate diagnosis but not for therapy, leading to the occurrence of artefacts in patients examined behind the wall, potentially influencing the examination results. Thirdly, personnel in the control room also experience additional exposure (10 times greater than in the case of standard diagnostic procedure). The dosimetry in patients in whom therapeutic procedures are performed with the use of isotopes is mandatory according to Polish and European law, technical issues which occur during the dosimetry procedures might influence the organization of the work in departments.

Recurrent Middle Eastern Differentiated Thyroid Carcinoma Has Worse Outcomes Than Persistent Disease.

Background: Despite the excellent prognosis of differentiated thyroid carcinoma (DTC), recurrent and persistent disease remain major challenges. Emerging studies to differentiate between recurrent and persistent disease are controversial, with studies from the Middle East lacking. Methods: We retrospectively analyzed 1691 patients who underwent surgery ± I131 treatment for DTC, with a median age of 38.7 years and median follow-up of 95.3 months. Results: We found a similar prevalence rate for persistent and recurrent disease (17.7% vs. 17.9%) in Middle Eastern DTC patients. Relative to patients with persistent disease, patients with recurrent disease were significantly older (median age: 36.1 vs. 45.8 years; p < 0.0001) and were more likely to have ATA high-risk tumors (61.5% vs. 75.2%; p = 0.0003). On multivariate logistic regression analysis, both T and N status were independent predictors for recurrent as well as structural persistent disease. However, older age, bilaterality and extrathyroidal extension were independent predictors of recurrent disease alone. In addition, patients with recurrent disease had significantly worse cancer-specific survival (p < 0.0001), which remained significant in multivariate analysis. Conclusions: Although persistent and recurrent disease in Middle Eastern DTC have similar frequencies, recurrent disease has worse outcomes compared to persistent disease. Hence, differentiating recurrence from persistence has great potential clinical relevance for therapeutic and follow-up approaches, contributing to improving the outcomes of DTC patients of Middle Eastern ethnicity.

Quantifying salivary iodine biomarker using total reflection X-ray fluorescence (TXRF): A method for assessing and monitoring iodine status simulated by Monte Carlo

Iodine stands as a vital trace element essential crucial for synthesizing thyroid hormones, which are essential for regulating metabolism and tissue growth. The “gold standard” for assessing iodine status in a population quantifies the iodine content in urine samples and is based on Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). Such method, or methods involving the readings of the Sandell-Kolthoff (SK) reaction, require complex sample preparations and the use of several toxic chemical elements. However, recent studies have shown a strong correlation between urinary iodine content (UIC) and iodine present in saliva. Using Monte Carlo simulations, this paper presents a TXRF-based method to quantify salivary iodine biomarker for assessing and monitoring iodine status. In the theoretical analysis, mono and polychromatic (filtered) excitation sources are considered. The detection and quantification limits of iodine, as well as the calibration curves for mass recovery, used the strong I Kα1 and I Kα2 lines. It was found that the optimal X-ray excitation source energy for iodine detection is 50 keV monochromatic X-rays. In contrast, using simulated spectra from a tungsten anode target, the best result was found at 70 kVp (peak voltage), after filtering the white beam with a copper absorber. Detection limits of iodine are 0.121 ng and 2.292 ng, for mono and polychromatic sources, respectively. The theoretical results of this paper show that TXRF could be a fast, simple and accurate alternative to ICP-MS or SK reaction-based methods. Of clinical significance, quantifying salivary iodine using TXRF to assess and monitor iodine status could be particularly helpful to patients undertaking 131I treatment. In addition, it could be used in epidemiological field studies to determine iodine deficiency/excess in children and pregnant women.

Effect of recombinant human thyroid stimulating hormone on radioactive iodine uptake by thyroid carcinoma in dogs.

The high doses of radioiodine-131 (131I) and, subsequently, the high radioactive burden for dog and environment warrants optimization of 131I therapy in dogs with thyroid carcinoma (TC). To evaluate the effect of a revised protocol with recombinant human thyroid stimulating hormone (rhTSH) on tumor radioactive iodine uptake (RAIU) in dogs with TC. Nine client-owned dogs diagnosed with TC. A prospective cross-over study in which tumor RAIU was calculated and compared at 8 hours (8h-RAIU) and 24 hours (24h-RAIU) after injection of radioactive iodine-123 (123I), once with and once without rhTSH (ie, 250 μg, IM, 24 and 12 hours before 123I) in each dog. Simultaneously, serum total thyroxine (TT4) and TSH were measured at baseline (T0), and 6 (T6), 12 (T12), 24 (T24), and 48 hours (T48) after the first rhTSH administration. Tumor RAIU was significantly higher at 24 hours with rhTSH compared to no rhTSH (mean difference = 8.85%, 95% CI of [1.56; 16.14]; P = .03), while this was non-significant at 8 hours (mean difference = 4.54%, 95% CI of [0.35; 8.73]; P = .05). A significant change of serum TT4 (median difference T24 - T0 = 35.86 nmol/L, interquartile range [IQR] = 15.74 nmol/L) and TSH (median difference T24 - T0 = 1.20 ng/mL, IQR = 1.55 ng/mL) concentrations occurred after administration of rhTSH (P < .001). Recombinant human TSH could optimize 131I treatment in dogs with TC by increasing tumor RAIU and thus 131I treatment efficacy.