The prophylactic antiemetic therapies in management of differentiated thyroid cancer patients with radioactive iodine therapy: a single-center, non-randomized clinical trial.

Objective: The present study was to investigate three different single-drug regimens to show which was more effective to reduce radioactive iodine therapy (RAI) associated nausea and vomiting, and to compare the occurrence of long-term gastrointestinal diseases after RAI therapy. Method: We performed a single-center, non-randomized clinical trial among patients who underwent RAI therapy from March 2016 to July 2022. Enrolled patients were divided into four cohorts based on the date of the treatment. cohort 1, with no preventive antiemetics; cohort 2, received 20 mg of pantoprazole per day for 3 days; cohort 3, received a 10 mg metoclopramide tablet two times daily for 3 days; cohort 4, oral ondansetron, 8 mg, twice daily for 3 days. The primary endpoints were proportion of patients who experience vomiting episodes and nausea during the 7-day hospital period. Secondary end points included Functional Living Index Emesis (FLIE) quality-of life questionnaires and the occurrence of gastrointestinal diseases. Results: A total of 1755 patients were analyzed, comprised of 1299 (74.0%) women and 456 (26.0%) men, with a median age of 44 years (range 18-78 years). The characteristics of patient were similar within the four groups. 465 (26.4%) patients developed RAI-associated nausea, and 186 (14.4%) patients developed RAI-associated vomiting. The rate of nausea was significantly decreased in the patients who were taking ondansetron when compared with the other cohorts (P<0.05), while the rate of vomiting (≥6 episodes) was slightly lower. As secondary endpoint, FLIE measures ondansetron scored highly compared to other cohorts, from baseline (mean score of 110.53 ± 17.54) to day 7 (mean score of 105.56 ± 12.48). In addition, 48 (2.7%) patients were found to be with gastrointestinal diseases at the end of one year follow up. Multiple RAI therapy and higher dose of I-131 per body weight revealed a significantly independent risk factors of developing gastrointestinal disorders. Conclusions: In conclusion, the present study demonstrated that short-term ondansetron could be an effective prophylactic agent in controlling RAI-associated nausea and vomiting. Furthermore, the risk of developing gastrointestinal disorders was significantly higher for patients with multiple RAI therapy and higher dose of I-131 per body weight.

Factors affecting timing of hypothyroidism following radioactive iodine therapy (RAIT) for patients with Graves' disease: A 12-month observational study.

BACKGROUND: This retrospective study analyzed factors influencing hypothyroidism development after radioactive iodine therapy for Graves' disease. PATIENTS AND METHODS: Three hundred and three patients with Graves' disease treated with radioactive iodine (RAI) from 2013 to 2022 at two Egyptian hospitals were included. Data collected included demographics, lab values, thyroid imaging, RAI doses, and outcomes. Patients were followed for ≥1 year to assess hypothyroidism onset. RESULTS: At the end of 1 year, around 79.5% of the individuals developed hypothyroidism while 12.5% continued to experience hyperthyroidism. The onset of hypothyroidism occurred earlier in those with thyroid volume (≤75.5 cm 3 ), lower thyroid weight (≤84.7 g), thyroid uptake (≤18.8%), and higher RAI dose/volume (≥0.1022 mCi/ml) ( P  < 0.001). Additionally, there was a correlation between anti-thyroid peroxidase (anti-TPO) antibodies and faster development of hypothyroidism compared to those who were negative for antibodies (2.9 vs 8.9 months, P  = 0.001). When considering factors in analysis it was found that anti-TPO antibodies were the only independent predictor, for developing hypothyroidism (hazard risk 30.47, P  < 0.001). Additionally, thyroid volume and uptake independently predicted successful treatment outcomes ( P  < 0.05). CONCLUSION: Positive anti-TPO antibodies strongly predict hypothyroidism risk after RAI therapy for Graves' disease. Smaller thyroid size, lower uptake, and higher RAI dose/volume correlate with earlier hypothyroidism onset but are less significant predictors than anti-TPO status. Findings can guide RAI therapy personalization to optimize outcomes.

Protective effects of Panax Ginseng against 131I-induced genotoxicity in patients with differentiated thyroid cancer.

BACKGROUND: Radioiodine (131I) therapy (RAIT) is associated with oxidative stress (OS)-induced DNA damage in patients with differentiated thyroid cancer (DTC). The goal of this study was to evaluate the possible ameliorating effects of Panax Ginseng (PG) on RAIT-induced genotoxicity in patients with DTC. MATERIALS AND METHODS: Forty DTC patients who had received 131I (100 to 175 mCi) were enrolled in this study. The patients were randomly classified (n = 10) into control, placebo, PG1 groups (receiving 500 mg/day of PG for 2 days before RAIT), and PG2 group (receiving 500 mg/day of PG for 2 days before to 1 day after RAIT). Blood samples were collected before and 2 days after RAIT. Lymphocyte micronuclei (MN) frequency was measured using the MN assay. Serum total antioxidant capacity (TAC) and ischemia-modified albumin (IMA) were measured using colorimetric assays. Serum albumin, blood urea nitrogen (BUN), creatinine, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured using commercial kits. RESULTS: The mean of baseline MN frequency was the same in the four groups. RAIT increased the MN frequencies to at least three times the baseline values in the control (39 ± 5) and placebo groups (38 ± 6) (P < 0.001). PG caused a significant decrease in the MN frequencies in the treated groups compared to the control and placebo groups (P < 0.001). RAIT and PG administration had no significant effects on the serum IMA, TAC, and markers of liver and kidney toxicity. CONCLUSION: PG could be considered a useful remedy for the protection against RAIT-induced chromosomal damage in DCT patients.

Does Radioactive Iodine Treatment Damage the Lacrimal System?

PURPOSE: In this prospective study, we aimed to make a quantitative assessment of the lacrimal glands before and after radioactive iodine (RAI) treatment in patients with hyperthyroidism and thyroid cancer. METHODS: The study included 80 eyes of 40 patients. There were 25 patients in group 1 (hyperthyroid group) and 15 patients in group 2 (thyroid cancer group). Group 1 has received low dose ( 131 I) and group 2 high dose ( 131 I). Before, and at the first and sixth month after RAI treatment, all patients underwent ophthalmological examinations, Schirmer tests, TBUT tests, tear osmolarity (TO), and ocular surface examinations. RESULTS: The age and sex characteristics of both groups were similar. Although no significant change was observed in tear film tests before and after treatment in group 1, a significant decrease in Schirmer and TBUT values and a significant increase in TO were observed in group 2 in the first month after treatment. These values returned to normal in the sixth month. Although no Schirmer test was observed lower than 10 mm in any patient before RAI treatment, the Schirmer test was measured 5 to 10 mm in 4 (10%) patients in group 2 in the first month after treatment. Again, in these patients, TBUT was below 10 seconds and TO was greater than 308 mOsm/L. CONCLUSIONS: In this study, although no change was observed in tear function tests in patients receiving low doses of RAI, a decrease in tear secretion and an increase in TO were detected in patients receiving high doses in the early period.

Cancer Risk in Graves Disease with Radioactive 131I Treatment: A Nationwide Cohort Study.

Radioactive 131I (RAI) therapy has potential effects for the treatment of Graves disease (GD). However, whether RAI therapy for GD increases cancer risk remains controversial in medicine and public health. We aimed to investigate whether the risk of cancer increases in patients with GD receiving RAI therapy compared with those who did not. Methods: We used the Korean National Health Insurance Service's National Health Information Database from 2004 to 2020 and defined GD as prescribing antithyroid drugs, RAI, or thyroidectomy as a treatment for GD (International Classification of Diseases, 10th revision, E05 group). We investigated the hazard ratios (HRs) of overall and site-specific cancers associated with RAI in patients with GD. Subsequent cancer was defined as a primary malignancy treated at least 1 y after RAI therapy. Results: In total, 10,737 patients with GD who received RAI therapy (7,193 women, 67.0%; mean age, 43.7 ± 13.4 y) were matched to 53,003 patients with GD who had never received RAI treatment (35,471 women, 66.9%; mean age, 43.8 ± 13.2 y) in a 1:4-5 ratio by age, sex, and health checkup data. The median follow-up duration was 8.7 y (interquartile range, 5.2-12.1 y), and the median cumulative RAI dose was 555 MBq (interquartile range, 370-630 MBq) in the RAI therapy group. During 2004-2020, the overall subsequent cancer rates were 5.66 and 5.84 per 1,000 person-years in the RAI and non-RAI groups, respectively, with an unadjusted HR of 0.97 (95% CI, 0.88-1.06); this remained at 0.96 (95% CI, 0.83-1.10) after adjustment for multiple clinical confounding factors. For cancer subtypes, the risk of leukemia was significantly increased, with an HR of 2.39 (95% CI, 1.17-4.91). However, a loss of statistical significance was observed after adjusting for confounding factors, which may be attributed to the limited number of absolute events. Moreover, cancer-specific mortality was not different between the RAI and the non-RAI groups, with an adjusted HR of 0.99 (95% CI, 0.66-1.47). Conclusion: This study identified that the overall cancer risk in patients with GD who received RAI therapy compared with those who did not was not significant in Korea. Further long-term studies are needed to determine the risks and advantages of RAI therapy in patients with GD.

Blood pressure in hyperthyroid cats before and after radioiodine treatment.

BACKGROUND: Hyperthyroid cats commonly have systemic hypertension, with a reported prevalence of 7% to 48%. Although hypertension might be expected to resolve once treatment restores euthyroidism, it can persist or only first develop after treatment. OBJECTIVES: To determine the proportion of hyperthyroid cats with hypertension (systolic blood pressure [SBP] ≥160 mm Hg), persistence or first development of hypertension after successful radioiodine treatment, and correlation of post-treatment hypertension with azotemia or hypothyroidism. ANIMALS: Four hundred one hyperthyroid nonazotemic cats were included in the study. METHODS: Prospective, cross-sectional and before-and-after studies. All hyperthyroid cats had SBP measured by Doppler; 255 had SBP rechecked 6 months after successful radioiodine (131I) treatment. RESULTS: Of untreated hyperthyroid cats, 108/401 (27%) were hypertensive. A higher proportion of hypertensive cats were nervous/excited compared with normotensive cats (47% vs 12%; P < .001). Of the initially hypertensive cats, 87/108 cats were reexamined after 131I treatment; 43/87 (49%) cats normalized SBP, whereas 44/87 (51%) remained hypertensive. Of the initially normotensive cats, 16/168 (9.5%) first developed hypertension after successful 131I treatment. 7/60 (12%) of the 131I-treated hypertensive cats were azotemic and 9/60 (15%) were hypothyroid. A higher proportion of cats remaining hypertensive had nervous/excited demeanor than did normotensive cats (50% vs 17%; P < .001). CONCLUSIONS/CLINICAL IMPORTANCE: Hypertension, when present, resolves in many hyperthyroid cats after successful treatment. Hyperthyroid cats uncommonly develop new hypertension after treatment. Persistent or newly detected hypertension was unrelated to azotemia or iatrogenic hypothyroidism. More frequently perceived nervousness/anxiety in radioiodine-treated hypertensive cats suggests that many of these cats might have "situational" hypertension, as hyperthyroid-induced hypertension should resolve after treatment.

Incidence of Strabismus Post-Plaque Brachytherapy in Patients With Uveal Melanoma.

PURPOSE: To determine the incidence and type of strabismus in patients with uveal melanoma treated with plaque brachytherapy. DESIGN: Multicenter, retrospective incidence estimation study. METHODS: A total of 438 eyes of 438 patients with uveal melanoma treated with plaque brachytherapy between October 2011 and May 2021. Intervention was Iodine 125, and Palladium 103 plaque brachytherapy. The variables reviewed included incidence of nonresolving strabismus post-plaque brachytherapy, type of strabismus developed, extraocular muscles operated, and modality of treatment received. RESULTS: A total of 438 patients underwent plaque brachytherapy treatment for uveal melanoma. Eleven patients developed strabismus post-plaque brachytherapy (2.5%, n = 11/438). Of these patients, 5 (1.1%, n = 5/438) developed strabismus immediately postoperation. Specifically, 2 patients (0.5%, n = 2/438) developed strabismus immediately postoperation due to slipped muscles, 2 patients (0.5%, n = 2/438) due to decompensated phorias, and 1 patient (0.5%, n = 1/438) due to a fibrotic muscle. Six patients (1.4%, n = 6/438) developed late-onset sensory strabismus. A total of 355 patients (81.1%, n = 355/438) had their extraocular muscles disinserted during surgery, with the lateral rectus being the most common, accounting for 45.4% (n = 161/355), followed by the superior rectus at 26.8% (n = 95/355). Strabismus surgery was the most common treatment modality, comprising 72.7% (n = 8/11) of patients. CONCLUSIONS: The incidence of strabismus after plaque brachytherapy treatment for uveal melanoma was low and primarily classified as late-onset sensory strabismus. Previous studies may underestimate the long-term incidence of strabismus after plaque brachytherapy by focusing primarily on strabismus present immediately postoperatively.

Prophylactic effect of pilocarpine on acute sialadenitis following radioactive iodine therapy in thyroid cancer patients.

Purpose: Our aim was to evaluate the effect of prophylactic pilocarpine on acute salivary symptoms after radioactive iodine (RAI) therapy in patients with differentiated thyroid cancer. Methods: We enrolled 88 patients (76 women and 12 men; mean age: 47 years; range: 20-74 years) with differentiated thyroid cancer who received RAI. Patients were divided into pilocarpine (51 patients) and control (37 patients) groups. Pilocarpine was given orally, at a dose of 5 mg three times a day, from 2 days before and 12 days after RAI therapy. Symptoms and signs of acute sialadenitis within 3 months of RAI therapy were recorded. Results: During the 3 months after RAI therapy, 13 of the 88 patients (14.7%) developed acute symptomatic sialadenitis (swelling or pain of salivary glands). Acute salivary symptoms were reported by 4 (7.8%) and 9 (24.3%) patients in the pilocarpine and control groups, respectively. Acute salivary symptoms were less frequent in the pilocarpine than control group (p = 0.04), but did not differ by age, sex, or RAI dose (p = 0.3357, p = 0.428, and p = 0.2792). Conclusions: Pilocarpine reduced the likelihood of acute sialadenitis after RAI therapy in patients with differentiated thyroid cancer.

Clinical impact of proteinuria on renal function and treatment outcomes in patients with radioiodine-refractory thyroid cancer treated with lenvatinib.

Proteinuria has been described as a major on-target adverse event of lenvatinib, although its long-term impact on renal function and clinical outcomes remains unclear. We conducted a retrospective observational study to assess renal function and prognosis in patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC) receiving lenvatinib. Overall, 70 patients with RR-DTC treated with lenvatinib were enrolled. When proteinuria was observed, the dose and schedule of lenvatinib were adjusted to achieve a urine protein-to-creatinine ratio (UPCR) of less than 3.5 g/gCre according to the study protocols of recent pivotal trials. In total, 50 (71%) and 25 (36%) patients presented with any-grade and grade 3 proteinuria, respectively. Multivariate analysis revealed that age [>65; odds ratio (OR) 8.24, 95% confidence interval (CI) 1.74-39.00, p < 0.01], history of diabetes mellitus (OR 7.79, 95% CI 1.31-46.20, p = 0.02), and hypertension (OR 4.07, 95% CI 1.22-13.60, p = 0.02) were significantly associated with the development of grade 3 proteinuria. Overall, the median estimating glomerular filtration rate (eGFR) gradually decreased every 3 months during treatment. However, no significant deterioration in eGFR was observed in patients with grade 3 proteinuria compared with patients with grades 0-2 proteinuria until 48 months. Patients who developed proteinuria had better survival outcomes than those without proteinuria. In conclusion, the proteinuria grade was not significantly associated with decreased eGFR under UPCR monitoring in our study. Therefore, lenvatinib can carefully be continued targeting UPCR of less than 3.5 g/gCre.

Effect of previous administration of potassium iodine and different durations of low iodine diets for radioiodine therapy on the treatment of Graves' disease in iodine-rich areas.

PURPOSE: To examine whether adherence to a low-iodine diet (LID) enhances the therapeutic efficacy of radioiodine therapy (RAI) in Graves' hyperthyroidism (GH) in iodine-rich areas. METHODS: We retrospectively evaluated 185 patients with GH from Aichi (n = 114) and Hokkaido (n = 71) Prefectures. Patients aged ≥ 18 years with GH who underwent RAI between December 2012 and March 2022 were divided into subgroups based on pretreatment with anti-thyroid drug (ATD) or potassium iodide (KI). Patients were followed up with LID from 18 days (group A) or 7 days (group H) before RAI to 3 days after RAI. The dose of radioactive iodine 131 (131I) was adjusted to deliver > 100 Gy to the thyroid. The associations between urinary iodine concentration on UIC2 vs. 24hRU and UIC2 vs. the 1-year RAI success rate (SR) were investigated. RESULTS: Compared with UIC1, UIC2 was significantly decreased in all subgroups (P < 0.01). An inverse correlation between UIC2 and 24hRU was observed in the four groups; however, the difference was insignificant. The SR in groups A and H was 85% and 89%, respectively. Univariate analysis revealed no association between UIC2 and SR in each group. Additionally, stratification of the 185 patients into quartiles using UIC2 yielded no significant differences in SR (p = 0.79). CONCLUSIONS: LID sufficiently reduced UIC in patients undergoing RAI. Although a lower UIC2 may increase 24hRU, it did not increase the success of RAI. The benefit of LID in enhancing the efficacy of RAI in GH treatment remains uncertain.

A Pilot Nonrandomized Controlled Trial Examining the Use of Artificial Tears on the Radioactivity of Tears After Radioactive Iodine Treatment for Thyroid Cancer.

Background: Nasolacrimal duct obstruction (NLDO) is an adverse effect of high dose radioactive iodine (RAI) therapy for thyroid carcinoma. There are currently no established preventive measures. This study assesses whether preservative free artificial tears (PFATs) can decrease the 131I sodium iodide (131I) activity in the tears of patients following RAI therapy for thyroid carcinoma, and potentially serve as a preventive measure for RAI-associated NLDO. Methods: This non-randomized prospective pilot clinical trial recruited contact-lens wearing patients undergoing RAI therapy for thyroid cancer to self-administer PFATs into the right eye for four days starting on the day of RAI ingestion. Left eyes were the controls. While wearing contacts, patients self-administered PFATs per the following-Day 1: every 15 minutes for 2 hours, then every 30 minutes until bedtime, day 2: every hour for at least 12 hours, day 3: four times a day, and day 4: two times a day. Contact lenses were changed daily, and all lenses were collected one week later. Levels of 131I activity were measured by a well counter, decay-corrected, and converted to units of becquerel. Statistical analyses were performed to compare the 131I activities of the experimental and control eyes. Results: Sixteen eyes of eight patients treated with an average of 145.7 mCi (range 108-159) of 131I for papillary thyroid cancer were included. On day 1, artificial tears decreased the geometric mean 131I activity by 26% in the experimental eyes (p = 0.008). Artificial tears also decreased the geometric mean area under the curve over four days by 23% (p = 0.002). Conclusions: 131I is present in the tears following RAI therapy for thyroid carcinoma. Frequent PFATs starting on the day of RAI ingestion may decrease the level of 131I in the tears. This finding could have implications for lowering the risk of NLDO. Future multi-center clinical trials are needed to determine whether the use of artificial tears after RAI therapy may decrease the risk of NLDO. Clinical Trial Registration: NCT04327999.

The Presence of Anti-TPO Antibodies Increase the Likelihood of Post-I131 Hypothyroidism.

The use of radioactive iodine in the treatment of hyperthyroidism is common practice. However, a standardized treatment protocol with regard to radioactive iodine treatment (RAI) remains subject to discussion. We retrospectively analyzed 100 patient records. Patient diagnosis, age, gender, body mass index (BMI), dose of radioactive iodine, thyroid size, the 24 h radioiodine uptake (24 h RAIU) and protein bound iodine (PBI) were deducted, as well as the use of antithyroid drugs prior to RAI. Biochemical parameters were obtained, such as TSH, fT4, fT3, Anti-TPO, Anti-TG antibodies and thyroid stimulating antibodies. After 5 years of follow-up, 46% of the patients proved to be hypothyroid, whereas 8% of the patients were not cured after one dose of RAI. One year after RAI, a larger proportion of patients with a toxic nodule developed hypothyroidism compared to patients with a multinodular goiter (MNG) (44.2% vs. 21.2%). Radioactive iodine dose, PBI, RAIU, BMI, size of the thyroid gland, diagnosis, age and TPO-antibodies showed statistically significant differences in the development of hypothyroidism. Furthermore, thiamazole pretherapy was shown to be a predictor of hypothyroidism, as well as a high PBI value, exhibiting a positive predictive value of 85.2% when the PBI exceeded 0.16. We suggest a standardized measurement of TPO-Ab's to further determine their role in the development of hypothyroidism after RAI. The empirical dosing regimen was very effective, illustrating a 92% cure rate after 1 dose.

The potential role of reprogrammed glucose metabolism: an emerging actionable codependent target in thyroid cancer.

Although the incidence of thyroid cancer is increasing year by year, most patients, especially those with differentiated thyroid cancer, can usually be cured with surgery, radioactive iodine, and thyroid-stimulating hormone suppression. However, treatment options for patients with poorly differentiated thyroid cancers or radioiodine-refractory thyroid cancer have historically been limited. Altered energy metabolism is one of the hallmarks of cancer and a well-documented feature in thyroid cancer. In a hypoxic environment with extreme nutrient deficiencies resulting from uncontrolled growth, thyroid cancer cells utilize "metabolic reprogramming" to satisfy their energy demand and support malignant behaviors such as metastasis. This review summarizes past and recent advances in our understanding of the reprogramming of glucose metabolism in thyroid cancer cells, which we expect will yield new therapeutic approaches for patients with special pathological types of thyroid cancer by targeting reprogrammed glucose metabolism.

A Phase 1, Open-label, Dose-Ascending Study to Evaluate the Safety and Tolerability of the Therapeutic Radiopharmaceutical 131I-MIP-1095 for the Treatment of Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: 131I-MIP-1095 is a targeted radiotherapeutic that contains 131I, a ß-particle emitter, and MIP-1095, a urea-based ligand for prostate-specific membrane antigen. We report the first phase 1, dose-escalation study of 131I-MIP-1095 in patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: This study enrolled men with mCRPC refractory to second-generation antiandrogen(s) and taxane chemotherapy. Dosimetry/biodistribution assessments were performed. Safety and tolerability were determined in subjects who qualified for therapeutic administration of 131I-MIP-1095 with maximum tolerated activity examined in a dose-ascending manner (3 + 3 design methodology). Disease outcomes including prostate-specific antigen (PSA) change, tumor response, survival, and circulating tumor cell concentration were assessed. RESULTS: A total of 9 subjects with mCRPC were included in this study. On the basis of dosimetry results, 5 of 9 patients were treated: 3 in cohort 1 (50 mCi) and 2 in cohort 2 (75 mCi). Accrual stopped at the cohort 2 activity level in response to the US Food and Drug Administration mandate for 131I-MIP-1095 manufacturing concerns. Parotid/salivary glands (3.5 Gy/Bq), liver (2.2 Gy/Bq), kidneys (1.3 Gy/Bq), and spleen (0.7 Gy/Bq) demonstrated the greatest extent of 131I-MIP-1095 exposure. There were no deaths, serious adverse events, or drug discontinuations due to treatment-emergent adverse events. Grade 1-2 thrombocytopenia, anemia, leukopenia, and dry mouth most commonly occurred. One subject (33.3%) exhibited maximum decline for the PSA response of 50% or greater. CONCLUSION: 131I-MIP-1095 demonstrated favorable dosimetry, biodistribution, and safety, as well as a modest PSA response supporting further investigation for treatment of men with mCRPC.Clinical Trial Registration: ClinicalTrials.gov identifier: NCT03030885, Registered January 25, 2017 (https://clinicaltrials.gov/ct2/show/NCT03030885).

Assessment of three different radioiodine doses for ablation therapy of thyroid remnants: Efficiency, complications and patient comfort.

I-131 radioiodine (RAI) ablation removes postoperative residual tissue and facilitates follow-up in low- and intermediate-risk differentiated thyroid cancer (DTC). Although low doses have been reported to be as effective as higher doses for ablation, the doses administered still vary depending on the patient and the practitioner. We aimed to evaluate the ablation efficiency, complications, and length of stay (LOS) of patients with DTC treated with 3 different doses for ablation. Patients with DTC who received RAI therapy were retrospectively reviewed. One hundred thirty patients with low-intermediate-risk, according to American Thyroid Association classification, without known lymph nodes or distant metastases were included. Patients were divided into 3 groups as 30 to 50 mCi, 75 mCi, and 100 mCi. Residue thyroid and salivary glands were evaluated from 9 to 12 months post-RAI I-131 scans. No significant difference was found between groups regarding ablation success (P = .795). In multivariable analyses, pretreatment thyroglobulin (hazard ratio = 0.8, 95% confidence interval 0.601-0.952, P = .017) and anti- thyroglobulin antibody (hazard ratio = 1.0, 95% confidence interval 0.967-0.998, P = .024) were 2 independent predictors of ablation success. The mean LOS was 2.1 ±â€…0.3, 2.6 ±â€…0.6, and 2.9 ±â€…0.4 days, respectively, (P = .001). LOS rates of ≥ 3 days were 13.2%, 54.3%, and 84.8%, respectively. Mild decreases in hemoglobin, white blood cell (WBC), and platelet counts were observed in all groups after 6 weeks without any clinically significant findings. A lower rate of change in WBC counts was observed in the 30 to 50 mCi group compared to others. There was no dose-dependent difference regarding the early complaints questioned. Ablation with 30 to 50 mCi provides benefits such as shorter LOS, better patient comfort, less salivary gland dysfunction, and less WBC suppression, thus reducing costs without decreasing efficacy.

Genetic markers associated with adverse reactions of radioiodine therapy in thyroid cancer patients.

OBJECTIVES: Radioactive iodine therapy is considered for patients with certain clinicopathological factors that predict a significant risk of recurrence, distant metastases of thyroid cancer or disease-specific mortality. The aim of the study was to investigate the association between polymorphisms of genes, products of which are involved in the processes of DNA damage response and autophagy, and the adverse reactions of radioiodine therapy in thyroid cancer patients. METHODS: The study included 181 patients (37 men, 144 women; median age 56 [41; 66.3] years) with histologically confirmed thyroid cancer and a history of thyroidectomy who received radioiodine therapy. NFKB1, ATM, ATG16L2, ATG10, TGFB1, and TNF polymorphisms were determined by allele-specific realtime-PCR. RESULTS: The frequency of adverse reactions was the following: gastrointestinal symptoms - 57.9 %, local symptoms - 65.8 %, cerebral symptoms - 46.8 %, fatigue - 54.4 %; signs of sialoadenitis six months after radioiodine therapy - 25.2 %. TT genotype carriers of ATG10 rs1864183 had higher frequency of gastrointestinal symptoms (vs. CC+CT), the CC genotype carriers of ATG10 rs10514231 had significantly more frequent cerebral symptoms (vs. CT+TT), as well as AA genotype carriers of TGFB1 rs1800469 (vs. AG+GG). CC genotype of ATG10 rs10514231 increased the incidence of radioiodine-induced fatigue, whereas GA genotype of the ATM rs11212570 had a protective role against fatigue. TGFB1 rs1800469 was associated with signs of sialoadenitis six months after radioiodine therapy. CONCLUSIONS: Genetic factors may contribute to the occurrence of adverse reactions of radioiodine therapy in thyroid cancer patients.

The effect of radioiodine therapy on blood cell count in patients with differentiated thyroid cancer.

PURPOSE: This study aimed to investigate the long-term effects of radioiodine treatment (RAI) on blood cell counts in patients with differentiated thyroid cancer (DTC) and to describe the characteristics of patients at high risk for blood cell count abnormalities. METHODS: The study included patients with DTC who underwent RAI treatment between 2007 and 2017. Patients with regular complete blood counts for at least 5 years were included, while those with diseases or treatments that could influence blood count parameters were excluded. Blood cell count abnormalities were defined according to the Common Terminology Criteria for Adverse Events version 5.0, and factors influencing these abnormalities were examined. RESULTS: A total of 225 patients were analyzed. The mean age at diagnosis was 45.8 ± 13.9 years, and 76.5% of patients were female. In the first year after RAI, leukocyte, neutrophil, and lymphocyte counts were significantly reduced compared with baseline values. The leukocyte and neutrophil counts returned to baseline values by the third year, while the decrease in lymphocytes continued until the fifth year. Blood cell count abnormalities developed in 16 patients (7.1%) within the first year after RAI. Risk factors for blood cell count abnormalities within the first year after RAI included male sex, older age, T4, N1, and M1 disease, as well as higher RAI doses. In logistic regression analysis, only RAI dose remained independently associated with blood cell count abnormalities. CONCLUSION: These results suggest an association between RAI dose and blood cell count abnormalities, characterized by mild lymphopenia, and indicate that the risk of mild lymphopenia persists over time. Careful consideration should be given when planning high-dose RAI for patients at a high risk of blood cell count abnormalities, such as males with metastatic disease and of advanced age.

The efficacy and safety in radioactive iodine refractory thyroid cancer patients treated with sorafenib.

Background: Sorafenib included in Chinese medical insurance is the earliest targeted drug for radioactive iodine refractory differentiated thyroid cancer (RR-DTC). This study is to further demonstrate the clinical efficacy and safety of sorafenib used in Zhujiang Hospital of Southern Medical University. Methods: RR-DTC patients treated at our Department of Nuclear Medicine in Zhujiang Hospital of Southern Medical University (October 2017-May 2020) were retrospectively analyzed. Treatment effects, progression-free survival (PFS), and adverse effects (AEs) during medication were evaluated. Results: Of the 31 patients included, 26 patients were evaluated for efficacy with a median follow-up time of 17.5 months (4.0-51.0 months). The disease control rate (DCR) was 57.7% (n = 15) and the objective response rate (ORR) was 26.9% (n = 7). Most patients with disease control had thyroglobulin decreases of more than 60% (p = 0.004), ORRs were favorable in patients with lung metastasis and lung-only metastasis (p = 0.010 and 0.001, respectively). The PFS of the 26 patients analyzed was 16.5 months (95%CI: 14.41 -23.90 months). In the subgroup analysis, female, patients with lung-only metastasis, hand-foot skin syndrome (HFS), and thyroglobulin response ≥ 60% observed longer PFS (p = 0.038, 0.045, 0.035, and 0.000, respectively), while patients with bone metastasis had lower PFS (p = 0.035). The most common toxicity profile was HFS (93.5%), followed by diarrhea (83.9%), alopecia (74.2%). All the side effects were mainly grade 1-2. Grade 3-4 adverse reactions were more common in diarrhea and HFS. Conclusions: Sorafenib has promising efficacy in RR-DTC, especially in patients with lung metastasis and lung-only metastasis. The AEs of sorafenib were generally mild, and the main AE was HFS.

Retrospective Evaluation of Cytogenetic Effects Induced by Internal Radioiodine Exposure: A 27-Year Follow-Up Study.

Radioiodine (131I) is widely used in the treatment of hyperthyroidism and as an effective ablative therapy for differentiated thyroid cancer. Radioiodine (131I) constitutes 90% of the currently used therapies in the field of nuclear medicine. Here, we report the cytogenetic findings of a long-term follow-up study of 27 years on a male patient who received two rounds of radioiodine treatment within a span of 26 months between 1992 and 1994 for his papillary thyroid cancer. A comprehensive cytogenetic follow-up study utilizing cytokinesis blocked micronucleus assay, dicentric chromosome assay, genome wide translocations and inversions was initiated on this patient since the first administration of radioiodine in 1992. Frequencies of micronuclei (0.006/cell) and dicentric chromosomes (0.008/cell) detected in the current study were grossly similar to that reported earlier in 2019. The mFISH analysis detected chromosome aberrations in 8.6% of the cells in the form of both unbalanced and balanced translocations. Additionally, a clonal translocation involving chromosomes 14p; 15q was observed in 2 of the 500 cells analyzed. Out of the 500 cells examined, one cell showed a complex translocation (involving chromosomes 9, 10, and 16) besides 5 other chromosome rearrangements. Collectively, our study indicates that the past radioiodine exposure results in long-lasting chromosome damage and that the persistence of translocations can be useful for both retrospective biodosimetry and for monitoring chromosome instability in the lymphocytes of radioiodine exposed individuals.