{"title":"Efficacy assessment of repeat iodine-131 treatment in patients with papillary thyroid carcinoma assessed as biochemical incomplete response.","authors":"Zilin Wang, Chenghui Lu, Yihan Tian, Shiqi Wen, Meijing Huang, Congcong Wang, Xufu Wang, Fuxin Li, Wei Li, Yanhui Ji","doi":"10.1007/s12020-025-04232-9","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>Although most patients with Papillary Thyroid Carcinoma (PTC) have a favorable prognosis, some continue to have elevated serum Thyroglobulin (Tg) levels after surgery and ¹³¹I treatment, classified as a Biochemical Incomplete Response (BIR). According to the 2015 American Thyroid Association (ATA) guidelines, 20% of these patients will develop a Structural Incomplete Response (SIR). Doctors often recommend ¹³¹I retreatment without imaging evidence, hoping for benefits. However, the effectiveness of this treatment strategy is still not supported by evidence. The aim of this study is to explore the potential benefits by comparing Tg levels and their changes in patients who were retreated with <sup>131</sup>I and combining them with the results of follow-up assessment using Dynamic Risk Stratification (DRS).</p><p><strong>Methods: </strong>This retrospective study collected clinical data from patients with PTC who underwent ¹³¹I therapy after surgery at two medical centers. All of them were evaluated for Biochemical Incomplete Response (BIR) after initial treatment. Based on whether they received ¹³¹I retreatment, they were divided into two groups: the retreatment group and the no-retreatment group. Our primary outcome measures included basic clinical data, suppressed Tg, change in Tg levels, and DRS stratification at the last follow-up. The potential benefits of ¹³¹I retreatment were analyzed by comparing the changes in Tg levels and the DRS distribution at the end of follow-up between the two groups.</p><p><strong>Results: </strong>Patients with PTC assessed for BIR after initial therapy showed a greater reduction in Tg at short-term follow-up after ¹³¹I retreatment compared to the no retreatment group (0.84 ng/mL vs. 0.72 ng/mL). The one-sample Wilcoxon signed-rank test results were T = 6.001, p < 0.001 and T = 1.378, p = 0.168, respectively. At the end of follow-up, this treatment did not alter the DRS strata composition ratio (R = 3.06, p = 0.39). The area under the receiver operating characteristic curve for pre-ablation stimulated thyroglobulin (Ps-Tg) predicting non-remission status was 0.64 (95% CI: 0.55-0.73), with the highest Youden index (0.26) at a Ps-Tg cutoff of 20.5 ng/mL, corresponding to a sensitivity of 62.6% and a specificity of 63.3%. For the first suppressed Tg (sup-Tg) predicting non-remission, the AUC was 0.75 (95% CI: 0.67-0.84). The highest Youden index (0.40) was achieved at a sup-Tg cutoff of 1.85 ng/mL, corresponding to a sensitivity of 68.9% and a specificity of 70.8%.</p><p><strong>Conclusion: </strong>For patients with PTC who received <sup>131</sup>I therapy after surgery and are classified as BIR, <sup>131</sup>I retreatment may accelerate the decline in Tg levels over time but does not change the DRS distribution. Only few of patients have structural and/or functional lesions detected on the whole-body scan after <sup>131</sup>I retreatment. The Ps-Tg and first sup-Tg values after the first ¹³¹I treatment can help predict a non-remission state, with cutoff values of 20.5 ng/mL and 1.85 ng/mL, respectively.</p>","PeriodicalId":49211,"journal":{"name":"Endocrine","volume":" ","pages":""},"PeriodicalIF":3.0000,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Endocrine","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s12020-025-04232-9","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENDOCRINOLOGY & METABOLISM","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose: Although most patients with Papillary Thyroid Carcinoma (PTC) have a favorable prognosis, some continue to have elevated serum Thyroglobulin (Tg) levels after surgery and ¹³¹I treatment, classified as a Biochemical Incomplete Response (BIR). According to the 2015 American Thyroid Association (ATA) guidelines, 20% of these patients will develop a Structural Incomplete Response (SIR). Doctors often recommend ¹³¹I retreatment without imaging evidence, hoping for benefits. However, the effectiveness of this treatment strategy is still not supported by evidence. The aim of this study is to explore the potential benefits by comparing Tg levels and their changes in patients who were retreated with 131I and combining them with the results of follow-up assessment using Dynamic Risk Stratification (DRS).
Methods: This retrospective study collected clinical data from patients with PTC who underwent ¹³¹I therapy after surgery at two medical centers. All of them were evaluated for Biochemical Incomplete Response (BIR) after initial treatment. Based on whether they received ¹³¹I retreatment, they were divided into two groups: the retreatment group and the no-retreatment group. Our primary outcome measures included basic clinical data, suppressed Tg, change in Tg levels, and DRS stratification at the last follow-up. The potential benefits of ¹³¹I retreatment were analyzed by comparing the changes in Tg levels and the DRS distribution at the end of follow-up between the two groups.
Results: Patients with PTC assessed for BIR after initial therapy showed a greater reduction in Tg at short-term follow-up after ¹³¹I retreatment compared to the no retreatment group (0.84 ng/mL vs. 0.72 ng/mL). The one-sample Wilcoxon signed-rank test results were T = 6.001, p < 0.001 and T = 1.378, p = 0.168, respectively. At the end of follow-up, this treatment did not alter the DRS strata composition ratio (R = 3.06, p = 0.39). The area under the receiver operating characteristic curve for pre-ablation stimulated thyroglobulin (Ps-Tg) predicting non-remission status was 0.64 (95% CI: 0.55-0.73), with the highest Youden index (0.26) at a Ps-Tg cutoff of 20.5 ng/mL, corresponding to a sensitivity of 62.6% and a specificity of 63.3%. For the first suppressed Tg (sup-Tg) predicting non-remission, the AUC was 0.75 (95% CI: 0.67-0.84). The highest Youden index (0.40) was achieved at a sup-Tg cutoff of 1.85 ng/mL, corresponding to a sensitivity of 68.9% and a specificity of 70.8%.
Conclusion: For patients with PTC who received 131I therapy after surgery and are classified as BIR, 131I retreatment may accelerate the decline in Tg levels over time but does not change the DRS distribution. Only few of patients have structural and/or functional lesions detected on the whole-body scan after 131I retreatment. The Ps-Tg and first sup-Tg values after the first ¹³¹I treatment can help predict a non-remission state, with cutoff values of 20.5 ng/mL and 1.85 ng/mL, respectively.
期刊介绍:
Well-established as a major journal in today’s rapidly advancing experimental and clinical research areas, Endocrine publishes original articles devoted to basic (including molecular, cellular and physiological studies), translational and clinical research in all the different fields of endocrinology and metabolism. Articles will be accepted based on peer-reviews, priority, and editorial decision. Invited reviews, mini-reviews and viewpoints on relevant pathophysiological and clinical topics, as well as Editorials on articles appearing in the Journal, are published. Unsolicited Editorials will be evaluated by the editorial team. Outcomes of scientific meetings, as well as guidelines and position statements, may be submitted. The Journal also considers special feature articles in the field of endocrine genetics and epigenetics, as well as articles devoted to novel methods and techniques in endocrinology.
Endocrine covers controversial, clinical endocrine issues. Meta-analyses on endocrine and metabolic topics are also accepted. Descriptions of single clinical cases and/or small patients studies are not published unless of exceptional interest. However, reports of novel imaging studies and endocrine side effects in single patients may be considered. Research letters and letters to the editor related or unrelated to recently published articles can be submitted.
Endocrine covers leading topics in endocrinology such as neuroendocrinology, pituitary and hypothalamic peptides, thyroid physiological and clinical aspects, bone and mineral metabolism and osteoporosis, obesity, lipid and energy metabolism and food intake control, insulin, Type 1 and Type 2 diabetes, hormones of male and female reproduction, adrenal diseases pediatric and geriatric endocrinology, endocrine hypertension and endocrine oncology.