Multiple-factor analysis of the first radioactive iodine therapy in post-operative patients with differentiated thyroid cancer for achieving a disease-free status

Effects of a mobile health intervention based on a multitheoretical model of health behavior change on anxiety and depression, fear of cancer progression, and quality of life in patients with differentiated thyroid cancer: A randomized controlled trial

BACKGROUND

Despite the high cure rate of differentiated thyroid cancer (DTC), patients endure side effects from treatment and psychological distress, impacting their quality of life. The potential of mobile health (mHealth) interventions to address these issues remains unexplored. The purpose of this study is to develop an mHealth intervention based on the Multi-Theoretical Model of Health Behavior Change (MTM) and evaluate its impact on reducing anxiety, depression, fear of cancer progression, and enhancing quality of life in DTC patients.

METHODS

A single-blind, single-center, prospective, randomized controlled trial was conducted. One hundred and eleven consecutive DTC patients from Harbin Medical University's Fourth Hospital were enrolled from March 2023 to March 2024. Participants were randomized into a control group and an intervention group that received a 3-month mHealth intervention based on MTM theory. Outcomes were assessed using web-based questionnaires at baseline and conclusion.

RESULTS

One hundred four patients with DTC completed the study, with 7 lost to follow-up (6.3%). The intervention group experienced a significant drop in PHQ-4 scores post-MTM-mHealth intervention (P < .026), with no change in the control group, demonstrating a significant difference. The intervention group also had significantly lower anxiety (P < .015) and depression (P < .032) scores compared to controls. All PHQ-4 scores improved in the intervention group except for "Little interest or pleasure in doing things." Anxiety levels were significantly lower in the intervention group (P < .026) but remained unchanged in controls. The control group exhibited a significant increase in FCR-4 scores at follow-up, differing from the intervention group (P < 0.001). Quality of life scores did not differ at baseline but saw a significant improvement in the intervention group, while the control group experienced no significant change. The intervention group had higher VAS scores (P < .030) and greater health education satisfaction across all dimensions (P < .019).

CONCLUSIONS

The MTM-based mHealth intervention significantly benefits DTC patients by reducing anxiety, fear of cancer recurrence, and improving quality of life, though its effect on depression requires further investigation.

TRIAL REGISTRATION

China Clinical Trial Registry ChiCTR2200064321.

Impact of a mobile health intervention based on multi-theory model of health behavior change on self-management in patients with differentiated thyroid cancer: protocol for a randomized controlled trial

Introduction

Theoretical models of health behavior are important guides for disease prevention and detection, treatment and rehabilitation, and promotion and maintenance of physical and mental health, but there are no intervention studies related to differentiated thyroid cancer (DTC) that use theoretical models of health as a guide. In this study, we used a microblogging platform as an intervention vehicle and mobile patient-doctor interactive health education as a means of intervention, with the aim of improving the health behaviors of DTC patients as well as the corresponding clinical outcomes.

Methods

This research project is a quantitative methodological study, and the trial will be a single-blind, single-center randomized controlled trial conducted at the Fourth Hospital of Harbin Medical University in Harbin, Heilongjiang Province. The study subjects are patients over 18 years of age with differentiated thyroid cancer who were given radioactive iodine-131 therapy as well as endocrine therapy after radical surgery for thyroid cancer. The intervention group will receive MTM-mhealth, and the realization of health education will rely on the smart terminal WeChat platform. Routine discharge education will be given to the control group at discharge. The primary outcome will be change in thyroid-stimulating hormone (TSH) from baseline and at 3 and 6 months of follow-up, and secondary outcomes will include change in self-management behavior, social cognitive and psychological, and metabolic control.

Discussion

This study will explore a feasible mHealth intervention program applied to a population of DTC patients using the Multi-theory model of health behavior change (MTM) as a guide, with the aim of evaluating the MTM-based intervention program for clinical outcome improvement in DTC patients, as well as determining the effectiveness of the MTM-based intervention program in improving self-management skills in DTC patients. The results of this study will indicate the feasibility as well as the effectiveness of the application of health theoretical modeling combined with mHealth applications in disease prognostic health management models, and provide policy recommendations and technological translations for the development of mobility-based health management applications in the field of health management.

Porous organic materials for iodine adsorption

The nuclear industry will continue to develop rapidly and produce energy in the foreseeable future; however, it presents unique challenges regarding the disposal of released waste radionuclides because of their volatility and long half-life. The release of radioactive isotopes of iodine from uranium fission reactions is a challenge. Although various adsorbents have been explored for the uptake of iodine, there is still interest in novel adsorbents. The novel adsorbents should be synthesized using reliable and economically feasible synthetic procedures. Herein, we discussed the state-of-the-art performance of various categories of porous organic materials including covalent organic frameworks, covalent triazine frameworks, porous aromatic frameworks, porous organic cages, among other porous organic polymers for the uptake of iodine. This review discussed the synthesis of porous organic materials and their iodine adsorption capacity and reusability. Finally, the challenges and prospects for iodine capture using porous organic materials are highlighted.

Analysis of factors influencing the clinical outcome after surgery and 131I therapy in patients with moderate-risk thyroid papillary carcinoma

PURPOSE

Generally, the prognosis for papillary thyroid cancer (PTC) is favorable. However, the moderate risk involved warrants further evaluation. Hence, we investigated the clinical outcomes in patients with moderate-risk PTC following surgery and the first ¹³¹I therapy, as well as the relevant factors that influence the therapeutic efficacy.

METHODS

Retrospective analyses of 175 patients with medium-risk PTC who visited the Second Affiliated Hospital of Chongqing Medical University from September 2017 to April 2019 were conducted. In according with the 2015 American Thyroid Association (ATA) guideline treatment response evaluation system, the patients were categorized into the following groups: excellent response (ER), indeterminate response (IDR), biochemical incomplete response (BIR), and structurally incomplete response (SIR), of which IDR, BIR, and SIR were collectively referred to as the NER group. To compare the general clinical features between the 2 groups of patients, 2 independent samples t-tests, χ² test, and Mann-Whitney U-test were performed, followed by multivariate logistic regression analyses. With reference to the receiver operating characteristic (ROC) curve, the predicted value of ps-Tg to ER was evaluated, and the best cut-off value was determined. The subgroups with BRAF^V600E test results were analyzed by χ2 test only.

RESULTS

The treatment responses of 123 patients were ER, while those of 52 patients were NER. The differences in the maximum tumor diameter (U = 2495.50), the amount of metastatic lymph nodes (U = 2313.50), the size of metastatic lymph node (U = 2113.50), the metastatic lymph node ratio (U = 2111.50), metastatic lymph node location (χ² = 9.20), and ps-Tg level (U = 1011.00) were statistically significant. Multivariate regression analysis revealed that ps-Tg (OR = 1.209, 95% CI: 1.120-1.305) was an independent variable affecting ER. The cut-off value of ps-Tg for predicting ER was 6.915 ug/L, while its sensitivity and specificity were 69.2% and 89.4%, respectively.

CONCLUSIONS

Patients with smaller tumor size, fewer lymph nodes, lower metastatic lymph node ratio, metastatic lymph nodes in the central region, smaller lymph node size, and ps-Tg <6.915 ug/L demonstrated better therapeutic effects after the initial treatment.

Urinary iodine concentration and radioactive iodine therapeutic response in patients with differentiated thyroid cancer

Aim: Urinary iodine concentration (UIC) may assess radioactive iodine ablation. Materials & methods: According the 2015 American Thyroid Association guidelines, patients were categorized into low- to intermediate-risk or high-risk groups. The iodine concentration in the morning urine specimens was measured by the ceric ion-arsenious acid method. Results: In the low- to intermediate-risk group (113 cases), nonexcellent response (non-ER) was associated with higher UIC, higher UIC subgroups (p < 0.05), higher pre-ablative stimulated thyroglobulin levels (p < 0.01). In the high-risk group (68 cases), the non-ER rate was higher in the higher pre-ablative stimulated thyroglobulin group (p < 0.01), but not significantly different between the UIC and UIC subgroups (p > 0.05). Conclusion: The non-ER rate was related to UIC in the low- to intermediate-risk group; however, UIC did not affect the non-ER rate in the high-risk group.

Blood prognostic predictors of treatment response for patients with papillary thyroid cancer

Background: Papillary thyroid cancer (PTC) is a very common malignant disease with high morbidity. We needed some pretreatment indicators to help us predict prognosis and guide treatment. We conducted a study about some pretreatment prognostic indicators.

Methods: This clinical study recruited 705 postoperative PTC patients (211 males, 494 females). Clinical data before radioactive iodine (RAI) treatment were collected. Patients’ response to therapy were classified into two categories: ‘Good Prognosis Group’ (GPG) and ‘Poor Prognosis Group’ (PPG), according to ‘2015 American Thyroid Association Guidelines’. Differences of indicators between different prognosis groups were compared. Odds ratios (ORs) were calculated by univariate/multiple binary logistic regression models. Difference of body mass index (BMI) changes before and after RAI treatment between different prognosis groups was also compared.

Results: A total of 546 (77.45%) belonged to GPG, and 159 (22.55%) belonged to PPG. Platelet (PLT), neutrophil (NEUT), PLT subgroups, and combination of red blood cell distribution width (RDW) and BMI (COR-BMI) were different between two prognosis groups. The significance of the difference between the two groups of BMI disappeared after the Bonferroni correction. PLT and PLT subgroups had detrimental effects on the risk of PPG; T stage had a positive effect on the risk of PPG. PLT subgroup showed a detrimental effect on the risk of PPG when we included additional covariates.

Conclusions: We found that lower pretreatment PLT levels may indicate a poor prognosis for PTC. The relationship between platelet-derived growth factor (PDGF) and radiation sensitivity may be the key to this association.

The Prognostic Role of Postablative Non-Stimulated Thyroglobulin in Differentiated Thyroid Cancer

Simple Summary

In the management of patients with differentiated thyroid cancer, thyroglobulin (Tg) is used as a tumor marker to predict residual disease. After surgery, the presence or absence of persistent disease and the risk for recurrent disease should be assessed. Risk categories may be changed during the course of disease; the reclassification of patients influences the management of the disease and the intensity of follow-up. The diagnostic and prognostic roles of postoperative stimulated and one-year postablative non-stimulated Tg was evaluated. The individual lowest and highest non-stimulated Tg values during the entire follow-up were also assessed. Non-stimulated Tg values had excellent diagnostic accuracy in predicting structural disease, and the risk classification based on these was significantly more accurate regarding outcome than that based on the postoperative stimulated Tg. Analysis of the lowest and highest Tg values highlighted that a patient’s risk category can be revised based on a single Tg measurement.

Abstract

Thyroglobulin (Tg) is the most important tumor marker in differentiated thyroid cancer (DTC). The aim of this study was to assess the diagnostic and prognostic roles of postoperative stimulated and postablative lowest, highest, and one-year non-stimulated Tg values obtained during the follow-up of patients with DTC. In this retrospective study, 222 radioiodine-treated, anti-thyroglobulin antibody (TgAb)-negative DTC patients having at least 9 months’ follow-up time were included (172 papillary and 50 follicular cancers; median age: 48 (from 15 to 91) years; female–male ratio: 158/64; median (quartiles) follow-up time: 54 (22–97) months). The 2015 American Thyroid Association guidelines were applied as criteria of the therapeutic response. Postoperative stimulated Tg values had significantly lower diagnostic accuracy than any of the non-stimulated postablative Tg values. One-year non-stimulated Tg had excellent prognostic value for structural disease: a cut-off value of 0.85 ng/mL had an 88.1% diagnostic accuracy. If the Tg value did not decrease below 0.75 ng/mL at any time during follow-up, the risk of residual disease was 25 times higher. The highest non-stimulated Tg during follow-up was the best predictor of residual disease (e.g., a Tg value exceeding 7.7 ng/mL indicated a 30-fold increase in risk). Non-stimulated Tg values measured during follow-up have excellent diagnostic accuracy to predict structural disease in DTC patients. The risk classification of a patient can safely be modified based on even a single Tg measurement.

Prognostic value and dynamics of antithyroglobulin antibodies for differentiated thyroid carcinoma

Background: The clinical value of antithyroglobulin antibodies (TgAb) as a tumor marker for differentiated thyroid cancer (DTC) is still controversial. Materials & methods: We studied 110 TgAb positive DTC patients who underwent total thyroidectomy and ¹³¹I therapies. Multivariate logistic regression was conducted to analyze the association between prognostic factors and disease outcomes. Results & conclusion: Pre-ablation TgAb levels and the changes of TgAb in 6-12 months after the first ¹³¹I therapy were risk factors for disease outcome in patients younger than 55, while extrathyroid extension was a risk factor in patients older than 55. The median TgAb half-life was 7.7 months and the median time for TgAb positivity to become negative was 15.8 months. The dynamics of TgAb within the first year after remnant ablation could predict disease outcome for DTC patients.

Outcomes following I-131 treatment with cumulative dose exceeding or equal to 600 mCi in differentiated thyroid carcinoma patients

To evaluate treatment outcomes following radioactive iodine (RAI) treatment with a cumulative dose of ≥≥600 mCi in differentiated thyroid carcinoma (DTC) patients, a retrospective review of medical records was done in 176 DTC patients with a cumulative dose of ≥600 mCi from January 1993 to December 2013. All patients were followed up for at least 2 years after receiving 600 mCi of I-131 treatment. Remission criteria were no clinical and imaging evidence of disease and low serum thyroglobulin levels during thyroid-stimulating hormone suppression of <0.2 ng/ml or of <1 ng/ml after stimulation in the absence of interfering antibodies. A total of 176 patients were included in the study: 137 - papillary thyroid cancer, 29 - follicular thyroid cancer, 9 - mixed papillary and follicular thyroid cancer, and 1 - Hurthle cell carcinoma. Most of the patients (118, 67%) had locoregional metastasis, whereas 48 patients (27%) had distant metastases at presentation. The median cumulative dose was 900 mCi (range: 600-2200 mCi). The mean follow-up period was 82.84 ± 42.41 months. Only 16 patients (9.1%) met remission criteria at the end of treatment. The rest of patients (160, 90.9%) were not remitted: stable disease in 94 (53.4%), at least 1 metastasis without I-131 uptake in 34 (19.3%), progressive disease in 21 (11.9%), and death during the whole follow-up period in 11 (6.3%). Two patients (1.1%) developed second primary malignancy. Eighteen cases were suspected of bone marrow suppression (14 cases [7.9%] had anemia and 5 cases [2.8%] had neutropenia). Seven patients (3.9%) developed permanent salivary gland dysfunction. Although the complications after receiving RAI treatment with a cumulative dose of ≥≥600 mCi were low and not severe, the patients with remission were in <10%. Our study suggests that the decision to administer further treatments should be made on an individual basis because beneficial effects may be controversial.

The impact of radioactive iodine treatment on survival among papillary thyroid cancer patients according to the 7th and 8th editions of the AJCC/TNM staging system: a SEER-based study

Papillary thyroid cancer is a very common endocrine malignancy. The 8th American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) staging system introduced major changes. We conducted this retrospective cohort analysis to assess the benefits of radioactive iodine (RAI) according to different stratification of patients. The source of the data was the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. From 2006 to 2015, patients with papillary thyroid cancer were included in our study. The interactions between different variables and RAI treatment were tested by multivariate Cox regression models to compare the survival differences according to RAI treatment between the patients assessed with the 7th and 8th edition of the AJCC/TNM staging system. The results of the interaction analysis and group comparisons indicated that the effects of RAI treatment on patients staged with the 7th and 8th editions were similar. Patients with early Stage, early T stage, N0 and subtotal or near total thyroidectomy benefited greatly from RAI treatment. Patients with Stage III according to the 8th edition benefited less from RAI than patients with Stage III according to the 7th edition. Patients with T1a benefited from RAI but benefited less than patients with other T stages. Patients with T3a benefited more from RAI than those with T3b. According to the 8th edition, Stage III/IV more accurately differentiates patients with advanced stage disease. These patients benefitted less from RAI treatment, which may be due to the relatively weaker iodine uptake by tumor cells. T1a patients benefitted less than patients with other T stages. The difference in RAI benefit between patients with T3a and T3b is a novel finding in our study.

Negative remnant 99mTc-pertechnetate uptake predicts excellent response to radioactive iodine therapy in low- to intermediate-risk differentiated thyroid cancer patients who have undergone total thyroidectomy

OBJECTIVE

Negative ^99mTc-pertechnetate uptake of the thyroid bed indicates the absence or a small volume of remnant thyroid tissue (RTT) after total thyroidectomy (TT). The aim of this study is to evaluate the predictive value of negative ^99mTc-pertechnetate scintigraphy for excellent response (ER) to radioactive iodine therapy (RIT) in low- to intermediate-risk differentiated thyroid cancer (DTC) patients.

PATIENTS

One-hundred and eighty-nine low- to intermediate-risk DTC patients who underwent TT, RIT with a single dose of 30 mCi and suppressive therapy with thyroid-stimulating hormone (TSH) from July 2015 to February 2016 in our hospital were retrospectively evaluated. ^99mTc-pertechnetate thyroid scintigraphy was performed just before RIT and images were reported dichotomously as negative or positive. The response of patients was assessed for 23.2 ± 3.8 months after RIT and dichotomized as excellent response (ER) or non-excellent response (NER). ^99mTc-pertechnetate uptake, age at diagnosis, gender, multifocality, T stage, N stage, preablative stimulated thyroglobulin (ps-Tg), and TSH were explored as potential predictors for ER.

RESULTS

80.68% (71/88) of patients with negative ^99mTc-pertechnetate uptake achieved ER. When patients were evaluated according to different ps-Tg levels, we found that 94.83% (55/58) of patients with ps-Tg < 1 ng/ml and negative ^99mTc-pertechnetate uptake achieved ER. Multivariate Cox regression analysis revealed that ps-Tg (P = 0.0001) and ^99mTc-pertechnetate uptake (P = 0.0473) were independent predictors for ER.

CONCLUSIONS

In addition to ps-Tg, negative ^99mTc-pertechnetate uptake is also a significant independent predictor for an excellent response in low- to intermediate-risk patients. It may be possible to omit RIT in patients with ps-Tg < 1 ng/ml and concurrent negative ^99mTc-pertechnetate uptake.

Changes of serum midkine as a dynamic prognostic factor to monitor disease status in papillary thyroid cancer

This study aimed to investigate the value of dynamic changes of midkine (MK) to monitor post-surgical patients with papillary thyroid cancer (PTC) who were managed with I therapies.MK concentration at initial I ablation therapy (MK1) as well as 10 to 12 months thereafter (MK2) was evaluated. And the dynamic changes of thyroglobulin (Tg) were compared (Tg1 and Tg2). Patients with MK influencing co-morbidities and with positive thyroglobulin antibodies were excluded. Concentrations of MK were measured by enzyme-linked immunosorbent assay.There were 241 PTC patients (36 males, 205 females) enrolled, 55 cases had metastases (8 males, 47 females) during their follow-up. Cox regression showed if Tg2 decreased (compared with Tg1), but not to less than 1.0ng/mL under TSH stimulation, the risk of metastases was 12.554 times more than if it could decrease to the optimal level. If Tg2 increased, the risk is 19.461 times higher. As for MK, if MK2 level decreased (compared with MK1), but not to a normal level, the risk of metastases is 3.006. If MK2 level increased, it would be 5.030 likely to had metastases.Our results indicated that MK could potentially be used as a disease monitoring biomarker for PTC, although inferior to Tg.

Radioprotective effect of vitamin E on salivary glands after radioiodine therapy for differentiated thyroid cancer: a randomized-controlled trial

OBJECTIVES

This study aimed to examine the radioprotective effect of vitamin E on salivary glands after radioactive iodine (I) therapy in patients with differentiated thyroid cancer.

PATIENTS AND METHODS

Eighty-two patients with differentiated thyroid cancer were enrolled in this study. They were divided randomly into four groups (control group: 22 cases, group A: 23 cases, group B: 22 cases, and group C: 15 cases) before postsurgical ablation therapy with 100 mCi I. The patients in groups A, B, and C received vitamin E 100, 200, and 300 mg/day orally, respectively, for a duration of 1 week before to 4 weeks after I therapy. Salivary gland function was assessed using salivary gland scintigraphy immediately before and 6 months after I therapy. Uptake fraction (UF), uptake index (UI), excretion fraction (EF), and excretion ratio (ER) of each salivary gland were measured and compared.

RESULTS

On comparison between before and after I therapy in the control group, there was a significant decrease in UF of both right and left parotid glands (all P<0.01). In group A, a significant increase in EF of the right parotid gland (P<0.01) and UI of the right submandibular gland (P<0.05) was found. In group B, there was a significant increase in UI of the right parotid gland and both submandibular glands (all P<0.01). In group C, there was a significant increase in UF of the left parotid gland (P<0.05) and the right submandibular gland (P<0.01). Also, there was a statistical increase in UI in both submandibular glands (all P<0.01). However, on comparing the changes in the post-I therapy salivary scintigraphy parameters among the four groups, there was a significant difference in ΔUI of the right parotid gland (P<0.05) and both submandibular glands (all P<0.01), as well as ΔER of the left parotid gland (P<0.05) and ΔUF of the left submandibular gland (P<0.05).

CONCLUSION

Vitamin E exerts significant protective effects on the parotid and submandibular glands after I therapy.

Double-layer carbon nanocapsules with radioiodine content and its interaction with calcium, phosphorus, and strontium

First principles calculations have been performed for C₆₀@C₁₈₀ carbon double-layer endofullerenes with up to: three diatomic radioiodine molecules (¹³¹I₂), two potassium radio-iodide (K¹³¹I), and three sodium radio-iodide (Na¹³¹I) inside. The plane-wave pseudopotential (PP) method within the general gradient approximation (GGA) in the framework of the density functional theory (DFT) and time-dependent DFT (TD-DFT) was used to perform geometric optimizations (GOs) and molecular dynamics (MD) at 310 K and atmospheric pressure. We found that the double-layer carbon nanocapsules formed by two concentric fullerenes (C₁₈₀ surrounding C₆₀) are very stable and may contain a radiodosis, without altering their configuration; that is, the 3(¹³¹I₂)@C₆₀@C₁₈₀, 2(K¹³¹I)@C₆₀@C₁₈₀, and 3(Na¹³¹I)@C₆₀@C₁₈₀ systems constitute stable nanocapsules. We analyzed the interaction of double-layer endofullerene with radioactive content with some calcium, phosphorus, and strontium atoms, [n(X¹³¹I)@C₆₀@C₁₈₀ + mY], for X = I, K, Na; Y = Ca, P, Sr; n = 1, 2, 3; m = 1, …, 20. Our calculations show that up to m = 20 calcium atoms can easily be physisorbed by the outer surface of the double-layer endofullerene, maintaining their integrity and shielding the radiodosis of any interaction that can proceed from the outside. It is thus concluded that these double-layer endofullerenes can be functionalized as vectors to deliver radiodosis with structural advantages over the single layer systems; as they are more robust, stable, and possess a larger surface to functionalize with some atoms serving as molecular recognizers. Graphical abstract Double-layer carbon nanocapsules with radioiodine content and its interaction with calcium, phosphorus and strontium.

Effects of first radioiodine ablation on functions of salivary glands in patients with differentiated thyroid cancer

The aim of this study was to evaluate the effects of the first radioactive iodine (I) therapy on functions of salivary glands in patients with differentiated thyroid carcinoma (DTC).There were 36 consented patients with DTC enrolled in this study, who received 3.7 GBq (100mCi) I for ablation after total thyroidectomy. Salivary gland function was assessed using salivary gland scintigraphy in two phases, one 4 hours before and the other 6 months after I therapy (both under thyrotropin stimulation condition). Quantitative parameters including uptake fraction (UF), uptake index (UI), excretion fraction (EF), and excretion ratio (ER) were measured and compared. Blood parameters were also compared. Associations between sex and outcome of the first I therapy as well as individual salivary gland function were measured. Wilcoxon Signed Rank Sum test and χ test were used for statistical analysis.When compared between pre-ablation and post-ablation, UF of bilateral parotid and submandibular glands were significantly increased (all P < .01). UI of both submandibular glands were significantly increased (P < .05). This seemingly increased uptake function after the first I therapy was actually compensatory mechanism of salivary gland, which indicated a possible intermediate state after radiation. But salivary glands' secretory function had not changed significantly except for left submandibular gland; we demonstrated that only left submandibular gland showed significantly decreased ER (P < .05). Thyroglobulin and thyroglobulin antibody significantly decreased after I therapy (P < .05). There were no sex differences on therapeutic outcome and salivary gland dysfunctions after the first I therapy. Salivary gland of both males and females could be affected by I therapy.The first I ablative therapy may impair the salivary uptake and secretory function of patients with DTC. There was no association between sex and salivary gland dysfunction.

Serum midkine as a surrogate biomarker for metastatic prediction in differentiated thyroid cancer patients with positive thyroglobulin antibody

Serum thyroglobulin (Tg) is the main post-operative tumor biomarker for patients with differentiated thyroid cancer (DTC). However, the presence of thyroglobulin antibodies (TgAb) can interfere with Tg level and invalidate the test. In this study, we aimed to investigate the predicative value of midkine (MK) as a cancer biomarker for DTC patients with positive TgAb before the first ¹³¹I therapy. MK levels were measured by enzyme-linked immunosorbent assay in 151 recruited DTC patients after exercising strict inclusion and exclusion criteria. There were 28 TgAb positive DTC patients with metastases and 123 DTC patients without metastases. The value of pre-¹³¹I-ablative MK to predict metastasis was assessed by receiver operating characteristic (ROC) curves in these two groups of patients. MK levels in the TgAb positive DTC patients were significantly higher than the DTC patients without metastases. ROC showed good predictability of MK, with an area under the curve of 0.856 (P < 0.001), and a diagnostic accuracy of 83% at the optimal cut-off value of 550 pg/ml. In conclusion, we show that MK can potentially be used as a surrogate biomarker for predicting DTC metastases when Tg is not suitable due to TgAb positivity.