Analysis of risk factors for papillary thyroid carcinoma and the association with thyroid function indicators.

Objective: This study aims to analyze the relationship between papillary thyroid carcinoma (PTC) and various factors. Methods: The study involved two groups-PTC patients and non-PTC controls. We utilized binary logistic regression and Least Absolute Shrinkage and Selection Operator (Lasso) regression for variable selection and risk factor analysis. Correlation analysis was performed using Spearman's rank correlation. The diagnostic value of thyroid stimulating hormone (TSH) levels for PTC was assessed using Receiver Operating Characteristic (ROC) curves. Results: PTC patients exhibited higher body mass index (BMI) (23.71 vs. 22.66, p<0.05) and TSH levels (3.38 vs. 1.59, p<0.05). Urinary iodine concentration (UIC) was an independent predictor of PTC (OR=1.005, p<0.05). The optimal TSH threshold for PTC diagnosis was 2.4 mIU/L [The Area Under the Curve (AUC)=67.3%, specificity=71.4%, sensitivity=70.1%]. TSH levels positively correlated with BMI (r=0.593, p<0.05) and UIC (r=0.737, p<0.05). Conclusions: UIC may be an independent predictor of PTC, and TSH levels have some diagnostic value for identifying PTC.

Analysis of Urinary Iodine Concentration in Differentiated Thyroid Cancer and Breast Cancer Cases.

Iodine intake can affect thyroid and breast cells, and urinary iodine concentration (UIC) is an effective biomarker for iodine intake. OBJECTIVES: This study aimed to analyze the correlation between urinary iodine concentration in differentiated thyroid cancer (DTC) and breast cancer (BC) subjects. METHODS: The study consisted of 80 subjects divided into case (20 DTC and 20 BC subjects) and control (40 subjects). Morning urine or spot urine was used for UIC measurement. RESULTS: In thyroid cancer, UIC median patients and controls were 195.45 ± 133.61 µg/L and 145 ± 39.64 µg/L, respectively, with p =0.33. The UIC median of PTC subjects was significantly higher compared to FTC subjects, 227.12±130.98 µg/L versus 68.75±22.95 µg/L, p=0.00, and papillary thyroid cancer is closely related to a high iodine excretion in urine with contingency coefficient  (c)=0.722. In BC patients, regardless of subtypes, breast cancer subjects showed a significantly lower iodine excretion level. The median of UIC patients and controls were 80.05 ± 38.24 µg/L and 144.25 ± 36.79 µg/L, respectively, p=0.000. CONCLUSIONS: Iodine urine concentrations strongly correlate with the type of DTC histopathology, and in BC subjects, IUC was significantly lower compared to the control.

Long-Term Changes of Urinary Exosomal Peptide Levels After Thyroidectomy in Patients with Thyroid Cancer: A Prospective Observational Study.

Background: The recurrence rate of thyroid cancer can be as high as 30%. The purpose of this study was to examine changes of urine exosomal peptide levels after thyroidectomy in patients with thyroid cancer to determine if levels can predict the risk of recurrence. Methods: Patients >20 years old as newly diagnosed with papillary thyroid cancer who had received a thyroidectomy were recruited. Urine samples were collected at 12 months after enrollment to the study, and 1 year later. Urine exosomes containing different peptides were identified and compared. Results: A total of 70 patients were enrolled in the study, and were classified by the interval between surgery and enrollment: 42 patients with < 5 years between surgery and enrollment, 14 patients between 5-10 years, and 14 patients longer than 10 years. No recurrence was observed in any patient during the 2 years after enrollment. No significant differences were found in the levels of serum proteins or urine exosomal peptides between groups, or between intervals. Known risk factors for high-risk thyroid cancer had only a mild correlation with serum protein levels and urine exosomal peptides. Conclusion: Our study revealed the long-term basal fluctuation ranges of serum proteins and urine exosomal peptides in patients with thyroid cancer who underwent thyroidectomy. For high-risk patients after thyroidectomy, concentrations of serum proteins or urine exosomal peptides within the ranges may indicate there is a lower risk of thyroid cancer recurrence during long-term follow-up. Trial Registration: ClinicalTrials.gov: NCT03488134.

Associations between essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid cancer.

Aim of this study was to evaluate the association between multiple essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid carcinoma (PTC). The concentrations of 10 essential microelements in urine [cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), strontium (Sr), zinc (Zn), and iodine (I)] were measured in 608 patients newly diagnosed with PTC, including 154 males and 454 females. Chi square test and Wilcoxon rank sum test were used to compare general characteristics among males and females. Multivariate logistic regression was used to evaluate the associations between essential microelements and PTC clinicopathologic characteristics in single- and multi-microelement models. In this study, we only observed that the frequency of lymph node metastasis in males was higher than in females, and males had higher levels of zinc than females, but males had lower levels of iodine than females. It was found that high levels of Fe were associated with decreased risk of PTC tumor size > 1 cm, capsular invasion, and advanced T stage (T3/4a/4b). High levels of Co and Mo were associated with decreased risk of capsular invasion and lymph node metastasis, respectively. However, high levels of Mn and Sr were associated with increased risk of capsular invasion and multifocality respectively, and both were associated with increased risk of advanced T stage (T3/4a/4b). These findings indicated that certain essential microelements might have potential effects on PTC progression and aggressiveness. Further studies are required to confirm these findings.

Potential role of iodine excess in papillary thyroid cancer and benign thyroid tumor: A case-control study.

BACKGROUND AND OBJECTIVES: The relationship between nutritional status of iodine and thyroid tumor is unclear. We investigated the association between urinary iodine concentration and thyroid function in patients with papillary thyroid cancer, benign thyroid tumor and healthy individuals. METHODS AND STUDY DESIGN: We compared the biomarkers of thyroid function and urinary iodine concentration within and between each group. A regression analysis was used to identify risk factors for papillary thyroid cancer. Correlation analysis was performed to determine whether any significant correlation exists between urinary iodine concentration and thyroid function biomarkers. RESULTS: The iodine nutrition statuses of these three groups were adequate (median urinary iodine concentration= 100-199 µg/L). However, the median urinary iodine concentration of papillary thyroid cancer (174.7 µg/L) and benign thyroid tumor (165.04 µg/L) groups was significantly higher than that of the healthy control group (135.8 µg/L) (p<0.05). The regression analysis showed that thyroglobulin antibody was an independent risk factor for papillary thyroid cancer. After adjusting for age and gender, the association between thyroglobulin antibody and urinary iodine concentration was significant (ß: 0.002; p<0.05). In subgroup analyses, significant correlations was noted only in the papillary thyroid cancer group (adjusted ß: 0.002; 95% confidence interval: 0.000- 0.003). CONCLUSIONS: Excessive iodine in patients with thyroid tumors may affect thyroglobulin antibody, which may be an independent risk factor for papillary thyroid cancer.

Associations of urinary phthalate metabolites with risk of papillary thyroid cancer.

Some studies have revealed thyrotoxicity of phthalates; however, associations of phthalate exposure with papillary thyroid cancer (PTC) remain unclear. We conducted a pair-matching case-control study of 111 PTC cases and 111 age- and sex-matched non-PTC controls to examine associations between urinary concentrations of phthalate metabolites and PTC. Phthalate metabolites were determined in fasting urine specimens by ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS). After adjusting for potential confounders and other phthalate metabolites, the concentrations of the sum of di (2-ethylhexly) phthalate (DEHP) metabolites in urine were positively associated with PTC [odds ratio (OR) = 5.35; 95% confidence interval (CI): 1.61-17.83], suggesting the effect of phthalates exposure on PTC development. The findings require confirmation.

Association of exposure to multiple metals with papillary thyroid cancer risk in China.

Papillary thyroid cancer (PTC) has inflicted huge threats to the health of mankind. Metal pollution could be a potential risk factor of PTC occurrence, but existing relevant epidemiological researches are limited. The current case-control study was designed to evaluate the relationships between exposure to multiple metals and the risk of PTC. A total of 262 histologically confirmed PTC cases were recruited. Age- and gender-matched controls were enrolled at the same time. Urine samples were used as biomarkers to reflect the levels of environmental exposure to 13 metals. Conditional logistic regression models were adopted to assess the potential association. Single-metal and multi-metal models were separately conducted to evaluate the impacts of single and co-exposure to 13 metals. The increased concentration of urinary Cd, Cu, Fe, and Pb quartiles was found significant correlated with PTC risk. We also found the decreased trends of urinary Se, Zn, and Mn quartiles with the ORs for PTC. These dose-response associations between Pb and PTC were observed in the single-metal model and remained significant in the multi-metal model (OR25-50th=1.39, OR50-75th=3.32, OR>75th=7.62, p for trend <0.001). Our study suggested that PTC was positively associated with urinary levels of Cd, Cu, Fe, Pb, and inversely associated with Se, Zn, and Mn. Targeted public health policies should be made to improve the environment and the recognition of potential risk factors. These findings need additional studies to confirm in other population.

Urinary iodine is increased in papillary thyroid carcinoma but is not altered by regional population iodine intake status: a meta-analysis and implications.

Excessive iodine intake has been associated with increased risk of thyroid cancer (TC) in many studies, but the results have not been consistent. Since it was common knowledge that urinary iodine (UI) is considered a sensitive marker of current iodine intake, we conducted a meta-analysis to clarify the association between high UI and TC. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, and the Cochrane Collaboration. Between-group meta-analyses were performed to compare UI between TC patients and the healthy/euthyroid subjects in local residents and benign thyroid nodules (BTN) patients. Then, between-group meta-analyses to compare the incidence rate of iodine excess were also conducted. The 22 case-control studies included in the meta-analyses represented 15,476 participants. It is the first time to clarify that UI was increased in PTC patients, but was not altered by regional population iodine intake status. Compared with BTN patients, PTC patients exhibited both higher UIC and higher odds ratio of iodine excess only in adequate iodine intake status subgroup; UIC, not the odds ratio of iodine excess, was higher in patients with PTC than those with BTN in above requirements iodine intake subgroup. A novel insight is offered that high UI in PTC patients was less influenced by regional population iodine intake status. It is indicted that high iodine intake is not a risk factor for PTC and high urinary iodine is just a specific characteristic of the disease.

A case-control study of urinary levels of iodine, perchlorate and thiocyanate and risk of papillary thyroid cancer.

BACKGROUND: The incidence of thyroid cancer has recently increased worldwide. With the exception of radiation exposure, the effects of potential risk factors on thyroid cancer incidence remain controversial. OBJECTIVES: The association between exposure to iodine, perchlorate, and thiocyanate and papillary thyroid cancer (PTC) incidence was evaluated and risk factors were predicted. METHODS: A pair-matching case-control study was performed including 116 age- and sex-matched PTC cases and 116 non-PTC controls. Iodine, perchlorate, and thiocyanate concentrations in urine specimens were determined by inductively coupled plasma mass spectrometry and ultra-performance liquid chromatography-tandem mass spectrometry. The association between iodine, perchlorate, and thiocyanate urinary concentrations and PTC was evaluated using univariable conditional regression logistic analysis followed by multivariable conditional logistic regression analyses with backward stepwise selection to predict risk factors for PTC. RESULTS: After adjusting for confounders and creatinine standardization, urinary concentrations of iodine [odds ratio (OR) = 11.01, 95% confidence interval (CI): 1.97-30.52] and perchlorate (OR = 2.27, 95% CI: 1.03-5.03) were associated with the risk of PTC, whereas urinary thiocyanate concentration showed a negative association (OR = 0.24, 95% CI: 0.09-0.65). CONCLUSIONS: Increased exposure to iodine and perchlorate may affect PTC development, whereas high thiocyanate exposure may have a beneficial effect.

A case-control study of exposure to organophosphate flame retardants and risk of thyroid cancer in women.

BACKGROUND: Growing evidence demonstrates that exposure to organophosphate flame retardants (PFRs) is widespread and that these chemicals can alter thyroid hormone regulation and function. We investigated the relationship between PFR exposure and thyroid cancer and whether individual or temporal factors predict PFR exposure. METHODS: We analyzed interview data and spot urine samples collected in 2010-2013 from 100 incident female, papillary thyroid cancer cases and 100 female controls of a Connecticut-based thyroid cancer case-control study. We measured urinary concentrations of six PFR metabolites with mass spectrometry. We estimated odds ratios (OR) and 95% confidence intervals (95% CI) for continuous and categories (low, medium, high) of concentrations of individual and summed metabolites, adjusting for potential confounders. We examined relationships between concentrations of PFR metabolites and individual characteristics (age, smoking status, alcohol consumption, body mass index [BMI], income, education) and temporal factors (season, year) using multiple linear regression analysis. RESULTS: No PFRs were significantly associated with papillary thyroid cancer risk. Results remained null when stratified by microcarcinomas (tumor diameter ≤ 1 cm) and larger tumor sizes (> 1 cm). We observed higher urinary PFR concentrations with increasing BMI and in the summer season. CONCLUSIONS: Urinary PFR concentrations, measured at time of diagnosis, are not linked to increased risk of thyroid cancer. Investigations in a larger population or with repeated pre-diagnosis urinary biomarker measurements would provide additional insights into the relationship between PFR exposure and thyroid cancer risk.