Increase In Risk Of Thyroid Cancer Research Articles

Thyroid gland cancer and insulin resistance: a modern view of the problem

Background. The impact of insulin resistance on the probability of increase in thyroid cancer risk has been drawing a lot of attention of researchers lately. This problem is far from being completely solved. Studying this interrelationship may influence the effectiveness of the treatment of the mentioned widespread pathology.
 Purpose – to review present literature sources on research of interrelationship between insulin resistance and thyroid cancer, and also possible mechanisms of this relationship.
 Materials and methods. Literature search was performed manually by the keywords (thyroid cancer, insulin resistance, IGF-1, IGF-2, abdominal obesity, increase in body mass index, metformin), and also literature sources from evidential data bases PubMed, Web of Science were reviewed. Metaanalyses, systematic reviews and cohort studies were also taken into account. 148 literature sources were studied in total. The sources, which had been published within the last 10 years, were preferably selected.
 Results. Insulin resistance is viewed as an important independent factor of development of numerous malignancies. The carcinogenic activity of insulin resistance is caused by the resistance itself, as well as by the metabolic disorders related to it. It has been established that excessive weight and obesity are to a great extent attributed to more aggressive clinical pathological signs of thyroid cancer. Recent research showed a larger volume of thyroid and higher risk of knot forming in patients with insulin resistance. Thus, thyroid cancer is one of the main factors of thyroid transformation. Therapeutic methods of eliminating metabolic syndrome and associated hormonal diseases for prevention and therapy of oncologic diseases are drawing ever-greater scientific interest. The anti-tumor features of metformin and its capability of retarding carcinogenesis are shown in the studies.
 Conclusions. The given literature analysis has proved that the problem of treating malignant thyroid tumors and their metastasis is caused not only by morphological, cellular and molecular-biological features of the tumor itself, but also by insufficient knowledge about the interrelationship between insulin resistance, abdominal obesity, increase in body mass index, high-calorie diet and reduction of consumption of polyunsaturated fats, harmful impact of environment with molecular changes, specific for thyroid cancer. It is confirmed by a significant increase in thyroid cancer rate, especially papillary histotype, alongside with an increase in obesity rate. The studying of possibilities of decreasing incidence and mortality rates of oncologic pathology when using medications, which stabilize insulin and contribute to a decrease in degree of hyperinsulinemia, one of which is metformin, generates profound interest

The associations between thyroid-related hormones and the risk of thyroid cancer: An overall and dose-response meta-analysis.

Thyroid cancer (TC) is one of the most common malignant tumours of the endocrine system. Thyroid-stimulating hormone (TSH) is known as being a risk factor for TC, but other thyroid-related hormones are inconsistently associated with TC. The purpose of this study was to comprehensively evaluate the relationships between thyroid-related hormones and the risk of TC. This study utilized searches of PubMed, Embase, Web of Science and Cochrane library up to the date of March 31st, 2022. Additionally, we performed a systematic review of related original studies combining overall and dose-response meta-analyses. A total of 30, 5 and 7 articles were included in the meta-analyses of TSH, Free triiodothyronine (FT3), free thyroxine (FT4) and TC risk with 58437, 6813 and 7118 participants respectively. An increased risk of TC was associated with high TSH exposure (OR=1.28, 95% CI: 1.19-1.37, P < 0.001) in the overall meta-analysis. For every 1 mU/L increase in TSH, the risk of TC increased by 16%. However, in those studies that used healthy subjects as controls, the association was not statistically significant(P=0.62). Additionally, high serum FT3 demonstrated a reduced risk of TC, with a combined OR of 0.86 in the fixed-effect model (95% CI: 0.81-0.90, P < 0.001). In addition, a statistically significant increase in TC risk was found when FT4 concentrations reached a certain threshold (approximately 2.2 ng/dL) in the dose-response meta-analysis. Significant associations between thyroid-related hormones and the risk of TC were found in this study. Further research is needed to understand the underlying mechanisms.

Rotating night shift work, sleep and thyroid cancer risk in the Nurses’ Health Study 2

Background and aim Thyroid cancer is the most common endocrine malignancy with rising incidence worldwide. We prospectively evaluated whether rotating night shift work and sleep disturbances are associated with incident thyroid cancer risk in the Nurses’ Health Study 2 (NHS2). Methods We assessed rotating night shift work (&amp;#x2265;3 nights/month) history (cumulative number of years) at baseline and throughout follow-up (1989-2015) and sleep duration and sleep difficulty in 2001. Cox proportional hazard models, adjusted for potential confounders were used to calculate thyroid cancer hazard ratios (HR) and 95% confidence intervals (CI) for shift work history (0.1-4.9yrs, 5-9.9yrs, 10+yrs), sleep duration (&amp;#x2264;5, 6, 7, 8, &amp;#x2265;9hours) and difficulty falling or staying asleep (little or none of the time, sometimes, most or all of the time). We further stratified the analyses of night shift work by sleep characteristics. Results We identified 588 incident cases among 114,534 women. We observed no association between night shift work history and thyroid cáncer risk (1-4.9 years: HR 1.19, 95% CI 0.98, 1.44; 5-9.9 years: HR 1.13 95% CI 0.86, 1.48; &amp;#x2265;10 years: HR 1.10, 95% CI 0.78, 1.54; Ptrend=0.55). Sleep difficulty was suggestively associated with higher incidence of thyroid cancer when reported sometimes (HR 1.26, 95% CI 0.95, 1.67) and most or all the time (HR 1.35, 95% CI 1.00, 1.81; Ptrend=0.03), compared to little or none of the time. Participants with &amp;#x3e;10 years of night shift work and &amp;#x2264;6 hours of sleep had a 2-fold increase in thyroid cancer risk (HR 2.23; 95%CI, 1.08-4.06). Shift workers with &amp;#x3c;5 years of shift work and frequent sleep difficulty had an increased risk of thyroid cancer (HR 1.95; 95% CI 1.03, 3.67). Conclusion We found evidence that rotating night workers with frequent sleep difficulty or short sleep had an increased risk of thyroid cáncer. Keywords night work, thyroid cancer

Effect of the Interaction Between Cadmium Exposure and CLOCK Gene Polymorphisms on Thyroid Cancer: a Case-Control Study in China.

The exposure to endocrine disruptors and the disruption of the circadian rhythms can both affect thyroid hormones, with results that are most likely carcinogenic in humans. The effects of cadmium (Cd) level and circadian-related single-nucleotide polymorphisms (SNPs) on thyroid cancer (TC) risk have rarely been reported. In this study, the associations of urine Cd, CLOCK gene polymorphisms, and TC risk were evaluated, in addition to the effect of the gene-environment interaction on TC risk. In this case-control study, 218 TC cases and 218 controls were enrolled. Cd in urinary samples was determined by atomic absorption spectrometry. Three SNPs (rs3805151, rs3805154, and rs78929565) were genotyped with an improved multiplex ligation detection reaction technique. The individuals with a high Cd level were 1.72-fold more likely to have TC (OR = 1.72, 95%CI 1.04-2.85), and a high Cd level was associated with higher tumor T stage and N stage (OR = 2.42, 95%CI 1.28-4.58; OR = 3.26, 95%CI 1.67-6.33, respectively). Individuals with TT genotype of rs78929565 had a 107 % increase in TC risk (OR = 2.07, 95%CI 1.00-4.29). Cases with CT genotype tended to have a higher AJCC stage (OR = 2.79, 95% CI 1.01-7.78). A significant interaction was detected between the rs78929565 variant and Cd exposure (p interaction = 0.04). The TT genotype carriers of rs78929565 with a high Cd level were more susceptible to thyroid cancer than the major homozygotes carriers who were exposed to a low cadmium level (OR = 2.66, 95%CI 1.07-6.59). These findings suggested that Cd exposure and the CLOCK variant genotypes were associated with TC risk and tumor severity. Individuals with minor allele of rs78929565 and higher Cd exposure had increased susceptibility to TC. Further studies are required to confirm these findings.

Haplotype Based Analysis of XRCC3 Gene Polymorphisms in Thyroid Cancer

Background/Aims: In mammalian cells, XRCC3 plays an important role in the DNA double-strand breaks (DSBs) repair by homologous recombination. Genetic polymorphisms in XRCC3 gene may potentially affect the repair of DSBs and thus confer susceptibility to thyroid cancer. In this study, we used a haplotype-based approach to investigate whether 5 selected SNPs i.e. rs1799796, rs1799794, rs861539, rs709399 and rs861530 of XRCC3 gene are associated with thyroid cancer risk in 456 cancer patients and 400 cancer-free controls. Methods: Genotyping was performed using Allele-specific PCR followed by sequencing. Statistical analysis was performed to analyse gene and haplotype association. Results: After analysis, frequency of mutant genotype/alleles of SNPs (rs1799796, p<0.0001; rs1799794, p<0.0001; rs861539, p<0.001; rs709399, p <0.0001; rs861530, p<0.002) was found significantly higher in thyroid cancer patients compared to controls. Significant associations were found for most of the variant genotypes in SNPs of rs1799794, rs1799796, rs861539, rs861530 and rs709399 in papillary thyroid and follicular cancer patients compared to other histologic subtypes of thyroid carcinoma. Additionally, haplotype analysis revealed that haplotypes, AACGA (p= 0.0005), AGTAA (p= 0.008), GATAA (p= 0.001), GGCAA (p= 0.001) were linked with significant increase in thyroid cancer risk. However, haplotype AGCGG (p= 0.0009) was associated with a significant reduced thyroid cancer risk. Conclusion: Our results suggest that common genetic variants in the XRCC3 gene of DSBR pathway may modulate thyroid cancer risk.

Randomization to screening for prostate, lung, colorectal and ovarian cancers and thyroid cancer incidence in two large cancer screening trials.

BackgroundThyroid cancer incidence has increased significantly over the past three decades due, in part, to incidental detection. We examined the association between randomization to screening for lung, prostate, colorectal and/or ovarian cancers and thyroid cancer incidence in two large prospective randomized screening trials.MethodsWe assessed the association between randomization to low-dose helical CT scan versus chest x-ray for lung cancer screening and risk of thyroid cancer in the National Lung Screening Trial (NLST). In the Prostate Lung Colorectal and Ovarian Cancer Screening Trial (PLCO), we assessed the association between randomization to regular screening for said cancers versus usual medical care and thyroid cancer risk. Over a median 6 and 11 years of follow-up in NLST and PLCO, respectively, we identified 60 incident and 234 incident thyroid cancer cases. Cox proportional hazards regression was used to calculate the cause specific hazard ratios (HR) and 95% confidence intervals (CI) for thyroid cancer.ResultsIn NLST, randomization to lung CT scan was associated with a non-significant increase in thyroid cancer risk (HR = 1.61; 95% CI: 0.96–2.71). This association was stronger during the first 3 years of follow-up, during which participants were actively screened (HR = 2.19; 95% CI: 1.07–4.47), but not subsequently (HR = 1.08; 95% CI: 0.49–2.37). In PLCO, randomization to cancer screening compared with usual care was associated with a significant decrease in thyroid cancer risk for men (HR = 0.61; 95% CI: 0.49–0.95) but not women (HR = 0.91; 95% CI: 0.66–1.26). Similar results were observed when restricting to papillary thyroid cancer in both NLST and PLCO.ConclusionOur study suggests that certain medical encounters, such as those using low-dose helical CT scan for lung cancer screening, may increase the detection of incidental thyroid cancer.

Obesity and Thyroid Cancer: Is Leptin the (Only) Link?

Obesity and Thyroid Cancer: Is Leptin the (Only) Link?

Abstract 2541: A prospective study of medical diagnostic x-rays and risk of thyroid cancer.

Abstract While diagnostic x-rays provide important medical benefits, cancer risks associated with their exposure are also possible. The thyroid gland is the most radiosensitive organ, and radiotherapy to the head and neck is associated with an increased risk of thyroid cancer. However, it is not known whether diagnostic x-rays, which yield a lower dose of ionizing radiation to the thyroid gland than radiotherapy, also increase the risk. The United States Radiological Technologists study (1983-2006) is a nationwide, prospective cohort with extensive questionnaire data on history of personal diagnostic imaging procedures collected prior to cancer diagnosis. Cox proportional hazards were used to estimate thyroid cancer (TC) risks related to the number and type of selected procedures. Potential modifying effects of age and calendar year of the first x-ray in each category of procedures were assessed. Incident thyroid cancers (n=251) were diagnosed among 75,494 technologists (1.3 million person-years, mean follow-up=17 years). Overall, there was no clear evidence of TC risks associated with diagnostic x-rays, except for dental x-rays. The authors observed a 13% increase in TC risk for every 10 reported dental x-rays (95%CI: 1.01-1.26), driven by dental x-rays first received before 1970, but no evidence that the relationship between dental x-rays and TC was associated with childhood or adolescent exposures as would have been anticipated. The lack of association of TC with x-rays which expose the thyroid to higher radiation doses than dental x-rays underscores the need to conduct a detailed radiation exposure assessment to enable quantitative evaluation of risk. Citation Format: Gila I. Neta, Preetha Rajaraman, Amy Berrington de Gonzalez, Michele Doody, Bruce Alexander, Steve Simon, D. Michal Freedman, Martha Linet, Alice Sigurdson. A prospective study of medical diagnostic x-rays and risk of thyroid cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2541. doi:10.1158/1538-7445.AM2013-2541 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

A Prospective Study of Medical Diagnostic Radiography and Risk of Thyroid Cancer

Although diagnostic x-ray procedures provide important medical benefits, cancer risks associated with their exposure are also possible, but not well characterized. The US Radiologic Technologists Study (1983-2006) is a nationwide, prospective cohort study with extensive questionnaire data on history of personal diagnostic imaging procedures collected prior to cancer diagnosis. We used Cox proportional hazard regressions to estimate thyroid cancer risks related to the number and type of selected procedures. We assessed potential modifying effects of age and calendar year of the first x-ray procedure in each category of procedures. Incident thyroid cancers (n = 251) were diagnosed among 75,494 technologists (1.3 million person-years; mean follow-up = 17 years). Overall, there was no clear evidence of thyroid cancer risk associated with diagnostic x-rays except for dental x-rays. We observed a 13% increase in thyroid cancer risk for every 10 reported dental radiographs (hazard ratio = 1.13, 95% confidence interval: 1.01, 1.26), which was driven by dental x-rays first received before 1970, but we found no evidence that the relationship between dental x-rays and thyroid cancer was associated with childhood or adolescent exposures as would have been anticipated. The lack of association of thyroid cancer with x-ray procedures that expose the thyroid to higher radiation doses than do dental x-rays underscores the need to conduct a detailed radiation exposure assessment to enable quantitative evaluation of risk.

Overweight, Obesity and Thyroid Cancer Risk: A Meta-analysis of Cohort Studies

This meta-analysis examined the relationship between excess body weight or body mass index (BMI) and risk of thyroid cancer. PubMed(®), MEDLINE(®), EMBASE™ and Academic Search™ Premier databases were searched to identify cohort studies examining the effect of being overweight or obese on the risk of thyroid cancer. The inclusion criteria were met by seven cohort studies (total number of thyroid cancer cases, 5154). The pooled relative risk (RR) of thyroid cancer was 1.13 (95% confidence interval [CI] 1.04, 1.22) for overweight. Obesity was also linked with increased thyroid cancer risk in males and females, the strength of the association increasing with increasing BMI. The combined RR of thyroid cancer was 1.18 (95% CI 1.11, 1.25) for excess body weight (overweight and obesity combined). Being overweight was associated with a significant increase in thyroid cancer risk among non-Asians, but not among Asians. Overweight, obesity and excess body weight were all associated with papillary thyroid carcinoma risk. The association between overweight/obesity/excess body weight and thyroid cancer risk was confirmed.

Cancer risk after medical exposure to radioactive iodine in benign thyroid diseases: a meta-analysis

Radioiodine-131 ((131)I) is widely used for diagnosis and treatment of benign thyroid diseases. Observational studies have not been conclusive about the carcinogenic potential of (131)I and we therefore conducted a meta-analysis. We performed a literature search till September 2011 which included (131)I as a diagnostic or treatment modality ((131)I for treatment of thyroid cancer was excluded). Data on 64 different organ or organ group subsets comprising 22 029 exposed subjects in the therapeutic cohorts and 24 799 in the diagnostic cohorts in seven studies were included. Outcome was pooled as the relative risk (RR) using both standard and bias adjusted methods. Quality assessment was performed using a study-specific instrument. No increase in overall (RR 1.06, 95% CI: 0.94-1.19), main organ group or combined organ group (four groups known to concentrate (131)I; RR 1.11, 95% CI: 0.94-1.31) risks was demonstrable. Individual organs demonstrated a higher risk for kidney (RR 1.70, 95% CI: 1.15-2.51) and thyroid (RR 1.99, 95% CI: 1.22-3.26) cancers with a strong trend for stomach cancer (RR 1.11, 95% CI: 0.92-1.33). A thyroid dose effect was seen for diagnostic doses. While there is no increase in the overall burden of cancer, an increase in risk to a few organs is seen which requires substantiation. The possible increase in thyroid cancer risk following diagnostic (131)I use should no longer be of concern given that it has effectively been replaced by the use of 99mTc-pertechnetate.

Diabetes and Thyroid Cancer Risk in the National Institutes of Health-AARP Diet and Health Study

We hypothesized that diabetes may play a role in thyroid cancer risk due to the parallel secular rise in diabetes prevalence and morbidity in the United States, the higher prevalence of thyroid disorders among diabetics compared with the general population, and the potential roles of metabolic syndrome, obesity, and diabetes as precipitating factors in cancer development. We assessed the association between self-reported diabetes and the risk of differentiated thyroid cancer in the NIH-AARP Diet and Health Study, a prospective cohort of 200,556 women and 295,992 men, 50-71 years of age, in 1995-1996. Diabetes status and information on potential confounders was ascertained using a self-administered questionnaire. During an average of 10 years of follow-up, 585 thyroid cancer cases were identified. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for thyroid cancer and thyroid cancer subtypes in men and women according to diabetes status. Nine percent of the total baseline cohort reported a history of diabetes (7% of women, 10% of men). A nonsignificant 25% increase in thyroid cancer risk (HR = 1.25; 95% CI: 0.95-1.64) was associated with diabetes. Among women, the risk was significantly increased (HR = 1.46, 95% CI: 1.01-2.10). The risk was not elevated among men (HR = 1.04, 95% CI: 0.69-1.58). In this cohort, diabetic women with differentiated thyroid cancer were at somewhat higher risk of follicular thyroid cancer (HR = 1.92; 95% CI: 0.86-4.27) than papillary thyroid cancer (HR = 1.25; 95% CI: 0.80-1.97). This study lends support to the hypothesis that diabetes increases the risk of differentiated thyroid cancer.

Neoplasms Following Childhood Radium Irradiation of the Nasopharynx23

Eighteen to 35 years after admission to a clinic for the prevention of deafness, no increased overall cancer risk could be detected among 904 persons who had been treated with nasopharyngeal radium irradiation when compared with the risk among 2,021 persons who were either treated surgically or not treated at all, although there were differences at specific sites. An increased risk of developing both benign and malignant head and neck tumors was found among irradiated persons. Whereas no one head and neck site showed a statistically significant excess, a slight excess of brain cancer occurred 15-20 years after radium treatment. No increase in thyroid cancer risk was observed, a result possibly attributable to the low radiation doses to this organ, and the relatively small population irradiated.