Abstract
With increasing numbers of childhood cancer survivors who were treated with radiation, there is a need to evaluate potential biomarkers that could signal an increased risk of developing thyroid cancer. We aimed to examine the relationships between thyrotropin and thyroglobulin levels and the risk of developing thyroid nodules and cancer in a cohort of radiation-exposed children. 764 subjects who were irradiated in the neck area as children were examined and followed for up to 25 years. All subjects underwent a clinical examination, measurements of thyrotropin, thyroglobulin levels and thyroid imaging. At baseline, 216 subjects had thyroid nodules and 548 did not. Of those with nodules, 176 underwent surgery with 55 confirmed thyroid cancers. During the follow-up, 147 subjects developed thyroid nodules including 22 with thyroid cancer. Thyroglobulin levels were higher in subjects with prevalent thyroid nodules (26.1 ng/mL vs 9.37 ng/mL; P < 0.001) and in those who had an initial normal examination but later developed thyroid nodules (11.2 ng/mL vs 8.87 ng/mL; P = 0.017). There was no relationship between baseline thyrotropin levels and the prevalent presence or absence of thyroid nodules, whether a prevalent neoplasm was benign or malignant, subsequent development of thyroid nodules during follow-up or whether an incident nodule was benign or malignant. In conclusion, in radiation-exposed children, higher thyroglobulin levels indicated an increased risk of developing thyroid nodules but did not differentiate between benign and malignant neoplasms. There was no association between the baseline TSH level and the risk of developing thyroid nodules or cancer.
Highlights
Radiation-induced thyroid cancer remains an important clinical concern
In the EPIC cohort, Rinaldi and coworkers demonstrated a significant positive association between the Tg levels and thyroid cancer risk (OR = 9.15) and that higher Tg levels may precede the detection of thyroid cancer by up to 8 years (Rinaldi et al 2014)
We previously reported that thyroglobulin levels increased over time in subjects who developed thyroid nodules (Schneider et al 1985)
Summary
Radiation-induced thyroid cancer remains an important clinical concern. the medical use of radiation for treating benign head and neck conditions has been abandoned, the risks associated with the use of such treatments in the middle of last century persists for decades after the exposure; currently, radiation is frequently used to treat children with cancer and, as of 2013, over 400,000 survivors are alive in the United States; and nuclear accidents, such as those at Chernobyl and Fukushima, remain possible (Sinnott et al 2010, Wheatley et al 2017). While several studies have attempted to identify biomarkers that are predictive of the likelihood of malignancy in patients with thyroid nodules in the general population, the data correlating these factors in radiation-induced thyroid cancer remain scarce. Several publications have shown that the risk of malignancy in sporadic thyroid nodules increases with serum thyrotropin (TSH) concentrations, even within the normal range (Boelaert et al 2006, Haymart et al 2008, Witczak et al 2016). In a case–control analysis matching thyroid cancer cases with controls nested in the European Prospective Investigation into Cancer and Nutrition cohort (EPIC) study, Rinaldi and coworkers found that thyroid cancer risk was negatively associated with the TSH levels (Rinaldi et al 2014). The EPIC study found that high thyroglobulin (Tg) levels preceded the diagnosis of thyroid cancer by almost a decade. The predictive value of these biomarkers in radiation-exposed individuals has not yet been determined
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
