The risk of cardiovascular and all-cause mortality is increased in patients with DTC, independent of age, sex, and cardiovascular risk factors. A lower TSH level is associated with increased cardiovascular mortality, supporting the current European Thyroid Association and the American Thyroid Association guidelines of tempering TSH suppression in patients with low risk of cancer recurrence. Furthermore, patients with DTC may benefit from assessment and treatment of cardiovascular risk factors.

Survival of pediatric DTC is excellent. Therefore, minimizing treatment-related morbidity takes major priority. Our study shows a frequent occurrence of life-long postoperative complications. Adverse effects may be reduced by the centralization of care, which is crucial for children with DTC.

Overall, long-term QoL in survivors of pediatric DTC was normal. Survivors experienced mild impairment of QoL in some domains (physical problems, mental fatigue, and various thyroid cancer-specific complaints). Factors possibly affecting QoL need further exploration.

Pediatric differentiated thyroid cancer (DTC) is a rare disease. Initial treatment of DTC consists of a total or near-total thyroidectomy and 131 I therapy. Previous studies on adults showed that 131 I treatment may reduce salivary gland function (SGF). Studies regarding SGF in children treated for DTC are sparse. Our aim was to assess the long-term effects of 131 I treatment on SGF in survivors of pediatric DTC. Methods: In a nationwide cross-sectional study, SGF in patients treated for pediatric DTC between 1970 and 2013 (.5 y after diagnosis, $18 y old at the time of evaluation) was studied. SGF was assessed by sialometry, sialochemistry, and a xerostomia inventory. Salivary gland dysfunction (SGD) was defined as an unstimulated whole saliva flow of no more than 0.2 mL/min or a stimulated whole saliva flow of no more than 0.7 mL/min. Results: Sixty-five patients underwent 131 I treatment (median age at evaluation, 33 y, with an interquartile range [IQR] of 25-40 y; 86.2% female; median follow-up period, 11 y, with an IQR of 6-22 y). Median cumulative 131 I activity was 5.88 GBq, with an IQR of 2.92-12.95 GBq, and 47.7% underwent multiple 131 I administrations. SGD was present in 30 (47.6%) patients. Levels of amylase and total protein in saliva were reduced. Moderate to severe xerostomia was present in 22 (35.5%) patients. Stimulated salivary secretion was lower and the severity of xerostomia complaints higher in patients treated with higher cumulative 131 I activity. Conclusion: In survivors of pediatric DTC, clinically significant SGD was found in 35.5% and was related to the cumulative 131 I activity of the treatment.