Endocrine Abstracts

JOINT1338

Introduction: Differentiated thyroid carcinoma (DTC), although the most common endocrine malignancy, has a better overall survival rate than most malignancies. It has been presumed that intermediate and high-risk tumors require long term suppression with thyroid hormones in order to prevent thyroid stimulating hormone (TSH) tumor growth. Given the interplay between cardiovascular system, metabolic parameters and thyroid hormones, long term subclinical or overt hyperthyroidism might additionally impact negatively the survival of these patients. Moreover, radioactive iodine therapy (RAI) can also play a role in the development of cardiovascular pathology of these patients. Not enough studies investigate this fine balance and current recommendations are based on moderate quality evidence with heterogenous data.

Objective: We performed a retrospective observational study in order to investigate the relationship between cardiovascular and metabolic profiles of patients with DTC who underwent total thyroidectomies in our hospital from 2010-2024. Mean follow-up time was 5.34 years (SD=4.76).

Results: A total of 144 patients were included, median age at diagnosis 52.5 years (IQ r = 22), 88.19% females. Papillary thyroid cancer accounted for 93.62% of cases and 72.83% were stage I. Fifty-five (38.19%) were under suppressive therapy (defined as TSH<0.5 uUI/ml) and 64.58% underwent RAI treatment with a median of 50 (IQ r = 125) mCi doses. We compared metabolic profiles of TSH-suppressed and non-suppressed groups, which were similar in terms of age, BMI and gender. We found no statistically significant differences between glycemia, HbA1c, lipid profiles, systolic and diastolic blood pressure and heart rate in these two groups. Fibrinogen levels were higher (363.83+/- 71.69 mg/dl vs 319.77 +/- 51.08, one-sided p= 0.029) in patients with suppressed TSH. Same analysis was performed with respect to RAI treatment and higher heart rate was found in patients who received RAI therapy (P = 0.014). Not enough patients developed cardiovascular pathologies after DTC treatment in order to achieve statistical significance.

Conclusion: More studies with longer follow-up periods that also investigate cardiovascular and metabolic outcomes are needed in order to assess and customize life-long management of patients with DTC. The possible low-grade inflammation and elevated heart rate could be indicative of future cardiometabolic negative outcomes in these patients.