Long-term Effect of Postoperative Radioactive Iodine Therapy on Parathyroid Function in Patients with Differentiated Thyroid Cancer

The study aimed to assess the impact of postoperative radioactive iodine (RAI) therapy on parathyroid function in patients who underwent total or subtotal thyroidectomy for differentiated thyroid cancer (DTC). Data from 150 patients treated with RAI for DTC and 76 patients with low-risk DTC not receiving RAI were retrospectively analyzed. Clinical characteristics, preoperative and 1-month postoperative biochemical parameters, and adjusted calcium, phosphorus, parathyroid hormone (PTH), and 25-hydroxyvitamin D3 (25-OH-D) levels at 3 months, 1 year, 3 years, and 5 years post-RAI (or in the low-risk group) were recorded. A total of 226 DTC patients were included in the study (80.5