Outcomes Without Adjuvant Radioactive Iodine Among Pediatric Patients With Papillary Thyroid Cancer

According to an retrospective cohort study, selected pediatric patients may not require adjuvant radioactive-iodine therapy, avoiding unnecessary risks of radioactive iodine while still achieving excellent long-term outcomes.

In an interview with Oncology Learning Network, lead study author, Luz Castellanos, MD, MD Anderson Cancer Center, Houston, Texas, describe the potential risks of radioactive iodine therapy, saying, “We now recognize potential risks, particularly in younger patients, including sialadenitis, ocular dryness, bone marrow, suppression, xerostomia, dental caries, gonadal damage. And there’s concern for potential long-term effects with repeated dosing especially.” Dr Castellanos went on, “Experts are becoming increasingly more aware that not all patients benefit from radioactive iodine treatments, and there’s multiple limitations to its effectiveness.”

This study included 93 patients who were diagnosed with stage 1 papillary thyroid cancer, between January 1, 1990, to December 31, 2021, who were intentionally not treated with radioactive iodine within 1 year of diagnosis. Of the 93 patients, 49% had cervical lymph node metastases. Initial management of these patients included thyroidectomy with or without neck dissection (75%), lobectomy with or without neck dissection (21%), or a Sistrunk procedure for ectopic papillary thyroid cancer (4%). There were 2/3 of patients considered low-risk and 1/3 considered intermediate or high risk. Clinical characteristics, management, and disease outcomes were assessed. The co-primary outcomes were disease status at last follow-up and proportion of patients remaining cancer-free.

With a median of 5.5 years of follow, 91% of patients remained disease-free with no further therapy. There were 9% of patients who had persistent or recurrent disease. There were 4 patients who did eventually receive radioactive iodine therapy, with 1 of which showing clear benefit from this therapy. Further, 2 patients had additional surgery performed, with both showing an excellent response at their last follow-up, with no additional therapy.

Dr Castellanos concluded, “This study does really reinforce the idea that we don’t need a one-size-fits-all approach to pediatric thyroid cancer. This aligns with the shift in how we’ve been treating these patients. … We’re showing that some children, and this is particularly in stage 1, who have low risk and no evidence of disease, despite having noval involvement, can have excellent outcomes without radioactive iodine.”

Source:

Castellanos LE, Zafereo ME, Sturgis EM, et al. Pediatric papillary thyroid carcinoma: Outcomes after surgery without adjuvant radioactive iodine. JCEM. 2025;110(2):e208-e217. doi:10.1210/clinem/dgae576