Radioactive Iodine Ablation in the Prevention of Papillary Thyroid Microcarcinoma Recurrence

How effective is radioactive iodine (RAI) ablation in halting the recurrence of papillary thyroid microcarcinoma (PTMC) in patients in remission from the condition?

Though the long-term prognosis of PTMC  following initial treatment is favorable in many patients, researchers in Korea argue that disease recurrence is a problem that is need of further exploration. In their study, “Radioactive iodine ablation does not prevent recurrences in patients with papillary thyroid microcarcinoma,” the researchers sought to evaluate the effectiveness of 1 technique in stopping disease recurrence in PTMC patients. The study appeared online ahead of print in September 2012 in Clinical Endocrinology.

The researchers looked at 2,579 patients who had surgery for thyroid cancer at the Samsung Medical Center at the Sungkyunkwan University School of Medicine in Korea. The surgeries took place between 1994 and 2004. Of the initial population, 704 patients who were thought to be disease-free were followed up with after their initial treatment (median time of follow-up was 64 months).

Additionally, some of the patients were separated into subgroups (patients with cervical lymph node metastases, multifocality, or microscopic extrathyroidal extension); individuals in these groups were labeled as having an intermediate risk for disease recurrence.

The study results showed that the disease recurred in 6 patients within 10 to 70 months following their initial treatment. All 6 of the patients had received RAI treatment following a total thyroidectomy. The findings showed that the likelihood of recurrence did not differ between participants who had undergone RAI ablation and those that did not. This finding held for the patients in the intermediate-risk for recurrence group.

The researchers conclude that their study demonstrates that undergoing RAI ablation following a total thyroidectomy does not prevent the recurrence of tumors in low- and intermediate-risk patients recovering from PTMC. However, they state that more research is needed to confirm their findings—particularly, research that involves a larger sample size, and a longer mean follow-up time.