Introduction: Low-risk papillary thyroid microcarcinomas (PTMC) have an indolent course and favorable prognosis. In the Philippines, radioactive iodine (RAI) remnant ablation is frequently given to patients with low-risk PTMC because of studies showing that Filipinos have more aggressive thyroid cancers. This study aims to determine if RAI remnant ablation prevents thyroid cancer recurrence among Filipino patients with low-risk PTMC who underwent thyroidectomy at a tertiary hospital in the Philippines. Methods: A retrospective cohort study was conducted among adult patients with low-risk PTMC who underwent total thyroidectomy from 2006 to 2016. Outcomes were classified as positive or negative for disease recurrence based on imaging results and serum thyroglobulin levels during each follow-up visit. Recurrence-free curves were estimated using Kaplan-Meier method and compared using Cox regression analysis. Results: A total of 90 cases of low-risk PTMC were included in the analysis with a mean follow-up duration of 41.88 months (range, 12-129 months). Forty eight patients (53.33%) underwent RAI remnant ablation (RAI group) and 42 patients (46.67%) did not (No RAI group). Six patients (6.67%) had disease recurrence at a median of 18 months (range, 12-70 months). The recurrence rates in the No RAI group were 2.8% at one year and 10.84% in five years and the recurrence rates in the RAI group were 0% at one year and 9.84% at five years. (HR, 5.34; 95% CI, 0.86 to 33.02; P=0.07). Conclusion This study did not provide sufficient evidence that RAI remnant ablation prevents disease recurrence in Filipino patients with low-risk PTMC. Future randomized, prospective trials involving larger sample sizes and longer follow-up duration are necessary to confirm our findings.
Thyroid Neoplasms