ECE2017 Eposter Presentations: Thyroid Thyroid (non-cancer) (260 abstracts)
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Background: Increased incidence of small differentiated thyroid cancer (DTC) has emphasized the need for risk stratification and individualized disease management for these low risk DTCs. The aim was to validate a new dynamic risk stratification (DRS) system for prediction of structural recurrent/persistent disease in patients with DTC treated without radioactive iodine (RAI) remnant ablation therapy.
Methods: This historical cohort study included 357 patients with DTC treated with lobectomy or total thyroidectomy without RAI therapy. We stratified patient response to initial treatment as excellent, indeterminate, biochemical incomplete, and structural incomplete according to the DRS system.
Results: During a median 8.6 year of follow-up, 3.6% patients had structural recurrent DTC. The response was excellent in 71.7% patients, indeterminate in 18.5%, biochemical incomplete in 8.4%, and structural incomplete in 1.4%. There were significant differences in disease-free survival among the DRS groups (P<0.001). The hazard ratio (HR) of recurrent/persistent disease was significantly higher in biochemical incomplete group (HR =20.8, P<0.001) and structural incomplete group (HR =243.3, P<0.001) compared with the excellent group. However, the tumor node metastasis (TNM) staging system and the American Thyroid Association (ATA) initial risk classification did not effectively predict recurrence of DTC.
Conclusions: The new DRS system was effective for predicting risk of recurrent/persistent disease in patients with DTC who underwent lobectomy or total thyroidectomy without RAI remnant ablation.