title: Dynamic Risk Stratification for Predicting Recurrence in Patients with Differentiated Thyroid Cancer Treated Without Radioactive Iodine Remnant Ablation Therapy.
abstract: 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 of this study was to validate a new dynamic risk stratification (DRS) system for the prediction of structural recurrent/persistent disease in patients with DTC treated without radioactive iodine (RAI) remnant ablation therapy.
  
  
  
  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.
  
  
  
  During a median follow-up of 8.6 years, 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 DFS among the DRS groups (p < 0.001). The hazard ratio (HR) of recurrent/persistent disease was significantly higher in the 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 staging system and the American Thyroid Association initial risk classification did not effectively predict recurrence of DTC.
  
  
  
  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.
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Suyeon
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Won Gu
authors.initials: WG
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Eyun
authors.initials: E
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Hye-Seon
authors.initials: HS
authors.lastname: Oh
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Mijin
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Hyemi
authors.initials: H
authors.lastname: Kwon
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Min Ji
authors.initials: MJ
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Tae Yong
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Young Kee
authors.initials: YK
authors.lastname: Shong
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
authors.forename: Won Bae
authors.initials: WB
authors.lastname: Kim
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000473:pathology / Q000601:surgery*; D000328:Adult; D002291:Carcinoma, Papillary / Q000473:pathology / Q000601:surgery*; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D037981:Neck Dissection; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D018570:Risk Assessment; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000473:pathology / Q000601:surgery*; D013965:Thyroidectomy
keywords: differentiated thyroid cancer; disease-free survival; dynamic risk stratification; low risk; recurrence