title: Impact of early vs late postoperative radioiodine remnant ablation on final outcome in patients with low-risk well-differentiated thyroid cancer.
abstract: OBJECTIVE
  Postoperative radioiodine remnant ablation (RRA) represents an adjunctive therapeutic modality in patients with differentiated thyroid cancer (DTC). The impact of late vs early RRA on the outcome of DTC is currently unclear. The aim of the study was to evaluate the outcome of patients with DTC according to RRA timing.
  A total of 107 TNM stage 1 DTC patients were divided into two groups. In group A (n = 50), RRA was administered in less than 4·7 months median 3·0 (range 0·8-4·7), while in group B (n = 57) in more than 4·7 months median 6 (4·8-30·3) after thyroidectomy. Remission was achieved when stimulated serum Tg levels were undetectable, in the absence of local recurrence or cervical lymph node metastases on the neck ultrasound.
  
  
  RESULTS
  All patients underwent near-total thyroidectomy. The mean age at diagnosis was 49·3 years (range: 18-79 years). There were no statistically significant differences in the histological subtype, the TNM stage, the dose of radioiodine and the time of follow-up, between the two groups. After the RRA treatment, 44 group A patients (88%) were in remission and 6 (12%) in persistence; while in group B, 52 (91·2%) were in remission, 1 (1·8%) in persistence and 4 (7%) in recurrence. At their latest follow-up median 87·3 (23·3-251·6 months), all patients were in remission, either as a result of further iodine radioiodine therapy (in 11 patients) or watchful monitoring.
  
  
  CONCLUSIONS
  The timing of RRA seems to have no effect on the long-term outcome of the disease. Therefore, urgency for radioiodine ablation in patients with low-risk thyroid cancer is not recommended.
authors.affiliation: Department of Endocrinology, Diabetes and Metabolism, Evangelismos Hospital, Athens, Greece.
authors.forename: Sofia
authors.initials: S
authors.lastname: Tsirona
authors.forename: Varvara
authors.initials: V
authors.lastname: Vlassopoulou
authors.forename: Marinella
authors.initials: M
authors.lastname: Tzanela
authors.forename: Phoebe
authors.initials: P
authors.lastname: Rondogianni
authors.forename: George
authors.initials: G
authors.lastname: Ioannidis
authors.forename: Charalambos
authors.initials: C
authors.lastname: Vassilopoulos
authors.forename: Efthimia
authors.initials: E
authors.lastname: Botoula
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Trivizas
authors.forename: Ioannis
authors.initials: I
authors.lastname: Datseris
authors.forename: Stylianos
authors.initials: S
authors.lastname: Tsagarakis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018265:Carcinoma, Papillary, Follicular / Q000453:epidemiology / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D011184:Postoperative Period; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D013965:Thyroidectomy; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes