Significance of First Thyroglobulin Level at the Time of Remnant Ablation in Predicting Clinical Course in Patients with Differentiated Thyroid Carcinoma

WOS: 000326456200003Objectives: To review the significance of first thyroglobulin (Tg) values at the time of remnant ablation, in assessing the clinical course in patients with differentiated thyroid cancer (DTC) Design: Retrospective study Setting: Faculty of Medicine, Ege University, Turkey Subjects: A total of 474 patients with DTC excluding those with positive thyroglobulin auto-antibodies and extra-cervical metastases Intervention: Thyroidectomy followed by radioiodine ablation Main outcome measures: Thyroglobulin, remission rate and clinical course Results: The initial Tg levels at the time of ablation were classified as 30 ng/ml (Group 4). The distribution of the patients was; Group 1: 216 (45.5%), Group 2: 126 (26.5%), Group 3: 81 (17.1%), Group 4: 51 (10.7%). Clinical outcome was categorized as: 1) complete remission, 2) Tg (+ve) and whole body iodine scan (-ve) and 3) cervical metastases. The highest remission rate (99.1 - 92.6 %) was achieved in groups 1, 2 and 3. The clinical course was found to be significantly related with the first Tg levels (Chi-Square test, chi(2), df = 6 p = 0.0001). The PPV and NPV of serum Tg > 30 ng/ml and 30 ng/ml