APPLICATION OF POST-SURGICAL STIMULATED THYROGLOBULIN FOR RADIOIODINE REMNANT ABLATION SELECTION IN LOW-RISK PAPILLARY THYROID CARCINOMA

Background. We present our ongoing experience in the use of postsurgical stimulated serum thyroglobulin (Stim-Tg) to assist in radioiodine remnant ablation (RRA) decision-making. Methods. Patients with low-risk well-differentiated thyroid carcinoma (WDTC) with undetectable anti-Tg antibodies were prospectively followed after total thyroidectomy and therapeutic central compartment neck dissection, when indicated. Stim-Tg was performed 3 months postoperatively and used to base RRA selection. Results. Of 104 patients, 59 patients (56.7%) had an undetectable Stim-Tg after thyroidectomy, 35 (33.7%) had Stim-Tg values of 1-5 mu g/L, and 10 (9.6%) had Stim-Tg values >5 mu g/L. RRA was administered to 1 patient (1.7%) with undetectable Stim-Tg, 6 patients (17.1%) with Stim-Tg1-5 mu g/L, and 9 patients (90%) with Stim-Tg >5 mu g/L, for a total of 16 patients (15.4%) receiving RRA. When compared to current RRA selection guidelines, the proposed protocol achieved a significantly lower RRA administration rate. Conclusion. Stim-Tg measurement performed several months after total thyroidectomy is a useful objective parameter in assisting RRA decision-making for patients with low-risk WDTC. (C) 2010 Wiley Periodicals, Inc. Head Neck 32: 689-698, 2010