Postsurgery serum thyroglobulin disappearance kinetic in patients with differentiated thyroid carcinoma.

BACKGROUND Knowing the postsurgery thyroglobulin (Tg) kinetic would enable its rationale for use in patients with differentiated thyroid cancer (DTC). Heterogeneous results were previously reported, then we aimed to evaluate the postsurgery Tg kinetic in a large group of patients with DTC. METHODS Enrolled were 96 patients with DTC. Serum Tg was measured first at 5 minutes, then at 24, 48, 72, 96, and 120 hours after thyroidectomy. The Tg half-life (Tg[t(1/2)]) was estimated in a 1-compartment model. A simplified 2-point formula (24 and 120 hours) was also used. RESULTS The mean Tg(t(1/2)) was 28.53 to 30.22 hours in 1-compartment model and 27.39 hours when estimated by a simplified formula. A strong inter-methods relationship was found (p < .001). CONCLUSIONS A reliable Tg(t(1/2)) estimation could be obtained by a simplified formula requiring only 2 postsurgery Tg measurements (24 and 120 hours, respectively).