Long-Term Surveillance of Papillary Thyroid Cancer Patients Who Do Not Undergo Postoperative Radioiodine Remnant Ablation: Is There a Role for Serum Thyroglobulin Measurement?

Context: Serum thyroglobulin (Tg) assays are considered fundamental in postoperative surveillance of differentiated thyroid cancer (DTC) patients. However, the postsurgical profile of Tg levels has never been specifically investigated in patients who do not undergo radioiodine remnant ablation (RRA). Objectives: Our objective was to explore the evolution of Tg levels over time in DTC patients treated with total or near-total thyroidectomy without RRA. Design: We retrospectively analyzed 290 consecutively diagnosed cases of low-risk (American Thyroid Association criteria) DTC treated with thyroidectomy alone and followed yearly with neck ultrasonography and serum Tg assays. We compared final Tg values in this group and a matched group of 495 RRA-positive patients. Temporal trends of serial Tg levels were also analyzed in 78 of the RRA-negative patients monitored with a high-sensitivity immunoradiometric assay. Results: After follow-up of 2.5–22 yr (median 5 yr), final Tg levels were undetectable (