title: Prognostic value of thyroglobulin serum levels and 131I whole-body scan after initial treatment of low-risk differentiated thyroid cancer.
abstract: Diagnostic iodine-131 whole-body scan ((131)I-WBS) and serum thyroglobulin values (Tg) performed 6 to 12 months after thyroid ablation for differentiated thyroid carcinoma were evaluated in 194 consecutive patients at the Hospital de Navarra, (Pamplona, Spain). All patients underwent near-total thyroidectomy and (131)I ablation with 3.7 GBq. Patients with positive anti-Tg antibodies or with (131)I uptake outside the neck were previously excluded. Uptake of (131)I in the thyroid bed was detected in 27 patients (13.9%). Serum Tg levels were below 0.5 ng/mL in 133 patients, ranged from 0.5-10 ng/mL in 39 patients, and was above 10 ng/mL in 22 patients. After a follow-up of 7.7 +/- 3.3 years, persistence of the illness has been observed in 2 patients with undetectable Tg (1.5%), but metastases were not detected in any case. In those with Tg higher than 0.5 ng/mL, 29 of 61 patients had persistence of the disease (47.5%) with evidence of metastases in 15 (24.5%), irrespective of the initial total body scan (131)I uptake. In conclusion, serum Tg levels obtained after thyroid ablation has a good prognostic value and permits the selection of patients for further diagnostic studies, while diagnostic (131)I-WBS performed at that time did not correlate with results of Tg and scarcely provides additional information.
authors.affiliation: Servicio de Medicina Nuclear, Hospital de Navarra, Pamplona, Spain. emenendt@cfnavarra.es
authors.forename: Edelmiro
authors.initials: E
authors.lastname: Menéndez Torre
authors.forename: María Teresa
authors.initials: MT
authors.lastname: López Carballo
authors.forename: Rosa María
authors.initials: RM
authors.lastname: Rodríguez Erdozáin
authors.forename: Lluís
authors.initials: L
authors.lastname: Forga Llenas
authors.forename: María José
authors.initials: MJ
authors.lastname: Goñi Iriarte
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Barbería Layana
mesh_terms: D015415:Biomarkers / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D013997:Time Factors
chemical_list: D015415:Biomarkers; D007457:Iodine Radioisotopes; D013954:Thyroglobulin