Thyroglobulin levels and thyroglobulin doubling time independently predict a positive 18F-FDG PET/CT scan in patients with biochemical recurrence of differentiated thyroid carcinoma.
Eur J Nucl Med Mol Imaging
; 40(6): 874-80, 2013 Jun.
Article
em En
| MEDLINE
| ID: mdl-23463330
ABSTRACT
PURPOSE:
To assess the relationship between serum thyroglobulin (Tg) levels, Tg doubling time (Tg-DT) and the diagnostic performance of (18)F-FDG PET/CT in detecting recurrences of (131)I-negative differentiated thyroid carcinoma (DTC).METHODS:
Included in the present study were 102 patients with DTC. All patients were treated by thyroid ablation (e.g. thyroidectomy and (131)I), and underwent (18)F-FDG PET/CT due to detectable Tg levels and negative conventional imaging. Consecutive serum Tg measurements performed before the (18)F-FDG PET/CT examination were used for Tg-DT calculation. The (18)F-FDG PET/CT results were assessed as true or false after histological and/or clinical follow-up.RESULTS:
Serum Tg levels were higher in patients with a positive (18)F-FDG PET/CT scan (median 6.7 ng/mL, range 0.7-73.6 ng/mL) than in patients with a negative scan (median 1.8 ng/mL, range 0.5-4.9 ng/mL; P < 0.001). In 43 (88 %) of 49 patients with a true-positive (18)F-FDG PET/CT scan, the Tg levels were >5.5 ng/mL, and in 31 (74 %) of 42 patients with a true-negative (18)F-FDG PET/CT scan, the Tg levels were ≤5.5 ng/mL. A Tg-DT of <1 year was found in 46 of 49 patients (94 %) with a true-positive (18)F-FDG PET/CT scan, and 40 of 42 patients (95 %) with a true-negative scan had a stable or increased Tg-DT. Moreover, combining Tg levels and Tg-DT as selection criteria correctly distinguished between patients with a positive and a negative scan (P<0.0001).CONCLUSION:
The accuracy of (18)F-FDG PET/CT significantly improves when the serum Tg level is above 5.5 ng/mL during levothyroxine treatment or when the Tg-DT is less than 1 year, independent of the absolute value.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tireoglobulina
/
Neoplasias da Glândula Tireoide
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Fluordesoxiglucose F18
/
Imagem Multimodal
Tipo de estudo:
Diagnostic_studies
/
Observational_studies
/
Prognostic_studies
Limite:
Adolescent
/
Adult
/
Aged
/
Female
/
Humans
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Male
/
Middle aged
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article