Therapeutic impact of 18FDG-PET/CT in the management of iodine-negative recurrence of differentiated thyroid carcinoma.
BACKGROUND
18-F-fluoro-2-deoxyglucose positron emission tomography ((18)FDG-PET) is useful in the detection of iodine-negative differentiated thyroid carcinoma (DTC). The aim of this prospective study was to assess therapeutic impact of (18)FDG-PET imaging using a PET/computed tomography (CT) system in patients with iodine-negative recurrence of DTC.


METHODS
From 2002 to 2006, patients with recurrence of DTC diagnosed by elevated thyroglobulin level and negative 131-I whole-body scan were included.


RESULTS
Forty-five patients (31 women, 14 men), with a mean age of 55 years, with 36 papillary, 5 follicular, and 4 Hürthle carcinomas, were studied. All patients had previously undergone total thyroidectomy and postoperative thyroid remnant ablation with 131-I. The findings of (18)FDG-PET/CT were positive in 31 patients (68.8%) and negative in 14 (32.2%). Results were true positive in 24 of 31 patients. The sensitivity, positive predictive value, and accuracy of (18)FDG-PET/CT were 63%, 77%, and 53%, respectively. Twenty patients were operated on, 19 had neck surgery with mediastinal lymph node dissection (1 case) and lung resection (1 case), and 1 underwent lung resection. Seven patients had a stimulated thyroglobulin level <1 ng/mL.


CONCLUSIONS
(18)FDG-PET/CT is able to select patients who can benefit from surgery. Normalization of thyroglobulin is observed in one third of operated patients.
Clinique de Chirurgie Digestive et Endocrinienne, IMAD, Nantes, France. eric.mirallie@chu-nantes.fr
Eric
E
Mirallié
Thomas
T
Guillan
Boumédiene
B
Bridji
Isabelle
I
Resche
Caroline
C
Rousseau
Catherine
C
Ansquer
Caroline
C
Bodet-Milin
Chantal
C
Curtet
Bruno
B
Carnaille
Arnaud
A
Murat
Bernard
B
Charbonnel
Françoise
F
Kraeber-Bodéré
D018263:Adenocarcinoma, Follicular / Q000000981:diagnostic imaging* / Q000601:surgery; D018249:Adenoma, Oxyphilic / Q000000981:diagnostic imaging / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002454:Cell Differentiation; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging; D018579:Patient Selection; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D013954:Thyroglobulin / Q000097:blood; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D013965:Thyroidectomy; D014057:Tomography, X-Ray Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D013954:Thyroglobulin