Hürthle cell tumor dwelling in hot thyroid nodules: preoperative detection with technetium-99m-MIBI dual-phase scintigraphy.
Single injection dual-phase scintigraphy (early and late acquisitions) with 99mTc-MIBI was used to differentiate benign and malignant hot thyroid nodules.


METHODS
Thirteen euthyroid and two hyperthyroid patients displaying a hot thyroid nodule on the 99mTc scan due to an autonomously functioning thyroid nodule (AFTN) underwent early (15-30 min) and late (3-4 hr) thyroid scintigraphy after the administration of 740-1000 MBq 99mTc-MIBI. Visual scoring was done to assess nodular tracer uptake and retention. In addition, the nodular-to-thyroid (N/T) uptake ratio in the early and late image and the washout rates (WO) from the nodule and thyroidal tissue were measured. All patients underwent thyroid surgery.


RESULTS
Histopathology revealed a Hürthle cell tumor in three nodules, a benign adenoma with oxyphilic metaplasia in two nodules and a benign adenoma without oxyphilic cells in the remaining 10 nodules. The Hürthle cell tumor nodules displayed intense and persistent uptake of 99mTc-MIBI (N/T was 2.81 +/- 0.52 and 5.53 +/- 1.06 in early and late images, respectively; WO from the nodule was 12.33 +/- 0.47, WO from the thyroidal tissue was 22.00 +/- 3.56). The benign nodules showed intense uptake in the early image and intense uptake to absent retention in the late image (N/T was 2.94 +/- 1.31 and 1.62 +/- 0.50 in the early and late images, respectively; WO from the nodule was 20.25 +/- 2.92, WO from the thyroidal tissue was 20.33 +/- 2.92).


CONCLUSIONS
Single injection dual-phase 99mTc-MIBI scintigraphy of the thyroid with AFTN can identify nodules as a result of the activity of a Hürthle cell tumor, since these tumors cause intense and persistent tracer uptake in contrast with a benign AFTN.
Vattimo
A
A
Nuclear Medicine Unit, Institute of Pathology, University of Siena, Italy.
Bertelli
P
P
Cintorino
M
M
Burroni
L
L
Volterrani
D
D
Vella
A
A
Lazzi
S
S
D018249:Adenoma, Oxyphilic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D013961:Thyroid Gland / Q000473:pathology; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi