The application of SPECT/CT scintigraphy with MIBI-Tc⁹⁹(m) in the diagnosis of thyroid nodules - a preliminary report.
BACKGROUND
Thyroid cancer diagnosis is based mainly on fine needle aspiration biopsy (FNAB) performed under ultrasonography guidance. Questions arise in cases of an inconclusive FNAB result - when there is no clear evidential data to support the existence of a malignant lesion or when there are any other reasons which make the decision process difficult, such as the patient's age or coexisting diseases. To clarify this issue the patient should be encouraged to undergo surgery treatment or to be followed up. Thyroid scintigraphy with an oncophilic tracer such as MIBI-Tc⁹⁹(m) may be helpful.


METHODS
The study comprised a group of 12 patients, aged 54-75 (av. 63.5) years, who, in 2009, underwent planar and SPECT/CT thyroid scintigraphy with MIBI-Tc⁹⁹(m) using washout method. The tumour/background ratio in early and delayed images was calculated and the wash-out ratio was estimated. Patients with increased focal lesion uptake were operated on and the lesions were histopathologically verified.


RESULTS
Abnormal scintigraphy results were obtained in 8 patients (10 lesions) and normal results in 4 patients (5 lesions). Out of 15 studies, in 13 cases the washout from the lesion was observed within 2 hours. It was noticed that the images obtained with SPECT/CT washout method were clearer and easier to read in comparison to planar studies. Three patients with an abnormal results underwent surgery and had benign histopathology results after the operation, in 3 patients the observation is being confirmed without any increase in malignancy suspicions, and 2 were lost for observation.


CONCLUSIONS
Our preliminary results do support the use of MIBI-Tc⁹⁹m in the evaluation of indeterminate thyroid nodules. To validate the hypothesis that MIBI-Tc⁹⁹(m) may be used to exclude malignancy in lesions indeterminate by FNAB we propose to use SPECT-CT derived images and standardized evaluation criteria.
Department of Nuclear Medicine, Pomeranian Medicine University, Szczecin, Poland. marlist@fiber.net.pl
Maria H
MH
Listewnik
Bożena
B
Birkenfeld
Hanna
H
Piwowarska-Bilska
Katarzyna
K
Cichoń-Bańkowska
Lidia
L
Iglińska-Wagner
Wanda
W
Watrak
Wiesława
W
Smolira
Piotr
P
Zorga
Krystyna
K
Niedziałkowska
Bogumiła
B
Elbl
Marek
M
Sawrymowicz
D000368:Aged; D044963:Biopsy, Fine-Needle; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017256:Technetium Tc 99m Sestamibi; D013959:Thyroid Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D014055:Tomography, Emission-Computed / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D017256:Technetium Tc 99m Sestamibi