Assessment of thyroid nodules by technetium-99m-tetrofosmin scintigraphy

Thyroid nodularity is a common finding. The incidence of thyroid cancer in the general population is estimated at 0.1%. Thyroid nodules are evaluated by palpation, ultrasonography, radionuclide scintigraphy and fine-needle aspiration cytology. Routine thyroid scintigraphy is made by using Tc-99m-pertechnetate or the I-131 and I-123 scintigraphic method. Tc-99m-tetrofosmin accumulates in the myocardium, skeletal muscle, liver, spleen breast tissue, kidney and normal and pathological thyroid tissue. We investigated 36 patients (28 females and 8 males) with solitary and/or multiple thyroid nodules. All the patients were euthyroid, and their thyroid nodules were diagnosed by palpation and ultrasound examination. Thyroid scintigraphy was applied by Tc-99m-pertechnetate, then thyroid fine-needle aspiration biopsy was performed. Finally, Tc-99m-tetrofosmin scintigraphy was carried out. Five patients (14.8%) had differential thyroid carcinoma, 23 (63.8%) had thyroid adenoma, 1 (0.02%) had Riedel's thyroiditis and 7 (19.4%) had follicular cyst. We detected 80% uptake in the early phase and 100% in the late phase by Tc-99m-tetrofosmin scintigraphy in the differentiated thyroid carcinoma group. In summary, we claim that Tc-99m-tetrofosmin may be an important scintigraphic method to identify thyroid malignancy from benign thyroid pathologies.