Clinical utility of technetium-99m methoxisobutylisonitrile imaging in differentiated thyroid carcinoma: comparison with thallium-201 and iodine-131 Na scintigraphy, and serum thyroglobulin quantitation

Abstract

Recently, technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) has been used to image thyroid carcinoma. A prospective study was performed to compare the efficacy of 99mTc-MIBI to thallium-201 (201Tl) scintigraphy in patients with differentiated thyroid carcinoma. The clinical utility of all radionuclide imaging modalities, i.e., 99mTc-MIBI, 201Tl, and iodine-131 Na (131I-Na), as well as serum thyroglobulin estimation, was evaluated. Thirty-four post-thyroidectomy patients (age range: 26-76 years) underwent 45 studies. Histopathologies studied included fourteen papillary, eight papillary-follicular, ten follicular, one Hürthle cell, and one medullary carcinoma of the thyroid. Following optimal stimulation of endogenous thyroid stimulating hormone (i.e, TSH 50 mU/ml), the patients underwent 201Tl and 99mTc-MIBI scintigraphy. Concomitant 131I-Na scintigraphy was performed and serum thyroglobulin levels were measured. Sixteen scan sets were performed prior to 131I-Na ablation therapy. Twenty-nine scan sets were performed following 131I-Na ablation therapy. The presence or absence of thyroid cancer was established by clinical, biochemical, radiologic, and/or biopsy findings. There was no significant difference in sensitivity and specificity of 201Tl scintigraphy versus 99mTc-MIBI scintigraphy in pre- and postablation studies. 131I-Na scintigraphy with determination of thyroglobulin level was sufficient in preablation studies. Among postablation patients, the addition of 99mTc-MIBI or 201Tl offered a higher diagnostic yield. Between the 201Tl and 99mTc-MIBI studies, there was a concordance of 69% in preablation and 97% among postablation patients (P=0.027). It is concluded that 99mTc-MIBI is a suitable alternative to 201Tl scintigraphy in thyroid carcinoma, especially following thyroidectomy and 131I-Na therapy. 131I-Na scintigraphy with serum thyroglobulin is adequate in both pre- and postablation patients. Among the post-131I-Na ablation patients, 99mTc-MIBI or 201Tl is extremely valuable for tumor localization, especially when the 131I-Na whole-body scan is negative. The combination of 99mTc-MIBI or 201Tl scintigraphy with 131I-Na and serum thyroglobulin offers the highest diagnostic yield.

Radionuclide-Labeled Somatostatin Analogues for Diagnostic and Therapeutic Purposes in Nonmedullary Thyroid Cancer

“…In various studies the sensitivity of both modalities was found to be comparable (22)(23)(24)(25)(26)(27), confirming our results (28). Nevertheless, the average reported sensitivity of 60% is not satisfactory.…”

“…Except for eight patients (number 14a, euthyroid prior to surgery; numbers 6,22,35,37, 48 under nonsuppressive levothyroxine dosage; number 13, 27 under hypothyroid conditions/levothyroxine withdrawal shortly before to the radioiodine scan), all 111 In-Pentetreotide scans were performed under TSH-suppressive levothyroxine therapy (for corresponding TSH levels see Table 1). The findings were compared intraindividually with conventional imaging modalities, including ultrasound of the neck (all patients), x-ray (n 5 7), computed tomography (CT) (n 5 38), magnetic resonance imaging (MRI) (n 5 10), 99m Tc-DPD bone scintigraphy (n 5 10), and in one case, angiography, with other radiotracers for whole-body tumor scintigraphy ( 131 iodine, 99m Tc-sestamibi scintigraphy, and 201 Tl-chloride) and with 2-[ 18 F]fluoro-2-deoxy-D-glucose position emission tomography (FDG-PET) (n 5 23).…”

Diagnostic management of suspected metastatic thyroid carcinoma: clinical value of octreotide scintigraphy in patients with negative high-dose radioiodine scans

“…Several radiopharmaceuticals, such as thallium-201 chloride and technetium-99m-labelled isonitrile compounds (sestamibi or tetrafosmin), have been proposed in patients with thyroid carcinoma, but results were not completely satisfactory (5,6). Positron emission tomography (PET) using [ 18 F]-2-fluoro-2-deoxy-D-glucose (FDG) is a promising technique for the detection of recurrences of differentiated thyroid cancer, especially in cases with no detected iodine uptake, but the method is expensive and may be not readily available (7,8).…”

Is [18F]-2-fluoro-2-deoxy-d-glucose (FDG) scintigraphy with non-dedicated positron emission tomography useful in the diagnostic management of suspected metastatic thyroid carcinoma in patients with no detectable radioiodine uptake?

“…Several radiopharmaceutics such as thallium-201 chloride, technetium-99m labelled isonitrile compounds (sestamibi or tetrafosmin) and [indium-111 DTPA D Phe]octreotide have been therefore proposed as a potential tool for the diagnosis of recurrences in thyroid carcinomas, but results have proved controversial with sensitivities depending on patient selection. In general, all these techniques are viable in the presence of a sizeable tumour but, having poor sensitivities, they are incapable of detecting micrometastases (2,(5)(6)(7)(8).…”