The role of technetium-99m sestamibi whole-body scans in diagnosing metastatic Hurthle cell carcinoma of the thyroid gland after total thyroidectomy: a comparison with iodine-131 and thallium-201 whole-body scans

Thirty-seven patients with Hürthle cell carcinoma of the thyroid gland underwent total thyroidectomy and then technetium-99m sestamibi (2-methoxyisobutylisonitrile), iodine-131 and thallium-201 wholebody scans. Twenty-two of them had elevated human serum thyroglobulin (HTg) levels. Among these 22 patients, abnormal uptake of ¹³¹I was seen in four (18.1%), abnormal uptake of ²⁰¹Tl chloride in 15 (68.1%), and abnormal ^99mTc-sestamibi accumulation in 18 (81.8%). No patients with normal levels had a positive whole-body scan. In comparison with the 1311 and 201T1 chloride images, the ^99mTc-sestamibi images were of superior quality and detected significantly more (P < 0.05) metastatic lesions of Hurthle cell carcinoma of the thyroid gland in patients with elevated HTg after total thyroidectomy. A mechanism is proposed that may explain these findings.