Diagnostic Value of 201Tl-chloride Scintigraphy for Thyroid Tumors

Among 114 patients with thyroid disease examined by ²⁰¹Tl-chloridescintigraphy, 101 were given a histological diagnosis. Of 28cases of thyroid carcinoma, 22 (78.6%) were positive. In threeof the 22, an obvious accumulation of ²⁰¹Tl-chloride was revealedin the metastatic lymph nodes of the neck and mediastinum. Only 12 of 50 (24%) cases of thyroid adenoma were positive.In comparison, all cases of hyperthyroidism and chronic thyroiditiswere positive and all cases of subacute thyroiditis were negative.The histological types of thyroid tumor were examined. Of 22cases of papillary carcinoma, 18 (81.8%) were positive. In fourcases which revealed negative figures, the tumor was almostcompletely encysted in three and the tumor was small in theother. Of the adenomas, eight cases of tubular adenoma and threeof trabecular adenoma were all positive, but colloid adenomaand thyroid cyst cases were all negative. It was concluded that ²⁰¹Tl-chloride has no specific affinityfor malignant tumors and cannot be used to discriminate betweencarcinoma and adenoma, but surgery should be indicated for noduleswhich are positive scanning by ²⁰¹Tl-chloride.