EVALUATION OF TECHNETIUM-99M-MIBI SCINTIGRAPHY IN METASTATIC DIFFERENTIATED THYROID-CARCINOMA

Technetium-99m-methoxyisobutyl isonitrile (Tc-99m-MIBI) was evaluated for its ability to detect metastases from thyroid carcinoma. Methods: Twenty-seven thyroidectomized patients with metastatic differentiated thyroid carcinoma, of whom 20, 9 and 12 had lung, lymph node and bone metastases, respectively, were examined with Tc-99m-MIBI. The scan res ults were compared with those of (TI)-T-201 and I-131 whole-body scans . Results: Increased accumulation of Tc-99m-MIBI was observed in lung metastases of 15 patients (75.0%), 12 lymph node metastases (100.0%) a nd 29 of 31 bone metastases (93.5%). Increased accumulations of Tl-201 and I-131 scans were seen in, respectively, 16 (80.0%) and 17 (85.0%) of the 20 patients with lung metastases, 12 (100.0%) and 5 (41.7%) of the 12 lymph node metastases and 28 (90.3%) and 27 (87.1%) bone metas tases. Because of its better image quality, Tc-99m-MIBI detected more lesions in the lung (n = 38) than (TI)-T-201 did (n = 17). Conclusion: Technetium-99m-MIBI is clinically useful for detecting metastases fro m differentiated thyroid carcinoma and deserves clinical application i n the postoperative follow-up of such patients.