[The evaluation of 123I-MIBG scintigraphy in medullary thyroid carcinoma (MTC)].

The diagnostic value of 123-I-MIBG (meta-iodobenzylguanidine) scintigraphy was investigated in six patients with recurrence and/or metastatic spread of a medullary thyroid carcinoma. In no case was there MIBG storage in tumor tissue. Thus, our results show that MIBG scintigraphy is not suitable as a screening method either in the primary diagnostics or the follow-up of medullary thyroid carcinoma. If, however, inoperable metastases have been detected by other diagnostic methods, MIBG scintigraphy is indicated in order to test a potential therapeutic application in these patients. In the imaging diagnostics and follow-up of medullary thyroid carcinoma, the examination with 99mTc(V)-DMSA (technetium-99m-dimercaptosuccinate) is markedly superior to MIBG scintigraphy. High-resolution cervical sonography is of major importance in the hands of an experienced examiner.