¹¹¹In-pentetreotida en el diagnostico de localizacion de la recidiva del carcinoma medular de tiroides

Detection of recurrence from medullary thyroid carcinoma (MTC) remains a diagnostic problem, specially when increased serum tumour marker levels suggest recurrence and conventional imaging techniques are non diagnostic. In this study we performed somatostatin receptor scintigraphy (¹¹¹In- pentetreotide) and CT (computed tomography)/MR (magnetic resonance) in a series of 20 patients with MTC presenting with elevated serum tumour markers after surgery. ¹¹¹In-pentetreotide whole body studies detected tumour in 9 of the 20 patients studied and detected 12 tumoral localizations. CT/MR detected turnout in 8 of the 18 patients studied and detected 13 tumoral localizations. ¹¹¹In-pentetreotide detected recurrence in all patients with basal calcitonin levels above 650 ηg/L. We conclude that ¹¹¹In- pentetreotide studies have limited sensitivity to detect recurrence in patients with MTC, although their sensitivity may improve with high serum calcitonin levels. These radionuclide imaging techniques should be employed when conventional imaging techniques are negative or inconclusive. ¹¹¹In- pentetreotide studies should be employed when the presence of somatostatin receptors need to be investigated to provide the basis for treatment with somatostatin analogues.