Endocrine Abstracts

Introduction: Patients bearing thyroid cancer that have already gone into surgery and 131I therapy that in the follow-up have high thyroglobulin levels and negative 131I whole body scan represent a diagnostic and therapeutic challenge. 99mTc HYNIC Octreotide recognizes somatostatin receptors that are expressed in thyroid cancer. The objective of this paper is to evaluate these patients by means of 99mTc HYNIC Octreotide and to correlate the results with other imaging methods.

Materials and methods: 99mTc HYNIC Octreotide scintigraphy was performed to 20 patients bearing diferentiated thyroid cancer (16 papillary and 4 follicular) postthyroidectomized with raised thyroglobulins (2.5 to 114 ng/ml mean 15.7 ng/ml) and negative whole body scans (18 women and 2 men, age 18–72 years). Studies were performed after obtaining informed consent. Images started 2, 4 and 24 h after the injection of 900 MBq of 99mTc-HYNIC Octreotide, performing a whole-body scan followed by a SPECT acquisition of the region of interest. A double detector gamma camera equipped with LEHR collimators (Mediso Nucline Spirit DH -V, Hungary) was used. Three-dimensional images were co- registered with CT scans in order to define better the abnormal 99mTc HYNIC Octreotide uptake using software fusion imaging.

Results: 99mTc HYNIC Octreotide allowed us to detect abnormal areas in 17 patients, being 3 negatives. We could correlate these results with computed tomography in 12 of them. We found tomographic alterations that corresponded to the abnornal 99mTc HYNIC Octreotide uptake in 7. In the remainging 5 we didn’t find an anatomic alteration. In all cases, SPECT-CT fusion images allowed a better diagnostic confidence by providing anatomic correlation.

Conclusions: These preliminary results highlight the role of 99mTc HYNIC Octretide as a potencial radiopharmaceutical method that could aid in the diagnosis of these thyroid cancer patients. Also this information can be used to plan radioguided surgery or radionuclide therapy with 177Lu somatostatin analogues.

Conclusions: These preliminary results highlight the role of 99mTc HYNIC Octretide as a potencial radiopharmaceutical that could aid in the diagnosis of these thyroid cancer patients. Also this information can be used to plan radioguided surgery or radionuclide therapy with 177Lu somatatin analogues.