Multiple non-malignant iodine uptake in a 131I whole body scan of a patient with papillary thyroid carcinoma: Importance of SPECT/CT

Document Type : Case Report

Authors

1 Nuclear Medicine Research Center, Mashhad University of Medical Science, Mashhad, Iran

2 Nuclear Medicine and Molecular Imaging Department, Imam Reza International University, Mashhad, Iran

Abstract

After thyroidectomy in papillary thyroid carcinoma (PTC) patients, whole body radioiodine scan (WBIS) is necessary for localization of any abnormal radioiodine avid lesions. However false-positive radioiodine uptake in WBIS can be problematic. We report a 32 years old female patient with PTC. After thyroidectomy and radioiodine therapy WBIS was performed. In her post therapy WBIS, there were zones of radioiodine uptake in the chest, mediastinum, and pelvic regions.  In SPECT/CT, we encountered simultaneous uptake of radioiodine in breast, thymus, adnexa and intrauterine device (IUD) site. SPECT/CT images could identify these potential false positive uptakes as benign accumulations of the tracer.

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