False-positive radioactive iodine uptake in a large uterine fibroid

Document Type : Case Report

Authors

Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

Abstract

Incidental findings in the post-treatment whole body iodine scan (WBIS) sometimes have a broad list of differentials. We present a case of differentiated thyroid carcinoma (DTC), pT3aN1b, with family history of DTC. She was treated with adjuvant 131I therapy (5.55 GBq). The patient's post-treatment WBIS revealed a large, round iodine-avid area above the bladder, which was attributed to a massive uterine fibroid. Physical examination as well as radiologic correlation with SPECT/CT were also concordant. Fibroids can trap the radioiodine by various mechanisms. This case serves as a reminder of an uncommon pitfall in WBIS, particularly in women of reproductive age.

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Main Subjects


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