Diagnostic accuracy of [99mTc]Tc-Sestamibi in the assessment of thyroid nodules

// Anna Yordanova 1, * , Soha Mahjoob 1, * , Philipp Lingohr 2 , Jorg Kalff 2 , Andreas Turler 3 , Holger Palmedo 4 , Hans-Jurgen Biersack 1 , Glen Kristiansen 5 , Jamshid Farahati 6 , Markus Essler 1 and Hojjat Ahmadzadehfar 1 1 Department of Nuclear Medicine, University Hospital Bonn, Bonn, Germany 2 Department of Surgery, University Hospital Bonn, Bonn, Germany 3 Department of General and Visceral Surgery, Johanniter-Krankenhaus Bonn, Bonn, Germany 4 Institute of Radiology and Nuclear Medicine, PET-CT Center, Bonn, Germany 5 Institute of Pathology, University Hospital Bonn, Bonn, Germany 6 Department of Nuclear Medicine, Bethesda Hospital, Duisburg, Germany * These authors have contributed equally to this work Correspondence to: Hojjat Ahmadzadehfar, email: hojjat.ahmadzadehfar@ukbonn.de Keywords: sestamibi, MIBI, thyroid nodules, thyroid cancer, cold nodule Received: June 20, 2017 Accepted: September 16, 2017 Published: October 17, 2017 ABSTRACT [ 99m Tc]Tc-Sestamibi (MIBI) is an increasingly used tool for evaluation of thyroid nodules. However, there is a lack of evidence about the accuracy of this method in the European population. The aim of this study was to assess the utility of MIBI for the differentiation of thyroid nodules in a large cohort. 161 patients underwent MIBI, followed by a thyroidectomy. We used a dual phase MIBI protocol. Interpretation of the images included a scoring system from 0 (absent) to 3 (increased); this was to provide a scale for the uptake of the thyroid nodule in comparison to the paranodular tissue. Additionally, we evaluated the tracer uptake trend in late images compared to early images. We used the final histopathology as the reference standard. Scores 0-1 in early images, scores 0-2 in late images, and an absence of increasing uptake in the thyroid nodule in late images, showed the best predictive values to exclude malignancy, respectively (negative predictive value (NPV) 89%). Highest sensitivity (91%) for malignant nodules was evident in early images with a score 1-3. Highest specificity (91%) was obtained when the negative was defined as an absence of uptake-increase, in the late images. This study confirms that the most valuable feature of MIBI is the high NPV. Thus, with the appropriate interpretation method, high sensitivity and specificity, and moderate PPV can be obtained.