MedStar Authors catalog › Details for: Use of <sup>99m</sup>Tc-sestamibi SPECT/CT when conventional imaging studies are negative for localizing suspected recurrence in differentiated thyroid cancer: a method and a lesson for clinical management.
Use of <sup>99m</sup>Tc-sestamibi SPECT/CT when conventional imaging studies are negative for localizing suspected recurrence in differentiated thyroid cancer: a method and a lesson for clinical management.
Citation: Endocrine. 2018 May 24.Journal: Endocrine.Published: 2018ISSN: 1355-008X.Full author list: Wu D; Ylli D; Gomes Lima CJ; Lee W; Burman KD; Wartofsky L; Van Nostrand D.UI/PMID: 29797211.Subject(s): IN PROCESS -- NOT YET INDEXEDInstitution(s): MedStar Health Research Institute | MedStar Washington Hospital CenterDepartment(s): Pathology | Medicine/Endocrinology | Medicine/Nuclear MedicineActivity type: Journal Article.Medline article type(s): Journal ArticleDigital Object Identifier: https://dx.doi.org/10.1007/s12020-018-1636-y (Click here)Abbreviated citation: Endocrine. 2018 May 24.Abstract: PURPOSE: The detection of recurrent disease in differentiated thyroid cancer (DTC) patients with elevated or rising serum thyroglobulin (Tg) levels and multiple negative conventional imaging studies can be challenging, especially when <sup>18</sup>F-FDG PET/CT scan is also negative. We report a patient and review the literature on the diagnostic use of <sup>99m</sup>Tc-sestamibi scans to identify the source of elevated or rising Tg in patients with negative conventional imaging including negative <sup>18</sup>F-FDG PET/CT scans.Abstract: PATIENT AND METHODS: A 73-year-old woman was referred for widely-invasive metastatic follicular thyroid cancer with bone metastasis to her left mandible. She had a total thyroidectomy, left mandibular resection, and <sup>131</sup>I therapy of 145mCi (5.4GBq) and her subsequent unstimulated serum Tg level was 29ng/ml (TgAb negative). At six months' follow-up, her stimulated Tg was 527ng/ml (TSH 188mIU/L, TgAb negative). All imaging studies performed within the prior 12 months were reported as negative for recurrence or metastasis; this included neck ultrasound, diagnostic radioiodine scan, chest CT and, <sup>18</sup>F-FDG PET/CT. The patient was injected with 24.6mCi (910MBq) of <sup>99m</sup>Tc-sestamibi intravenously, and whole-body and SPECT/CT images were acquired.Abstract: RESULTS: The <sup>99m</sup>Tc-sestamibi whole-body posterior image demonstrated abnormal focal uptake in the right posterior calvarium and corresponded to an occipital lytic bone lesion on the SPECT/CT. The patient underwent surgical resection of the skull metastasis, and pathology confirmed metastatic follicular thyroid cancer. Five months post-surgery, the suppressed Tg was markedly reduced and remained stable at ~3.2ng/ml. With the knowledge of the DTC recurrence location, the two sets of <sup>18</sup>F-FDG images were re-evaluated. The more thorough and targeted interpretation underscored the importance of structured image reporting. The current literature on the utility of <sup>99m</sup>Tc-sestamibi scans when radioiodine, <sup>18</sup>F-FDG PET/CT, and other imaging studies are negative is sparse and inconsistent.Abstract: CONCLUSIONS: <sup>99m</sup>Tc-sestamibi may have a role in thyroid cancer localization when physical exam, neck ultrasound, radioiodine scan, chest/abdomen CT, and <sup>18</sup>F-FDG PET/CT does not identify the source of elevated Tg levels in DTC.