Clinical experience following implementation of routine SPECT-CT imaging following 131-iodine administration for thyroid cancer

Abstract

Background: Planar scintigraphy has long been indicated in patients receiving I-131 therapy for thyroid cancer to determine the anatomic location of metastases. We studied our experience upon implementing additional SPECT-CT scanning in these patients. Method: We performed a retrospective study of consecutive adult patients with newly diagnosed thyroid cancer treated with I-131 between 2011 and 2017. Radiologic findings detected with planar scintigraphy alone versus those identified with SPECT- CT scanning were primary endpoints. Result: 212 consecutive patients with thyroid cancer were analyzed in two separate cohorts (107 planar scintigraphy alone;105 planar scintigraphy with SPECT-CT). The addition of SPECT-CT resulted in more findings, both thyroid-related and incidental. However, we identified only 3 of 21 cases in which SPECT- CT provided unequivocal additional benefit by changing clinical management beyond planar scintigraphy alone. No difference in the detection of distant metastatic disease or outcome was identified between cohorts. Conclusion: Synergistic SPECT-CT imaging in addition to planar nuclear scintigraphy adds limited clinical value to thyroid cancer patients harboring low risk of distant metastases, while frequently identifying clinically insignificant findings. These data from a typical cohort of patients receiving standard thyroid cancer care provide insight into the routine use of SPECT-CT in such patients.

Diagnostic Performance of [18F]TFB PET/CT Compared with Therapeutic Activity [131I]Iodine SPECT/CT and [18F]FDG PET/CT in Recurrent Differentiated Thyroid Carcinoma

“…In contrast, [ 131 I]iodine TxWBS-SPECT/CT is an excellent imaging modality and has previously not been compared with [ 18 F]TFB-based imaging ( 22 ). However, patients are exposed to significantly higher radiation levels from [ 131 I]iodine, and WBS-SPECT/CT has limited spatial resolution ( 23 ). Moreover, RAI has a variety of dose-dependent acute and long-term side effects, like adverse effects on the salivary and lacrimal glands up to secondary malignancies after repeated high activity of RAI ( 24 , 25 ).…”