Is there a role for diagnostic scans in the management of intermediate-risk thyroid cancer?

Radioiodine (RAI) is selectively recommended for intermediate-risk differentiated thyroid carcinomas (DTC). The information gleaned from pretherapy stimulated thyroglobulin levels (sTg) and diagnostic 131I whole-body scans (DxWBS) to guide therapy remains controversial. The present study aimed at evaluating the impact of preablation sTg and DxWBS in the management of intermediate-risk DTC. A retrospective analysis of 301 intermediate-risk DTC patients submitted to total thyroidectomy and RAI therapy was performed. Pretherapy sTg and DxWBS and post-therapy WBS (RxWBS) findings were analyzed and compared to outcomes. Fifty-two patients (17.3%) had metastases diagnosed by DxWBS and/or RxWBS. The DxWBS identified 10.6% of patients with functioning metastases, including unexpected distant metastases. If combined with SPECT-CT, DxWBS detected RAI-avid metastases more frequently, particularly lymph node metastases (13.1% vs 4.2% planar WBS, P = 0.015). The DxWBS findings modified patient management in 8.3%. A pretherapy sTg