Procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer (version 3)

Version 3 of the procedure guideline for I-131 whole-body scintigraphy (WBS) is the counterpart to the procedure guideline for radioiodine therapy (version 3) and specify the interdisciplinary guideline for thyroid cancer of the Deutsche Krebsgesellschaft concerning the nuclear medicine part. I-131 WBS 3-6 months after I-131 ablation remains a standard procedure in an endemic area for thyroid nodules and the high frequency of subtotal surgical procedures. Follow-up without (131) I WBS is only justified if the following preconditions are fulfilled: low-risk group pT1 -2, pNO MO with histopathologically confirmed pNO, 1311 uptake <2%, 7311 WBS during ablation without any suspicious lesion, stimulated thyroglobulin (Tg)-level 3-6 months after ablation <2 ng/mL, and absence of anti-thyroglobulin-antibodies with normal recovery-testing. If patients from the low-risk group show normal I-131 WBS 3-6 months after ablation and stimulated Tg is of <2 ng/mLthere will be no need for additional routine 1311 WBS. If patients from the high-risk group show normal 1311 WBS and stimulated Tg-level of <2 ng/mL3-6 months after ablation, the follow-up care should include repeated stimulated Tg-measurements. If the Tg-level remains below 2 ng/ml, an additional 1311 WBS will be not necessary. The recommended intervals for stimulated Tg-testing are adopted to the prior intervals for I-131 WBS-testing in the high-risk group. Increased anti-thyroglobulin-antibodies or incomplete recovery-testing make an individual strategy of follow-up care necessary, which include I-131 WBS.