16
Treatment
Recommendation 34
A. In patients with DTC in whom RAI remnant ablation or adjuvant
therapy is planned, preparation with recombinant human thyroid
stimulating hormone (rhTSH) stimulation is preferred over thyroid
hormone withdrawal. (S-H)
B. In patients with DTC of any risk level with significant comorbidity
that may preclude thyroid hormone withdrawal prior to RAI
administration, rhTSH preparation should be considered. (GPS)
C. If thyroid hormone withdrawal is planned prior to RAI therapy or
diagnostic testing, levothyroxine (LT4) should be withdrawn for three
to four weeks. If LT4 is withdrawn for ≥4 weeks, substitution of LT4
with liothyronine (LT3) in the initial weeks should be considered. In
such circumstances LT3 should be withdrawn for at least two weeks.
Serum TSH should be measured prior to radioisotope administration
to evaluate the degree of TSH elevation. (GPS)
D. A goal TSH of >30 mIU/L should be employed in preparation for RAI
therapy or diagnostic testing. (GPS)
E. In patients with known distant metastases, either LT4 withdrawal or
rhTSH can be used for preparation. (C-L)
Recommendation 35
➤ A low-iodine diet for approximately one to two weeks should be used
for patients undergoing RAI remnant ablation or treatment. (GPS)
Recommendation 36
➤ Postoperative diagnostic
123
I or low dose
131
I whole body scan (WBS)
may be considered for patients undergoing RAI treatment prior to
their therapeutic (ablative, adjuvant, or treatment) administration to
help guide treatment planning. (C-L)
Recommendation 37
➤ Post-RAI therapy scans should be performed after RAI treatment. (S-M)
Recommendation 38
➤ Single photon emission computed tomography with computed
tomography (SPECT/CT) may be performed when available with
diagnostic or post-treatment WBS. (C-L)
Recommendation 39
➤ Patients should be provided oral and written instructions before
preparation for RAI begins to minimize exposure to their families
and members of the public, consistent with guidelines in the country
where therapy is performed (e.g., in the U.S., those of the Nuclear
Regulatory Commission). (GPS)
