Controversies in the Management and Followup of Differentiated Thyroid Cancer: Beyond the Guidelines
Table 1
Variables determined during follow-up that predict response to therapy (Tg thyroglobulin) (adapted from [4]).
Excellent response
Acceptable response
Incomplete response
Suppressed Tg
Undetectable
Detectable but <1 ng/mL
>1 ng/mL
Stimulated Tg
Undetectable
<10 ng/mL
>10 ng/mL
Trend in suppressed Tg
Remains undetectable
Declining
Stable or rising
Anti-Tg antibodies
Absent
Absent or declining
Persistent or rising
Neck examination
Normal
Normal
Palpable disease
Neck ultrasonography
No evidence of disease
Nonspecific changes in thyroid bed, Stable millimeter sized cervical LN even if abnormal by US criteria
Evidence of structurally significant recurrent/persistent disease in the thyroid bed (>1 cm), cervical lymph nodes (>1 cm), or distant metastases, particularly if structurally progressive or FDG avid
Diagnostic RAI WBS
No evidence for RAI avid disease
No evidence for RAI avid disease, very faint uptake in thyroid bed only
Persistent/recurrent RAI avid disease present
Cross-sectional imaging (MRI, CT)
No evidence of disease
Non-specific changes
Structural disease present
FDG PET scanning
No evidence of disease
Non-specific changes consistent with normal variants or inflammatory changes
