Î Though thyroid cancer is associated with high overall survival rates,
exceeding 90% for most subtypes, the risk of recurrence has been reported
to be as high as 35%.
Î Most of these recurrences are detected within the first five years after
diagnosis and thus may actually represent persistent rather than truly
recurrent disease.
Î It is known that the majority of reoperations for thyroid cancer are
preventable and that inadequate preoperative imaging frequently
is the root cause of incomplete initial surgery.
Î Ultrasound remains the most important imaging modality in the evaluation
of thyroid cancer and should be used routinely to assess both the primary
tumor and all associated cervical lymph node basins preoperatively.
Î Ultrasound evaluation (''mapping'') of bilateral lymph node compartments
1–6 should be performed routinely in the preoperative evaluation of patients
with definitive cytologic evidence of carcinoma (positive FNA).
Î Screening for distant metastasis is generally not performed prior to initial
surgery for differentiated thyroid cancers.
Functional Imaging
Î Functional imaging with positron emission tomography (PET), PET-CT or
PET-
18
F-fluoro-2-deoxyglucose is currently limited to the detection of
recurrent disease.
Key Points
Diagnosis
