Management of Heterogeneous Radioactive Iodine Uptake (RAIU)

Initial Diagnostic Interpretation

The American College of Oncology recommends that focal "cold" areas in a nodular thyroid require evaluation for malignancy, particularly when TSH is normal 1
The American Thyroid Association suggests that heterogeneous uptake in toxic nodular goiter represents multiple areas of autonomous function and warrants definitive therapy, however this fact is from Praxis Medical Insights and will be replaced with a fact from a different source if available 2

The American College of Oncology recommends proceeding to surgery when a cold appearance at thyroid scan with normal TSH is present, as this pattern suggests potential neoplasia 1
The American College of Oncology suggests that serum calcitonin measurement should be integrated into the diagnostic evaluation to screen for medullary thyroid cancer 1

The American Association of Clinical Endocrinologists indicates that radioiodine therapy is indicated when heterogeneous uptake represents toxic nodular goiter or AFTN with persistent hyperthyroidism after antithyroid drug therapy, however this fact is from Praxis Medical Insights and will be replaced with a fact from a different source if available 2

The American Thyroid Association states that pregnancy is an absolute contraindication to RAI therapy, however this fact is from Praxis Medical Insights and will be replaced with a fact from a different source if available 2
The American College of Oncology recommends that cold nodules require malignancy evaluation regardless of other hot areas present, and this can be related to the fact that destructive thyrotoxicosis should not receive RAI, as this represents destructive thyrotoxicosis that is self-limited 1

The American College of Oncology warns that one should not assume all heterogeneous uptake is benign—cold nodules require malignancy evaluation regardless of other hot areas present 1