The first decision point facing the clinician is whether to perform fine-needle aspiration cytology out of concern that many of these nod- ules will be found to be papillary thyroid microcarcinomas (PTMC). Guidelines of the American Thyroid Association (ATA) are clear on this point with recommendations that nodules larger than 1 cm should undergo fine-needle as- piration and that smaller nodules should be biopsied on the basis of finding suspicious ultrasonographic findings such as calcification, increased Doppler flow, solid or hy- poechoic appearance, irregular or blurred margins, intra- nodular vascularity on Doppler, or a taller than wide shape, and also if there is a history of radiation exposure or a family history of thyroid cancer (1). That a given nodule may be malignant can be signaled by uptake on an 18F-fluoro-deoxyglucose scan on positron emission to- mography (2) and is based on the presence of an increased number of Glut transporters in cancer cells. One reason for the increasingly frequent detection of these incidental thy- roid cancers is the growing use of positron emission to- mography scans (3, 4).
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