Gene expression classifier

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A gene expression classifier (GEC) test is a developing technology in the analysis of indeterminate thyroid nodules, using cells from a fine needle aspiration. The most common commercially available GEC in the United States is known as AFIRMA.

The test is designed to use molecular markers to help classify "indeterminate" thyroid nodules, and therefore avoid surgery for indeterminate nodules that are actually benign.

If the GEC test result is benign then the sensitivity of the test is high enough to achieve a negative predictive value of 94-95% in:

atypical or follicular lesion of undetermined significance
follicular neoplasm or lesion suggestive of follicular neoplasm

The GEC test does not have a role when there is a definitive result (either benign or malignant) on the original FNA aspiration.