The majority of FNAs of tyroid nodules show benign histological findings but some are indeterminate or non-diagnostic. In an attempt to separate out patients with a worse prognosis, Afirma has develoiped a proprietory tests, Benign Gene Expression Classifier. In 2010, two modest-sized validation studies showed that the AGEC test could identify a benign gene expression signature in indeterminate cytology thyroid FNA samples with a negative predictive value >95%.
Independent evaluations of the test have been positive. Palmetto Government Benefits Administrators (Palmetto GBA), the CMS Medicare Administrative Contractor with oversight for the Afirma GEC, has published its assessment of the test as an update to its local coverage article on molecular diagnostics. This review determined that the test meets criteria for analytical and clinical validity, and clinical utility as a reasonable and necessary Medicare benefit, effective January 1, 2012.25. As part of the CLIA Laboratory licensure process, the analytical and clinical validation data for the Afirma GEC were independently assessed by reviewers from the California Department of Public Health and the New York State Department of Health.26,27 Both of these reviews resulted in a favorable licensure outcome.
The National Comprehensive Cancer Network (NCCN) thyroid carcinoma guidelines were updated in December, 2012 to state “Molecular diagnostics may be useful to allow reclassification of follicular lesions (follicular neoplasm or follicular lesion of undetermined significance) as more likely to be benign or more likely to be malignant…If molecular testing predicts a risk of malignancy comparable to the risk of malignancy seen with a benign FNA cytology (approximately 5% or less), consider observation.” The NCCN guidelines for abnormal gene/gene expression profile testing are associated with Level of Evidence 2A (lower level evidence, uniform NCCN consensus that the intervention is appropriate)
Daniel S. Duick et al, The Impact of Benign Gene Expression Classifier Test Results on the Endocrinologist–Patient Decision to Operate on Patients with Thyroid Nodules with Indeterminate Fine-Needle Aspiration Cytopathology, Thyroid. 2012 October; 22(10): 996–1001.
Syed Z. Ali, etal, Use of the Afirma® Gene Expression Classifier for Preoperative Identification of Benign Thyroid Nodules with Indeterminate Fine Needle Aspiration Cytopathology, PLoS Curr. 2013 February 11; 5