By Pradeep K. Bhagat, MD, chairman, Department of Pathology
Effective immediately, the MLHL will start using Veracyte’s Afirma Genomic Sequencing Classifier test (GSC) for evaluation of the indeterminate thyroid cytology results (Bethesda categories III and IV).
The Afirma GSC is a next generation version of the Afirma Gene Expression Classifier test (GEC) which has been used by MLHL since 2014. Compared to GEC, GSC can identify 30% more benign nodules in a group of patients with indeterminate cytology findings.
Researchers validated the Afirma GSC on a prospective, multicentric, blinded cohort of 191 indeterminant thyroid nodule fine needle aspiration samples, the same sample set previously used to validate the first generation Afirma GEC. The Afirma GSC maintained the original tests high sensitivity (91% versus 90%) and significantly increased its specificity, from 52% to 68%.
The Afirma GSC identifies benign Hürthle cells, with increased specificity of 59%, compared with 12% with Afirma GEC.
In addition, the test provides classifiers for medullary thyroid cancer, the BRAF V600E variant and add classifiers to identify RET/PTC1 and RET/PTC3 fusions which are almost always associated with malignancy.
There is no change in specimen collection, ordering, reporting or cost.
Please see below report samples issued by Veracyte (these results will be reported in an addendum to the original cytology case as they currently are).
If you have any questions or concerns please contact Vlasta Zemba-Palko at 484-476-2608.