Afirma GSC: Challenges with repeat FNA

Some clinicians prefer to monitor and repeat a thyroid nodule FNA for patients with an initial indeterminate cytology result. The hope is that the follow up biopsy will provide more actionable information, such as a malignant or benign cytology result.

It’s important to note that within the Bethesda III cytology category, the concordance of interpretation within the indeterminate Bethesda III cytology category among different cytologists can be as low as 35%. Even when asked to re-evaluate their diagnosis in a blinded fashion, some cytologists don’t agree with their own initial diagnosis up to 40% of the time. 1

Though a repeat biopsy resulting in a Bethesda V or VI cytology would be clinically actionable, this only occurs about 2% of the time. The majority of nodules remain indeterminate. 2

Additionally, a benign cytology on repeat biopsy does not carry the same low risk of malignancy as an initial benign FNA result. In one study, the risk of malignancy in nodules with an initial indeterminate biopsy followed by a second benign biopsy was the same as those who had surgery after the initial indeterminate biopsy. 3

Based on these types of studies, the 2015 ATA guidelines state:

It’s important to note that within the Bethesda III cytology category, the concordance of interpretation within the indeterminate Bethesda III cytology category among different cytologists can be as low as 35%. Even when asked to re-evaluate their diagnosis in a blinded fashion, some cytologists don’t agree with their own initial diagnosis up to 40% of the time. 1 ”

For the best patient experience, we at Veracyte recommend collecting a sample for Afirma GSC on every nodule biopsy. In the event of acytology result that is not benign, the material is in hand for comprehensive Afirma molecular analysis. This prevents a repeat procedure, which adds cost and inconvenience to your patient and improving access into your clinic.