The Diagnostic Performance of Afirma Genomic Sequencing Classifier in Black and Hispanic Patients With Indeterminate Thyroid Nodules.

About 20% of thyroid nodules detected on ultrasound are cytologically indeterminate (Bethesda categories III and IV), but the rate of malignancy of these nodules is less than 36%. The ability of Afirma Genomic Sequencing Classifier (GSC) to further risk-stratify indeterminate thyroid nodules among Black and Hispanic patients is understudied. Retrospective Chart Review. Two Academic Medical Centers. Black and Hispanic patients who underwent Afirma GSC from 2017 to 2024 were included. Demographics, clinical history, GSC results, and surgical pathology reports were captured. Univariate analysis was conducted to elucidate demographic and clinical characteristics of this population, and confusion matrices evaluated GSC test performance. 160 patients were included in this cohort with a median age at diagnosis of 51 years, 142 (88.8%) females, 86 (53.8%) Black, and 74 (46.2%) Hispanic. Median nodule size was 2.4 cm, 167 were Bethesda III, and 17 were Bethesda IV. Of the 184 Bethesda III and IV thyroid nodules tested with GSC, 131 (71.2%) were reported as benign. In total, 59 nodules (29.4%) were resected, with 19 malignancies. The observed values of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 89.5%, 78.2%, 32.1%, and 98.5%. For all specimens with oncocytic cytology (n = 45), the sensitivity, specificity, PPV, and NPV were 83.3%, 69.2%, 29.4%, and 96.4%, respectively. This represents the largest study of Afirma GSC involving Black and Hispanic patients. In this cohort, the diagnostic performance of the Afirma GSC was comparable to that observed in the original validation study.