Afirma GEC and thyroid lesions: An institutional experience.

Area of Science:

• Endocrinology
• Oncology
• Molecular Diagnostics

Background:

• Thyroid fine-needle aspiration (FNA) is crucial for managing thyroid nodules.
• Bethesda categories III and IV present diagnostic challenges, often leading to uncertainty in patient management.

Purpose of the Study:

• To evaluate the performance of the Afirma Gene Expression Classifier (GEC) in classifying thyroid lesions within Bethesda categories III and IV.
• To assess the GEC's ability to differentiate benign from malignant thyroid nodules.

Main Methods:

• Retrospective analysis of medical records for patients with thyroid FNA and Afirma GEC results.
• Comparison of GEC results with final histologic diagnoses after thyroidectomy.

Main Results:

• The Afirma GEC yielded "nondiagnostic" results in 15.2%, "benign" in 33.3%, and "suspicious" in 51.5% of cases.
• Histologic analysis revealed malignancy in 16.7% of "nondiagnostic," 20% of "benign," and 55.6% of "suspicious" GEC results.
• Papillary carcinoma was the most frequent malignant tumor type, accounting for 39.5% of surgically confirmed cases.

Conclusions:

• Afirma GEC testing can help minimize unnecessary surgical interventions for thyroid nodules.
• GEC testing may be particularly valuable for fine-needle aspirations (FNA) classified as Bethesda category III.
• A conservative approach is recommended for "suspicious" Afirma GEC results when Hürthle cells are present in the FNA.