Utility of BRAF mutation detection in fine-needle aspiration biopsy samples read as "suspicious for papillary thyroid carcinoma".

Abstract

The purpose of this study was to evaluate the diagnostic utility of BRAF mutation testing on thyroid nodules "suspicious for papillary thyroid carcinoma" (PTC) cytology. A chart review of patients with fine-needle aspiration (FNA) results "suspicious for PTC" with subsequent thyroidectomy was performed. Corresponding archived FNA slides underwent BRAF mutation testing. Sixty-six patients with FNA "suspicious for PTC" underwent thyroidectomy. Forty-two (63.6%) had PTC diagnosed on final histopathology, whereas 21 (31.8%) had benign findings. Thirty-five patients (83%) with histologically proven PTC underwent total thyroidectomy, whereas 7 (17%) underwent hemithyroidectomy. BRAF mutation was detected in 17 of 49 samples (34.6%) available for testing and had 45.5% sensitivity, 87.5% specificity, 88.2% positive predictive value (PPV), and 43.8% negative predictive value (NPV) for diagnosing PTC. Two of 4 patients (50%) who underwent hemithyroidectomy with subsequent completion thyroidectomy had mutated BRAF detected. BRAF testing is a useful adjunct to improve PPV for patients with "suspicious for PTC" cytology.