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

ABSTRACT

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: BRAF testing is a useful adjunct to improve PPV for patients with "suspicious for PTC" cytology.