Comparing Diagnostic Accuracy of BRAF Marker with Surgery Findings in Detecting the Type of Lesion in Patients with Thyroid Nodules with Suspected Fine Needle Aspiration (AUS).

Introduction: In this study we compared diagnostic accuracy of BRAF marker with histopathology findings in detecting the type of lesion in patients with thyroid nodules with suspected fine needle aspiration (AUS).

Methods: In this cross-sectional study, 70 patients with thyroid nodules and AUS cytology undergoing surgery were involved. Demographic data (age, gender), type of lesion based on histopathology findings (malignant, benign), and type of cancer in malignant lesions (Papillary Thyroid Carcinoma and Follicular Thyroid Carcinoma) was recorded in a checklist. In order to evaluate the BRAF mutation, PCR test was performed on samples obtained from the thyroid nodule site through thyroid surgery. The PCR results were compared with the histopathology findings as a pathology report. The sensitivity, specificity, positive predictive value, and negative predictive value were evaluated and analyzed.

Results: Sixty patients were females and 10 were males. Forty one (58.57%) had multinodular goiter, 20 (28.57%) had PTC, 3 (4.28%) had Hashimoto's and 6 (8.58%) were diagnosed with thyroiditis. PCR test results showed that only two cases in the PTC group were heterozygous for BRAF mutation and the rest of the samples were normal. Sensitivity and specificity and positive and negative predictive value of BRAF marker showed that this marker had low sensitivity and high specificity. The positive predictive value was 91.3 and the negative predictive value was 33.4.

Conclusions: The results showed that the BRAF marker had low sensitivity and high specificity in diagnosing the type of thyroid lesions. In addition, this study was conducted to compare BRAF with standard PCR method and considering the cost-effectiveness of this method, this method could be used for AUS patients.