Immunocytochemistry Test of Protein BRAF Expression for Diagnosis of Well Differentiated Thyroid Carcinoma

Abstract

Background: Thyroid carcinoma generally has a good prognosis. The main focus of current research on thyroid carcinoma is to increase the accuracy of preoperative diagnosis of thyroid nodules. When the result of fine needle aspiration biopsy (FNAB) is indeterminate, clinicians often have doubts in determining the surgical management. Objective: Protein BRAF expression analysis can help improve the accuracy of FNAB and optimize the management of differentiated thyroid carcinoma. Methods: This study is a diagnostic test performed from October 2016 at Sanglah General Hospital with 38 patients as subjects who fulfilled the inclusion criteria. Data is being presented in descriptive form before diagnostic test is done to determine sensitivity, specificity, positive predictive value, negative predictive value and the accuracy of immunocytochemistry test for BRAF on indeterminate thyroid nodule. Results: Thirty-eight samples met the inclusion criteria during the study period. Three samples were male (7.9%) and 35 samples (92.1%) were female. The mean age of the sample was 45.21 years (SD ±10.910 years) with ages ranging from 23 to 66 years. Of the 12 samples undergoing isthmolobectomy, 7 samples (58.4%) were determined to be malignant from histopathological results. The sensitivity value of BRAF immunocytochemistry test is 45.45% with a specificity value of 81.25%, a positive predictive value of 76.92%, a negative predictive value of 52% and an accuracy of 60.50%. Analysis of the receiver operator (ROC) curve shows the area under the curve (AUC) of 63.4% with a confidence interval of 45.5–81.2%. Conclusion: Immunocytochemistry BRAF test have a reliable diagnostic value and can be taken into consideration in the preoperative diagnosis of thyroid malignancies.