Background:-Thyroid nodule is common, malignancies found in ≈ 9-15% of the nodules evaluated with FNAB (1). High resolution US and FNAB are the most important steps in diagnostic workup of thyroid nodule. 20–40% of FNABs yield undetermined cytology (2). Surgery is required in indeterminate FNAB, but only quarter of them prove to be malignant after surgery (3), so 77% underwent unneeded surgery. so, finding a mean to diagnose malignant nodule preoperative is important. advances in molecular genetics can be applied to develop a new diagnostic markers for FNA samples.Objective:- evaluating the diagnostic value of high resolution U/S, FNAC, and BRAFV600 in diagnosing malignant thyroid nodules. Patients and Methodology: 50 patients from Kasr alainy endocrine outpatient clinic with solitary or multiple thyroid nodules, All subjected to Full history and examination, thyroid profile, high resolution neck U/S, U/S guided FNAC and BRAFV600E analysis on FNAB using DNA sequencing then HRMA for confirmation Results: - The incidence of BRAFV600E mutation among PTC patients was 55.6%, P value < 0.001. The sensitivity of BRAFV600E mutation was 42.9%, specificity was 100%. Ultrasound sensitivity in detecting malignancy was 88.2%, specificity 72.7%. Addition of ultrasonography to BRAFV600E analysis increased ultrasound sensitivity in detecting PTC preoperative to 92%.There was a positive correlation between most suspicious ultrasonography findings and presence of BRAFV600E mutation (increased AP/T diameter, Increase intra-nodular blood flow, cervical lymphadenopathy, absent or incomplete halo (all p value < 0.001), irregular border p value 0.004 , micro calcifications p value 0.007.
Conclusion1-High resolution US and FNAB are the most important steps in diagnosis of thyroid nodule.2-BRAFV600E mutation detected mainly in PTC.3- Adding BRAFV600E analysis to U/S and FNA will increase the sensitivity of preoperative diagnosis of PTC especially in indefinite nodules. 4-BRAFV600E positivity was associated with most known suspicious U/S finding and significantly present in cases with cervical lymphadenopathy that may give it a prognostic value.5-HRMA is simple, accurate, low cost tool for BRAFV600E analysis.
