ABSTRACT
OBJECTIVE: To evaluate the clinical value of intraoperative nerve monitoring (IONM) by comparing the procedure times for thyroidectomies performed with and without IONM. METHODS: A prospective, randomized, controlled study was conducted on 32 patients (representing 41 nerves at risk) undergoing thyroidectomies carried out by two experienced head and neck surgeons (CC & WP). Sixteen thyroidectomies were performed without IONM (the "non-IONM group"), while 16 thyroidectomies were performed with IONM (the "IONM group"). The measured datapoints were setup time, time to visual identification of the recurrent laryngeal nerve (RLN), time to confirm the RLN electrophysiologically, dissection time, and total operative time. RESULTS: With both surgeons, the IONM group had shorter visual times to RLN identification than the non-IONM group (CC: 3.7 minutes vs 5.3 minutes; WP: 3.4 minutes vs 9.7 minutes). Additionally, the electrophysiological identification time for the IONM group was shorter than the visual identification time for the non-IONM group. The setup times, dissection times, and total operative times of the 2 groups did not significantly differ (P > .05). No RLN injuries were observed. CONCLUSIONS: IONM reduces the time needed for RLN identification in thyroidectomies. Functional RLN confirmation can reassure surgeons of the operative results. Moreover, use of IONM does not significantly impact setup and total operative times. LEVEL OF EVIDENCE: 2.
ABSTRACT
PURPOSE: Fine-needle aspiration biopsy (FNAB) is regarded by the Bethesda system as the gold-standard investigation for stratifying the risk of malignancy of a thyroid nodule. However, some limitations affect the adequacy of the obtained materials, resulting in 30% of the cytological results remaining in the indeterminate category. We aimed to investigate the diagnostic value of the BRAF mutation in cytologically indeterminate thyroid nodules after the reclassification of a variant thyroid carcinoma. PATIENTS AND METHODS: In this prospective diagnostic study, 76 patients with FNAB findings of atypia of undetermined significance (AUS) and suspicious for malignancy (SUS) were included. The BRAF V600 mutation from FNAB was confirmed by a PCR-based method (Sanger sequencing combined with allele-specific real-time PCR techniques) and immunohistochemistry (IHC). Pathological specimens and features, including noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), were reviewed and compared to the FNAB results. RESULTS: Using the PCR-based method, the BRAF mutation was positive in 13/76 cases (17.1%), with the diagnostic values of 16.7% sensitivity, 100% specificity, 100% positive predictive value (PPV), and 82.8% negative predictive value (NPV) in the AUS compared to 73.3% sensitivity, 100% specificity, 100% PPV, and 20% NPV in the SUS. For the IHC technique, only 20 of the 76 cytological specimens were qualified for testing. The BRAF mutation was positive in 13/20 cases, with the diagnostic values of 100% sensitivity, 63.6% specificity, 42.9% PPV, and 100% NPV in the AUS compared to 100% sensitivity and PPV in the SUS. The BRAF mutation was not found in the pathological reports for NIFTP. CONCLUSION: The malignancy rate is high in our data, with specific and acceptable accuracy rates for the BRAF mutation from FNAB found by using the PCR-based method. NIFTP has been introduced after the pathological reclassification. Molecular diagnosis might be useful to establish the nature of the disease.
