Diagnostic performance of utilizing a single-dye method for sentinel lymph node biopsy in papillary thyroid cancer

Link of Video Abstract: https://youtu.be/Xs6hpFJXL_4 Introduction: Even in the early stages of papillary thyroid cancer (PTC), central compartment lymph node metastases are frequently observed. Prophylactic central compartment neck dissection (pCCND) is still debatable in terms of its impact on the prognosis of the patient. By identifying the sentinel node (SN), which initially achieves lymphatic flow from its original tumour, Sentinel Lymph Node Biopsy (SLNB) utilizing a single dye procedure of methylene blue can be employed as an option for therapy. The study's objective was to assess the effectiveness of the SLNB approach in identifying central compartment metastases in PTC patients by utilizing methylene blue. Methods: A prospective study at Cipto Mangunkusumo Hospital was conducted between 2016 and 2017, enrolling 68 PTC patients (T1-T3, cN0). All patients underwent thyroidectomy and pCCND dissection following a perinodular injection of 1 cc methylene blue. The histological outcomes of the sentinel nodes (SNs) were compared with those of other lymph nodes in the central compartment. Result: 19% of cases of lymph node metastases to the central compartment. SNs were detected in 56 of 68 patients (82.3%). Of the 56 SLNs that were discovered, 13 had lymph nodes that were positive for metastases; 11 of them also had NSLNs that were positive for metastases. Positive NSLNs were not found in any of the patients with negative SLNs. In conjunction, SNs had a 100% negative predictive value (NPV) for central compartment metastases (95% confidence interval = 91.8–100) with no false negative rate. There was no evidence of recurrent laryngeal nerve damage or persistent hypoparathyroidism. Conclusion: SLNB using methylene blue was a significant predictor of NSLNs and can be used to select patients who would benefit from pCCND.