3.　Head and Neck International Symposium: Korea-Japan Joint Session

Neck node metastasis of head and neck cancer is the most important prognostic factor, which could affect the rates of survival and recurrence.Therefore, accurate diagnosis of metastatic neck lymph nodes is essential for treatment planning and prognosis assessment.To date, various imaging modalities including ultrasonography(US) , computed tomography(CT) , magnetic resonance imaging(MRI) , and, most recently, positron emission tomography(PET) -CT have failed to show sufficient accuracy to detect occult metastasis.As a result, the concept of elective neck dissection(END) has become the mainstay of treatment for clinically negative neck node(cN0)head and neck squamous cell carcinoma (HNSCC) , despite the knowledge that up to 80 of patients will not benefit from END, which is why some clinicians support a wait-and-see policy.Sentinel lymph node biopsy(SLNB)is gaining ground to become an alternative to elective neck dissection with the ability of more accurate neck staging in cN0 HNSCC.Validation studies of SLNB in cN0 HNSCC reported a high accuracy rate with simultaneous neck dissection and/or short-term follow-up as reference standard.A recent meta-analysis of 26 studies reported a sensitivity of 95 and negative predictive value of 96 for SLNB in HNSCCC.In the few longterm follow-up studies reporting the outcomes of SLNB application trials in which neck dissection was performed only for positive SLNs, excellent accuracy and oncological results were reported.In this session, up to date development as well as oncologic safety and outcomes of SLNB will be addressed.