Numerous examinations have been reviewed, and moderately small-scale efforts pointed basically at the evaluation of the demonstrative adequacy of SLN biopsy in the head and neck,4 later investigations, including the SENT (Sentinel European Node Trial),5 have straightforwardly tended to the therapeutic advantage of this surgery. The study feasibility is focused primarily on the ability to recruit a sufficient number of patients within a reasonable timeframe. A 12% noninferiority margin was selected with a primary end point of 3-year overall survival. And selected a 10% noninferiority margin, with a primary end point of 2-year neck node recurrence-free survival (RFS).These studies were statistically powered to achieve sample sizes of approximately 250-300 patients . As a result it is acknowledged that recruitment challenges require an extension of the patient recruitment period. One may question whether 10% to 12% is an acceptable difference or range in performance, as related to outcomes for surgical procedures. With regard to the clinical application of the findings from this study, we noted that 12.5% (35 of 279) of the analyzed patients had oropharyngeal disease.

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