Between 34% and 44% of MCC cases arise in the head and neck region.1,3-6 This location presents unique challenges for SLNB due to complex lymphatic drainage patterns and proximity to critical anatomical structures.7,8 Accurate nodal staging is especially important because head and neck MCCs (HN MCC) may have worse prognoses than non−HN MCC.9,10
Prior studies of SLNB and HN MCC have been limited by small sample sizes (often 10 patients) and have reported relatively high false-negative rates.8, 11-13 A multisite retrospective study14 characterizing predictors of FN SLNB in stage I/II MCC included 214 patients with HN MCC and found a 39% FN rate in the HN cohort but did not otherwise analyze this cohort separately or describe the unique considerations associated with this region. High SLNB failure rates have also been observed in HN melanoma and squamous cell carcinoma and been largely attributed to anatomic complexity.15-17
In this large cohort study of patients with clinically node-negative HN MCC who underwent SLNB, we sought to evaluate SLNB accuracy within this anatomically complex region and to identify factors associated with SLNB failure and nodal disease. Our goal was to inform staging practices and refine risk stratification strategies to improve treatment planning and outcomes for this high-risk population.









