Accuracy and prognostic value of sentinel lymph node biopsy in head and neck melanomas

Debate remains around the accuracy and prognostic implications of sentinel lymph node biopsy (SLNB) for melanoma arising in the head and neck (HN) areas because several analyses have shown discordances between clinically predicted lymphatic drainage pathways and those identified by lymphoscintigraphy. This study assesses the accuracy and prognostic value of SLNB in this critical anatomic region.

Retrospective review of a prospectively collected melanoma database identified 331 patients with HN melanomas from January 2000 to December 2012. Primary end points included SLNB result, time to recurrence, site of recurrence, and survival. Multivariate models were constructed for analyses.

A sentinel lymph node (SLN) was identified in all 331 patients. There were 59 patients with a positive SLN (17.8%) with a recurrence rate of 88.1% compared with 22.4% in SLN-negative patients (P < 0.0001). The 5-y overall survival was 91.2% for SLN-negative patients and 48.7% for SLN-positive patients (P < 0.0001). Patients with scalp melanoma had thicker lesions and an elevated risk of SLN positivity, recurrence, and death compared with those with other sites. Among the 272 SLN-negative patients, four patients developed regional nodal disease in the same basin and had undergone a previous SLNB procedure for a false-omission rate of 1.45%. Risks for false-negative SLN occurrences included thick and scalp melanomas. Multivariate analysis on prognostic factors affecting relapse-free survival showed positive SLNB status to be the most prognostic clinicopathologic predictor of recurrence (hazard ratio, 20.56; P < 0.0001).

SLNB for patients with HN melanomas is an accurate procedure and has prognostic value.