Sentinel node biopsy in head and neck desmoplastic melanoma: an analysis of 244 cases.

Abstract

Desmoplastic melanoma's low rate of sentinel lymph node (SLN) positivity and predilection for the head and neck region have led some to question the role of sentinel lymph node biopsy (SLNB) in patients with this rare histologic variant. Given desmoplastic melanoma's sarcoma-like histology and aberrant clinical behavior, we hypothesized that SLN status may not be indicative of outcomes in desmoplastic melanoma of the head neck. The objective of this study was to compare melanoma-specific survival among patients with head and neck desmoplastic melanoma based on SLN status. Retrospective analysis of patient data and outcomes using the Surveillance Epidemiology and End Results (SEER) database The SEER database was queried for patients who were diagnosed with desmoplastic melanoma and underwent SLNB. Clinicopathologic data and 5-year disease-specific survival (DSS) were compared among patients with positive and negative SLNs. We identified 244 patients with desmoplastic melanoma of the head and neck who underwent SLNB. Of these, only nine had positive SLNs (3.69%). Among the SLN-positive patients, five (55.6%) had scalp/neck tumors, three (33.3%) had ulcerated tumors, and tumor thickness ranged from 1.7 to 8.5 mm (mean, 4.8 mm). On univariable and multivariable analysis, SLN positivity did not significantly affect DSS in head and neck desmoplastic melanoma (P=.19 and P=.48, respectively). Our findings provide further evidence against routine SLNB in head and neck desmoplastic melanoma by demonstrating a lack of prognostic significance related to the procedure, and by confirming a significantly low rate of SLN positivity as well.