Analysis of regional recurrence after negative sentinel lymph node biopsy for head and neck melanoma.

BACKGROUND The head and neck have a rich lymphatic drainage and complex anatomy, which complicate sentinel lymph node (SLN) biopsy for melanoma. The incidence of regional recurrence after a negative SLN biopsy has been shown to be higher than that at other sites. Compounding factors in this scenario were analyzed to determine their impact on both SLN status and survival. METHODS A retrospective review of a prospective database of 315 patients who underwent SLN biopsy for head and neck melanoma from 1994 to 2009 was performed. A false-negative SLN biopsy was defined as a regional recurrence in a previously mapped nodal basin. RESULTS In all, 267 patients (84.8%) were SLN negative (SLN-) and 48 patients (15.2%) were SLN positive (SLN+). The false-negative SLN biopsy occurred in 17 patients (6.4%). The mean follow-up was 37.6 months (3-152 months). The false-negative SLN and SLN+ patients were similar with respect to patient age and sex and primary melanoma tumor thickness and ulceration. The site of the primary melanoma and the lymphatic drainage patterns did not influence the false-negative biopsy rate. The mean survival was SLN- 119.3 months (95% confidence interval [CI], 106.1-132.5, p < .001), SLN+ 73.4 months (95% CI, 52.3-94.4), and the false-negative SLN 70.7 months (95% CI, 54.2-87.1). CONCLUSIONS The risk of a false-negative SLN biopsy in head and neck melanoma is independent of primary site and lymphatic drainage pattern. Patients with head and neck melanoma who have a regional recurrence after a negative SLN biopsy do not have a worse survival than that of patients who are initially SLN positive.