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Use of Sentinel Lymph Node Biopsy for Melanoma of the Head and Neck

Sentinel lymph node biopsy (SLN) is a well-accepted procedure for truncal and extremity melanoma (T&E). However, its role in melanoma of the head and neck (H&N) remains controversial. Complex lymphatic and vascular drainage make SLN more challenging in this region. This study was done to evaluate the results of SLN for H&N versus T&E melanoma. Three hundred sixteen patients who underwent SLN for melanoma using a double indicator technique were identified from a prospective database. Records were analyzed retrospectively. Statistical analysis was performed using χ2, t test, or Mann-Whitney U test to evaluate the results, as appropriate. H&N was found in 87 cases (27.5%). The mean age was 63.2 and 53.2 years for H&N and T&E melanoma (P < 0.001), respectively. 99Technetium positivity (89.7% H&N versus 99.6% T&E, P < 0.001) and isosulfan blue positivity (85.1% H&N versus 91.7% T&E, P = 0.08) were more likely in T&E melanoma. There was a significant difference between H&N and T&E melanoma with respect to the incidence of failed SLN, defined as no sentinel nodes identified intraoperatively (8.0% versus 0%, P < 0.001). Both groups had similar rates of positive intraoperative imprint cytologic examination (4.6% H&N versus 6.1% T&E, P > 0.5). There was a trend suggesting a higher mean number of sentinel lymph nodes found (3.1 versus 2.7, P = 0.1) in H&N melanoma. The total number of lymph nodes found in dissection specimens (20.9 versus 21.9, P = 0.45), the total number of positive lymph nodes (3.5 versus 1.6, P = 0.32), the incidence of any recurrence (19.5% versus 12.7%, P = 0.2), and time to recurrence (14.2 versus 20.6 months, P = 0.18) were similar between H&N and T&E melanoma. SLN mapping of H&N lesions is more difficult than at other sites. However, rates of nodal positivity are similar to melanoma of the trunk and extremities. Therefore, despite being more demanding, SLN is useful in diagnosis and treatment of melanomas of the head and neck.