Sentinel Node Biopsy for the Detection of Head and Neck Melanoma: A Review

Abstract
Worldwide incidence of malignant melanoma is on the rise. Early detection of this malignancy is key to survival, and in the case of more advanced malignancy, early and effective detection of micrometastatic disease is crucial for staging and therapy. Because melanoma spreads primarily via lymphatic drainage patterns, effective methods for tracing these pathways are of paramount importance. The authors summarize the efficacy of blue dye, gamma probe, and lymphoscintigraphy detection methods, both individually and combined; the “missed disease” (or false-negative) rate; and the clinical discordance between expected and actual location of metastatic disease in head and neck melanoma. A clinical meta-analysis of current studies in head and neck melanoma was used to evaluate clinical data. A success rate of 95% to 100% for detection of sentinel lymph nodes can be achieved when blue dye, gamma probe, and lymphoscintigraphy techniques are combined. This is associated with a false-negative rate of 7.7% to 10.4%. With respect to intermediate-depth melanomas of the head and neck, a significant discordance exists between expected and actual lymphatic drainage patterns. This problem is best addressed using a combination of lymphoscintigraphy, blue dye, and gamma probe localization, which yields a success rate of 95% to 100% for detection of sentinel lymph nodes and a low false-negative rate of 7.7% to 10.4%. In the instance of a failed study, one in which sentinel nodes are not detected by the aforementioned methods, elective node dissection is the treatment modality of choice.