Predicting residual lymph node basin disease in melanoma patients with sentinel lymph node metastases

BACKGROUND: The incidence of residual occult disease in nonsentinel lymph nodes (NSLN) after a positive sentinel lymph node (SLN) biopsy in patients with melanoma is relatively low. The purpose of this study is to identify factors that may be predictive of occult NSLN metastases after positive SLN biopsy. METHODS: Fifty-six consecutive melanoma patients with positive sentinel nodes who subsequently underwent complete lymph node dissection (CLND) were evaluated. RESULTS: Only the number of positive SLN predicted the status on NSLN by univariate (P = 0.008) and multivariate (P = 0.028) analyses. None of the other variables (characteristics of SLN metastases, number of draining nodal basins, age, sex, thickness, Clark level, ulceration, number of mitoses/mm(2), histological subtype, and location of the primary) significantly predicted CLND results. CONCLUSIONS: Identifying patients with residual lymph node basin disease remains difficult. Thus, lymph node dissection should be performed in all patients after positive sentinel node biopsy.