Locoregional cutaneous metastasis in patients with therapeutic lymph node dissection for malignant melanoma: risk factors and prognostic impact

In patients with lymph node metastasis of malignant melanoma, the incidence of additional locoregional cutaneous metastases has not been well documented. More importantly, the prognostic impact of locoregional cutaneous metastases appearing prior to therapeutic lymphadenectomy is unclear. Using Kaplan-Meier estimations and a Cox proportional hazards model, we addressed these questions in 224 patients with palpable lymph node metastases to the axilla or the groin. The 10 year overall probability to develop regional cutaneous metastasis, calculated from primary tumour excision, was 38.7%. Using univariate and multivariate analysis, Breslow thickness was a significant risk factor of in-transit disease in node-positive patients. In 24 patients (10.7%) locoregional cutaneous metastases had appeared before therapeutic lymphadenectomy, but this was not associated with a survival disadvantage. In conclusion, locoregional cutaneous metastases amenable to surgical excision do not significantly influence the survival prognosis after therapeutic lymphadenectomy. In the subpopulation of patients with lymph node metastasis, Breslow thickness predicts the probability of additional locoregional cutaneous metastasis. (C) 2002 Lippincott Williams Wilkins.