Background: Anecdotal reports of melanoma recurrence 15 years after complete lymphadenectomy have led to claims that the onset of nodal metastasis invariably signals systemic metastases and a terminal diagnosis. Few series in the literature are able to refute this assertion. We therefore examined rates of long-term (> 15-25 years) survival for patients with regional (nodal) melanoma.
Patients and methods: We performed an analysis of patients with American Joint Committee on Cancer stage III melanoma entered into a prospective database for the last 30 years. All patients were seen at the treating institution within 4 months of their diagnosis and monitored thereafter. All patients underwent complete lymphadenectomy. Patients receiving melanoma vaccines were excluded. Statistical comparisons used Chi-square analysis and the log-rank test.
Results: At a maximum follow up of 386 months (32 years) for the population of 1422 patients, rates of 15-, 20-, and 25-year melanoma-specific survival were 36% +/- 1%, 35% +/- 1%, and 35% +/- 1%, respectively. When patients were stratified by clinical status of regional lymph nodes, survival rates were significantly lower (P = 0.001) if nodes were palpable. The number of tumor-positive nodes (P < 0.0001), the pathological primary tumor stage (P = 0.005), age (P = 0.0001), and gender (P = 0.002) also were significantly related to long-term survival.
Discussion: Long-term survivors of melanoma metastatic to regional lymph nodes are not uncommon, and the extremely low rate of recurrence beyond 15 years suggests that this disease-free interval is usually synonymous with cure. Although some risk factors decrease the likelihood of long-term survival, the high overall rates of extended survival in all risk groups clearly support surgical management as the primary treatment for regional metastatic melanoma.