Pulmonary metastasectomy for malignant melanoma: prognostic factors for long-term survival.

More than 80% of patients with metastatic melanoma initially show only one distant organ site involvement, most commonly the lungs. Several studies on patients with pulmonary metastatic diseases have determined prognostic factors for survival; however, these studies included patients with a variety of primary tumor types and failed to discriminate melanoma-specific prognostic factors. Surgical therapy has been shown in several studies to be associated with a 5-year survival rate as high as 39%. We retrospectively analyzed 48 patients with previously treated melanoma who developed pulmonary metastases and were admitted between 1990 and 2006. The overall survival was estimated using Kaplan-Meier analysis. Log-rank and Breslow's tests were used to compare survival differences for each variable. Multivariate analyses to determine the independent prognostic factors for overall survival were performed using the Cox proportional hazard model, as identified by the univariate analyses. The median overall survival for all patients was 32 months, with an estimated 5-year survival rate of 36%. Multivariate analyses identified the type of resection and the number of malignant nodules resected as independent prognostic factors for overall survival. We observed a significant survival benefit from pulmonary metastasectomy for a subset of patients with metastatic pulmonary melanoma.