Prognostic factors in metastatic melanoma patients treated with biochemotherapy and maintenance immunotherapy

Abstract

Background: With no U.S. Food and Drug Administration-approved standard therapy other than high-dose interleukin-2 and dacarbazine for metastatic melanoma, biochemotherapy has shown promise, with long-term survival in selected patients. We felt that the study of prognostic factors would determine which patients might benefit from this intensive therapy.

Methods: One hundred thirty-five consecutive patients with metastatic melanoma treated with decrescendo biochemotherapy followed by maintenance immunotherapy over 5 years were retrospectively studied to determine the most important prognostic factors for both overall survival and progression-free survival.

Results: The median overall survival (OS) time was 16.6 months, with 1-year and 5-year survival rates of 70% and 28%, respectively. The median progression-free survival (PFS) time was 7.6 months, with 15% of patients progression free at 5 years. PFS curves showed no relapses after 30 months, so remissions were durable. For OS, a performance status score of zero, normal lactate dehydrogenase (LDH) level, stage M1a, and nonvisceral sites of metastasis were favorable factors. The group with normal LDH levels and skin or nodes as one of their metastatic sites had a relatively good prognosis, with median survival time of 44 months and an estimated 5-year survival rate of 38%. Conversely, patients with an elevated LDH level without any skin or nodal metastases had a poor prognosis, with no long-term survivors.

Conclusions: Metastatic melanoma patients treated with biochemotherapy and maintenance immunotherapy who have either a normal LDH level or skin or nodes as one of their metastatic sites may have durable remissions of their disease, and this therapy should be studied further in these groups.