Treatment of Patients with Melanoma of the Extremity Using Hyperthermic Isolated Limb Perfusion with Melphalan, Tumor Necrosis Factor, and Interferon Gamma: Results of a Tumor Necrosis Factor Dose-Escalation Study

Purpose: To evaluate response rates and systemic and regional toxicity of hyperthermic isolated limb perfusion (ILP) for treatment of in-transit metastases of extremity melanoma using escalating-dose tumor necrosis factor (TNF) in conjunction with melphalan and interferon gamma (IFN). Patients and Methods: All patients received IFN 0.2 mg² for 2 days followed by a 90-minute ILP with TNF and IFN (0.2 mg) given at time 0 and melphalan (10 mg/ L limb volume) given at 30 minutes. Twenty-six patients were treated with 4 mg of TNF and 12 patients received 6 mg of TNF. All patients had assessable disease in the perfusion field and all but two patients were assessable for response at 1 month after treatment. Results: Mean peak perfusate TNF levels in the 4-mg group were 4.8 μg/mL, compared with 7.4 μg/mL for the 6-mg group (P = .03). The complete response rate in the 4-mg TNF group was 76%, with an overall objective response rate of 92%, compared with 36% and 100% for the 6-mg group. Subgroup analyses showed that the lower complete response rate in the 6-mg TNF group was not explained by differences in disease burden or prior regional therapy. Systemic drug toxicity was short-lived, easily managed, and related to perfusate leak more than to TNF perfusate dose. Regional toxicity, particularly painful myopathy and neuropathy, was greater with the 6-mg dose level and was considered dose-limiting. Conclusion: ILP with 4 mg TNF, IFN, and melphalan can lead to complete local responses in the majority of patients with extremity melanoma. Escalating the TNF dose to 6 mg did not increase the complete response rate and increased regional toxicity.