A Southwest Oncology Group phase II Trial of recombinant tumor necrosis factor in metastatic breast cancer.

New approaches are needed in the treatment of advanced breast cancer. In vitro studies have shown that recombinant tumor necrosis factor (TNF) is a growth inhibitor for the MCF-7, ZR-75-1, and BT-20 human breast cancer cell lines. Based on these considerations, the Southwest Oncology Group performed a Phase II trial of recombinant TNF (Genentech) (150 micrograms/m2) given by 30-minute intravenous infusion on days 1 to 5 of every other week for 8 weeks. Patients with metastatic breast cancer who had received one prior chemotherapy regimen for advanced disease were eligible. Of the 22 patients who were entered, 3 were ineligible. Nineteen patients who had a performance status of 2 or less could be examined (median age, 53 years). One possible fatal toxic reaction has been seen in a patient who had intracranial bleeding caused by a previously undiagnosed brain metastasis; no other treatment-related deaths have occurred. Toxicity has included nausea, vomiting, fever, chills, myalgia, and fatigue. No Grade 4 toxicity has been observed. Grade 3 toxic reactions have included hypotension (two patients), diarrhea (one patient), transient leukopenia (two patients), and reversible elevations of liver function test values (two patients). No objective responses have been observed. Twelve of 19 patients have died (median survival time, 8.5 months). Recombinant TNF is inactive as a single agent in patients with previously treated metastatic breast cancer.