Combined treatment with low-dose interferon plus vinblastine is associatedwith less toxicity than conventional interferon monotherapy in patients with metastatic renal cell carcinoma

The outcome of treatment of advanced renal cell carcinoma is disappointing. In interferon (IFN)-treated patients, the high incidence of adverse effect s causes many patients to withdraw from treatment. This 12-week randomized study compared the incidence of toxicity associated with high-dose IFN mono therapy (15 X 10(6) U thrice weekly) and treatment with the combination of low-dose IFN (5 X 10(6) U thrice meekly) and 6 mg/m(2) vinblastine (VBL) ev ery 14 days in 100 consecutive patients. There was no significant differenc e in response rate between treatment arms (42% IFN vs. 34% IFN + VBL) or be tween subgroups (by tumor location), Combined treatment was associated with a significantly lower incidence of fever, fatigue, and weight loss but wit h a higher incidence of leukopenia. There was no significant difference in the incidence of other events. More patients treated with IFN monotherapy r equired bed rest, and overall treatment costs were 60% higher than for comb ined treatment. It is concluded that combined treatment with low-dose IFN a nd VBL, without loss of short-term efficacy, is better tolerated and less e xpensive than high-dose IFN monotherapy.