BACKGROUND: Interleukin-2 (IL-2) recently was approved by the Food and Drug Administration for the treatment of renal cell cancer. It is effective in a small minority of patients, but no markers identify individuals likely to respond to treatment. METHODS: Two polycythemic patients with erythropoietin-producing renal cell cancer and three other polycythemic patients with renal cell cancer were treated with the combination of IL-2 and alpha-interferon (alpha-IFN). RESULTS: All five patients achieved a partial or complete remission. In both patients in which it was measured, the erythropoietin level decreased significantly with treatment, and the polycythemia resolved in all patients. Hypothyroidism developed in two patients, and transient hyperthyroidism developed in another. CONCLUSION: These results contrast with those achieved with IL-2 alone or in combination with lymphokine-activated killer cells, for which a 15% response rate was seen in patients with renal cell cancer and polycythemia. Although less than 5% of renal cell tumors produce erythropoietin, its production may identify a subset of individuals with renal cell cancer responsive to IL-2 and alpha-IFN.
BACKGROUND:Interleukin-2 (IL-2) recently was approved by the Food and Drug Administration for the treatment of renal cell cancer. It is effective in a small minority of patients, but no markers identify individuals likely to respond to treatment. METHODS: Two polycythemic patients with erythropoietin-producing renal cell cancer and three other polycythemic patients with renal cell cancer were treated with the combination of IL-2 and alpha-interferon (alpha-IFN). RESULTS: All five patients achieved a partial or complete remission. In both patients in which it was measured, the erythropoietin level decreased significantly with treatment, and the polycythemia resolved in all patients. Hypothyroidism developed in two patients, and transient hyperthyroidism developed in another. CONCLUSION: These results contrast with those achieved with IL-2 alone or in combination with lymphokine-activated killer cells, for which a 15% response rate was seen in patients with renal cell cancer and polycythemia. Although less than 5% of renal cell tumors produce erythropoietin, its production may identify a subset of individuals with renal cell cancer responsive to IL-2 and alpha-IFN.