Objectives: Study of the antitumour effects of erythropoietin on metastatic renal cell carcinoma.
Methods: After giving their informed consent, 20 patients with histologically proven metastatic renal cell carcinoma received subcutaneous recombinant erythropoietin three times a day at a dose of 150 IU/kg when haemoglobin was less than or equal to 12 g/dL or 75 IU/kg when haemoglobin was higher than 12 g/dL. Treatment was continued for a minimum of 8 weeks before reassessment and was continued thereafter, except in the case of progression or excessive toxicity. A staging assessment was performed every 8 weeks and the response was assessed on the basis of WHO criteria. A clinical and laboratory assessment was performed every two months to evaluate toxicity, graded according to the WHO scale. All but one of the patients had received immunotherapy or chemotherapy prior to inclusion in the study.
Results: One complete response (> 12 months), one partial response (8 months), two minor responses, 10 cases of stabilisation and 6 cases of progression were observed. 15 patients received treatment at full doses. In 5 patients, the duration of treatment was reduced before the 8 weeks initially defined because of tumour progression in one patient and because of haemoglobin persistently greater than 15 g/dL in 4 other patients. Adverse effects consisted of 1 case of moderate headache, 2 cases of transient bone pain, and 1 case of transient hypertension.
Conclusion: Erythropoietin exerts a moderate antitumour effect which needs to be confirmed by a phase II trial of first-line treatment in selected patients.