[Clinical study of prophylactic therapy of interferon on postoperative renal cell carcinoma]

A clinical trial using interferon alpha 2b (IFN alpha-2b) for prophylactic therapy was done on 44 patients who had received nephrectomy for renal cell carcinoma. Principally, the daily intramuscular injection of 3 of 6 million units of IFN alpha-2b was done for 4 consecutive weeks after 2 weeks postoperatively and thereafter followed by injection once every 2 weeks. The clinical evaluation was done for the recurrence rate, the survival rate, the IFN alpha and IFN gamma producing ability, the activity of 2',5' oligoadenylate synthetase (2-5AS) and the side effect. Out of 44 cases entered, 42 were completely evaluable and recurrence was observed in 5 (11.9%) of the 42 cases. The recurrence rate was 5.5% and 16.4%, at the first and second year, respectively. Three (7.1%) of the 42 patients died. The survival rate was 97.6% at the first year, 89.7% at the second year for the followup study. The IFN alpha producing capacity was low in all of the 4 evaluable cases. The IFN gamma producing capacity was high in 3 cases and normal in 1 case. 2-5AS, the enzyme produced by IFN, was activated by IFN alpha-2b administration in all of the 4 evaluable cases. Side effects were observed in 24 (54.5%) of the 44 cases. The main side effect was fever. Leucopenia, general fatigue, appetite loss, temporary elevation of liver transaminase were also observed. However, there were only 5 cases (11.4%) in which administration of IFN alpha-2b had to be discontinued.