Renin in Wilms' tumor: prorenin as an indicator.

In a prospective study, 25 children with nephroblastoma (Wilms' tumor) had preoperative plasma prorenin and renin concentrations measured. The mean plasma renin and prorenin concentrations in the patients were raised compared with a control group of patients without nephroblastoma. Four children had recurrence of tumor and, in three, this was associated with an increase in plasma prorenin concentration. Nephroblastoma tissue contained immunoreactive renin and renin messenger RNA, and the renin protein was immunologically and biochemically similar to normal human renin. We conclude that prorenin concentrations in plasma are an indicator of nephroblastoma.