[Renal function and size after complex treatment of Wilms' tumour]

The aim of our study was to measure renal function and growth in survivors of unilateral Wilms' tumour in 21 children and young adults (7 female). The mean age was 12.6 +/- 4.8 years, mean follow-up time was 7.01 +/- 4.25 years: seven of the group received irradiation (35 Gy). Blood pressure was normal in all patients. Three of them had elevated cystatin C and clearance of cystatin C below referenced normal value. The others had normal renal function tests (cystatin C, creatinine and cystatin clearance, B2 microglobulin, microalbuminuria, osmolality). Compared to the control we found higher cystatin C values in children treated before the age 3 years old (p=0.03) and in children treated more than 5 years before (p=0.03), and lower cystatin clearance in group treated before the age 3 years old (p=0,03). No difference between the irradiated and non-irradiated group was found. We observed a greater increase in volume (155.9% +/- 33.4) than in length (127.9% +/- 6.3). The highest rise of renal volume was in children treated more than 5 years before (174.6% +/- 22.3). In conclusion, our data suggest that after combined treatment for Wilms' tumour compensatory renal hypertrophy and a tendency progressive renal dysfunction takes place.