Management of Bilateral Wilms Tumours

ABSTRACT

Synchronous bilateral Wilms tumours (BWTs) represent 4% to 7% of all Wilms tumours (WTs) and present at a younger age than unilateral WTs do. At least 10% of synchronous BWTs have unfavourable histology, and up to 22% are associated with genitourinary abnormalities, aniridia, WAGR (WT, aniridia, genitourinary anomalies, and retardation) syndrome, Denys–Drash syndrome, hemihypertrophy or one of the other overgrowth syndromes. The long-term disease-free survival rate of patients with unilateral WT is now approaching 90% and is around 70% for those with metastatic disease. For both synchro¬nous and metachronous WTs, the prognosis is less favourable, with reported cure rates approaching 80% in the best centres but are often considerably less in resource-poor settings. Also, there is the potential for a reduced quality of life due to renal insufficiency and the possible need for renal transplantation. Thus, the major clinical challenge in BWTs is the preservation of functioning renal tissue, while achieving cure with the minimum of therapy-related morbidity. Although mortality is generally associated with progressive disease of anaplastic tumours, the emphasis of management has been increasingly placed on nephron-sparing surgical approaches in an attempt to reduce ultimate renal insufficiency. Chemo-therapy followed by nephron-sparing surgery has been able, in most cases, to eradicate the tumour while preserving renal function. Radiotherapy has largely been avoided because of fear of long-term radiation injury to the residual functioning renal mass. Patient selection, appropriate pre- and post-operative chemotherapy, and skilful surgical techniques all contribute to excellent outcomes, where these are achievable.