Bilateral wilms' tumour: a ten year experience in two academic centers in Johannesburg

Abstract

Background: Nephroblastoma is the commonest genitourinary malignancy affecting 1 in 10,000 children worldwide. Five to 10% present bilaterally. Method:Retrospective record review of nephroblastomas at Chris Hani Baragwanath and Charlotte Maxeke Academic Hospitals from 1 January 2003 to 31 December 2013. Results: Eighteen patients (7.70%) presented with bilateral disease, they presented at a younger age than those with unilateral disease. Three patients presented with metachronous disease (tumour to contralateral kidney) at median age of 23 months, initial tumour presentation was at median of 2 months, the remaining 14 with synchronous disease at a median age of 27 months. Treatment followed aspects of the SIOP 9 protocol. Two patients died prior to surgery. Thirteen kidneys were removed in entirety. Twelve patients had nephron sparing surgery with 6 microscopically positive resection margins. Two patients with residual microscopic disease relapsed. Three kidneys demonstrated unfavourable histology. Nephroblastomatosis was identified in one kidney. Eight patients are alive and disease free and three patients are alive with disease. This cohort of patients have an overall and disease-free survival of 66.67% and 55.56%. Neither age above 2 years nor metachronous disease was associated with a poorer prognosis. Conclusion: Bilateral nephroblastoma is a complex disease. The majority of patients presented with advanced local disease. Relapse was more commonly influenced by the presence of microscopically positive margins than metastatic disease at presentation