Overall Survival and Renal Function of Patients With Synchronous Bilateral Wilms Tumor Undergoing Surgery at a Single Institution

Abstract

Objectives Wilms tumor (WT) is the most common renal cancer in children. Approximately 5% of children with WT present with disease in both kidneys. The treatment challenge is to achieve a high cure rate while maintaining long-term renal function. We retrospectively reviewed our institutional experience with nephron-sparing surgery (NSS) in patients with synchronous bilateral Wilms tumor (BWT) operated on between 2001-2014. Methods Imaging studies, surgical approach, adjuvant therapy and pathology reports were reviewed. Outcomes evaluated included surgical complications, tumor recurrence, patient survival and renal function, as assessed by estimated glomerular filtration rate (eGFR). Results Forty-two patients with BWT were identified. Thirty-nine (92.9%) patients underwent bilateral NSS; only three patients (7.1%) underwent unilateral nephrectomy with contralateral NSS. Post-operative complications included prolonged urine leak (10), infection (6), intussusception (2) and transient renal insufficiency (1). Three patients required early (within four months) repeat NSS for residual tumor. Long-term, seven (16.7%) patients had local tumor recurrence (managed with repeat NSS in 6 and completion nephrectomy in 1) and three had an episode of intestinal obstruction requiring surgical intervention. Overall survival was 85.7% (mean follow-up, 4.1 years). Of the 6 patients who died, 5 had diffuse anaplastic histology. All patients had an eGFR>60mL/min/1.73m2 at last follow-up; no patient developed end-stage renal disease. Conclusions In patients with synchronous, bilateral Wilms tumor, bilateral nephron-sparing surgery is safe and almost always feasible, there by preserving maximal renal parenchyma. With this approach, survival was excellent, as was maintenance of renal function.

Comprehensive renal function evaluation in patients treated for synchronous bilateral Wilms tumor

“…It is possible that patients who undergo bilateral NSS conserve more nephron mass despite requiring adjuvant therapy for positive margins, resulting in better renal function with time. Importantly, this approach does not appear to be associated with worse oncologic outcomes [18]. Thus, in patients with bilateral Wilms tumor, a full comprehensive renal function analysis will help to identify patients with mild renal dysfunction, not suspected based on equations estimating GFR and dipstick urinalysis.…”

“…This surgical approach is particularly relevant as these patients may be exposed to nephrotoxic chemotherapeutic agents and/or direct renal radiation to treat positive margins and/or diffuse anaplasia [11-16]. Giel and colleagues previously reported the results of renal function evaluation in a small series of patients with BWT [17] and we recently reported the oncologic outcomes of a larger cohort of patients [18]. We undertook the present study to evaluate renal function in BWT patients after NSS, with the specific goal of comparing the calculation of GFR using technetium renal clearance studies to a comprehensive panel of renal function tests, urine chemistry studies, and different equations to estimate GFR…”

Wilms tumor: “State-of-the-art” update, 2016

“…It is important to note that the tumor compresses normal renal parenchyma and that radiographic tumor characteristics may underestimate the proportion of BWT that are amenable to NSS. 55 MRI has become more widely used in cases of BWT especially in those with predisposition syndromes such as WAGR/BWS. The children with inherently abnormal kidney architecture are predisposed to nephrogenic rests and thus WT.…”

Renal Function of Patients With Synchronous Bilateral Wilms Tumor

“…W e read with great interest the important paper recently published by Davidoff et al 1 in Annals of Surgery. The authors reviewed their institutional experience with nephron-sparing surgery in 42 children with synchronous bilateral Wilms tumor.…”