Paul R. Bowlin

A Comprehensive Review of Pediatric Urachal Anomalies and Predictive Analysis for Adult Urachal Adenocarcinoma

PURPOSEnWe examined the presentation, diagnosis and management of radiologically detected pediatric urachal anomalies and assessed the risk of malignant degeneration.nnnMATERIALS AND METHODSnOur radiology database (2000 to 2012) was queried for all children younger than 18 years who were diagnosed with a urachal anomaly radiographically, and the operative database was used to determine those who underwent excision. Data collected included demographics, presenting symptoms, imaging modality and indication for excision. These data were compared to the Ontario Cancer Registry to determine the risk of malignancy.nnnRESULTSnA total of 721 patients were radiographically diagnosed with a urachal anomaly (667 incidentally), yielding a prevalence of 1.03% of the general pediatric population. Diagnoses were urachal remnants (89% of cases), urachal cysts (9%) and patent urachus (1.5%). Ultrasonography was the most common imaging modality (92% of cases), followed by fluoroscopy/voiding cystourethrography (5%) and computerized tomography/magnetic resonance imaging (3%). A total of 61 patients (8.3%) underwent surgical excision. Indications for imaging and treatment were umbilical drainage (43% of patients), abdominal pain (28%), palpable mass (25%) and urinary tract infection (7%). Mean age at excision was 5.6 years and 64% of the patients were male. Based on provincial data, the number needed to be excised to prevent a single case of urachal adenocarcinoma was 5,721.nnnCONCLUSIONSnUrachal anomalies are more common than previously reported. Children with asymptomatic lesions do not appear to benefit from prophylactic excision, as the risk of malignancy later in life is remote and a large number of urachal anomalies would need to be removed to prevent a single case of urachal adenocarcinoma.

Innovations in the management of Wilms' tumor.

Advances in the management of Wilms’ tumor have been dramatic over the past half century, not in small part due to the institution of multimodal therapy and the formation of collaborative study groups. While different opinions exist in the management of Wilms’ tumors depending on where one lives and practices, survival rates have surpassed 90% across the board in Western societies. With more children surviving into adulthood, the concerns about morbidity have reached the forefront and now represent as much a consideration as oncologic outcomes these days. Innovations in treatment are on the horizon in the form of potential tumor markers, molecular biological means of testing for chemotherapeutic responsiveness, and advances in the delivery of chemotherapy for recurrent or recalcitrant tumors. Other technological innovations are being applied to childhood renal tumors, such as minimally invasive and nephron-sparing approaches. Risk stratification also allows for children to forego potentially unnecessary treatments and their associated morbidities. Wilms’ tumor stands as a great example of the gains that can be made through protocol-driven therapy with strenuous outcomes analyses. These gains continue to spark interest in minimization of morbidity, while avoiding any compromise in oncologic efficacy. While excitement and innovation are important in the advancement of treatment delivery, we must continue to temper this enthusiasm and carefully evaluate options in order to continue to provide the highest standard of care in the management of this now highly curable disease.

Laparoscopic Nephrectomy and Partial Nephrectomy: Intraperitoneal, Retroperitoneal, Single Site

The indication for use of laparoscopy, in the pediatric population, was initially for diagnostic purposes. As confidence with the technology and utility grew, it began to be applied for therapeutic indications. With equivalent surgical outcomes and decreased morbidity, the usefulness of a laparoscopic approach became more apparent, and today minimally invasive surgery is an indispensable tool in the management of many pediatric urologic conditions. The management of renal pathologies using laparoscopy is now currently the approach of choice for most pediatric renal maladies.

Contemporary Practice Patterns of Voiding Cystourethrography Use at a Large Tertiary Care Center in a Single Payer Health Care System

Purpose: Voiding cystourethrogram involves radiation exposure and is invasive. Several guidelines, including the 2011 AAP (American Academy of Pediatrics) guidelines, no longer recommend routine voiding cystourethrogram after the initial urinary tract infection in children. The recent trend in voiding cystourethrogram use remains largely unknown. We examined practice patterns of voiding cystourethrogram use and explored the impact of these guidelines in a single payer system in the past 8 years. Materials and Methods: We identified all voiding cystourethrograms performed at a large pediatric referral center between January 2008 and December 2015. Patients 2 to 24 months old who underwent an initial voiding cystourethrogram for the diagnosis of a urinary tract infection in the first 6 months of 2009 and 2014 were identified. Medical records were retrospectively reviewed. Results: During the study period 8,422 voiding cystourethrograms were performed and the annual number declined over time. In the pre‐AAP and post‐AAP cohorts 233 and 95 initial voiding cystourethrograms were performed, respectively. While there was no statistically significant difference in the vesicoureteral reflux detection rate between 2009 and 2014 (37.3% vs 43.0%, p = 0.45), there was a threefold increase in high grade vesicoureteral reflux in 2014 (2.6% vs 8.4%, p = 0.03). Conclusions: A clear trend toward fewer voiding cystourethrograms was noted at our institution. This decrease started before 2011 and cannot be attributed to the AAP guidelines alone. While most detected vesicoureteral reflux remains low grade, there was a greater detection rate of high grade vesicoureteral reflux in 2014 compared to 2009. This may reflect a favorable impact of a more selective approach to obtaining voiding cystourethrograms.

Side-to-Side Refluxing Nondismembered Ureterocystotomy: A Novel Strategy to Address Obstructed Megaureters in Children

Purpose: A nonrefluxing megaureter is a relatively common cause of antenatal hydronephrosis. Although nonoperative management is favored, surgical intervention is sometimes warranted. However, there is controversy regarding the best approach, particularly in young children. We describe our experience with nondismembered side‐to‐side refluxing ureterocystotomy as a simple option to address obstruction. Materials and Methods: Between January 2012 and January 2017, 32 patients underwent ureterocystotomy at 4 referral centers in North America. Demographics, surgical indications, complications, need for further interventions and change in hydronephrosis were captured. Patients were monitored clinically and with serial ultrasounds. Results: Mean age at surgery was 3.7 months (range 0 to 33) and 25 (78%) patients were male. Unilateral procedures were performed in 29 patients. All patients were initially identified based on the presence of antenatal hydronephrosis and symptoms developed in 10. The procedure was conducted for primary nonrefluxing megaureter in 27 patients and to address secondary obstruction in the remainder. Mean followup was 34.3 months (range 6 to 58). At the most recent evaluation most children demonstrated significant improvement in dilation (86%). To date, 6 patients have undergone further procedures, including a circumcision and 2 ureteral reimplantations for recurrent infections. Conclusions: Our results suggest that side‐to‐side refluxing ureterocystotomy is a straightforward, minimally invasive alternative for the surgical management of nonrefluxing megaureter. Despite the trade‐off of relieving obstruction and creating reflux, it can be considered a potentially definitive procedure in patients who remain infection‐free, particularly circumcised boys. Extended followup with close monitoring is critical to document long‐term results with this intervention.

Novel Strategy for Temporary Decompression of the Lower Urinary Tract in Neonates Using a Ureteral Stent

PURPOSEnIn children with congenital obstructive uropathy, including posterior urethral valves, lower urinary tract decompression is recommended pending definitive surgical intervention. Current options, which are limited to a feeding tube or Foley catheter, pose unappreciated constraints in luminal diameter and are associated with potential problems. We assess the impact of luminal diameter on the current draining options and present a novel alternative method, repurposing a widely available stent that optimizes drainage.nnnMATERIALS AND METHODSnWe retrospectively reviewed patients diagnosed with posterior urethral valves between January 2013 and December 2014. In all patients a 6Fr 12 cm Double-J ureteral stent was advanced over a guidewire in a retrograde fashion into the bladder. Luminal flow and cross-sectional areas were also assessed for each of 3 tubes for urinary drainage, ie 6Fr Double-J stent, 5Fr feeding tube and 6Fr Foley catheter.nnnRESULTSnA total of 30 patients underwent uneventful bedside Double-J stent placement. Mean ± SD age at valve ablation was 28.5 ± 16.6 days. Mean ± SD peak serum creatinine was 2.23 ± 0.97 mg/dl after birth and 0.56 ± 0.22 mg/dl at the procedure. Urine output after stent placement was excellent in all patients. The Foley catheter and feeding tube drained approximately 18 and 6 times more slowly, respectively, and exhibited half the calculated cross-sectional luminal area compared to the Double-J stent.nnnCONCLUSIONSnUse of Double-J stents in neonates with posterior urethral valves is a safe and effective alternative method for lower urinary tract decompression that optimizes the flow/lumen relationship compared to conventional drainage options.