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Journal of Pediatric Urology (2014) xx, 1e6
Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm R. Li, M. Lightfoot, M. Alsyouf, L. Nicolay, D.D. Baldwin, D.A. Chamberlin* Department of Urology, Loma Linda University Medical Center, Loma Linda, CA 92354, USA Received 19 March 2014; accepted 6 August 2014
KEYWORDS Ureteral polyps; Ureteropelvic junction obstruction; Pyeloplasty; Ureteroscopy
Abstract Objective: The present study reports experience with the diagnosis and treatment of fibroepithelial polyps of the upper urinary tract in the pediatric population. Incorporating past experience from literature, an algorithm to guide clinical diagnosis and treatment plans is proposed. Material and methods: Four pediatric patients undergoing pyeloplasty for ureteropelvic junction obstruction (UPJ) obstruction were diagnosed with ureteral polyps. Their demographics, radiologic, surgical and pathologic information were reviewed. In addition, a comprehensive literature search using the MEDLINE database yielded 37 reports containing 126 cases of ureteral polyps, including 5 series with 57 cases, and 9 cases of synchronous bilateral ureteral polyps. Results: Of the 123 pediatric patients undergoing pyeloplasty from 2008 to 2013, four (3.3%) were found to have fibroepithelial polyps of the upper urinary tract. All patients were male and the mean age of presentation was 12 years. Ureteral polyps predominantly occurred unilaterally in the left ureter (75.0%) and one case of bilateral ureteral polyps was encountered. Along with three other recent case series [1e3], the combined incidence of ureteral polyps in patients undergoing evaluation for ureteral obstruction was 5.2%. Intraoperative retrograde pyelogram was used to identify filling defects in four of the five affected ureters. Ureterorenoscopy was performed in all three patients with filling defects, for polyp mapping along the ureter and evaluation of the macroscopic polyp appearance. Based on ureteroscopic findings, Holmium laser polypectomy was performed in two patients with single, pedunculated polyps. Anderson-Hynes dismembered pyeloplasty was performed in three patients with broadbased, multilobulated polyps that were too large for endoscopic treatment, and in one patient for undiagnosed polyp prior to pyeloplasty.
* Corresponding author. Department of Urology, Loma Linda University School of Medicine, 11234 Anderson Street, Room A560, Loma Linda, CA 92354, USA. Tel.: þ1 909 558 4196; fax: þ1 909 558 4806. E-mail addresses: [email protected] (R. Li), [email protected] (M. Lightfoot), [email protected] (M. Alsyouf), [email protected] (L. Nicolay), [email protected] (D.D. Baldwin), [email protected] (D.A. Chamberlin). http://dx.doi.org/10.1016/j.jpurol.2014.08.004 1477-5131/ª 2014 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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R. Li et al. Conclusion: Ureteral polyps cause approximately 5.0% of UPJ obstruction in the pediatric population. Diagnosis can be made in certain cases by intraoperative retrograde pyelogram. If a filling defect is encountered, ureteroscopy is indicated for polyp mapping. The treatment modality is dictated by the endoscopic appearance of the ureteral polyp. ª 2014 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.
Introduction Fibroepithelial polyps are benign mesenchymal tumors that can arise anywhere along the urinary tract. Previously, the incidence of fibroepithelial polyps in the upper urinary tract was thought to be exceedingly low, consisting of only 0.5% of all causes of UPJ obstruction in the pediatric population [4]. The occurrence of synchronous, bilateral ureteral polyps is even scarcer, with only nine reports in the English literature [3e9]. Different phenotypes of fibroepithelial polyps have been noted: some are long, cylindrical masses, whilst others are shorter, wider and more likely to cause urinary obstruction [5]. Clinically, this entity mimics the symptoms of intrinsic UPJ obstruction and is often undiagnosed until the time of pyeloplasty. With the advent of ureteroscopy in the pediatric population, more recent reports of endoscopic diagnosis and treatment of ureteral polyps have appeared. However, the role of endoscopy to complement open repair has not been clearly defined. The present study reports experience with the diagnosis and treatment of fibroepithelial polyps of the upper urinary tract in the pediatric population. Along with information gathered from a comprehensive literature review, an algorithm has been constructed in an attempt to help guide treatment plans.
Material and methods After approval by the Institutional Review Board, a retrospective chart review of 123 pediatric patients (0e17 years) undergoing pyeloplasty between August 2008 and December 2013 at a single academic children’s hospital was conducted. Four cases of UPJ obstruction associated with ureteral polyps were identified. Patient demographics as
Table 1
well as clinical, diagnostic, intraoperative, pathologic and follow-up data were reviewed. In addition, a comprehensive MEDLINE literature search yielded 37 reports containing 126 cases of ureteral polyps in the pediatric literature, including five case series representing 45.0% of the reported cases (see Table 1). The reported incidence, patient demographics, diagnostic, treatment and follow-up data in all reports were reviewed.
Results At the present hospital, between August 2008 and December 2013, a total of 123 pediatric pyeloplasties were performed by two surgeons (DDB and DAC). Among them, four patients (3.3%) with ureteral polyps were identified. All patients were male and their ages ranged from 8 to 16 years (mean 12 years). The ureteral polyps occurred in the left ureter in three out of the four patients (75.0%) and were bilateral in one patient (25.0%). All four patients presented with flank pain, and associated nausea and vomiting. All patients were initially evaluated with renal ultrasound, which showed hydronephrosis on the symptomatic side, but failed to identify the ureteral polyps. Urinalysis showed microscopic hematuria in two patients and pyuria in another. Urine cultures were negative in all patients. All patients underwent diuretic MAG3 renogram, which demonstrated unequivocal mechanical obstruction in three of the five affected ureters (T1/2 > 20 min); equivocal obstruction in another (T1/2 Z 14 min); and no obstruction in the last ureter (T1/2 Z 8 min). Ipsilateral renal function ranged from 45.0% to 58.0% in the three patients with unilateral ureteral polyps. In the patient with bilateral ureteral polyps, split renal function was 51.7% on the right (T1/2 Z 14 min) and 48.3% on the left (T1/2 > 25 min).
Case series of pediatric ureteral fibroepithelial polyps. Number of Incidence Number of Detection Endoscopic Pyeloplasty Follow-up Incidence of patients bilateral polyps using treatment length recurrence urography (month)
Adey et al. (2003) Niu et al. (2007) Kara et al. (2010) Kojima et al. (2011) Bian et al. (2011) Current Total a
9 15 5 14 13 4 60
0.5% 4.6% 5.9% 7.0% n/a 3.3% 5.2%
2 1 0 0 2 1 6
28.5% 26.7% 0.0% 21.4% 100.0% 75.0% 43.1%
0 0 100.0% 100.0% 0.0% 50.0% 35.0%
100.0% 100.0% 0 100.0% 100.0% 100.0% 91.7%
48 n/a 12 >12 16 10 e
0 n/a 0 9a 0 0 9
9 total recurrences in six patients.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Diagnosis and management of ureteral fibroepithelial polyps in children Intraoperative retrograde pyelogram identified filling defects in four of the five affected ureters (80.0%), including both ureters in the patient with bilateral ureteral polyps. All three patients with filling defects underwent ureterorenoscopy for polyp mapping. Additionally, endoscopic holmium laser polypectomy was performed in two of the three patients. All patients eventually underwent pyeloplasty. The patient with bilateral, giant filliform ureteral polyps emanating from the UPJs was deemed unsuitable for endoscopic treatment. He underwent staged bilateral Anderson-Hynes dismembered pyeloplasty to completely excise the ureteral polyps en bloc with the diseased UPJs. Dismembered pyeloplasty was performed in the other patients after ureterorenoscopy, as significant polyposis was found at the UPJ. In the patient without a filling defect on the retrograde pyelogram, a single cylindrical polyp was discovered and removed en bloc at the time of pyeloplasty. All pyeloplasties were performed open, and ureteral stents were routinely left postoperatively according to the surgeon’s preference. Grossly, the ureteral polyps of all unilaterally affected patients appeared to be slender, cylindrically shaped polypoid masses (Fig. 1A); whilst in the bilaterally affected patient, multilobulated polyps emanated from a broad base on the UPJ (Fig. 1B). Histologic review showed reactive urothelial mucosa surrounding a fibromuscular stalk in all cases, which was consistent with ureteral polyps. Average length of hospital stay was 2.4 days and no perioperative complications were encountered. Length of follow-up ranged from 6 to 18 months (mean 10 months). At the last follow-up, all patients remained asymptomatic. Renal ultrasound obtained 2e3 months postoperatively showed improvement of hydronephrosis. One patient also underwent diuretic renogram, which showed improved drainage (T1/2 Z 3.5 min vs. 8 min) and renal function (55.0% vs. 50.0%). The MEDLINE search yielded a total of 36 articles containing 91 cases of ureteral polyps encountered in the pediatric population. Another report of 35 cases focused on the ultrasonic detection of ureteral polyps rather than their clinical diagnosis and treatment [10]. The mean age of presentation was 8.8 years, 92.0% (106/115) of the patients were males and 67.0% (53/79 cases) of the ureteral polyps occurred in the left ureter. Of the 126 patients, nine had
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bilateral ureteral polyps (Table 2). A total of 62.0% (41/66) ureters contained multiple synchronous fibroepithelial polyps. Clinical presentation most commonly consisted of ipsilateral flank pain (54/71 cases, 76.0%) and microscopic hematuria (14/71, 19.7%). Other rare, but significant, presenting symptoms included: pyuria (one case), UTI (two cases), flank mass at birth (one case) and hydronephrosis (one case). Excretory, retrograde or magnetic resonance urographies were performed in 119 cases, of which 58 (49.0%) were positive for filling defects. The primary modality of treatment was: nephroureterectomy in four [11e14]; ureterectomy and reanastomosis in five [5,8,15e17]; open, laparoscopic or robotic-assisted pyeloplasty in 111; and ureteroscopy with endoscopic treatment in six patients [1,18]. Reoperation was performed in 13 patients; the indications for reoperations were the discovery of contralateral ureteral polyps in three [5,6,9], persistent obstruction in three [4,15,19], ureteral stricture in one [18] and recurrent ureteral polyps in six patients [2].
Discussion Fibroepithelial polyps are a relatively rare cause of UPJ obstruction in the pediatric population. Previously, their incidence was reported to be as low as 0.5% in all children undergoing pyeloplasty [4]. However, the combined incidence in the present series, along with three other recent reports, was 38/796 (5.2%) in pediatric patients undergoing evaluation for clinical ureteral obstruction (Table 1). It is unclear whether this represents an increasing incidence of ureteral fibroepithelial polyps, improved detection or documentation, or publication bias. Interestingly, there is a predilection for males (92.0%) and the left ureter (67.0%). Little is known about the etiology of ureteral polyps. Although they are generally thought to be a congenital condition, no specific cause of ureteral polyps has been established. Various hypotheses have been proposed, including: chronic irritation, infection, obstruction, trauma, and hormonal and developmental disturbances [20]. Advances in embryology and molecular biology may provide better understanding in the future.
Figure 1 A) Slender, cylindrically shaped, pedunculated ureteral polyps. B) Multilobulated, filliform polyps emanating from broad base on the UPJ.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Case reports of bilateral ureteral polyps.
Bartone et al. (1990) Lavelle et al. (1997) Bhalla et al. (2002) Adey et al. (2003) Niu et al. (2007) Romesburg et al. (2009) Bian et al. (2011) Current
Age (years)
Gender
Presenting symptoms
Radiographic findings
Number of surgeries
12 8 11 4 5 9 7 n/a n/a 8
M M M M M M M n/a n/a M
Renal colic Renal colic Renal colic Abdominal pain Abdominal pain Flank pain Left abdominal pain Abdominal pain Abdominal pain Bilateral renal colic
Bilateral obstruction on renogram Bilateral hydroureteronephrosis Bilateral hydronephrosis n/a n/a Hydronephrosis Left hydronephrosis Bilateral hydronephrosis Bilateral hydronephrosis Bilateral hydronephrosis
2 1 2 n/a n/a n/a 2 1 1 2
Diagnosis of ureteral fibroepithelial polyps is challenging due to their clinical and radiographic similarity to intrinsic UPJ obstruction. Excretory, retrograde and, more recently, magnetic resonance urography have been utilized to detect ureteral polyps. Overall, filling defects were detected in 49.0% of the 119 cases. In the study by Adey et al., the preoperative detection rate was 2/7 (28.5%) [4]. In three more-recent case series, the incidence of filling defects detection varied between 0.0% and 27.0% (Table 1) for excretory urography and 21.0% for magnetic resonance urography. On retrograde pyelogram, polyps were identified in 13/29 ureters. In addition, in the present study, filling defects in three out of four ureteral polyp patients were detected by performing retrograde pyelogram intraoperatively. Although the routine use of retrograde pyelogram prior to dismembered pyeloplasty has been controversial, given the significant incidence of ureteral polyps, the retrograde pyelogram serves as an essential part of the diagnostic evaluation prior to surgery. In addition, performing retrograde pyelogram can identify other pathologies such as ureteral strictures, ureterovesical junction obstruction, and adynamic ureteral segments. In one recent study, results of the retrograde pyelogram led to modification of the surgical approach for UPJ obstruction in 18.9% of patients [21]. If bilateral renal colic or hydronephrosis is present, bilateral retrograde pyelogram is warranted to rule out ureteral polyps. Of the 10 cases of bilateral ureteral polyps reported, all but one patient had bilateral renal colic, bilateral hydronephrosis or both on initial presentation (Table 2). The diagnosis of bilateral ureteral polyps in the initial surgical setting can potentially save the patient additional diagnostic radiographic exams, surgical procedures and emotional distress upon onset of contralateral symptoms. Albeit a subtle finding, the detection of filling defects indicative of ureteral polyps mandates endoscopic evaluation of the entire ureter to rule out distal ureteral polyps, as cases of multiple synchronous ureteral polyps are common [2,6,11,13e15,19,22,23]. In addition, the macroscopic appearance of the ureteral polyp can be appreciated by endoscopic examination. Polyps that are pedunculated and solitary can be effectively treated endoscopically using a Holmium:YAG laser [2,6,18]. Kara et al. reported successful ureteroscopic treatment of polyps in five children aged 4e9
years (average 6.4 years) using a 9.6 Fr ureteroscope. Balloon dilation of the ureteral orifice was required in two children. No intraoperative or long-term complications were noted [1]. Similarly, Bhalla et al. described successful ureteroscopic Holmium laser treatment of ureteral polyps without complications in an 11-year-old boy [6]. However, multiple recurrences of ureteral polyps were reported in another study. Kojima et al. described antegrade ureteroscopy through the laparoscopic ports in the setting of laparoscopic pyeloplasty [2]. In all, nine recurrences were noted in six patients, with one patient having three recurrences leading to four total endoscopic procedures. Although the holmium laser was employed for polypectomy, thorough ablation of the polyp bases was not reported. Moreover, performing ureteroscopy through the laparoscopic ports after incising the UPJ may impair the quality of the endoscopic treatment, leading to incompletely treated polyps and recurrence. In the present series, single modality ureteroscopic treatment was attempted for the first patient, but it was complicated by the excessive number of polyps emanating from the UPJ, leading to incomplete treatment. This patient eventually underwent dismembered pyeloplasty to excise the UPJ en bloc with several proximal ureteral polyps. In the second patient, both antegrade and retrograde ureteroscopy were used in conjunction with dismembered pyeloplasty to effectively treat several distal ureteral polyps. In the patient with bilateral disease, ureteroscopy was used for diagnosis; however, due to the multilobulated appearance with broad polyp base, bilateral dismembered pyeloplasties were performed. When performing ureteroscopy in the pediatric population, gentle handling of the ureteroscope within the urinary tract is required to prevent ureteral injury and stricture formation. Childs et al. reported symptomatic ureteral strictures requiring open pyeloplasty in two adults and one pediatric patient who had been treated endoscopically. For the pediatric patient, a 6F semi-rigid ureteroscope was used along with cautery fulguration on multiple polyps at the UPJ [18]. Similarly, Romesburg et al. reported a 7-yearold boy who required pyeloplasty for recurrent UPJ obstruction after laser polypectomy and endopyelotomy in the same setting [9]. Similar to the patient in the present series with bilateral ureteral polyps, multiple polyps were seen emanating from the UPJ in both patients who
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Diagnosis and management of ureteral fibroepithelial polyps in children
Figure 2
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Algorithm for diagnosis and treatment of ureteral polyps in children.
eventually underwent pyeloplasty. A possible explanation for the ineffectiveness of endoscopic treatment in these patients may stem from the coexistence of ureteral polyps with intrinsic UPJ obstruction. Furthermore, Bartone et al. speculated that removal of only the pedunculated portion of the polyp may leave an obstructing base, leading to recurrence of UPJ obstruction [5]. Another obstacle encountered on occasion are large ureteral polyps occupying the entire ureteral lumen, making endoscopic resection impossible [24]. When large, multilobulated, broad-based ureteral polyps are encountered at the UPJ, dismembered pyeloplasty may be the best treatment option. An interesting strategy to incorporate ureteroscopic guidance by illuminating the base of the polyp may be used to facilitate identifying the incisional site during laparoscopic or open pyeloplasty [24]. If ureteral polyps are encountered during pyeloplasty, it is important to perform ureteroscopy to identify additional distal ureteral polyps and perform polypectomy using the Ho:YAG laser. Fig. 2 shows the therapeutic algorithm summarizing the above treatment strategies. Two cases of ureteral polyps in infants aged 6 weeks [4] and 2 months [3] have been reported. These patients presented with an abdominal mass at birth or hydronephrosis on prenatal ultrasound. In all cases reviewed, no incidence of renal function impairment due to ureteral fibroepithelial polyps was reported. In addition, as endoscopic management may be difficult in infants, the option of proceeding straight to pyeloplasty in small children in whom endoscopy may not be safely performed is reasonable. If persistent hydronephrosis is encountered on follow-up imaging after pyeloplasty and distal ureteral polyps are suspected, one option would be to perform retrograde pyelography and ureteroscopy when these procedures can be safely performed based on the child’s size. Some weaknesses exist in the present study. Being a rare disease, the clinical experience with ureteral polyps needs
to be compared with those previously reported in literature. The quality of published reports varied, and only five case series were identified in the English literature. Among these, reporting of the relevant clinical, diagnostic and therapeutic information was inconsistent, making comparisons difficult. Due to the rarity of encountering ureteral polyps, a large enough patient population has not yet been accumulated to conduct a prospective study in order to validate the constructed therapeutic algorithm. Such a study may require multi-institutional collaboration in the future.
Conclusion Ureteral polyps cause approximately 5.0% of cases of UPJ obstruction in the pediatric population. Diagnosis remains elusive, but can be made in certain cases by retrograde pyelogram performed prior to pyeloplasty procedures. Bilateral retrograde pyelograms are indicated if a patient presents with bilateral flank pain or hydronephrosis. If a filling defect is encountered on the retrograde pyelogram, ureteroscopy is indicated for polyp mapping. Single, pedunculated polyps can be effectively treated endoscopically with holmium laser ablation, whilst large, multilobulated, broad-based polyps occurring at the UPJ should be treated with dismembered pyeloplasty.
Conflict of interest statement No competing financial interests exist.
Funding source None declared.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Acknowledgment The authors would like to acknowledge the Department of Pathology at Loma Linda University Medical Center for pathologic analysis of surgical specimens.
[11] [12] [13]
References [1] Kara C, Resorlu B, Oguz U, Unsal A. Incidentally detected ureteral fibroepithelial polyps in children: is endoscopic treatment of them really necessary? Int Urol Nephrol 2010;42:1e5. [2] Kojima Y, Lambert SM, Steixner BL, Laryngakis N, Casale P. Multiple metachronous fibroepithelial polyps in children. J Urol 2011;185:1053e7. [3] Niu ZB, Yang Y, Hou Y, Chen H, Wang CL. Ureteral polyps: an etiological factor of hydronephrosis in children that should not be ignored. Pediatr Surg Int 2007;23:323e6. [4] Adey GS, Vargas SO, Retik AB, Borer JG, Mandell J, Hendren WH, et al. Fibroepithelial polyps causing ureteropelvic junction obstruction in children. J Urol 2003;169:1834e6. [5] Bartone FF, Johansson SL, Markin RJ, Imray TJ. Bilateral fibroepithelial polyps of ureter in a child. Urology 1990;35: 519e22. [6] Bhalla RS, Schulsinger DA, Wasnick RJ. Treatment of bilateral fibroepithelial polyps in a child. J Endourol Endourol Soc 2002; 16:581e2. [7] Bian Z, Liu X, Hua Y, Liu F, Lin T, He D. Laparoscopic management of multiple ureteral polyps in children. J Urol 2011; 186:1444e9. [8] Lavelle JP, Knisely AS, Bellinger MF. Benign fibroepithelial polyps causing symptomatic bilateral intermittent hydroureteronephrosis. J Urol 1997;158:569. [9] Romesburg JW, Stein RJ, Desai MM, Lagwinski N, Ross JH. Treatment of child with bilateral ureteropelvic junction obstruction due to fibroepithelial polyps and review of the literature. Urology 2009;73(929):e9e11. [10] Wang XM, Jia LQ, Wang Y, Wang N. Utilizing ultrasonography in the diagnosis of pediatric fibroepithelial polyps causing
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ureteropelvic junction obstruction. Pediatr Radiol 2012;42: 1107e11. Evans AT, Stevens RK. Fibroepithelial polyps of ureter and renal pelvis: a case report. J Urol 1961;86:313e5. Gup A. Benign mesodermal polyp in childhood. J Urol 1975; 114:619e20. Abrams HJ, Buchbinder MI, Sutton AP. Benign ureteral lesions: rare causes of hydronephrosis in children. Urology 1977;9: 517e20. Eilenberg J, Seery W, Cole A. Multiple fibroepithelial polyps in the pediatric age group: case report. J Urol 1977;117:793. Compere DE, Begley GF, Isaacks HE, Frazier TH, Dryden CB. Ureteral polyps. J Urol 1958;79:209e14. Musselman P, Kay R. The spectrum of urinary tract fibroepithelial polyps in children. J Urol 1986;136:476e7. Liddell RM, Weinberger E, Schofield DE, Pelman RS. Fibroepithelial polyp of the ureter in a child. AJR Am J Roentgenol 1991;157:1273e4. Childs MA, Umbreit EC, Krambeck AE, Sebo TJ, Patterson DE, Gettman MT. Fibroepithelial polyps of the ureter: a singleinstitutional experience. J Endourol Endourol Soc 2009;23: 1415e9. Ruiz-Lopez MJ, Ramirez-Garrido F, Nogueras-Ocana M, MunozHoyos A, Martin A. Recurrent ureteric fibroepithelial polyp in a child. Eur J Pediatr 2004;163:124e5. Cassar Delia E, Joseph VT, Sherwood W. Fibroepithelial polyps causing ureteropelvic junction obstruction in childrenea case report and review article. Eur J Pediatr Surg 2007;17:142e6. Narayanan SK, Smith G, Thomas G, Cohen RC. Does the surgical approach change the need for a retrograde pyelogram prior to pyeloplasty? J Pediatr Urol 2014. Pub Med ID: 24690464. Berger RM, Lebowitz JM, Carroll PA. Ureteral polyps presenting as ureteropelvic junction obstruction in children. J Urol 1982;128:805e7. Crum PM, Sayegh ES, Sacher EC, Wescott JW. Benign ureteral polyps. J Urol 1969;102:678e82. Radojicic Z, Basta-Jovanovic G, Dimitrijevic I, RadojevicSkodric S, Arsic D, Kalezic N, et al. Fibroepithelial polyp of the upper third of ureter. ANZ J Surg 2008;78:718.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Journal of Pediatric Urology (2014) xx, 1e6
Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm R. Li, M. Lightfoot, M. Alsyouf, L. Nicolay, D.D. Baldwin, D.A. Chamberlin* Department of Urology, Loma Linda University Medical Center, Loma Linda, CA 92354, USA Received 19 March 2014; accepted 6 August 2014
KEYWORDS Ureteral polyps; Ureteropelvic junction obstruction; Pyeloplasty; Ureteroscopy
Abstract Objective: The present study reports experience with the diagnosis and treatment of fibroepithelial polyps of the upper urinary tract in the pediatric population. Incorporating past experience from literature, an algorithm to guide clinical diagnosis and treatment plans is proposed. Material and methods: Four pediatric patients undergoing pyeloplasty for ureteropelvic junction obstruction (UPJ) obstruction were diagnosed with ureteral polyps. Their demographics, radiologic, surgical and pathologic information were reviewed. In addition, a comprehensive literature search using the MEDLINE database yielded 37 reports containing 126 cases of ureteral polyps, including 5 series with 57 cases, and 9 cases of synchronous bilateral ureteral polyps. Results: Of the 123 pediatric patients undergoing pyeloplasty from 2008 to 2013, four (3.3%) were found to have fibroepithelial polyps of the upper urinary tract. All patients were male and the mean age of presentation was 12 years. Ureteral polyps predominantly occurred unilaterally in the left ureter (75.0%) and one case of bilateral ureteral polyps was encountered. Along with three other recent case series [1e3], the combined incidence of ureteral polyps in patients undergoing evaluation for ureteral obstruction was 5.2%. Intraoperative retrograde pyelogram was used to identify filling defects in four of the five affected ureters. Ureterorenoscopy was performed in all three patients with filling defects, for polyp mapping along the ureter and evaluation of the macroscopic polyp appearance. Based on ureteroscopic findings, Holmium laser polypectomy was performed in two patients with single, pedunculated polyps. Anderson-Hynes dismembered pyeloplasty was performed in three patients with broadbased, multilobulated polyps that were too large for endoscopic treatment, and in one patient for undiagnosed polyp prior to pyeloplasty.
* Corresponding author. Department of Urology, Loma Linda University School of Medicine, 11234 Anderson Street, Room A560, Loma Linda, CA 92354, USA. Tel.: þ1 909 558 4196; fax: þ1 909 558 4806. E-mail addresses: [email protected] (R. Li), [email protected] (M. Lightfoot), [email protected] (M. Alsyouf), [email protected] (L. Nicolay), [email protected] (D.D. Baldwin), [email protected] (D.A. Chamberlin). http://dx.doi.org/10.1016/j.jpurol.2014.08.004 1477-5131/ª 2014 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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R. Li et al. Conclusion: Ureteral polyps cause approximately 5.0% of UPJ obstruction in the pediatric population. Diagnosis can be made in certain cases by intraoperative retrograde pyelogram. If a filling defect is encountered, ureteroscopy is indicated for polyp mapping. The treatment modality is dictated by the endoscopic appearance of the ureteral polyp. ª 2014 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.
Introduction Fibroepithelial polyps are benign mesenchymal tumors that can arise anywhere along the urinary tract. Previously, the incidence of fibroepithelial polyps in the upper urinary tract was thought to be exceedingly low, consisting of only 0.5% of all causes of UPJ obstruction in the pediatric population [4]. The occurrence of synchronous, bilateral ureteral polyps is even scarcer, with only nine reports in the English literature [3e9]. Different phenotypes of fibroepithelial polyps have been noted: some are long, cylindrical masses, whilst others are shorter, wider and more likely to cause urinary obstruction [5]. Clinically, this entity mimics the symptoms of intrinsic UPJ obstruction and is often undiagnosed until the time of pyeloplasty. With the advent of ureteroscopy in the pediatric population, more recent reports of endoscopic diagnosis and treatment of ureteral polyps have appeared. However, the role of endoscopy to complement open repair has not been clearly defined. The present study reports experience with the diagnosis and treatment of fibroepithelial polyps of the upper urinary tract in the pediatric population. Along with information gathered from a comprehensive literature review, an algorithm has been constructed in an attempt to help guide treatment plans.
Material and methods After approval by the Institutional Review Board, a retrospective chart review of 123 pediatric patients (0e17 years) undergoing pyeloplasty between August 2008 and December 2013 at a single academic children’s hospital was conducted. Four cases of UPJ obstruction associated with ureteral polyps were identified. Patient demographics as
Table 1
well as clinical, diagnostic, intraoperative, pathologic and follow-up data were reviewed. In addition, a comprehensive MEDLINE literature search yielded 37 reports containing 126 cases of ureteral polyps in the pediatric literature, including five case series representing 45.0% of the reported cases (see Table 1). The reported incidence, patient demographics, diagnostic, treatment and follow-up data in all reports were reviewed.
Results At the present hospital, between August 2008 and December 2013, a total of 123 pediatric pyeloplasties were performed by two surgeons (DDB and DAC). Among them, four patients (3.3%) with ureteral polyps were identified. All patients were male and their ages ranged from 8 to 16 years (mean 12 years). The ureteral polyps occurred in the left ureter in three out of the four patients (75.0%) and were bilateral in one patient (25.0%). All four patients presented with flank pain, and associated nausea and vomiting. All patients were initially evaluated with renal ultrasound, which showed hydronephrosis on the symptomatic side, but failed to identify the ureteral polyps. Urinalysis showed microscopic hematuria in two patients and pyuria in another. Urine cultures were negative in all patients. All patients underwent diuretic MAG3 renogram, which demonstrated unequivocal mechanical obstruction in three of the five affected ureters (T1/2 > 20 min); equivocal obstruction in another (T1/2 Z 14 min); and no obstruction in the last ureter (T1/2 Z 8 min). Ipsilateral renal function ranged from 45.0% to 58.0% in the three patients with unilateral ureteral polyps. In the patient with bilateral ureteral polyps, split renal function was 51.7% on the right (T1/2 Z 14 min) and 48.3% on the left (T1/2 > 25 min).
Case series of pediatric ureteral fibroepithelial polyps. Number of Incidence Number of Detection Endoscopic Pyeloplasty Follow-up Incidence of patients bilateral polyps using treatment length recurrence urography (month)
Adey et al. (2003) Niu et al. (2007) Kara et al. (2010) Kojima et al. (2011) Bian et al. (2011) Current Total a
9 15 5 14 13 4 60
0.5% 4.6% 5.9% 7.0% n/a 3.3% 5.2%
2 1 0 0 2 1 6
28.5% 26.7% 0.0% 21.4% 100.0% 75.0% 43.1%
0 0 100.0% 100.0% 0.0% 50.0% 35.0%
100.0% 100.0% 0 100.0% 100.0% 100.0% 91.7%
48 n/a 12 >12 16 10 e
0 n/a 0 9a 0 0 9
9 total recurrences in six patients.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Diagnosis and management of ureteral fibroepithelial polyps in children Intraoperative retrograde pyelogram identified filling defects in four of the five affected ureters (80.0%), including both ureters in the patient with bilateral ureteral polyps. All three patients with filling defects underwent ureterorenoscopy for polyp mapping. Additionally, endoscopic holmium laser polypectomy was performed in two of the three patients. All patients eventually underwent pyeloplasty. The patient with bilateral, giant filliform ureteral polyps emanating from the UPJs was deemed unsuitable for endoscopic treatment. He underwent staged bilateral Anderson-Hynes dismembered pyeloplasty to completely excise the ureteral polyps en bloc with the diseased UPJs. Dismembered pyeloplasty was performed in the other patients after ureterorenoscopy, as significant polyposis was found at the UPJ. In the patient without a filling defect on the retrograde pyelogram, a single cylindrical polyp was discovered and removed en bloc at the time of pyeloplasty. All pyeloplasties were performed open, and ureteral stents were routinely left postoperatively according to the surgeon’s preference. Grossly, the ureteral polyps of all unilaterally affected patients appeared to be slender, cylindrically shaped polypoid masses (Fig. 1A); whilst in the bilaterally affected patient, multilobulated polyps emanated from a broad base on the UPJ (Fig. 1B). Histologic review showed reactive urothelial mucosa surrounding a fibromuscular stalk in all cases, which was consistent with ureteral polyps. Average length of hospital stay was 2.4 days and no perioperative complications were encountered. Length of follow-up ranged from 6 to 18 months (mean 10 months). At the last follow-up, all patients remained asymptomatic. Renal ultrasound obtained 2e3 months postoperatively showed improvement of hydronephrosis. One patient also underwent diuretic renogram, which showed improved drainage (T1/2 Z 3.5 min vs. 8 min) and renal function (55.0% vs. 50.0%). The MEDLINE search yielded a total of 36 articles containing 91 cases of ureteral polyps encountered in the pediatric population. Another report of 35 cases focused on the ultrasonic detection of ureteral polyps rather than their clinical diagnosis and treatment [10]. The mean age of presentation was 8.8 years, 92.0% (106/115) of the patients were males and 67.0% (53/79 cases) of the ureteral polyps occurred in the left ureter. Of the 126 patients, nine had
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bilateral ureteral polyps (Table 2). A total of 62.0% (41/66) ureters contained multiple synchronous fibroepithelial polyps. Clinical presentation most commonly consisted of ipsilateral flank pain (54/71 cases, 76.0%) and microscopic hematuria (14/71, 19.7%). Other rare, but significant, presenting symptoms included: pyuria (one case), UTI (two cases), flank mass at birth (one case) and hydronephrosis (one case). Excretory, retrograde or magnetic resonance urographies were performed in 119 cases, of which 58 (49.0%) were positive for filling defects. The primary modality of treatment was: nephroureterectomy in four [11e14]; ureterectomy and reanastomosis in five [5,8,15e17]; open, laparoscopic or robotic-assisted pyeloplasty in 111; and ureteroscopy with endoscopic treatment in six patients [1,18]. Reoperation was performed in 13 patients; the indications for reoperations were the discovery of contralateral ureteral polyps in three [5,6,9], persistent obstruction in three [4,15,19], ureteral stricture in one [18] and recurrent ureteral polyps in six patients [2].
Discussion Fibroepithelial polyps are a relatively rare cause of UPJ obstruction in the pediatric population. Previously, their incidence was reported to be as low as 0.5% in all children undergoing pyeloplasty [4]. However, the combined incidence in the present series, along with three other recent reports, was 38/796 (5.2%) in pediatric patients undergoing evaluation for clinical ureteral obstruction (Table 1). It is unclear whether this represents an increasing incidence of ureteral fibroepithelial polyps, improved detection or documentation, or publication bias. Interestingly, there is a predilection for males (92.0%) and the left ureter (67.0%). Little is known about the etiology of ureteral polyps. Although they are generally thought to be a congenital condition, no specific cause of ureteral polyps has been established. Various hypotheses have been proposed, including: chronic irritation, infection, obstruction, trauma, and hormonal and developmental disturbances [20]. Advances in embryology and molecular biology may provide better understanding in the future.
Figure 1 A) Slender, cylindrically shaped, pedunculated ureteral polyps. B) Multilobulated, filliform polyps emanating from broad base on the UPJ.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Case reports of bilateral ureteral polyps.
Bartone et al. (1990) Lavelle et al. (1997) Bhalla et al. (2002) Adey et al. (2003) Niu et al. (2007) Romesburg et al. (2009) Bian et al. (2011) Current
Age (years)
Gender
Presenting symptoms
Radiographic findings
Number of surgeries
12 8 11 4 5 9 7 n/a n/a 8
M M M M M M M n/a n/a M
Renal colic Renal colic Renal colic Abdominal pain Abdominal pain Flank pain Left abdominal pain Abdominal pain Abdominal pain Bilateral renal colic
Bilateral obstruction on renogram Bilateral hydroureteronephrosis Bilateral hydronephrosis n/a n/a Hydronephrosis Left hydronephrosis Bilateral hydronephrosis Bilateral hydronephrosis Bilateral hydronephrosis
2 1 2 n/a n/a n/a 2 1 1 2
Diagnosis of ureteral fibroepithelial polyps is challenging due to their clinical and radiographic similarity to intrinsic UPJ obstruction. Excretory, retrograde and, more recently, magnetic resonance urography have been utilized to detect ureteral polyps. Overall, filling defects were detected in 49.0% of the 119 cases. In the study by Adey et al., the preoperative detection rate was 2/7 (28.5%) [4]. In three more-recent case series, the incidence of filling defects detection varied between 0.0% and 27.0% (Table 1) for excretory urography and 21.0% for magnetic resonance urography. On retrograde pyelogram, polyps were identified in 13/29 ureters. In addition, in the present study, filling defects in three out of four ureteral polyp patients were detected by performing retrograde pyelogram intraoperatively. Although the routine use of retrograde pyelogram prior to dismembered pyeloplasty has been controversial, given the significant incidence of ureteral polyps, the retrograde pyelogram serves as an essential part of the diagnostic evaluation prior to surgery. In addition, performing retrograde pyelogram can identify other pathologies such as ureteral strictures, ureterovesical junction obstruction, and adynamic ureteral segments. In one recent study, results of the retrograde pyelogram led to modification of the surgical approach for UPJ obstruction in 18.9% of patients [21]. If bilateral renal colic or hydronephrosis is present, bilateral retrograde pyelogram is warranted to rule out ureteral polyps. Of the 10 cases of bilateral ureteral polyps reported, all but one patient had bilateral renal colic, bilateral hydronephrosis or both on initial presentation (Table 2). The diagnosis of bilateral ureteral polyps in the initial surgical setting can potentially save the patient additional diagnostic radiographic exams, surgical procedures and emotional distress upon onset of contralateral symptoms. Albeit a subtle finding, the detection of filling defects indicative of ureteral polyps mandates endoscopic evaluation of the entire ureter to rule out distal ureteral polyps, as cases of multiple synchronous ureteral polyps are common [2,6,11,13e15,19,22,23]. In addition, the macroscopic appearance of the ureteral polyp can be appreciated by endoscopic examination. Polyps that are pedunculated and solitary can be effectively treated endoscopically using a Holmium:YAG laser [2,6,18]. Kara et al. reported successful ureteroscopic treatment of polyps in five children aged 4e9
years (average 6.4 years) using a 9.6 Fr ureteroscope. Balloon dilation of the ureteral orifice was required in two children. No intraoperative or long-term complications were noted [1]. Similarly, Bhalla et al. described successful ureteroscopic Holmium laser treatment of ureteral polyps without complications in an 11-year-old boy [6]. However, multiple recurrences of ureteral polyps were reported in another study. Kojima et al. described antegrade ureteroscopy through the laparoscopic ports in the setting of laparoscopic pyeloplasty [2]. In all, nine recurrences were noted in six patients, with one patient having three recurrences leading to four total endoscopic procedures. Although the holmium laser was employed for polypectomy, thorough ablation of the polyp bases was not reported. Moreover, performing ureteroscopy through the laparoscopic ports after incising the UPJ may impair the quality of the endoscopic treatment, leading to incompletely treated polyps and recurrence. In the present series, single modality ureteroscopic treatment was attempted for the first patient, but it was complicated by the excessive number of polyps emanating from the UPJ, leading to incomplete treatment. This patient eventually underwent dismembered pyeloplasty to excise the UPJ en bloc with several proximal ureteral polyps. In the second patient, both antegrade and retrograde ureteroscopy were used in conjunction with dismembered pyeloplasty to effectively treat several distal ureteral polyps. In the patient with bilateral disease, ureteroscopy was used for diagnosis; however, due to the multilobulated appearance with broad polyp base, bilateral dismembered pyeloplasties were performed. When performing ureteroscopy in the pediatric population, gentle handling of the ureteroscope within the urinary tract is required to prevent ureteral injury and stricture formation. Childs et al. reported symptomatic ureteral strictures requiring open pyeloplasty in two adults and one pediatric patient who had been treated endoscopically. For the pediatric patient, a 6F semi-rigid ureteroscope was used along with cautery fulguration on multiple polyps at the UPJ [18]. Similarly, Romesburg et al. reported a 7-yearold boy who required pyeloplasty for recurrent UPJ obstruction after laser polypectomy and endopyelotomy in the same setting [9]. Similar to the patient in the present series with bilateral ureteral polyps, multiple polyps were seen emanating from the UPJ in both patients who
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Diagnosis and management of ureteral fibroepithelial polyps in children
Figure 2
5
Algorithm for diagnosis and treatment of ureteral polyps in children.
eventually underwent pyeloplasty. A possible explanation for the ineffectiveness of endoscopic treatment in these patients may stem from the coexistence of ureteral polyps with intrinsic UPJ obstruction. Furthermore, Bartone et al. speculated that removal of only the pedunculated portion of the polyp may leave an obstructing base, leading to recurrence of UPJ obstruction [5]. Another obstacle encountered on occasion are large ureteral polyps occupying the entire ureteral lumen, making endoscopic resection impossible [24]. When large, multilobulated, broad-based ureteral polyps are encountered at the UPJ, dismembered pyeloplasty may be the best treatment option. An interesting strategy to incorporate ureteroscopic guidance by illuminating the base of the polyp may be used to facilitate identifying the incisional site during laparoscopic or open pyeloplasty [24]. If ureteral polyps are encountered during pyeloplasty, it is important to perform ureteroscopy to identify additional distal ureteral polyps and perform polypectomy using the Ho:YAG laser. Fig. 2 shows the therapeutic algorithm summarizing the above treatment strategies. Two cases of ureteral polyps in infants aged 6 weeks [4] and 2 months [3] have been reported. These patients presented with an abdominal mass at birth or hydronephrosis on prenatal ultrasound. In all cases reviewed, no incidence of renal function impairment due to ureteral fibroepithelial polyps was reported. In addition, as endoscopic management may be difficult in infants, the option of proceeding straight to pyeloplasty in small children in whom endoscopy may not be safely performed is reasonable. If persistent hydronephrosis is encountered on follow-up imaging after pyeloplasty and distal ureteral polyps are suspected, one option would be to perform retrograde pyelography and ureteroscopy when these procedures can be safely performed based on the child’s size. Some weaknesses exist in the present study. Being a rare disease, the clinical experience with ureteral polyps needs
to be compared with those previously reported in literature. The quality of published reports varied, and only five case series were identified in the English literature. Among these, reporting of the relevant clinical, diagnostic and therapeutic information was inconsistent, making comparisons difficult. Due to the rarity of encountering ureteral polyps, a large enough patient population has not yet been accumulated to conduct a prospective study in order to validate the constructed therapeutic algorithm. Such a study may require multi-institutional collaboration in the future.
Conclusion Ureteral polyps cause approximately 5.0% of cases of UPJ obstruction in the pediatric population. Diagnosis remains elusive, but can be made in certain cases by retrograde pyelogram performed prior to pyeloplasty procedures. Bilateral retrograde pyelograms are indicated if a patient presents with bilateral flank pain or hydronephrosis. If a filling defect is encountered on the retrograde pyelogram, ureteroscopy is indicated for polyp mapping. Single, pedunculated polyps can be effectively treated endoscopically with holmium laser ablation, whilst large, multilobulated, broad-based polyps occurring at the UPJ should be treated with dismembered pyeloplasty.
Conflict of interest statement No competing financial interests exist.
Funding source None declared.
Please cite this article in press as: Li R, et al., Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm, Journal of Pediatric Urology (2014), http://dx.doi.org/10.1016/j.jpurol.2014.08.004
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Acknowledgment The authors would like to acknowledge the Department of Pathology at Loma Linda University Medical Center for pathologic analysis of surgical specimens.
[11] [12] [13]
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