Is cerebral palsy associated with successful ureteral access during the initial attempt at ureteroscopy for urolithiasis in children and young adults?

BACKGROUND: Ureteroscopy is a common treatment for urolithiasis, but initial ureteral access is not always possible, particularly in pediatrics. Clinical experience suggests that neuromuscular conditions such as cerebral palsy (CP) may facilitate access, thus avoiding the need for pre-stenting and staged procedures. OBJECTIVE: We sought to determine if probability of successful ureteral access (SUA) during initial attempted ureteroscopy (IAU) is higher in pediatric patients with CP vs. without CP. STUDY DESIGN: We reviewed IAU cases for urolithiasis (2010-2021) at our center. Patients with pre-stenting, prior ureteroscopy, or urologic surgical history were excluded. CP was defined using ICD-10 codes. SUA was defined as scope access to urinary tract level sufficient to reach stone. Association of CP and other factors with SUA were evaluated. RESULTS: 230 patients (45.7% male, median age: 16 years [IQR: 12-18 y], 8.7% had CP) underwent IAU, with SUA in 183 (79.6%). SUA occurred in 90.0% of patients with CP vs. 78.6% of those without CP (p = 0.38). SUA was 81.7% in patients >12 years (vs. 73.8% in those <12), and the highest SUA was in those >12 years with CP (93.3%), but these differences were not statistically significant. Renal stone location was significantly associated with lower SUA (p = 0.007). Among patients with renal stone only, SUA in those with CP was 85.7% vs. 68.9% in those without CP (p = 0.33). SUA did not differ significantly by gender or BMI. CONCLUSIONS: CP may facilitate ureteral access during IAU in pediatric patients, but we were unable to show a statistically significant difference. Further study of larger cohorts may demonstrate whether CP or other patient factors are associated with successful initial access. Improved understanding of such factors would help preoperative counseling and surgical planning for children with urolithiasis.

Interdisciplinary Collaboration in a Pediatric Urology Outpatient Clinic at a Tertiary Children's Hospital: A Case Series.

OBJECTIVE: To increase awareness and understanding of how psychology, social work, and child life specialties can integrate into interdisciplinary pediatric urology care. To advocate for increased access to psychology, social work, and child life specialty care in other pediatric urology care centers. METHODS: Authors participated in a series of discussion groups to develop the aim and goals for this study and identify patients that would best exemplify the interdisciplinary nature of care provided. Initially, fifteen patients were selected; further focused discussion groups supported the selection of 6 patients that are described in this study. RESULTS: Authors present a series of 6 case studies aimed to illustrate the interdisciplinary support available to pediatric urology patients in 1 tertiary care center. Cases review a range of presenting issues, including a patient learning clean intermittent catheterization (CIC), a patient resistant to surgical intervention, patients with bowel and bladder dysfunction, a patient undergoing voiding cystourethrogram (VCUG), and a patient with urinary frequency, all of whom presented with a range of psychosocial needs that impacted their urological treatment. CONCLUSION: Access to a psychosocial support staff can improve adherence to medical treatment by reducing barriers to care and promoting behavioral change, support patients in coping and reducing post-traumatic stress following surgery and invasive procedures, improve communication between patients, families, and medical staff, and treat psychological issues that contribute to urinary symptoms. Additional literature exploring how these interventions reduce costs associated with medical intervention, hospitalizations, outpatient visits, emergency visits, and sedation for procedures would be beneficial.

Comparing Pediatric Ureteroscopy Outcomes with SuperPulsed Thulium Fiber Laser and Low-Power Holmium:YAG Laser.

PURPOSE: The thulium fiber laser is a promising new lithoptripsy technology never before studied in the pediatric population. Our center adopted the first platform in North America, the SuperPulsed thulium fiber laser (SPTF). We aimed to compare outcomes in pediatric ureteroscopy using the SPTF to those using the gold standard, low-power holmium:yttrium-aluminum-garnet (Ho:YAG) laser. MATERIALS AND METHODS: This is a retrospective, consecutive cohort study of unilateral ureteroscopy with laser lithotripsy performed in pediatric patients from 2016 to 2021 as an early adopter of the SPTF. Thirty-day complications and stone-free status, defined as the absence of a stone fragment on followup imaging within 90 days, were analyzed using logistic regression. Operative times were compared using linear regression. Propensity scores for use of SPTF were used in regression analyses to account for potential cohort imbalance. RESULTS: A total of 125 cases were performed in 109 pediatric patients: 93 with Ho:YAG and 32 with SPTF. No significant difference was noted in age (p=0.2), gender (p=0.6), stone burden (p >0.9) or stone location (p=0.1). The overall stone-free rate was 62%; 70% with SPTF and 59% with Ho:YAG. The odds of having a residual stone fragment were significantly lower with SPTF than with Ho:YAG (OR=0.39, 95% CI: 0.19-0.77, p=0.01). There was no significant difference in operative time (p=0.8). Seven (25%) complications were noted with SPTF and 19 (22%) with Ho:YAG (p=0.6). CONCLUSIONS: The SPTF laser was associated with a higher stone-free rate than the low-power Ho:YAG laser without compromising operative time and safety.

Flat Panel Detector c-Arms Are Associated with Dramatically Reduced Radiation Exposure During Ureteroscopy and Produce Superior Images.

Background: We wished to determine whether newly available flat panel detector (FPD) c-arms were (1) associated with lower radiation dose during ureteroscopy (URS) than conventional image intensifier (CII) c-arms and (2) to compare fluoroscopic image quality between the units. Materials and Methods: We retrospectively reviewed 44 consecutive patients undergoing URS at a pediatric hospital, with c-arms assigned by availability in the operating room. We performed dosimetry experiments using the same c-arms on standard phantoms. Results: Patient and case characteristics did not differ significantly between the two groups of patients. The median dose in the FPD group was less than a quarter of the dose in the CII group, 0.48 [0.42, 0.97] mGy vs 2.2 [1.1, 3.8] mGy, p < 0.0001. The FPD dose remained at less than one-third of the CII dose accounting for any difference in fluoroscopy time, and remained significant in a multivariate model including fluoroscopy time and patient weight (ß = 2.4, p = 0.007). Phantom studies showed higher image quality for FPDs at all simulated patient sizes, even at lower radiation doses. Conclusions: This is the first report comparing radiation dose from c-arms of image intensifiers and FPDs in adults or children. Use of an FPD during URS was associated with a substantially decreased absorbed dose for patients while simultaneously improving image quality.

Pharmacological Dilutional Therapy Using the Vasopressin Antagonist Tolvaptan for Young Patients With Cystinuria: A Pilot Investigation.

OBJECTIVE: To perform a pilot study of short-term safety, tolerability, and impact on urinary stone risk parameters of the vasopressin V2-receptor antagonist tolvaptan (which increases urinary excretion of free water) among adolescents and young adults with cystinuria. MATERIALS AND METHODS: We enrolled cystinuria patients age 12-25 years. Subjects were treated for 4 days at low-dose tolvaptan (0.3 mg/kg/day, maximum 30 mg) and 4 days at high dose (0.6 mg/kg/day, maximum 60 mg). Twenty-four-hour urine collections were done at baseline, day 3-4 of the dosing period, day 7-8 of the dosing period, and 3-6 days after washout. Primary outcome was cystine capacity (mg/L, target capacity > 0). Secondary outcomes included other urinary/serum parameters, tolerability, and thirst response. RESULTS: Two females (17, 23 years) and 2 males (13, 24 years) were enrolled. Cystine capacity respectively went from baseline of -312, -82, -353, and -628 mg/L to 97, 111, 75, and -3 mg/L on high dose (Figure 1). Twenty-four-hour volume went from 1.96, 3.0, 2.1, and 0.91 L to 11.74, 6.5, 9.9, and 2.8 L on high dose (Figure 2). There were no abnormalities in serum electrolytes or liver enzymes. Subjects did experience extreme thirst (9/10 on visual scale), but none discontinued treatment or reduced dose. CONCLUSION: Dilutional therapy with tolvaptan increased both cystine capacity and urinary volumes. This treatment approach has the potential to reduce recurrence of stones in this population. Further investigation should study longer term effects and safety, and determine optimal dosing to improve tolerability.

The effect of surgeon versus technologist control of fluoroscopy on radiation exposure during pediatric ureteroscopy: A randomized trial.

BACKGROUND: Fluoroscopy is commonly used during pediatric ureteroscopy (PURS) for urolithiasis, and the most important contributor to overall radiation exposure is fluoroscopy time (FT). One factor that may impact FT is who controls activation of the fluoroscope: the urologist (with a foot pedal) or the radiation technologist (as directed by the urologist). While there are plausible reasons to believe that either approach may lead to reduced FT, there are no systematic investigations of this question. We sought to compare FT with surgeon-control versus technologist control during PURS for urolithiasis. METHODS: We conducted a randomized controlled trial (Clinicaltrials.gov ID number: NCT02224287). Institutional Review Board approval was sought and obtained for this study. All subjects (or their legal guardians) provided informed consent. Each patient (age 5-26 years) was randomized to surgeon- or technologist-controlled fluoroscope activation. Block randomization was stratified by the surgeon. For technologist control, the surgeon verbally directed the technologist to activate the fluoroscope. For surgeon control, a foot pedal was used by the surgeon. The technologist controlled c-arm positioning, settings, and movement. The primary outcome was total FT for the procedure. Secondary outcomes included radiation exposure (entrance surface air kerma [ESAK] mGy). We also analyzed clinical and procedural predictors of FT and exposure. Mixed linear models accounting for clustering by surgeon were developed. RESULTS: Seventy-three procedures (5 surgeons) were included. The number of procedures per surgeon ranged from seven to 36. Forty-three percent were pre-stented. Thirty-one procedures were left side, 35 were right side, and seven were bilateral. Stones were treated in 71% of procedures (21% laser, 14% basket, and 65% laser/basket). Stone locations were distal ureter (11.5%), proximal/mid-ureter (8%), renal (69%), and ureteral/renal (11.5%). An access sheath was used in 77%. Median stone size was 8.0 mm (range 2.0-20.0). Median FT in the surgeon control group was 0.5 min (range 0.01-6.10) versus 0.55 min (range 0.10-5.50) in the technologist-control group (p = 0.284). Median ESAK in the surgeon control group was 46.02 mGy (range 5.44-3236.80) versus 46.99 mGy (range: 0.17-1039.31) in the technologist-control group (p = 0.362). Other factors associated with lower FT on univariate analysis included female sex (p = 0.015), no prior urologic surgeries (p = 0.041), shorter surgery (p = 0.011), and no access sheath (p = 0.006). On multivariable analysis only female sex (p = 0.017) and no access sheath (p = 0.049) remained significant. There was significant variation among surgeons (p < 0.0001); individual surgeon median FT ranged from 0.40 to 2.95 min. CONCLUSIONS: Fluoroscopy time and radiation exposure are similar whether the surgeon or technologist controls fluoroscope activation. Other strategies to reduce exposure might focus on surgeon-specific factors, given the significant variation between surgeons.

Granulomatous inflammation masquerading as an infected urachal cyst.

Errors in urachal obliteration may result in 4 clinical anomalies: patent urachus, urachal cyst, urachal sinus, or vesicourachal diverticulum. Despite the fact that urachal cysts are one of the more common of these anomalies, most go undetected, presenting in the setting of infection. There are reports in the literature of cysts misdiagnosed as other inflammatory processes; however, the converse is reported with less frequency. We present the case of a 3-year-old girl who was admitted to our institution with a suspected urachal cyst. This was subsequently diagnosed as a granulomatous mass caused by the gram negative bacterium Bartonella.

Patient and family impact of pediatric genitourinary diagnostic imaging tests.

PURPOSE: The impact of diagnostic genitourinary imaging on patients and families is poorly understood. We measured patient and family reaction to commonly performed genitourinary imaging studies using a standardized measurement tool. MATERIALS AND METHODS: We surveyed families undergoing genitourinary imaging (renal ultrasound, voiding cystourethrography, radionuclide cystogram, static renal scintigraphy and diuretic renal scintigraphy) using a Likert scaled 11-item survey to assess impact across 4 domains (pain, anxiety, time, satisfaction). Survey scores were analyzed using ANOVA and linear regression. RESULTS: A total of 263 families were surveyed (61 renal ultrasound, 52 voiding cystourethrogram, 55 radionuclide cystogram, 47 mercaptoacetyltriglycine dynamic renal scintigraphy, 48 dimercaptosuccinic acid static renal scintigraphy). Mean patient age was 2.1 years old. Of the patients 45% were male and 77% were white. Patient age, gender and prior genitourinary imaging experience varied by study type. Study type was significantly associated with total and weighted scores on the genitourinary imaging survey (both p <0.0001). Renal ultrasound was scored as better and mercaptoacetyltriglycine dynamic renal scintigraphy was worse than voiding cystourethrogram, radionuclide cystogram and dimercaptosuccinic acid static renal scintigraphy, which did not differ from each other. Other factors associated with worse total scores included patient age 1 to 3 years (p <0.001) and nonwhite race (p = 0.04). Gender, prior testing history, wait time and parent education were not associated with total scores. In the multivariate model renal ultrasound remained the best and mercaptoacetyltriglycine dynamic renal scintigraphy the worst (p <0.0001). In a direct comparison dimercaptosuccinic acid static renal scintigraphy and voiding cystourethrogram total scores did not differ (p = 0.59). CONCLUSIONS: There were significant differences among genitourinary imaging studies regarding the patient/family experience, but there was no overall difference between dimercaptosuccinic acid static renal scintigraphy and voiding cystourethrogram. These findings may be useful to aid decision making when considering genitourinary imaging for children.

Perioperative risk factors for surgical complications in pediatric urology: a pilot study in preoperative risk assessment in children.

OBJECTIVES: To elucidate which perioperative patient characteristics are associated with an increased risk of complications in pediatric urological surgery. There are numerous published studies that have correlated comorbidities, preoperative, and intraoperative parameters with postoperative outcomes in adults. However, there is a paucity of similar data in the pediatric population. METHODS: Between July 2003 and September 2006, a total of 93 children had an adverse or unexpected event within 35 days of urologic surgery. Thirty-eight preoperative patient characteristics and 20 perioperative parameters were evaluated. The severity of the complications was graded based on the Clavien classification. A total of 163 controls were randomly selected. Statistical significance was assessed by univariate and multivariate analysis. RESULTS: The overall complication rate was 1.1%. Most complications were technical in nature, occurred within 3 days after surgery, and classified as Clavien's grade 3 B. On multivariate analysis, weight less than fifth percentile, pulmonary or hematologic comorbidity, surgery duration >2 hours, first operation, low intraoperative heart rate, and the use of intravenous anesthesia were determined to be independent risk factors, whereas "other" medication was the only independent protective factor. CONCLUSIONS: We observed that some of the parameters conventionally thought to be risk factors for surgical complications such as multiple medical comorbidities, repeat operation, and American Society of Anesthesiologists' Classification of Physical Status score were not significant predictors of postoperative complications, whereas others were unexpectedly significant. Future prospective studies will be needed to fully stratify risk and guide risk interventions to improve postoperative outcomes.

What is the optimal surgical strategy for bulbous urethral stricture in boys?

PURPOSE: Optimal management for bulbous urethral stricture in children is poorly defined. We compared our long-term experience with direct vision internal urethrotomy and open repair to define the optimal surgical strategy. MATERIALS AND METHODS: We reviewed the records of 63 patients who underwent direct vision internal urethrotomy or open repair. A total of 46 patients (73%) were treated with 1 or more urethrotomies. Of the patients 17 (27%) underwent urethroplasty, 13 underwent end-to-end repair and 4 received a patch graft or tube. Eight of 17 cases required urethroplasty only, whereas in 9 combined open repair and urethrotomy were done. Mean patient age was 14.1 years (range 5 months to 21 years). Followup included voiding cystourethrogram, retrograde urethrogram and/or cystoscopy, or flow rate. Mean followup was 30 months for urethrotomy and 16 months for open urethroplasty. RESULTS: When direct vision internal urethrotomy was the initial approach, 1 procedure was successful in 28 of 53 cases (53%). Multiple urethrotomies increased the success rate to 59% (43 of 73 cases). The 53 patients with urethrotomy required a total of 84 procedures (mean 1.6 each). When open repair was the initial approach, 1 procedure was successful in 8 of 10 cases (80%). A total of 12 procedures (mean 1.2 each) were required in those 10 cases. A combined urethrotomy/open approach with 2 procedures was successful in 78% of cases (7 of 9). CONCLUSIONS: Open reconstruction is more successful than direct vision internal urethrotomy as the initial approach to bulbous urethral strictures. Although aggressive, end-to-end repair usually provides a definitive solution. Initial direct vision internal urethrotomy is successful in half of the cases and repeat urethrotomy adds little to success. The success of the combined urethrotomy/open approach approximates that of initial open reconstruction. If initial direct vision internal urethrotomy is elected, we advocate only 1 attempt, followed by open end-to-end urethroplasty if necessary.

Varicocele surgery: a decade's experience at a children's hospital.

OBJECTIVES: To review our experience at a children's hospital over a 10-year period with the Palomo, Ivanissevich, subinguinal and laparoscopic techniques for varicocele, assessing the success and complication rates according to specific procedure, and the added effect that the modifications of microsurgery and artery-sparing has had on these rates. A second objective was to assess the rate of testicular compensatory growth after surgery for testicular hypotrophy. PATIENTS AND METHODS: Ninety-two patients with >1 year of follow-up between 1996 and 2006 were assessed retrospectively. The median (range) age at surgery was 15 (8-21) years. Patients were stratified based on the surgical technique used by eight different urology faculty members. Microsurgery and attempted artery-sparing were applied to some Palomo, Ivannisevich, and subinguinal cases but not to laparoscopic procedures. RESULTS: The laparoscopic (100%) and Palomo (93%) techniques had significantly higher success rates than the Ivanissevich approach (69%). The success rate with the subinguinal technique (88%) was intermediate between the more successful supra-inguinal and less successful inguinal approaches. There was a higher hydrocele rate (32%) in the laparoscopic approach. Artery sparing significantly lowered hydrocele rates but had no effect on success rates. Incorporating microsurgery also had no effect on success rates but resulted in no hydrocele formation. One case of testicular atrophy occurred in a patient undergoing microsurgical artery-sparing subinguinal spermatic vein ligation. There was compensatory growth in 68% of patients operated on for testicular hypotrophy. CONCLUSIONS: During our 10-year experience the laparoscopic and Palomo approaches were the most successful. The subinguinal approach (usually incorporating microsurgery and artery sparing) had an intermediate success rate. The Ivanissevich approach was least successful. Hydroceles did not occur when microsurgery was used, and were significantly less common with artery sparing. The only case of testicular atrophy was with a microsurgical artery-sparing subinguinal approach. When the spermatic vein was ligated for testicular hypotrophy there was compensatory growth in two-thirds of testes.

Extracorporeal shock wave lithotripsy in pediatric patients using a late generation portable lithotriptor: experience at Children's Hospital Boston.

PURPOSE: Kidney stones in children are increasing in incidence. The continued evolution of stone treatment modalities, including shock wave lithotripsy, makes the assessment of continuous outcomes essential. We describe contemporary shock wave lithotripsy outcomes in pediatric patients. MATERIALS AND METHODS: A medical record review was performed of all patients younger than 20 years who underwent shock wave lithotripsy in 1998 to 2007. Patients were treated using a Dornier Compact Delta lithotriptor with ultrasound and fluoroscopic imaging. Subjects were defined as stone-free if imaging within 12 months showed no evidence of stones with no additional treatment. Patient and treatment factors associated with successful outcomes were analyzed. RESULTS: In 101 children a total of 114 treatment sequences were performed at a total of 150 shock wave lithotripsy sessions. Mean patient age was 10.5 years and 53% of the patients were girls. Mean stone diameter was 8 mm. Treatment was done for a solitary stone in 76% of cases, for 2 stones in 17% and for 3 or more in 7% with a mean shock count of 2,247. One, 2 and 3 or more treatment sessions were done in 78%, 16% and 6% of patients, respectively. The overall stone-free rate was 58.6%. However, the stone-free rate was only 12.5% after treatment sequences in 20 children with a history of anatomical urological conditions or surgery, while the stone-free rate in children without urological conditions was 67% (p <0.0001). Another factor associated with a decreased stone-free rate was stone size greater than 10 mm (25% vs 63%, p = 0.01). Complications included requiring acute reevaluation or treatment after 7% of shock wave lithotripsy sessions and 3.4% of patients required readmission. CONCLUSIONS: Extracorporeal shock wave lithotripsy is effective in many children with urolithiasis and it is well tolerated. However, in some children, particularly those with a history of urological surgery or congenital genitourinary conditions, success rates are low. These children may be best treated with other modalities.

Cryptorchidism and hypospadias.

PURPOSE: We quantified the burden of cryptorchidism and hypospadias in the United States by identifying trends in the use of health care resources and estimating the economic impact of the disease. MATERIALS AND METHODS: The analytical methods used to generate these results were described previously. RESULTS: Cryptorchidism is managed almost exclusively in the outpatient setting and insufficient data were available on inpatient health care use. Annual inpatient hospitalizations for hypospadias decreased by 75% between 1994 and 2000 from 2,669 (2.2/100,000 children) to 849 (0.6/100,000). Between 1992 and 2000 there were 611,647 physician office visits (96/100,000 per year) with undescended testis listed as the primary diagnosis. The rate of physician office visits for hypospadias by commercially insured boys younger than 3 years increased significantly from 429/100,000 in 1994 to 655/100,000 in 2002. The annualized rate of 18/100,000 in 1994 to 1996 remained relatively constant during these 3 years. Orchiopexy rates were highest in 0 to 2-year-old children, as generally recommended, but a substantial minority of these procedures was done in 3 to 10-year-old children. Geographic variation was noted with higher ambulatory surgery rates in the Northeast and Midwest than in the South and West. Data on commercially insured boys younger than 3 years revealed a 1.5-fold overall increase in the rate of hypospadias surgery from 321/100,000 in 1994 to 468/100,000 in 2002, reflecting the known increase in hypospadias incidence in the United States during the late 1990 s. CONCLUSIONS: Average cost per hospitalization for hypospadias exceeded $5,389 with costs per case higher in children 3 years or older, although there were more cases in children younger than 3 years. The cost per case of hypospadias was higher in the Northeast and South than in the other regions. Data on cryptorchidism are too sparse to provide insights into its downstream economic costs.

Vesicoureteral reflux and ureteroceles.

PURPOSE: We quantified the burden of vesicoureteral reflux and ureteroceles in the United States by identifying trends in the use of health care resources and estimating the economic impact of the diseases. MATERIALS AND METHODS: The analytical methods used to generate these results were described previously. RESULTS: Annual inpatient hospitalizations for vesicoureteral reflux increased slightly between 1994 and 2000 from 6.4/100,000 to 7.0/100,000 children, although this trend did not attain statistical significance. Inpatient hospitalization for ureteroceles remained relatively stable between 1994 and 2000 at an average of approximately 2,818 cases annually (1.0/100,000 to 1.1/100,000 children). The rates of visits to physician offices doubled during the 1990 s for commercially insured children (12/100,000 in 1994 and 26/100,000 in 2002) and children covered by Medicaid (43/100,000 in 1996 and 85/100,000 in 2000). Overall the rate of ambulatory surgery visits by commercially insured children increased from 3.4/100,000 in 1998 to 4.8/100,000 in 2002. Similar estimates were not available for children covered by Medicaid. Emergency room use by children with a primary diagnosis of vesicoureteral reflux was rare, reflecting the trend toward delivery of care at physician offices, ambulatory surgery centers and inpatient hospitals. No reliable data could be obtained on outpatient visits or ambulatory surgery for ureteroceles. In 2000 total expenditures for inpatient pediatric vesicoureteral reflux were $47 million, an increase of more than $10 million since 1997. Based on data from 2000 the yearly national inpatient expenditures from ureterocele treatment were an estimated $4 million. CONCLUSIONS: The economic impact of inpatient treatment for pediatric vesicoureteral reflux is considerable. If other service types such as pharmaceuticals, and outpatient and ambulatory services were considered, the observed impact of this condition would certainly be greater. Importantly the costs of prophylactic medical therapy and emerging therapies such as Deflux are not accounted for in this estimate. Furthermore, indirect economic costs, such as work loss to parents of children with pediatric vesicoureteral reflux, were not considered, causing an even greater underestimation of the true costs associated with the condition. Although the National Association of Children's Hospitals and Related Institutions, and the Health Care Cost and Utilization Project Kids' Inpatient Database include data on ureteroceles, the data were limited and, thus, they could not be used to determine reliable cost trends. Available data indicate that the mean cost per ureterocele case was almost $8,000 with little variation observed across ages, regions or sexes.

Renal cell carcinoma: Children's Hospital Boston experience.

OBJECTIVES: To review our experience to better define pediatric renal cell carcinoma (RCC). Pediatric RCC is rare, and recent data suggest it may be a unique disease. METHODS: A retrospective review was conducted of hospital and pathology records from 1965 to 2003. Patients with RCC were identified, and the clinical and pathologic data were extracted. RESULTS: Since 1965, 11 patients with RCC were treated, accounting for 3% of all renal tumors. In the first 20 years, 191 patients with renal tumor were treated, of whom 3 had RCC. In the most recent 15 years, 172 patients with renal tumor were treated, of whom 8 had RCC. The mean age at presentation was 14.7 years (range 9 to 17 years), with a female predominance (2.7:1). The clinical signs and symptoms included hematuria in 36%, flank pain in 27%, and an abdominal mass in 9%; 36% were discovered incidentally. Of the 11 RCC tumors, 45% were papillary and 55% were clear cell carcinoma. Papillary tumors presented at a worse stage and displayed more aggressive clinical behavior. Of 10 patients with available follow-up data, 6 had no evidence of RCC, 1 had died of other causes, 2 had died of metastatic RCC, and 1 was alive with recurrent RCC at a mean follow-up of 4.9 years. CONCLUSIONS: The clinical presentation, pathologic characteristics, and clinical behavior of pediatric RCC are different than those for adult RCC. A possible increasing incidence of RCC in children would parallel an increased incidence in adults. Our findings warrant additional and coordinated efforts to better characterize RCC in children.

Intermittent testicular torsion: diagnostic features and management outcomes.

PURPOSE: Intermittent testicular torsion (ITT) is a poorly characterized condition but harbors potentially serious implications with regard to testicular viability. We report better characterization of the diagnostic features of ITT. MATERIALS AND METHODS: We performed a retrospective review of all patients 1 to 18 years old seen from 1997 to 2003 at our institution diagnosed with ITT. Patients with acute scrotal pain and spontaneous resolution who underwent bilateral testicular fixation were included in the study. RESULTS: A total of 50 patients meeting the inclusion criteria were identified with mean age at presentation of 12.2 years (range 4 to 17). The mean number of painful episodes before surgery was 4.3 (range 1 to 30). The most common presenting features were severe pain of rapid onset and resolution. Nausea and/or vomiting was reported in a quarter of the patients. Finding of a horizontal lie of the testes on examination was significantly associated (p <0.05) with the existence of the bell-clapper deformity. All patients underwent surgical fixation of the testes. There were no postoperative complications. Of 38 patients (97%) for whom followup was available 37 had complete resolution of symptoms (mean followup 7.9 months). CONCLUSIONS: ITT should be a diagnostic consideration in patients who present with recurrent acute scrotal pain with rapid spontaneous resolution. Recurrent severe pain with rapid onset and resolution seems to be highly characteristic. Horizontal lie on examination is highly correlated with the bell-clapper deformity at surgical exploration. Surgery may be recommended in these patients as it appears to result in pain relief in the majority, is likely to prevent future testicular infarction and is associated with low morbidity.

Prepubertal testis tumors: actual prevalence rate of histological types.

PURPOSE: Tumor registries, urological textbooks and literature surveys all assert that yolk sac tumors are the most common primary testicular tumors in boys 12 years and younger. In contrast, several individual institutions have reported that benign tumors are more common than malignant tumors. To clarify these discordant findings, we surveyed the primary pathology records from 4 major pediatric centers. MATERIALS AND METHODS: The pathology records of the contributing centers were culled for primary testicular masses in boys 12 years and younger. Older boys and those with either paratesticular tumors or leukemia were excluded. The prevalence of each histological subtype was calculated from the pooled cases. RESULTS: A total of 98 patients met our criteria. Only 15% had yolk sac tumors. Teratomas comprised 48% of the tumors (mature 44%, immature 4%). Epidermoid cysts were found in another 14% of patients. Gonadal stromal cell tumors represented 13% of the total, divided among granulosa cell (5%), Leydig cell (4%), Sertoli cell (3%) and mixed gonadal stromal cell (1%). Other pathology, including cystic dysplasia (2), lymphoma (4), inflammatory pseudotumor (1) and gonadoblastoma (2), made up 9% of the total number of cases. CONCLUSIONS: We found that benign lesions represent the majority of primary testis tumors (74%), with the most common histological type being teratoma (48%). The reported high prevalence rates of prepubertal yolk sac tumors probably results from a reporting bias, since benign tumors are less likely to be submitted to tumor registries. Therefore, the primary operative approach to the majority of testis tumors in boys 12 years and younger should entail testis sparing surgery. Orchiectomy should be reserved for histologically confirmed malignancy based on increased preoperative alpha-fetoprotein and/or frozen section analysis of the tumor.

Urachal inflammatory myofibroblastic tumor with ALK gene rearrangement: a study of urachal remnants.

OBJECTIVES: Abnormalities of the urachus are rare among children and include a patent tract and cyst formation. These structures can also be affected by infection and abscess development. They are usually diagnosed during infancy and treated by surgical resection. Involvement of this remnant by either benign or malignant tumors is very infrequent. A few cases of mesenchymal tumors, such as desmoid tumor and leiomyoma, involving the urachus have been described in published reports. METHODS: We studied an inflammatory myofibroblastic tumor arising from the urachus in a 10-year-old boy. In addition, we reviewed 101 cases of urachal remnants retrieved from the surgical pathology and autopsy files in the Department of Pathology at the Children's Hospital Boston diagnosed in the past 82 years. RESULTS: The urachal inflammatory myofibroblastic tumor showed anaplastic lymphoma kinase (ALK) rearrangement by immunohistochemistry and fluorescence in situ hybridization techniques. No other neoplasms were diagnosed in the analyzed population. CONCLUSIONS: We describe an example of inflammatory myofibroblastic tumor involving the urachus. Involvement of the urachus by tumors is rare, but these should be considered in the differential diagnosis of urachal lesions.