Outcomes based on histopathologic response to preoperative chemotherapy in children with bilateral Wilms tumor: A prospective study (COG AREN0534).

BACKGROUND: An objective of the Children's Oncology Group AREN0534 Study was to improve the survival of patients with bilateral Wilms tumors (BWT) by using preoperative chemotherapy of limited duration and tailoring postoperative therapy based on histopathologic response. The authors report outcomes based on postoperative histopathologic responses. METHODS: Patients with BWT received treatment with vincristine, dactinomycin, and doxorubicin for 6 or 12 weeks followed by surgery. Postoperative therapy was prescribed based on the highest risk tumor according to the International Society of Pediatric Oncology classification and the Children's Oncology Group staging system. RESULTS: Analyses were performed on data from 180 evaluable children. The 4-year event-free survival (EFS) and overall survival (OS) rates were 81% (95% CI, 74%-87%) and 95% (95% CI, 91%-99%), respectively. Seven patients who had completely necrotic tumors had a 4-year EFS rate of 100%. Of 118 patients who had tumors with intermediate-risk histopathology, the 4-year EFS and OS rates were 82% (95% CI, 74%-90%) and 97% (95% CI, 94%-100%), respectively. Fourteen patients who had blastemal-type tumors had 4-year EFS and OS rates of 79% (95% CI, 56%-100%) and 93% (95% CI, 79%-100%), respectively. Eighteen patients who had diffuse anaplasia had 4-year EFS and OS rates of 61% (95% CI, 35%-88%) and 72% (95% CI, 47%-97%), respectively; and the 4-year EFS and OS rates of 7 patients who had focal anaplasia were 71% (95% CI, 38%-100%) and 100%, respectively. There was no difference in the outcomes of patients who had different histopathologic subtypes within the intermediate-risk group (P = .54). CONCLUSIONS: A risk-adapted treatment approach for BWT results in excellent outcomes. This approach was not successful in improving the outcome of patients who had diffuse anaplasia.

Impact of cyclophosphamide and etoposide on outcome of clear cell sarcoma of the kidney treated on the National Wilms Tumor Study-5 (NWTS-5).

PURPOSE: To improve the event-free survival (EFS) and overall survival (OS) for patients with clear cell sarcoma of the kidney (CCSK) by incorporating cyclophosphamide and etoposide into treatment on National Wilms Tumor Study (NWTS)-5. PATIENTS AND METHODS: Patients less than 16 years of age with a centrally confirmed pathological diagnosis of CCSK were eligible for treatment on this prospective single-arm study conducted between August 1995 and June 2002. Staging consisted of CT scans of chest, abdomen, pelvis, bone scan, skeletal survey, and CT or MRI of the head. Treatment consisted of vincristine/doxorubicin/cyclophosphamide alternating with cyclophosphamide/etoposide for 24 weeks and radiation to sites of disease. RESULTS: One hundred eight eligible patients were enrolled on study (69% males, 63% Caucasian), with a median age of 22 months. Stage distribution was as follows: stage I, 12; II, 44; III, 45; IV, 7. Median follow-up was 9.7 years. Five-year EFS and OS were 79% (95% CI: 71%-88%) and 90% (95% CI: 84%-96%). Five-year EFS for stage I-IV was 100%, 88%, 73%, and 29%, respectively. Twenty of the 23 disease-related events occurred within three years of initial treatment. The most common site of recurrence was brain (12/23). CONCLUSION: The outcome for patients with CCSK treated on NWTS-5 was similar to NWTS-4 and accomplished over a shorter treatment duration. Stage was highly predictive of outcome. Brain metastases occurred more frequently than on NWTS-4. Regimen I showed more benefit for patients with stage I and II disease as compared with higher stages of disease where new therapies are needed.

Results of the First Prospective Multi-institutional Treatment Study in Children With Bilateral Wilms Tumor (AREN0534): A Report From the Children's Oncology Group.

OBJECTIVE: The Children's Oncology Group study AREN0534 aimed to improve event-free survival (EFS) and overall survival (OS) while preserving renal tissue by intensifying preoperative chemotherapy, completing definitive surgery by 12 weeks from diagnosis, and modifying postoperative chemotherapy based on histologic response. BACKGROUND: No prospective therapeutic clinic trials in children with bilateral Wilms tumors (BWT) exist. Historical outcomes for this group were poor and often involved prolonged chemotherapy; on NWTS-5, 4-year EFS for all children with BWT was 56%. METHODS: Patients were enrolled and imaging studies were centrally reviewed to assess for bilateral renal lesions. They were treated with 3-drug induction chemotherapy (vincristine, dactinomycin, and doxorubicin) for 6 or 12 weeks based on radiographic response followed by surgery and further chemotherapy determined by histology. Radiation therapy was provided for postchemotherapy stage III and IV disease. RESULTS: One hundred eighty-nine of 208 patients were evaluable. Four-year EFS and OS were 82.1% (95% CI: 73.5%-90.8%) and 94.9% (95% CI: 90.1%-99.7%. Twenty-three patients relapsed and 7 had disease progression. After induction chemotherapy 163 of 189 (84.0%) underwent definitive surgical treatment in at least 1 kidney by 12 weeks and 39% retained parts of both kidneys. Surgical approaches included: unilateral total nephrectomy with contralateral partial nephrectomy (48%), bilateral partial nephrectomy (35%), unilateral total nephrectomy (10.5%), unilateral partial nephrectomy (4%), and bilateral total nephrectomies (2.5%). CONCLUSION: This treatment approach including standardized 3-drug preoperative chemotherapy, surgical resection within 12 weeks of diagnosis and response and histology-based postoperative therapy improved EFS and OS and preservation of renal parenchyma compared with historical outcomes for children with BWT.

A Society for Pediatric Urology Workforce Survey on the Current Perceptions of Oncology Care by Pediatric Urologists: A Report from the Pediatric Urologic Oncology Working Group of the Society for Pediatric Urology.

PURPOSE: Data are lacking on the current perception of oncology care among pediatric urologists. Thus, we developed, pilot tested and administered a survey on this topic to SPU (Society for Pediatric Urology) members. MATERIALS AND METHODS: Approval for this proposal was granted by SPU leadership prior to developing or distributing the survey instrument. The survey was developed and pilot tested by the PUOWG (Pediatric Urologic Oncology Working Group). Response data were collected and descriptive statistics were used for analysis. Logistic regression analysis was performed to correlate surgeon reported factors with higher volumes of reported oncology surgery. RESULTS: A total of 426 surveys were distributed via email to SPU members and 212 individual surveys (49.8%) were returned with the background/introduction section completed. Of these surveys 200 (94.3%) were completed by practicing pediatric urologists. Overall, 155 respondents (77.5%) reported performing 5 or fewer oncology related surgeries per year and 74.9% reported that less than 25% of renal tumor surgery at their institution was performed through the pediatric urology service. On multivariate analysis the self-reported factors significantly associated with increased oncology surgical volume (more than 5 cases per year) were greater than 50% attendance at institutional tumor board meetings (OR 4.8, 95% CI 1.4-16.9) and practicing at a hospital with a higher volume of renal tumor surgery (OR 2.6, 95% CI 1.2-5.8). CONCLUSIONS: Few surveyed pediatric urologists reported performing a high volume of oncology surgery. Respondents expressed interest in ways to increase pediatric urology involvement in oncology care, including opportunities for increased education. Self-reported factors that correlated with higher volume were regular attendance at the institutional pediatric tumor board and practice at a higher volume institution.

Patterns of Performance of Oncologic Surgery by North American Pediatric Urologists: A Report from the Pediatric Urologic Oncology Working Group of the Society for Pediatric Urology.

PURPOSE: Objective data on patterns of oncology practice among pediatric urologists are lacking. We reviewed surgical case logs submitted to the American Board of Urology by those self-reporting as pediatric urologists. We hypothesized that logs would reveal a low oncology volume (fewer than 5 cases) and identify orchiectomy as the most common oncology cases, and that less than 25% of logs would show nephrectomy for renal tumor. MATERIALS AND METHODS: Case logs submitted for American Board of Urology certification, recertification or pediatric subspecialty certification were reviewed and standardized to represent 12-month practice. Data were collected on pediatric oncologic surgeries as noted by procedure codes linked with oncologic diagnosis codes for patients up to age 30 years. RESULTS: We identified 281 case logs meeting study criteria. A total of 364 oncology cases were logged and 131 logs (46.6%) listed at least 1 oncology case, while 150 (53.4%) contained no oncology cases. The 75th, 90th and 95th percentiles of oncology volume were represented by reporting 2, 3 and 4 cases, respectively. A total of 13 logs (4.6%) accounted for more than a third of all oncology cases (35.9%). The most frequent oncology case logged was orchiectomy, which was documented in 83 logs (29.5%). On Poisson regression surgeon variables associated with higher oncology volume included male gender (IRR 2.8, 95% CI 2.1-3.9), 2010 log year (IRR 2.4, 95% CI 1.3-4.4), 2015 log year (IRR 3.7, 95% CI 2.1-6.4) and nonpediatric subspecialty certification log (IRR 1.6, 95% CI 1.2-2.3). CONCLUSIONS: Few pediatric urologists perform a high volume of oncologic surgeries based on surgical case logs submitted to the American Board of Urology. A small cohort of pediatric urologists logged the majority of such cases.

Outcome of patients with Stage II/favorable histology Wilms tumor with and without local tumor spill: a report from the National Wilms Tumor Study Group.

BACKGROUND: Intra-operative tumor spill increases the risk of local recurrence of Wilms tumor, and adversely impacts relapse-free (RFS) and overall survival (OS) rates. METHODS: Surgical checklists, operative notes, institutional pathology reports, central pathology review and flow sheets of 602 patients registered between August 1986 and September 1994 on National Wilms Tumor Study-4 as randomized, followed or switched and coded as Final Stage II, favorable histology (FH) were reviewed. RFS and OS were estimated using the Kaplan-Meier method. Hazard ratios (HRs) were estimated using the Cox model and tested for statistical significance by the log-rank test. RESULTS: Four hundred ninety-nine patients were found after review to have Stage II, FH Wilms tumor. The 8-year RFS percentages were 85.0% (95% confidence interval (CI): 81.1%, 88.1%) for those with no spill compared to 75.7% (65.8%, 83.2%) for those with spill. The 8-year OS percentages were 95.6% (93.1%, 97.3%) for those with no spill compared to 90.3% (82.2%, 94.9%) for those with spill. The HR for relapse among those with spill was 1.55 ((95%CI: 0.97,2.51), P = 0.067) and the HR for death was 1.94 ((0.92,4.09), P = 0.077). CONCLUSIONS: RFS and OS were lower for patients who had intra-operative tumor spill. The majority of NWTS Stage II, FH patients with intra-operative tumor spill have an overall excellent outcome when treated with two drug chemotherapy (vincristine and actinomycin D) and no abdominal irradiation.

Treatments and outcomes for end-stage renal disease following Wilms tumor.

BACKGROUND: Little is known about treatment outcomes for children who have end-stage renal disease (ESRD) after treatment for Wilms tumor (WT). METHODS: Time-to-transplant, graft failure, and survival outcomes were examined for 173 children enrolled on the National Wilms Tumor Study who developed ESRD. RESULTS: Fifty-five patients whose ESRD resulted from progressive bilateral WT (PBWT) experienced high early mortality from WT that limited their opportunity for transplant (47% at 5 years) and survival (44% at 10 years) in comparison to population controls. The 118 patients whose ESRD was due to other causes (termed "chronic kidney disease"), many of whom had WT-associated congenital anomalies, had transplant (77% at 5 years) and survival (73% at 10 years) outcomes no worse than those for population controls. Graft failure following transplant was comparable for the two groups. Minority children had twice the median time to transplant as non-Hispanic whites and twice the mortality rates, also reflecting population trends. CONCLUSIONS: In view of the continuing high mortality in patients with ESRD, and the dramatic improvement in outlook following kidney transplantation, re-evaluation of current guidelines for a 2-year delay in transplant following WT treatment may be warranted.

The management of synchronous bilateral Wilms tumor: a report from the National Wilms Tumor Study Group.

OBJECTIVE: To provide guidelines for future trials, we reviewed the outcomes of children with synchronous bilateral Wilms tumors (BWT) treated on National Wilms Tumor Study-4 (NWTS-4). METHODS: NWTS-4 enrolled 3335 patients including 188 patients with BWT (5.6%). Treatment and outcome data were collected. RESULTS: Among 188 BWT patients registered with NWTS-4, 195 kidneys in 123 patients had initial open biopsy, 44 kidneys in 31 patients had needle biopsies. Although pre-resection chemotherapy was recommended, 87 kidneys in 83 patients were managed with primary resection: Complete nephrectomy 48 in 48 patients, 31 partial/wedge nephrectomies in 27 patients, enucleations 8 in 8 patients. No initial surgery was performed in 45 kidneys in 43 patients, 5 kidneys in 3 patients not coded. Anaplasia was diagnosed after completion of the initial course of chemotherapy in 14 patients (initial surgical procedure: 9 open biopsies, 4 needle biopsies, 1 partial nephrectomy). The average number of days from the start of chemotherapy to diagnosis of anaplasia was 390 (range 44-1925 days). Relapse or progression of disease occurred in 54 children. End stage renal failure occurred in 23 children, 6 of whom had bilateral nephrectomies. The 8 year event free survival for BWT with favorable histology was 74%, and overall survival was 89%; whereas the event free survival for BWT with unfavorable histology was 40%, overall survival was 45%. CONCLUSION: The current analysis of patients with BWT treated on NWTS-4 shows that preservation of renal parenchyma is possible in many patients after initial preoperative chemotherapy. The incidence of end-stage renal disease remains significantly higher in children with BWT. Future studies are warranted to address the need for earlier biopsy in nonresponsive tumors and earlier definitive surgery to recognize unfavorable histology in these high-risk patients.

Do chief resident scores on the in-service examination predict their performance on the American Board of Urology Qualifying Examination?

PURPOSE: The American Urological Association In-Service Examination and the American Board of Urology Qualifying Examination are written multiple choice tests that cover all domains in urology. We investigated whether In-Service Examination performance could identify chief residents who scored in the lowest quartile on the Qualifying Examination. MATERIALS AND METHODS: All urology chief residents in the United States and Canada in 2008 and 2009 were eligible to participate in this study. In-Service Examination 2008 and Qualifying Examination 2009 performance data were obtained from the American Urological Association and American Board of Urology, respectively. Data were analyzed with the Pearson correlation and descriptive statistics. RESULTS: Of the 257 American and Canadian chief residents who completed the Qualifying Examination 2009, 194 (75%) enrolled in this study and were included in analysis. Overall In-Service Examination 2008 scores correlated significantly with Qualifying Examination 2009 scores (r=0.55, p<0.001), accounting for 30% of score variance. Substantial variability in In-Service Examination-Qualifying Examination rankings was notable among individual residents. An In-Service Examination 2008 cutoff percentile rank of 40% identified chief residents in the lowest quartile on the Qualifying Examination 2009 with 71% sensitivity, 77% specificity, and a likelihood ratio of 3.1 and 0.4 (positive and negative likelihood ratios, respectively). CONCLUSIONS: The substantial variability of In-Service Examination-Qualifying Examination performance among individual chief residents limits In-Service Examination predictive utility. A single In-Service Examination score should not be used to make a high stakes judgment about an individual resident. In-Service Examination scores should be used as 1 part of an overall evaluation program to prospectively identify residents who could benefit from additional educational support.

Risk factors for end stage renal disease in non-WT1-syndromic Wilms tumor.

PURPOSE: We assessed risk factors for end stage renal disease in patients with Wilms tumor without known WT1 related syndromes. We hypothesized that patients with characteristics suggestive of a WT1 etiology (early onset, stromal predominant histology, intralobar nephrogenic rests) would have a higher risk of end stage renal disease due to chronic renal failure. We predicted a high risk of end stage renal disease due to progressive bilateral Wilms tumor in patients with metachronous bilateral disease. MATERIALS AND METHODS: End stage renal disease was ascertained in 100 of 7,950 nonsyndromic patients enrolled in a National Wilms Tumor Study during 1969 to 2002. Risk factors were evaluated with cumulative incidence curves and proportional hazard regressions. RESULTS: The cumulative incidence of end stage renal disease due to chronic renal failure 20 years after Wilms tumor diagnosis was 0.7%. For end stage renal disease due to progressive bilateral Wilms tumor the incidence was 4.0% at 3 years after diagnosis in patients with synchronous bilateral Wilms tumor and 19.3% in those with metachronous bilateral Wilms tumor. For end stage renal disease due to chronic renal failure stromal predominant histology had a HR of 6.4 relative to mixed (95% CI 3.4, 11.9; p<0.001), intralobar rests had a HR of 5.9 relative to no rests (95% CI 2.0, 17.3; p=0.001), and Wilms tumor diagnosis at less than 24 months had a HR of 1.7 relative to 24 to 48 months and 2.8 relative to greater than 48 months (p=0.003 for trend). CONCLUSIONS: Metachronous bilateral Wilms tumor is associated with high rates of end stage renal disease due to surgery for progressive Wilms tumor. Characteristics associated with a WT1 etiology markedly increased the risk of end stage renal disease due to chronic renal failure despite the low risk in non-WT1 syndromic cases overall.

Long-term outcomes for infants with very low risk Wilms tumor treated with surgery alone in National Wilms Tumor Study-5.

OBJECTIVE: To determine the event-free survival (EFS) and overall survival (OS) of children with very low risk Wilms tumor (VLRWT) treated with surgery only. BACKGROUND: Previous studies suggested that postoperative chemotherapy had not improved the prognosis of children with VLRWT. A total of 77 children <24 months of age with small (<550 g) Stage I favorable histology Wilms tumors were treated with surgery only. This study was closed based on stopping rules to ensure that the 2-year EFS was > or =90%. METHODS: A total of 77 children were assessed for EFS and OS. Of these patients, 21 enrolled at the time of closure were recalled, treated with dactinomycin and vincristine (regimen EE4A), and censored for analysis thereafter. About 111 children subsequently treated with EE4A were available for comparison. RESULTS: Median follow-up of surviving patients was 8.2 years for surgery only (range, 1.9-11.8 years) and 5.2 years for the EE4A group (range, 1.6-8.9 years). The estimated 5-year EFS for surgery only was 84% (95% confidence interval [CI]: 73%, 91%); for the EE4A patients it was 97% (95% CI: 92%, 99%, P = 0.002). One death was observed in each treatment group. The estimated 5-year OS was 98% (95% CI: 87%, 99%) for surgery only and 99% (95% CI: 94%, 99%) for EE4A (P = 0.70). CONCLUSION: The surgery-only EFS was lower than anticipated but, coupled with a much higher than anticipated salvage rate of the chemotherapy naive patients whose disease recurred, led to an observed long-term OS equivalent to that seen with 2-drug chemotherapy. This approach to the treatment of patients with VLRWT eliminates the toxic side-effects of chemotherapy for a large majority of patients. A follow-up study is underway to confirm these findings.

Neonatal orchitis mimicking cystic dysplasia of the testis.

Neonatal orchitis is an extremely rare disease, usually related to a congenital genitourinary anomaly. We present a 36 weeks' gestation infant who presented at 3 days old with a firm and enlarged right testicle. Testicular US revealed a heterogeneous right testicle with numerous cystic spaces as well as decreased testicular blood flow. The clinical concerns included testicular tumor and cystic dysplasia of the testis because of concurrent renal dysplasia. The scrotal/testicular area was without tenderness or overlying erythema. Radical inguinal orchiectomy revealed diffuse gram-negative orchitis.This case represents an atypical presentation of orchitis. This entity should be added to the differential diagnoses of testicular mass in the neonate even in the absence of physical findings suggestive of infection.

Interactive spaced education to assess and improve knowledge of clinical practice guidelines: a randomized controlled trial.

OBJECTIVE: To determine whether Interactive Spaced Education (ISE) is an effective and acceptable form of graduate and continuing medical education (GME/CME), using clinical practice guideline (CPG) education as an experimental system. SUMMARY BACKGROUND DATA: ISE is a novel form of online education, which combines the pedagogical merits of the spacing and testing effects. Its efficacy for GME and CME is not known. METHODS: One-hundred sixty urologists and 320 urology residents were randomized to 1 of 2 cohorts. We developed and validated 48 ISE items (questions and answers) on 5 urology CPGs (hematuria and priapism [HP]; staghorn calculi, infertility, and antibiotic use [SIA]). Physicians were sent 3 emails a week, each containing 2 questions. Content was repeated 3 times over 20 weeks. Cohort A physicians received the 3-cycle ISE course on HP, with 24 control items on SIA in cycle 3. Cohort B physicians received the 3-cycle ISE course on SIA, with 24 control items on HP in cycle 3. RESULTS: The ISE program was completed by 71% urologists and 83% residents. Cohort A scores on HP increased from mean 44.9% in cycle 1% to 75.7% in cycle 3, a 57% relative increase compared with controls (P < 0.001; Cohen effect size, 2.2). Similarly, cohort B scores on SIA increased from 45.2% in cycle 1% to 69.5% in cycle 3, a 56% relative increase compared with controls (P < 0.001; effect size, 2.2). Eighty-four percent of all participants requested to enroll in further ISE programs. CONCLUSIONS: ISE is an effective and well-accepted form of GME and CME and is a promising new methodology to improve CPG knowledge.

Hepatic metastasis at diagnosis in patients with Wilms tumor is not an independent adverse prognostic factor for stage IV Wilms tumor: a report from the Children's Oncology Group/National Wilms Tumor Study Group.

OBJECTIVE: To determine event free survival (EFS) of children with Wilms tumor (WT) and metastatic liver disease at diagnosis. SUMMARY AND BACKGROUND DATA: We reviewed patients with stage IV Wilms tumor treated on National Wilms Tumor Study 4 and 5 to ascertain if they have a worse prognosis than other Stage IV disease. METHODS: A total of 742 patients (pts) with stage IV disease were assessed for EFS (95% confidence interval [CI]) at 5 years after diagnosis. Cohorts included those who underwent resection of the liver lesions compared with those who received only chemotherapy and radiotherapy. RESULTS: A total of 742 patients with stage IV Wilms tumor were enrolled on NWTS-4 and 5, 111 of who had liver metastases. Of these, 96 had favorable histology disease and are the focus of this analysis. Twenty-two patients had a primary liver resection (wedge resection, 18 and lobectomy, 4). After chemotherapy and/or radiation, 13 patients underwent liver resection (wedge resection, 7; lobectomy, 5; and trisegmentectomy, 1). Seventy-one patients (67%) did not undergo surgery for their liver disease. In 14 patients, the liver disease disappeared with chemotherapy only. Eighty-two patients received abdominal radiation. EFS for the patients with metastatic FH Wilms tumor was 75% (95% confidence interval [CI]: (71%, 78%), EFS by Stage IV category was: lung only 76% (95% CI: 72%, 80%) (513 patients); liver, not lung 76% (95% CI: 58%, 87%) (34 patients), liver and lung 70% (95% CI: 57%, 80%) (62 patients), and other sites 64% (95% CI: 42%, 79%) (25 patients). There were no significant differences among stage IV groups (P = 0.60). EFS (95% CI) for the patients with primary resection of the liver metastases (22 patients) was 86% (63%, 95%) compared with 68% (56%, 78%) (P = 0.09) for the 74 with no primary resection of liver metastases. There was no significant difference in EFS for patients with FH Wilms tumor treated with chemotherapy compared with that of patients treated with chemotherapy and radiation (P = 0.63). The EFS (95% CI) for each of the subsets was; no abdominal radiation: 64% (34%, 83%); abdominal radiation, no boost: 77% (55%, 89%); abdominal radiation, boost: 72% (58%, 82%) (P = 0.05). CONCLUSION: Liver metastasis at diagnosis is not an adverse prognostic factor for stage IV metastatic FH WT.

Renal failure does not preclude cure in children receiving chemotherapy for Wilms tumor: a report from the National Wilms Tumor Study Group.

BACKGROUND: Children with Wilms tumor can develop renal failure during treatment. Since there are few published data concerning the appropriate chemotherapy for this situation, we reviewed the experience of children who developed renal failure while being treated on National Wilms Tumor Study Group (NWTSG) studies 1-4 (1969-1994). PATIENTS AND METHODS: Data files in the NWTSG Data Center for all patients with Wilms tumor were screened. Patient demographics and tumor and treatment data were abstracted from those who developed renal failure. RESULTS: Twenty-eight of 5,910 (0.47%) children with Wilms tumor registered on NWTSG studies I through IV (1971-1994) were treated with chemotherapy after developing renal failure. Among these patients vincristine at full dose (0.05 mg/kg dose) did not increase the risk of severe toxicity. Dactinomycin (full dose: 15 mcg/kg day x 5) increased the risk for severe neutropenia when given at 75-100% of full dose. There was no compelling evidence for increased toxicity of doxorubicin when given at 100% versus 50% dosing (full dose: 20 mg/m(2) day x 3), but the number of patients analyzed was small. The overall survival percentage was 39%, but 64% for those patients who were in their initial treatment phase at the time of renal failure. CONCLUSION: The data suggest that, in the setting of renal failure, reduction of dosing is not necessary for the three main agents used for treatment of newly diagnosed Wilms tumor, and cure is not precluded. Accurate pharmacologic and pharmacokinetic studies are needed for any patient being treated while in renal failure.

Treatment of Wilms tumor relapsing after initial treatment with vincristine, actinomycin D, and doxorubicin. A report from the National Wilms Tumor Study Group.

OBJECTIVE: We evaluated the use of alternating cycles of cyclophosphamide/etoposide and carboplatin/etoposide in children entered on National Wilms Tumor Study (NWTS)-5 who were diagnosed between August 1, 1995 and May 31, 2002 and who relapsed after chemotherapy with vincristine, actinomycin D, and doxorubicin (VAD) and radiation therapy (DD-4A). PATIENTS AND METHODS: One hundred three patients who relapsed or had progressive disease after initial VAD chemotherapy and radiation therapy were registered on stratum C of the NWTS-5 Relapse protocol. Twelve patients were not evaluable: five due to insufficient data, six due to major protocol violations, and one for refusal of therapy. Among the 91 remaining patients, 14 with stage V Wilms tumor (WT), 1 with contralateral relapse, and 16 who did not achieve a complete response (CR) to the initial three-drug chemotherapy were not included in this analysis. Relapse treatment included alternating courses of the drug pairs cyclophosphamide/etoposide and carboplatin/etoposide, surgery, and radiation therapy. RESULTS: The outcomes of 60 patients were analyzed. The lung was the only site of relapse for 33 patients; other sites of relapse included the operative bed, the abdomen, and liver. Four-year event-free survival (EFS) and overall survival (OS) were 42.3 and 48.0% respectively for all patients and were 48.9 and 52.8% for those who relapsed in the lungs only. Thrombocytopenia was the most frequent toxicity. CONCLUSION: These results demonstrate that approximately one-half of children with unilateral WT who relapse after initial treatment with VAD and radiation therapy can be successfully retreated.

Loss of heterozygosity for chromosomes 1p and 16q is an adverse prognostic factor in favorable-histology Wilms tumor: a report from the National Wilms Tumor Study Group.

PURPOSE: To determine if tumor-specific loss of heterozygosity (LOH) for chromosomes 1p or 16q is associated with a poorer prognosis for children with favorable-histology (FH) Wilms tumor entered on the fifth National Wilms Tumor Study (NWTS-5). PATIENTS AND METHODS: Between August 1995 and June 2002, 2,021 previously untreated children with FH or anaplastic Wilms tumor, clear-cell sarcoma of the kidney (CCSK) or malignant rhabdoid tumor of the kidney (RTK), were treated with stage- and histology-specific therapy. Their tumors were assayed for LOH for polymorphic DNA markers on chromosomes 1p and 16q. ResultsLOH for 1p or 16q was rarely observed in CCSK (n = 90) or RTK (n = 22). The relative risk (RR) of relapse for patients with FH stage I to IV tumors with LOH, stratified by stage, was 1.56 for LOH 1p (P = .01) and 1.49 for LOH 16q (P = .01), whereas the RR of death was 1.84 (P = .03) and 1.44 (P = .15), respectively. When the effects of LOH for both regions were considered jointly among patients with stage I to II FH disease, the risks of relapse and death were increased for LOH 1p only (RR = 2.2, P = .02 for relapse; RR = 4.0, P = .02 for death), for LOH 16q only (RR = 1.9, P = .01 and RR = 1.4, P = .60) and for LOH for both regions (RR = 2.9, P = .001 and RR = 4.3, P = .01) in comparison with patients with LOH at neither locus. The risks of relapse and death for patients with stage III to IV FH tumors were increased only with LOH for both regions (RR = 2.4, P = .01 and RR = 2.7, P = .04). CONCLUSION: Tumor-specific LOH for both chromosomes 1p and 16q identifies a subset of FH Wilms tumor patients who have a significantly increased risk of relapse and death. LOH for these chromosomal regions can now be used as an independent prognostic factor together with disease stage to target intensity of treatment to risk of treatment failure.