Renal function and outcome following salvage surgery for bilateral Wilms' tumor

Surgery in Bilateral Wilms Tumor-A Single-Center Experience

The treatment of bilateral Wilms tumors (BWT) involves curing the cancer, preserving long-term renal function, and maintaining a good quality of life. Established methods for achieving these goals include preoperative chemotherapy and nephron-sparing surgery (NSS). This study aimed to evaluate the experience of a single institution in treating patients with BWT. We analyzed cases of BWT treated at the Pediatric Oncology Institute-GRAACC-Federal University of São Paulo over a period of 35 years. Bleeding control was performed with manual compression of the renal parenchyma. Thirty-three patients were included in the study. Thirty cases were synchronous tumors. The mean age at diagnosis was 30.4 months (±22 m) and 66.7% were girls. The median follow-up period was 83 months. Neoadjuvant chemotherapy was the primary approach in most patients (87.9%), with a simultaneous upfront surgical approach performed in 84.8%. Most patients underwent bilateral NSS (70.4%). There were no early complications in this series, but 39.4% had clinical complications. The five-year survival rate was 76%. Therefore, it is clear that the surgical approach to BWT plays a crucial role in achieving good outcomes. However, it is difficult to standardize surgical techniques and technology may have the potential to enhance safety.

Bench surgery with autotransplantation for bilateral Wilms tumor-A feasible technique for renal sinus invasion

Purpose

Bilateral Wilms tumor (BWT) with renal sinus invasion requires extremely difficult surgical care. This study presents an alternative strategy for tumor removal while at the same time preserving the renal parenchyma.

Materials and methods

In total, 9 cases of synchronous BWT were admitted to our hospital between May 2016 to Aug 2020. We retrospectively reviewed the clinical data, surgical technique, and functional and oncological outcomes of these cases.

Results

The 9 cases included 3 males and 6 females, with a median age of 12 months at surgery (range 7-40). A total of 14 kidney units had renal sinus invasion (77.8%), whereas multifocal neoplasms were observed in 7 units (38.9%). The local stage distribution revealed 1 kidney with stage I, 10 kidneys with stage II, and 7 kidneys with stage III. Nephron-sparing surgery was performed on 15 kidney units (83.3%), among which 13 (72.2%) underwent bench surgery with autotransplantation (BS-AT), whereas 2 (11.1%) were subjected to tumor enucleation in vivo. Urinary leakage was the most prevalent postoperative complication. We observed negative margins. During the mean follow-up of 28.4 months, 2 patients (22.2%) succumbed from sepsis and renal failure, respectively, whereas the other 7 (77.8%) survived without recurrence. Survivors experienced an estimated glomerular filtration rate of 81 ± 15.4 ml/(min × 1.73 m²). The endpoint renal volume of 9 renal units receiving BS-AT significantly increased (P = 0.02).

Conclusions

In summary, the surgical management of bilateral Wilms tumor requires meticulous operative approach and technique. Besides, BS-AT provides a viable alternative to nephron-sparing surgery for BWT patients with renal sinus invasion.

Early postoperative complications in pediatric abdominal solid tumor surgery according to Clavian-Dindo classification

PURPOSE

Postoperative period after abdominal solid tumor surgery is critical regarding complications. This study aimed to detect incidence and treatment of complications.

METHODS

Single center retrospective study including years 2010-2019 for early postoperative complications were documented and graded according to Clavian-Dindo classification.

RESULTS

The overall complication rate was 10% and they were chylous leak (n = 8, 2%), collection in surgical field (n = 8, 2%), acute renal failure (n = 7, 1.7%), hemorrhage (n = 5, 1.3%), intestinal obstruction (n = 4, 1%), surgical site infection (n = 3, 0.7%), thromboembolism (n = 3, 0.7%) and peripheric neuronal event (n = 2, 0.5%). Distribution of complications according to Clavian-Dindo classification was as follows: 2 grade I, 23 grade II, 9 grade IIIb, 5 grade IVa and 1 grade V. While age and percentage of benign or malignant disease were not different in groups with or without complications (p = 0.11, p = 0.24), males had more complications than female patients (p = 0.008). Having more than one surgery aiming tumor resection was associated with increased postoperative complications (p = 0.002). Incidence of complications were highest after extragonadal germ cell tumor (35%) and hepatic tumors (29%).

CONCLUSIONS

Postoperative complications of abdominal tumor surgery are diverse in children. They are related with prolonged hospital stay and need for medical or surgical interventions. Number of surgeries, organ of origin and tumor type have an influence on risk of complications.

Bilateral Renal Tumors in Children: The First 5 Years' Experience of National Centralization in The Netherlands and a Narrative Review of the Literature

Survival of unilateral Wilms tumors (WTs) is exceeding 90%, whereas bilateral WTs have an inferior outcome. We evaluated all Dutch patients with bilateral kidney tumors, treated in the first five years of national centralization and reviewed relevant literature. We identified 24 patients in our center (2015–2020), 23 patients had WT/nephroblastomatosis and one renal cell carcinoma. Patients were treated according to SIOP-RTSG protocols. Chemotherapy response was observed in 26/34 WTs. Nephroblastomatosis lesions were stable (n = 7) or showed response (n = 18). Nephron-sparing surgery was performed in 11/22 patients undergoing surgery (n = 2 kidneys positive margins). Local stage in 20 patients with ≥1 WT revealed stage I (n = 7), II (n = 4) and III (n = 9). Histology was intermediate risk in 15 patients and high risk in 5. Three patients developed a WT in a treated nephroblastomatosis lesion. Two of 24 patients died following toxicity and renal failure, i.e., respectively dialysis-related invasive fungal infection and septic shock. Genetic predisposition was confirmed in 18/24 patients. Our literature review revealed that knowledge is scarce on bilateral renal tumor patients with metastases and that radiotherapy seems important for local stage III patients. Bilateral renal tumors are a therapeutic challenge. We describe management and outcome in a national expert center and summarized available literature, serving as baseline for further improvement of care.

Nephron-sparing approach for familial bilateral synchronous Wilms tumors

Wilms tumors are the most common renal malignancy of childhood, often presenting as asymptomatic abdominal masses. These tumors can occur either in a unilateral or bilateral fashion, with bilateral tumors more commonly associated with various genetic syndromes and familial inheritance with some known loci. Bilateral tumors present challenges with regards to balancing oncologic control with renal function. Here, we present an unusual case of a young female patient diagnosed with bilateral Wilms tumors on the background of a strong family history and unknown genetic loci.

Evaluation of the nephron-sparing surgery formula in Wilms tumors

AIM

Definitions of nephron-sparing surgery (NSS) procedures in Wilms tumor (WT) are not clear. The new UMBRELLA protocol offers a formula (NSS(X)-SRM(n)-PRM(n)-RRP(n%)) to better define the different NSS parameters. We aimed to assess the advantages and limits of this new formula.

METHODS

This retrospective monocentric study included patients operated by NSS for WT from 1975 to 2018. We reviewed the medical records and applied the NSS formula to all included patients.

RESULTS

Eighty kidneys were operated on 56 patients at a mean age of 19.2 months (4 days-7.5 years), with 49 partial nephrectomies and 31 tumorectomies. The assessment of the surgical resection margins (SRM) showed a doubt in six cases and one tumor breach. An intact pseudocapsule along the resection margin with no renal parenchyma was found in four cases at pathological resection margins (PRM) assessment, whereas a tumor breach was described in seven cases. Among the six patients with a surgical doubt, only one had a pathological stage III. There were no surgical doubts in the seven patients with tumor breach at pathology. At a mean follow-up of eight years (15 days-28.6 years), eight patients had elevated blood pressure levels. Ten had proteinuria. These two parameters were significantly increased in patients with a remaining renal parenchyma (RRP) of less than half of the initial total renal parenchyma. The serum creatinine level was normal for all except two patients.

CONCLUSION

The new NSS formula described all the crucial elements of NSS. RRP seemed essential for the evaluation of long-term renal function.

Syndromic Wilms tumor: a review of predisposing conditions, surveillance and treatment

Predisposing syndromes associated with an increased risk of Wilms tumor (WT) are responsible for 9–17% of all cases of the malignancy. Due to an earlier age at WT diagnosis and an increased incidence of bilateral and metachronous disease, management of syndromic WT warrants a distinct approach from that of non-syndromic WT. This review of English-language manuscripts about WT focuses on the most common syndromes, surveillance protocols and current treatment strategies. Highlighted syndromes include those associated with WT1, such as WAGR (Wilms-Aniridia-Genitourinary-mental Retardation), Denys-Drash syndrome (DDS), and Frasier syndrome, 11p15 defects, such as Beckwith-Wiedemann syndrome (BWS), among others. General surveillance guidelines include screening renal or abdominal ultrasound every 3–4 months until the age of 5 or 7, depending on the syndrome. Further, some of the predisposing conditions also increase the risk of other malignancies, such as gonadoblastoma and hepatoblastoma. With promising results for nephron-sparing surgery in bilateral non-syndromic WT, there are increasing reports and recommendations to pursue nephron-sparing for these patients who are at greater risk of bilateral, metachronous lesions. In addition to the loss of renal parenchyma from malignancy, many patients are at risk of developing renal insufficiency as part of their syndrome. Although there may be some increase in the complication rate, recurrence free survival seems equivalent. Some conditions require specialized approaches to adjuvant therapy, as their syndrome may make them especially susceptible to side effects.

Early and late adverse renal effects after potentially nephrotoxic treatment for childhood cancer

BACKGROUND

Improvements in diagnostics and treatment for paediatric malignancies resulted in a major increase in survival. However, childhood cancer survivors (CCS) are at risk of developing adverse effects caused by multimodal treatment for their malignancy. Nephrotoxicity is a known side effect of several treatments, including cisplatin, carboplatin, ifosfamide, radiotherapy and nephrectomy, and can cause glomerular filtration rate (GFR) impairment, proteinuria, tubulopathy, and hypertension. Evidence about the long-term effects of these treatments on renal function remains inconclusive. It is important to know the risk of, and risk factors for, early and late adverse renal effects, so that ultimately treatment and screening protocols can be adjusted. This review is an update of a previously published Cochrane Review.

OBJECTIVES

To evaluate existing evidence on the effects of potentially nephrotoxic treatment modalities on the prevalence of renal dysfunction in survivors treated for childhood cancer with a median or mean survival of at least one year after cessation of treatment, where possible in comparison with the general population or CCS treated without potentially nephrotoxic treatment. In addition, to evaluate evidence on associated risk factors, such as follow-up duration, age at time of diagnosis and treatment combinations, as well as the effect of doses.

SEARCH METHODS

On 31 March 2017 we searched the following electronic databases: CENTRAL, MEDLINE and Embase. In addition, we screened reference lists of relevant studies and we searched the congress proceedings of the International Society of Pediatric Oncology (SIOP) and The American Society of Pediatric Hematology/Oncology (ASPHO) from 2010 to 2016/2017.

SELECTION CRITERIA

Except for case reports, case series and studies including fewer than 20 participants, we included studies with all study designs that reported on renal function (one year or longer after cessation of treatment), in CCS treated before the age of 21 years with cisplatin, carboplatin, ifosfamide, radiation involving the kidney region, a nephrectomy, or a combination of two or more of these treatments. When not all treatment modalities were described or the study group of interest was unclear, a study was not eligible for the evaluation of prevalence. We still included it for the assessment of risk factors if it had performed a multivariable analysis.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment and data extraction using standardised data collection forms. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Apart from the remaining 37 studies included from the original review, the search resulted in the inclusion of 24 new studies. In total, we included 61 studies; 46 for prevalence, six for both prevalence and risk factors, and nine not meeting the inclusion criteria, but assessing risk factors. The 52 studies evaluating the prevalence of renal dysfunction included 13,327 participants of interest, of whom at least 4499 underwent renal function testing. The prevalence of adverse renal effects ranged from 0% to 84%. This variation may be due to diversity of included malignancies, received treatments, reported outcome measures, follow-up duration and the methodological quality of available evidence.Seven out of 52 studies, including 244 participants, reported the prevalence of chronic kidney disease, which ranged from 2.4% to 32%.Of these 52 studies, 36 studied a decreased (estimated) GFR, including at least 432 CCS, and found it was present in 0% to 73.7% of participants. One eligible study reported an increased risk of glomerular dysfunction after concomitant treatment with aminoglycosides and vancomycin in CCS receiving total body irradiation (TBI). Four non-eligible studies assessing a total cohort of CCS, found nephrectomy and (high-dose (HD)) ifosfamide as risk factors for decreased GFR. The majority also reported cisplatin as a risk factor. In addition, two non-eligible studies showed an association of a longer follow-up period with glomerular dysfunction.Twenty-two out of 52 studies, including 851 participants, studied proteinuria, which was present in 3.5% to 84% of participants. Risk factors, analysed by three non-eligible studies, included HD cisplatin, (HD) ifosfamide, TBI, and a combination of nephrectomy and abdominal radiotherapy. However, studies were contradictory and incomparable.Eleven out of 52 studies assessed hypophosphataemia or tubular phosphate reabsorption (TPR), or both. Prevalence ranged between 0% and 36.8% for hypophosphataemia in 287 participants, and from 0% to 62.5% for impaired TPR in 246 participants. One non-eligible study investigated risk factors for hypophosphataemia, but could not find any association.Four out of 52 studies, including 128 CCS, assessed the prevalence of hypomagnesaemia, which ranged between 13.2% and 28.6%. Both non-eligible studies investigating risk factors identified cisplatin as a risk factor. Carboplatin, nephrectomy and follow-up time were other reported risk factors.The prevalence of hypertension ranged from 0% to 50% in 2464 participants (30/52 studies). Risk factors reported by one eligible study were older age at screening and abdominal radiotherapy. A non-eligible study also found long follow-up time as risk factor. Three non-eligible studies showed that a higher body mass index increased the risk of hypertension. Treatment-related risk factors were abdominal radiotherapy and TBI, but studies were inconsistent.Because of the profound heterogeneity of the studies, it was not possible to perform meta-analyses. Risk of bias was present in all studies.

AUTHORS' CONCLUSIONS

The prevalence of adverse renal effects after treatment with cisplatin, carboplatin, ifosfamide, radiation therapy involving the kidney region, nephrectomy, or any combination of these, ranged from 0% to 84% depending on the study population, received treatment combination, reported outcome measure, follow-up duration and methodological quality. With currently available evidence, it was not possible to draw solid conclusions regarding the prevalence of, and treatment-related risk factors for, specific adverse renal effects. Future studies should focus on adequate study designs and reporting, including large prospective cohort studies with adequate control groups when possible. In addition, these studies should deploy multivariable risk factor analyses to correct for possible confounding. Next to research concerning known nephrotoxic therapies, exploring nephrotoxicity after new therapeutic agents is advised for future studies. Until more evidence becomes available, CCS should preferably be enrolled into long-term follow-up programmes to monitor their renal function and blood pressure.

Clinical features, treatment, and outcomes of bilateral Wilms' tumor: A systematic review and meta-analysis

BACKGROUND

Wilms' tumor(WT) is the most common malignant renal tumor of childhood. Despite the good prognosis of WT, bilateral Wilms' tumor (BWT) still has a poor outcome. We systematically reviewed the literature on BWT, aiming to define its clinical features, treatment, and outcomes.

METHODS

PubMed, OVID EMbase, Web of Science, and Cochrane Library were systematically searched for studies published from 1980 to 2017. Case series and comparative studies reported clinical data of BWT patients were included.

RESULTS

A total of 32 studies comprising 1457 patients were retained for primary outcome. Hemihypertrophy, cryptorchidism, and Beckwith-Wiedemann syndrome(BWS) are the most common congenital anomalies and syndrome. 86% of patients had favorable histology (FH). Patients with local stage I or II accounted for 64%, and 12.6% had metastasis at diagnosis. Bilateral nephron-sparing surgery (NSS) was achieved in 33.8%. Recurrence and renal failure occurred in 20% and 8%. The overall survival (OS) was 73%. In comparative studies, OS of patients undergoing bilateral NSS was similar to that of other operation types.

CONCLUSION

Prognosis of BWT has been improved but is significantly poorer than WT. Bilateral NSS was recommended by most centers to preserve more renal volume. However, finding a balance between retaining renal function and avoiding recurrence remains a question.

TYPE OF STUDY

Systematic review.

LEVEL OF EVIDENCE

Level IV.

Management of Bilateral Wilms' Tumor: Our Experience

Management of bilateral Wilms' tumor is particularly challenging, considering the chances of recurrence and long-term renal function for affected patients. Aggressive surgical resection to prevent recurrence must be balanced with the desire to preserve renal function. We evaluated our experience in the management of bilateral Wilms' tumor stressing the challenges encountered in decision making and the role of nephron sparing surgery. We had four children presenting with bilateral Wilms' tumor. All of them were appropriately staged and given standard chemotherapy as per NWTS-5 guidelines. Tumors were considered to have a 'good' response to chemotherapy if sufficient tumor shrinkage was observed so that renal hilum was seen free of tumor and vice versa. Nephron-sparing surgery was considered in all and was performed when feasible, followed by completion adjuvant chemotherapy. All patients were followed up with serial ultrasound scans (3-6 monthly) and CECT abdomen (yearly once). Blood urea and serum creatinine, hypertension, and proteinuria were assessed during follow-up visits. All four children received neo-adjuvant chemotherapy as per NWTS-5 guidelines. The first child had poor response to chemotherapy and was considered for left radical and right partial nephrectomy. However, patient attenders refused any surgical intervention and the child was taken home. The second child had a 'good' response on left side and was planned for left partial and right radical nephroureterectomy based on pre-operative imaging analysis. However, intra-operatively, bilateral partial nephrectomy with good margins was feasible. The third child though, showed 'poor' response to pre-op chemotherapy and warranted bilateral nephroureterectomy, right partial and left radical nephroureterectomy was feasible. However, in the fourth child, we were not able to perform nephron sparing surgery and left nephroureterectomy with right tumor biopsy was done. Following this, child was started on 2nd-line chemotherapy, now awaiting right partial nephrectomy. The second child is on follow up for 1.5 years, doing well. However, the third child expired 1.5 years following surgery due to recurrence (lung metastasis). Management of bilateral Wilm's tumor is challenging and nephron-sparing surgery should be considered in all patients having bilateral Wilm's tumor with favorable histology, even if pre-operative imaging studies suggest that the lesions are unresectable.

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

OBJECTIVES

Wilms tumor is the most common renal cancer in children. Approximately 5% of children with Wilms tumor present with disease in both kidneys. The treatment challenge is to achieve a high cure rate while maintaining long-term renal function. We retrospectively reviewed our institutional experience with nephron sparing surgery (NSS) in patients with synchronous bilateral Wilms tumor (BWT) operated on between 2001 and 2014.

METHODS

Imaging studies, surgical approach, adjuvant therapy, and pathology reports were reviewed. Outcomes evaluated included surgical complications, tumor recurrence, patient survival, and renal function, as assessed by estimated glomerular filtration rate.

RESULTS

A total of 42 patients with BWT were identified: 39 (92.9%) patients underwent bilateral NSS; only 3 patients (7.1%) underwent unilateral nephrectomy with contralateral NSS. Postoperative complications included prolonged urine leak (10), infection (6), intussusception (2), and transient renal insufficiency (1). Three patients required early (within 4 months) repeat of NSS for residual tumor. In the long-term, 7 (16.7%) patients had local tumor recurrence (managed with repeat NSS in 6 and completion nephrectomy in 1) and 3 had an episode of intestinal obstruction requiring surgical intervention. Overall survival was 85.7% (mean follow-up, 4.1 years). Of the 6 patients who died, 5 had diffuse anaplastic histology. All of the patients had an estimated glomerular filtration rate more than 60 mL/min/1.73 m at the last follow-up; no patient developed end-stage renal disease.

CONCLUSIONS

In patients with synchronous, BWT, bilateral NSS is safe and almost always feasible, thereby preserving maximal renal parenchyma. With this approach, survival was excellent, as was maintenance of the renal function.

Management of bilateral Wilms tumor over three decades: The perspective of a single center

INTRODUCTION

Outcomes of Wilms tumor improved in last 50 years and excellent survival rates can be achieved especially in case of non-metastatic disease and favorable histology. Nevertheless, bilateral cases still stand as a therapeutic challenge. Prognosis of bilateral Wilms tumor (BWT) is not as good as the unilateral tumors of similar stage and histology in terms of survival and renal function.

OBJECTIVE

Management of BWT is constantly evolving and still stands as a therapeutic challenge. This study is designed to review and share our experiences on this topic from a surgical standpoint.

STUDY DESIGN

The records of patients treated in our clinic between 1980 and 2013 according to Turkish Pediatric Group of Oncology protocol were analyzed retrospectively and clinical data, surgical details, pathology results, long term outcomes were analyzed.

RESULTS

Thirteen girls and 7 boys with a mean age of 2,5 years were treated. There were 2 patients with Wilms tumor-Aniridia-Growth Retardation complex and one with isolated hemihypertrophy. Metastasis were detected in lungs of 4 patients; liver of 2 and in the cranium of one. All patients except one with the presumptive diagnosis of unilateral Wilms tumor were given preoperative chemotherapy. To sum up; 19 nephroureterectomies, 8 partial nephrectomies and 13 enucleations were performed to 36 kidneys without any major early or late postoperative complications. Pathologic results revealed positive surgical margins in 2 lesions with enucleation and in 2 with partial nephrectomies and anaplasia in 4 patients. Two patients were not operated due to parental disapproval. Two patients had the need of dialysis; one was anephric and the others' renal functions recovered over a year. Seven patients received radiotherapy for pulmonary metastasis, positive surgical margins or local recurrences. Overall, 13 patients survived and 7 died due to metastasis, recurrences, and complication of dialysis and refusal of surgical treatment. Survival among all patients was 65% and 72.2% among operated ones. Of the 7 patients with the partial nephrectomy, 2 died and 5 survived. Among enucleation group, 8 out of 10 survived and 2 died. Survival was slightly higher among enucleation group (80% vs 71.4%). Median time of follow-up for survivors of disease is 5.8 years (min: 6 months and max: 14 years).

DISCUSSION

Outcomes of BWT management have changed dramatically during the last few decades from only survival, to a long life expectancy without the need of renal replacement therapy owing to improvements in treatment options. We argue that positive surgical margins do not necessarily lead to local recurrence. For this reason it may be wiser to favor on more nephron sparing surgery than to achieve negative surgical margins. Adjuvant chemotherapy and radiotherapy may be adequate to prevent local recurrence. Also, survival did not differ significantly between different ways of nephron sparing surgeries, so it may be wiser to choose enucleation over partial nephrectomy which preserves more nephrons. Nephron-sparing surgery should have utmost importance despite the risk of positive margins. On the other hand, there is not enough data to interpret if positive surgical margins have role on distant metastases or not. Presence of metastasis and recurrence seems to be an important determinant of prognosis given the fact that none of the survivors had any metastasis or recurrence.

CONCLUSION

Nephron preservation should be the aim while taking positive surgical margin risk on nephron sparing surgery side relying on postoperative chemotherapy and carefully planned radiotherapy to avoid recurrence. However, there is significant diversity on the management BWT in different centers and a certain validated guideline or protocol to provide the optimal treatment is still lacking.

The initial experience with RENAL Nephrometry in children, adolescents, and young adults with renal tumors

BACKGROUND

No standardized manner exits to objectively compare renal tumor complexity in children and adolescents. However, the RENAL Nephrometry scoring system has been recently developed in adults and shown to predict tumor complexity and correlate with clinical outcomes. Thus, the study objective was to evaluate RENAL Nephrometry tumor score in a population of children, adolescents, and young adults and correlate it with tumor features and pathology.

METHODS

Patients at the study institution who underwent attempted renal tumor resection from 2002 to 2012, and had pre-operative imaging available for scoring were retrospectively reviewed. A Nephrometry score for each affected kidney was calculated separately by two blinded reviewers and the final score was based on consensus review. Tumor characteristics and oncologic outcomes were compared between the low-, moderate-, and high-complexity masses.

RESULTS

Sixty-five patients and 67 kidneys met study criteria. This included: 5 (7.5%) low-complexity, 11 (16.4%) moderate-complexity, and 51 (76.1%) high-complexity lesions. In comparing the clinical and pathologic features between groups, it was observed that less complex masses were observed in older patients, were more commonly managed with nephron-sparing surgery, and more often represented renal cell carcinoma (RCC) and other non-Wilms tumor pathology. No statistically significant correlation was observed between tumor complexity score and blood loss, operative time, transfusion requirement, positive margins or tumor rupture.

CONCLUSION

In general, renal lesions in this population are highly complex. In its current form, RENAL Nephrometry appears most useful in evaluating tumor complexity in RCC and masses in older children and adolescents.

Bilateral Wilms tumors treated according to the Japan Wilms Tumor Study Group protocol

BACKGROUND

The introduction of multimodal therapy has improved the survival rate of bilateral Wilms tumors (BWT); however, the results are still not satisfactory in terms of the renal preservation. To establish a new treatment strategy for BWT, we reviewed the results of the cases registered in the Japan Wilms Tumor Study Group (JWiTS).

PROCEDURE

This analysis concerned patients with synchronous BWT registered in the JWiTS between 1996 and 2011. In these patients, the management of BWT included initial tumor resection or biopsy followed by chemotherapy. The details of the treatments and outcomes were analyzed.

RESULTS

Among the 355 cases registered in the JWiTS database, 31 (8.7%) had BWT. They were 16 males and 15 females with a mean age of 15.5 months. Preoperative chemotherapy was performed in 24 cases. Bilateral nephron-sparing surgery (NSS) was achieved in 10 of 28 cases (36%). All of the cases were of favorable nephroblastoma without anaplasia, and a WT1 mutation was detected in 21 of the 27 cases (78%) examined. The 5-year overall survival was 92.6%; however, 10 children (40%) developed impaired renal function and three of them developed renal failure.

CONCLUSIONS

The long-term survival rates for patients with synchronous BWT have improved. However, more than half of patients receive nephrectomy. The protocol should be changed to improve the rate of preservation of the renal parenchyma. Preoperative chemotherapy should be performed to shrink the tumors in every case, and subsequent NSS should be carried out after a central imaging evaluation.

Nephron sparing surgery for unilateral non-syndromic wilms tumor

The initial therapy for most children with Wilms tumor is radical nephrectomy. Several centers, have explored the role of Nephron-sparing procedures in children with unilateral non-syndromic Wilms tumors. The primary motivation for this approach is concern about late occurrence of renal dysfunction after unilateral nephrectomy. We report our experience with NSS for unilateral non-syndromic Wilms tumor. We reviewed the records of nine children who underwent nephron sparing surgery for unilateral, nonsyndromic Wilms tumors at our Hospital between Jan 2000 through Jan 2012. All patients received preoperative chemotherapy with two drugs (vincristine, and dactinomycin) following which patients underwent tumor resection. Subsequent renal function was assessed by estimating the glomerular filtration rate using creatinine clearance and other measures of long-term renal function assessment included blood pressure evaluation and the need for antihypertensive medications. During the study period nine children with a mean age 19.66 ± 14.37 months at diagnosis and presenting with unilateral non-syndromic Wilms tumor underwent nephron sparing surgery. In all the nine children, the renal plane of resection showed a tumor-free margin. Post-operative serum creatinine repeated at the end of 3 months revealed maintenance of good renal function in all children. Nephron sparing surgery is a safe and effective option in the management of early stage unilateral non-syndromic Wilms tumor. It is oncologically safe and does not lead to decreased local tumor control. The function of the kidney remnant remains rather well.

Repeat nephron-sparing surgery for children with bilateral Wilms tumor

BACKGROUND

Renal insufficiency is a significant complication of Wilms tumor treatment in the 5% with bilateral disease. Nephron-sparing surgery (NSS) is recommended after neoadjuvant chemotherapy initially. However, the role of NSS in recurrent disease is unknown. We reviewed our experience to assess the feasibility and oncologic and functional outcomes of repeat NSS for children with recurrent disease.

METHODS

A retrospective review was performed of all children treated at our institution for bilateral, favorable histology (FH) Wilms tumor. Patients undergoing repeat NSS for locally recurrent disease were identified. The outcomes evaluated included tumor recurrence, renal function, and patient survival.

RESULTS

Since 2001, 36 children with bilateral FH Wilms tumor have been treated at our institution. Eight patients (22%) underwent repeat NSS for locally recurrent disease. Two patients had a second local recurrence and underwent a third NSS. Six patients are alive without disease (75%) with an average follow-up of 4.5years. Two patients have died, each with blastemal-predominant histology at repeat NSS. The surviving patients have normal renal function, although two patients require medical management of hypertension.

CONCLUSIONS

Our experience suggests that repeat NSS for local recurrence of FH bilateral Wilms tumor is feasible and affords acceptable oncologic outcome with preservation of renal function. However, more aggressive therapy may be required for patients whose recurrence has blastemal-predominant histology, given the poor outcome for these patients in our series.

Early and late renal adverse effects after potentially nephrotoxic treatment for childhood cancer

BACKGROUND

Great improvements in diagnostics and treatment for malignant disease in childhood have led to a major increase in survival. However, childhood cancer survivors (CCS) are at great risk for developing adverse effects caused by multimodal treatment for their malignancy. Nephrotoxicity is one of these known (acute) side effects of several treatments, including cisplatin, carboplatin, ifosfamide, radiotherapy and nephrectomy, and can cause glomerular filtration rate impairment, proteinuria, tubulopathy and hypertension. However, evidence about the long-term effects of these treatments on renal function remains inconclusive. To reduce the number of (long-term) nephrotoxic events in CCS, it is important to know the risk of, and risk factors for, early and late renal adverse effects, so that ultimately treatment and screening protocols can be adjusted.

OBJECTIVES

To evaluate existing evidence on the effects of potentially nephrotoxic treatment modalities on the prevalence of and associated risk factors for renal dysfunction in survivors treated for childhood cancer with a median or mean survival of at least one year after cessation of treatment, where possible in comparison with healthy controls or CCS treated without potentially nephrotoxic treatment.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4, 2011), MEDLINE/PubMed (from 1945 to December 2011) and EMBASE/Ovid (from 1980 to December 2011).

SELECTION CRITERIA

With the exception of case reports, case series and studies including fewer than 20 participants, we included studies with all study designs that reported on renal function (one year or longer after cessation of treatment) in children and adults who were treated for a paediatric malignancy (aged 18 years or younger at diagnosis) with cisplatin, carboplatin, ifosfamide, radiation including the kidney region and/or a nephrectomy.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction using standardised data collection forms. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

The search strategy identified 5504 studies, of which 5138 were excluded on the basis of title and/or abstract. The full-text screening of the remaining 366 articles resulted in the inclusion of 57 studies investigating the prevalence of and sometimes also risk factors for early and late renal adverse effects of treatment for childhood cancer. The 57 studies included at least 13,338 participants of interest for this study, of whom at least 6516 underwent renal function testing. The prevalence of renal adverse effects ranged from 0% to 84%. This variation may be due to diversity in included malignancies, prescribed treatments, reported outcome measurements and the methodological quality of available evidence.Chronic kidney disease/renal insufficiency (as defined by the authors of the original studies) was reported in 10 of 57 studies. The prevalence of chronic kidney disease ranged between 0.5% and 70.4% in the 10 studies and between 0.5% and 18.8% in the six studies that specifically investigated Wilms' tumour survivors treated with a unilateral nephrectomy.A decreased (estimated) glomerular filtration rate was present in 0% to 50% of all assessed survivors (32/57 studies). Total body irradiation; concomitant treatment with aminoglycosides, vancomycin, amphotericin B or cyclosporin A; older age at treatment and longer interval from therapy to follow-up were significant risk factors reported in multivariate analyses. Proteinuria was present in 0% to 84% of all survivors (17/57 studies). No study performed multivariate analysis to assess risk factors for proteinuria.Hypophosphataemia was assessed in seven studies. Reported prevalences ranged between 0% and 47.6%, but four of seven studies found a prevalence of 0%. No studies assessed risk factors for hypophosphataemia using multivariate analysis. The prevalence of impairment of tubular phosphate reabsorption was mostly higher (range 0% to 62.5%; 11/57 studies). Higher cumulative ifosfamide dose, concomitant cisplatin treatment, nephrectomy and longer follow-up duration were significant risk factors for impaired tubular phosphate reabsorption in multivariate analyses.Treatment with cisplatin and carboplatin was associated with a significantly lower serum magnesium level in multivariate analysis, and the prevalence of hypomagnesaemia ranged between 0% and 37.5% in the eight studies investigating serum magnesium.Hypertension was investigated in 24 of the 57 studies. Reported prevalences ranged from 0% to 18.2%. A higher body mass index was the only significant risk factor noted in more than one multivariate analysis. Other reported factors that significantly increased the risk of hypertension were use of total body irradiation, abdominal irradiation, acute kidney injury, unrelated or autologous stem cell donor type, growth hormone therapy and older age at screening. Previous infection with hepatitis C significantly decreased the risk of hypertension.Because of the profound heterogeneity of the studies, it was not possible to perform any meta-analysis.

AUTHORS' CONCLUSIONS

The prevalence of renal adverse events after treatment with cisplatin, carboplatin, ifosfamide, radiation therapy involving the kidney region and/or nephrectomy ranged from 0% to 84%. With currently available evidence, it was not possible to draw any conclusions with regard to prevalence of and risk factors for renal adverse effects. Future studies should focus on adequate study design and reporting and should deploy multivariate risk factor analysis to correct for possible confounding. Until more evidence becomes available, CCS should be enrolled into long-term follow-up programmes to monitor their renal function and blood pressure.

Margin status and tumor recurrence after nephron-sparing surgery for bilateral Wilms tumor

PURPOSE

Nephron-sparing surgery (NSS) has been advocated for patients with bilateral Wilms tumor (BWT). We sought to determine whether margin status impacted local tumor recurrence.

METHODS

A retrospective review of patients undergoing NSS for BWT from November 1999 to March 2009 at our institution in which local recurrence rates based on margin status were compared.

RESULTS

Of 21 patients, five (23.8%) had positive margins. These and 2 (9.5%) with focal anaplasia received flank XRT. Seven (33%) patients developed recurrent disease, a mean of 18.0 (range 1.3-39.9) months after NSS. Recurrence rates were similar in patients with positive and negative margins (1/5 [20%] vs 6/16 [37.5%]; p = 0.47). Hypertension occurred more frequently in patients who received XRT (57.1% vs 28.6%). At a median follow-up of 28.6 months (range 5.2-142.3), 19 patients are alive, without evidence of disease; one patient (with a positive margin at initial NSS) died of metastatic anaplastic WT and another died of a brain tumor. One patient, with multiple risk factors, developed renal failure.

CONCLUSIONS

In our experience, local recurrence rates after NSS were not affected by surgical margin status although all patients with positive margins received XRT. These results support the aggressive use of NSS for patients with BWT.

Bilateral Wilms tumors (WT) treated with the SIOP 93 protocol in France: epidemiological survey and patient outcome

BACKGROUND

The treatment of bilateral Wilms tumors (WT) requires multimodality therapy with individualized decision to ensure cure while preserving as much renal parenchyma as possible.

PROCEDURE

We analyzed the clinical records of 49 children with bilateral WT treated in France between 1993 and 2001, according to the SIOP-93 guidelines (individual treatment program: Treatment was continued as long as there was imaging evidence of tumor regression). Pathology reports, duration of preoperative chemotherapy and surgical records were also reviewed. Overall Survival (OS) and Event-Free Survival (EFS) rates were studied and relationships between possible prognostic factors and survival were assessed.

RESULTS

Imaging studies revealed bilateral involvement in 98% of the cases. Whatever the response to preoperative chemotherapy, the mean duration of neoadjuvant chemotherapy was 80 days (Q1-Q3: 47-89 days). Forty-eight children underwent nephron sparing surgery (NSS) at least for one kidney and 19 for both. Five-year EFS and OS rates were, respectively, 83.4 and 89.5%. Only the most advanced stages were shown to affect OS (P = 0.03). At study endpoint, end-stage renal disease (ESRD) was reported in seven children, associated with a predisposing phenotype in three.

CONCLUSIONS

Results of this study demonstrate a favorable outcome of patients with bilateral WT receiving an individual treatment program. With a tailored approach to treatment according to the tumor response, 77% of our patients were operated before the third month of preoperative chemotherapy. In spite of good survival, 14% of our patients have ESRD.

Management of Wilms' tumor: NWTS vs SIOP

With the availability of several protocols in the management of Wilms' tumor, there is dilemma in the minds of the treating oncologists or pediatric onco-surgeons as to whether the child should receive upfront chemotherapy or should be operated upon primarily. It is necessary for us to understand why do we follow either of the protocols, NWTS which follows the upfront surgery principle or the SIOP which follows the upfront chemotherapy principle in all stages of the disease. While deciding which protocol to follow, it is imperative to know the pros and cons of the treatment strategies and also to study the outcome patterns in both the treatment regimes which is what this article highlights. In an attempt to compare all the differences in both the major protocols, it was realized that most of our patients in the Indian scenario present with advanced disease and thus poorer outcomes if intensive and appropriate treatment strategies are not utilized. Hence, it is imperative that we should study our own patients through the Indian Wilms' tumor study group and adopt the policies which improve the overall event free survival on a nationwide basis.

Long-term outcome of bilateral Wilms tumors (BWT)

BACKGROUND

Modern WT management consist of ample chemotherapy, nephron-sparing surgery, and, when indicated, radiotherapy. Survivors may develop renal failure or secondary tumors due to anticancer treatment. We analyzed long-term outcome (follow-up >5 years) after bilateral Wilms tumor (BWT) treatment with respect to survival, renal function, and secondary malignancies.

METHODS

From 41 patients (23 females, 28 synchronous tumors) diagnosed with BWT between 1967 and 2007, 25 (18 females, 14 synchronous) with a follow-up >5 years could be included. Of this subgroup, median age at diagnosis was 1.64 years (range 0.27-5.35), and at maximum follow-up 14.99 years (range 5.40-33.99). Data were retrospectively collected and analyzed.

RESULTS

One patient (4%) died 17.75 years after diagnosis, five (20%) had renal transplants: 3/5 after bilateral nephrectomy for Denys-Drash syndrome (DDS), and 2/5 for ESRD after an interval of 7 and 18 years, respectively. All transplanted patients remained in CR. Another three patients developed mild renal insufficiency (creatinine levels 1.3, 1.8, and 2.8 mg/100 ml, respectively; N = 0.5-1.2), combined with hypertension in 1; neither of them was transplanted. Sixteen (64%) had normal renal function and were in CR. Long-term renal function appeared significantly better after bilateral nephron sparing surgery (NSS) then after other surgical procedures (P < 0.0001). Seven secondary tumors were found in five (20%) patients, one of whom had a DDS.

CONCLUSION

Long-term 10-year overall survival was 78%. There was significant morbidity (13/25, 52%), in terms of renal failure (8/25, 32%) including renal transplantation (5/25, 20%), and secondary tumors (5/25). These findings necessitate long-term follow-up beyond childhood. Future work should be directed at reducing the harmful effects of treatment, including the increased use of NSS.

Bilateral Wilms' tumors: single-center experience with 22 cases and literature review

OBJECTIVES

Bilateral Wilms' tumors represent a therapeutic challenge. The primary aim of management is eradication of the neoplasm and preservation of renal function. We present our experience in the management of such cases in a single-center experience.

METHODS

This was a retrospective study of 22 patients with histologically proven bilateral nephroblastoma who were treated from 1993 to 2008 at our center. Of the 22 patients, 12 were girls and 10 were boys, with a median age of 3 years (range 1-9); 19 had a synchronous presentation and 3 a metachronous presentation. Of the 22 patients, 6 underwent initial surgical resection followed by chemotherapy and 16 underwent initial biopsy and preoperative chemotherapy. The final oncologic and renal outcomes were assessed.

RESULTS

The median follow-up period was 3 years (range 1-11). Of the 22 patients, 8 died, for an overall survival rate of 63.5%. The survival for the initial chemotherapy and initial surgery groups was essentially similar. Of all the variables studied, unfavorable histologic findings had a significant negative effect on survival. Of the 5 patients with unfavorable histologic findings, 4 died during the follow-up period. The median volume of preserved renal parenchyma was 40%. All patients had good renal function during follow-up, except for 1 patient who had undergone bilateral nephrectomy.

CONCLUSIONS

Bilateral Wilms' tumors impose 2 conflicting issues: elimination of the pathology and preservation of the renal function. Currently, treatment regimens involving initial chemotherapy followed by conservative surgery can achieve these goals in an important proportion of patients.

Cold infusion for salvage partial hilar nephrectomy in patient with bilateral wilms tumor

We describe the use of an ice-cold solution of Ringer's lactate with additives to ameliorate ischemia-reperfusion injury and avoid renal failure in a child with bilateral Wilms tumor requiring nonanatomic, hilar resection that would leave the patient with marginal renal parenchyma postoperatively. The adequate renal function afforded by the procedure avoided the possible need for dialysis and allowed the resection area to be irradiated to prevent tumor recurrence before eventual renal transplantation.

Renal function outcomes in patients treated with nephron sparing surgery for bilateral Wilms tumor

PURPOSE

Management of bilateral Wilms tumor represents a particular challenge in the consideration of long-term renal function for affected patients. Aggressive surgical resection to prevent recurrence must be balanced with the desire to preserve renal function. We evaluated our institutional experience with nephrological outcomes in patients treated with nephron sparing surgery for bilateral Wilms tumor.

MATERIALS AND METHODS

We identified all patients with synchronous bilateral Wilms tumors presenting to St. Jude Children's Research Hospital between October 1987 and February 2004. We also included patients with Wilms tumor involving a solitary kidney presenting during the same period. A total of 17 patients were identified who underwent nephron sparing surgery, including 16 with bilateral tumors and 1 with tumor in a solitary kidney. Institutional review board approval was obtained to retrospectively review records and analyze outcomes based on long-term renal function, hypertension, proteinuria, need for dialysis and indications for renal transplantation.

RESULTS

Eight of the 17 patients initially underwent bilateral nephron sparing surgery and 9 initially underwent a combination of nephrectomy and contralateral nephron sparing surgery. Two patients were eventually rendered anephric following further resections secondary to local recurrence. Before the initiation of therapy all patients had normal baseline creatinine clearance, which was calculated using the Schwartz formula. At a median followup from diagnosis of 72 months (range 15 to 207) 1 patient had renal insufficiency and another 3 had renal failure requiring dialysis. One of the 3 patients on dialysis died of metastatic Wilms and 2 await renal transplantation. None of the remaining patients had evidence of proteinuria. Ten of the 17 patients (58.8%) had hypertension at diagnosis and 9 (52.9%) required antihypertensive medications at the most recent followup. The overall survival rate in this group of patients was 88.2% with no evidence of disease in survivors at the most recent followup.

CONCLUSIONS

When combined with adjuvant radiation and/or chemotherapy, nephron sparing surgery provides an opportunity to preserve renal function, while maintaining excellent long-term oncological outcomes for patients with bilateral Wilms tumor.