Characteristics and outcome of synchronous bilateral Wilms tumour in the SIOP WT 2001 Study: Report from the SIOP Renal Tumour Study Group (SIOP-RTSG).

BACKGROUND: Among patients with nephroblastoma, those with bilateral disease are a unique population where maximising tumour control must be balanced with preserving renal parenchyma. METHODS: The SIOP 2001 protocol recommended surgery after neoadjuvant cycle(s) of Dactinomycin and Vincristine (AV) with response-adapted intensification, if needed. Adjuvant treatment was given based on the lesion with the worst histology. RESULTS: Three hundred and twenty seven patients with stage V disease were evaluable: 174 had bilateral Wilms tumour (BWT), 101 unilateral WT and contralateral nephroblastomatosis (NB) and 52 bilateral nephroblastomatosis. In these three groups, the estimated 5y-EFS was 76.1%, 84.6%, and 74.9%, respectively. AV chemotherapy alone was the successful chemotherapy for 58.7% of all the patients and 65.6% of the non-metastatic patients. Among the 174 patients with BWT, 149 (88.2%) had at least one nephron-sparing surgery. Twenty of 61 bilateral stage I patients were treated with four-week AV postoperatively achieving 94.4% 5y-EFS. At last follow-up, 87% of patients had normal renal function. CONCLUSIONS: This study demonstrates that AV without anthracyclines is sufficient to achieve NSS and good survival in the majority of patients. For patients with bilateral stage I WT and intermediate risk histology, only four weeks adjuvant AV seems to be sufficient. CLINICAL TRIAL REGISTRATION: NCT00047138.

Sacrococcygeal teratoma: Long-term outcomes. A UK CCLG Surgeons Group Nationwide Study.

AIM: Sacrococcygeal teratoma (SCT) is a rare paediatric germ cell tumour (1:40,000). Long-term data regarding urinary tract and bowel function after SCT resection is limited to few studies. A UK Children's Cancer and Leukaemia Group (CCLG) Surgeons multicentre study aimed to critically analyse long-term functional outcomes in patients following resection of SCT. METHODS: Nationwide study of UK paediatric surgical oncology centres using a standardised data collection form. All index cases of newborn infants and children <16 years with SCT diagnosis during 2005-2015 were included. RESULTS: 165 SCT patients treated at 14 UK paediatric surgical oncology centres were included. Median age at presentation was 1 day [interquartile range, IQR: 0-25]; median age at surgery was 10 days [IQR: 4-150]. One hundred seventeen (70%) were female and 48 (30%) male. Antenatal diagnosis was made in 44% index cases. Total 59% of patients were Altman Stage I or II lesions. Follow-up data were available in 83% cases. Tumour recurrence occurred in 13 (7%) patients at median age 13 months [IQR: 8.75-30 months]. Fifty-nine (36%) of 165 patients had documented adverse bladder or bowel dysfunction. Twenty-two (37%) cases required urinary clean intermittent catheterisation (CIC) urology health care, with eight patients (14%) needing operative intervention to control management of bowel dysfunction. CONCLUSION: This UK CCLG study showed 36% of SCT patients develop bladder or bowel dysfunction after primary tumour resection. Functional assessment of bladder and bowel function is mandatory during after-care follow-up of all SCT patients. A multidisciplinary care pathway, with surgeon speciality groups including surgical oncology, paediatric urology and paediatric colorectal specialists, is strongly advised to facilitate 'best practice' monitoring of long-term health and improve patient quality of life (QoL) into adulthood.

Standardizing the surgical management of benign ovarian tumors in children and adolescents: A best practice Delphi consensus statement.

AIM: No widely agreed consensus protocols exist for the management of benign ovarian tumors (BOT) in children. This presents a substantial risk for suboptimal management. We aimed to generate multispecialty consensus guidance to standardize surgical management and provide a clear follow-up protocol for children with BOTs. METHODS: Prospective two-round confidential e-Delphi consensus survey distributed among multispecialty expert panel; concluded by two semistructured videoconferences. MAIN RESULTS: Consensus was generated on these core outcome sets: preoperative/intraoperative management; follow-up; adolescent gynecology referral. (1) Children with BOTs should receive the same management as other patients with potentially neoplastic lesions: Preoperative discussion at a pediatric oncology multidisciplinary meeting to risk stratify tumors, and management by health professionals with expertise in ovarian-sparing surgery and laparoscopy. (2) Ovarian-sparing surgery for BOTs should be performed wherever possible to maximize fertility preservation. (3) Ovarian masses detected during emergency laparoscopy/laparotomy should be left in situ wherever feasible and investigated appropriately (imaging/tumor markers) before resection. (4) Follow-up should be undertaken for all patients after BOT resection. Patients should be offered referral to adolescent gynecology to discuss fertility implications. CONCLUSION: This best practice Delphi consensus statement emphasizes the importance of managing children with BOTs through a well-defined oncological MDT strategy, in order to optimize risk stratification and allow fertility preservation by ovarian-sparing surgery wherever possible.

Extubation strategies after esophageal atresia repair.

BACKGROUND/PURPOSE: Early extubation following repair of esophageal atresia (EA) is desirable unless the anastomosis is under tension, in which case paralysis and post-operative ventilation may reduce the risk of anastomotic leakage. However, complications from emergency reintubations do occur with either strategy. We aim to examine the risk/benefit balance of early and delayed extubation following EA repair. METHODS: A seven-year retrospective review of all babies that underwent EA repair was performed. Babies extubated within 24 h of surgery were classified as early extubation (EE). Babies intubated beyond the first 24 h were classified as delayed extubation (DE). The EE group was subdivided into babies extubated in operating room (EIOR), and babies who returned to the neonatal intensive care unit (NICU) intubated but extubated within 24 h (EW24). RESULTS: Forty-six babies were analyzed, and overall 15 (32.6%) required 24 reintubation episodes. Eight (28.6%) babies in the EE group required reintubation. The EIOR group (n = 12) had significantly increased risk of requiring reintubation (OR:7, 95%CI:1.08 to 45.16:p = 0.04) compared to the EW24 group (n = 16). Seven (38.9%) babies in the DE group required reintubation. The complication rate from reintubation after EA repair was 17%. CONCLUSIONS: Extubation on the NICU within 24 h of surgery carried the lowest risk of reintubation. For babies with a tight anastomosis, elective postoperative ventilation appeared to confer a protective benefit without incurring a high risk of complications from reintubation.

Surgical management, staging, and outcomes of Wilms tumours with intravascular extension: Results of the IMPORT study.

PURPOSE: To review surgical management, tumour stage and clinical outcomes in children with intravascular extension of Wilms tumour (WT) registered in a national clinical study (2012-19). METHODS: WTs with presence/suspicion of tumour thrombus in the renal vein (RV) or beyond on radiology, surgery or pathology case report forms were identified. Only cases where thrombus was confirmed by surgeon and/or reference pathologist were included. Surgical management, disease stage, overall (OS) and event free survival (EFS) were investigated. RESULTS: 69/583 (11.8%) patients met the inclusion criteria. Forty-six (67%) had abdominal stage III due to thrombus-related reasons: 11 had macroscopically incomplete resection, including 8 cases where cavotomy was not performed; 20 had piecemeal complete resection of thrombus; 15 had microscopically positive resection margins at the RV. 66% of tumour thrombi contained viable tumour. There were eight relapses and five deaths. EFS, but not OS, was significantly associated with completeness of surgical resection (P<0.05). OS and EFS were also significantly associated with histological risk group (P<0.05) but not with viability of tumour thrombus (P=0.19; P=0.59). CONCLUSIONS: WTs with intravascular extension have a high risk of local stage III due to thrombus-related reasons. Controlled complete removal of the thrombus should be the aim of surgery. LEVEL OF EVIDENCE: Level II.

Management of pediatric benign ovarian tumors in England and Egypt: A comparative study.

AIM OF THE STUDY: We aimed to compare the management of pediatric benign ovarian tumors between an English center and three Egyptian institutions. MATERIALS AND METHODS: This was a retrospective review of all children presenting with benign ovarian tumors between January 2014 and January 2019. A standardized dataset was used to compare between both sides. RESULTS: Eighty-nine patients were included (54 English and 35 Egyptians). Median age at diagnosis in England was 13 years (2-16y), while in Egypt it was 7 years (9m-16y) with P =0.001. Mature teratomas or dermoid cysts were the most common findings in England and Egypt; 75.9% and 82.8% of cases, respectively. The presentation with an acute abdomen represented 27.8% of English and 28.6% of Egyptian patients. Incidentally diagnosed lesions constituted 15% of English patients, whereas none of the Egyptian cases were discovered incidentally. There were variations in diagnostic imaging; England: Ultrasound (USS) (54), magnetic resonance imaging (MRI) (37), and computed tomography (CT) (only one)-Egypt: USS (35), CT (17), and MRI (only one). Minimally invasive surgery (MIS) was performed in 15% of English and 23% of Egyptian patients (P = 0.334). Ovarian-sparing surgery (OSS) was performed in: England 35%, Egypt 37%; P = 0.851. OSS was performed using MIS in 87.5% (7/8) of English patients and 100% (8/8) of Egyptians. Patients presented as emergencies generally had open oophorectomies: England; 86.7% open and 80% oophorectomy-Egypt; 100% open and 90% oophorectomy. Recurrences or metachronous disease occurred in 5.6% of English and 5.7% of Egyptian patients. CONCLUSIONS: There were no significant differences regarding surgical management, tumor pathology, and recurrence or metachronous disease. However, age, incidental diagnosis, and imaging modalities showed notable differences. MIS was correlated with ovarian preservation, whereas emergency surgery generally resulted in open oophorectomy.

Optimal neoadjuvant chemotherapy duration in Wilms tumour with intravascular thrombus: A literature review and evidence from SIOP WT 2001 trial.

INTRODUCTION: Preoperative chemotherapy is recommended for children with Wilms tumour with intravascular extension. Extended chemotherapy may improve resectability, but increase tumour adherence to vascular endothelium, precluding complete resection. To evaluate the optimal length of preoperative treatment, we report a two-part review comprising systematic review of the literature and investigation of patients treated in the International Society of Paediatric Oncology (SIOP) WT 2001 trial. METHODS: Studies were identified using Medline and Embase databases from 1996 to present. English language titles reporting management of intravascular Wilms tumour were analysed. Patients with Wilms tumour and thrombus were identified from the SIOP WT 2001 trial. Overall survival (OS) and event-free survival (EFS), tumour regression, completeness of resection and cavectomy were investigated. RESULTS: The search retrieved 43 articles documenting 498 children. Note that 72% of the patients received neoadjuvant chemotherapy: 101 received standard course (4-6 weeks, standard course neoadjuvant chemotherapy [StC]) and 62 extended course (> 6 weeks, extended course neoadjuvant chemotherapy [EC]). There was no significant difference between the groups in terms of thrombus regression or completeness of resection. EFS was greater in the StC group (78 vs 54%; P = .04). Of 4511 patients registered in the SIOP WT 2001 trial, 166 had thrombus. Note that 97% of the patients received neoadjuvant chemotherapy: 63 StC and 67 EC. There was no significant difference between the groups with regard to tumour regression, complete resection, or cavectomy. Survival was significantly higher in those receiving StC than EC (OS: 95% vs 82%, P = .025; EFS: 88% vs 72%, P = .047). CONCLUSION: There is no evidence that prolonged courses of neoadjuvant chemotherapy beyond the recommended protocols confer any additional benefit in treating intravascular extension of Wilms tumour.

Testicular-sparing surgery in the pediatric population: multicenter review of practice with review of the literature.

PURPOSE OF REVIEW: Pediatric testicular tumors have predominantly favorable histology, which may permit testicular sparing surgery (TSS). Limited guidance exists for TSS in adults and is absent in pediatric practice.The international survey and retrospective case series evaluated the current use of TSS in pediatric testicular tumors. Alongside the complementary literature review, the aim of this work was to provide evidence that could be used to produce a guideline document. RECENT FINDINGS: Published evidence advocates small mass size as an indicator for TSS, this was not supported in the pediatric literature. Frozen section examination at TSS was not always performed by surgeons and yet the literature reports close to 100% specificity. Tumor markers and ultrasound findings are also used as indicators for TSS, a finding reflected in our survey results. SUMMARY: Multiple case series are reported but no large data series exists, which will require international collaboration rather than a drive to publish the results of individual centers. Common indicators for TSS use; such as tumor markers and imaging are known but further work needs to evaluate the role of on-table histology and the risks of this not being available.

Evaluation of needle biopsy as a potential risk factor for local recurrence of Wilms tumour in the SIOP WT 2001 trial.

RATIONALE: The impact of biopsying Wilms tumour (WT) at diagnosis on assigning the tumour stage and recommended treatment remains controversial. To address this important question, we analysed the potential association of all types of biopsy with local recurrence in patients treated in the SIOP WT 2001 trial, where needle biopsy was permitted without 'upstaging' the tumour to stage III. Only open biopsy required treatment as stage III. METHODS: Among 2971 patients with unilateral WT (stages I-IV), 420 relapsed (139 local). Risk factors for recurrence were analysed by Cox proportional hazard methods. RESULTS: Biopsy was performed in 969 of 2971 (33%) patients (64% cutting needle, 30% fine needle aspiration [FNA] and 6% open biopsy). Biopsied patients were older, with larger tumours and a greater proportion with high-risk histology. In multivariate analysis that included all factors associated with local recurrence in univariate analysis, only high-risk histology (hazard ratio [HR] = 2.32; 95% confidence interval [CI]: 1.58-3.42, p=<0.0001), age≥2 years (HR = 2.24; 95% CI: 1.22-4.09, p = 0.01) and preoperative tumour volume (HR = 1.07 per 100 ml; 95% CI: 1.02-1.12, p = 0.01) were significant. The HR for the association of local recurrence and event-free and overall survival with biopsy was not significant (HR = 1.4; 95% CI: 0.9-2.17, p = 0.13; HR = 1.1; 95% CI: 0.85-1.42, p = 0.46 and HR = 1.13; 95% CI: 0.79-1.62, p = 0.51, respectively). These results were not materially different whether FNA or open biopsy were included in the biopsy group or not. CONCLUSIONS: This post hoc analysis provides some reassurance that needle biopsy is not an independent adverse factor for either local recurrence or survival after adjustment for all relevant risk factors. Needle biopsy should not be an automatic criterion to 'upstage' WT.

The diagnostic accuracy and clinical utility of pediatric renal tumor biopsy: Report of the UK experience in the SIOP UK WT 2001 trial.

INTRODUCTION: The International Society of Paediatric Oncology (SIOP) protocols recommend preoperative chemotherapy appropriate for Wilms tumors (WTs) in children with renal tumors aged ≥6 months, reserving biopsy for "atypical" cases. The Children's Cancer and Leukaemia Group (CCLG) joined the SIOP-WT-2001 study but continued the national practice of biopsy at presentation. METHOD: Retrospective study of concordance between locally reported renal tumor biopsies and central pathology review nephrectomy diagnoses of children enrolled by CCLG centers in the SIOP-WT-2001 study. RESULTS: Biopsy reports were available for 552/787 children with unilateral tumors. 36 of 552 (6.5%) were nondiagnostic: 2 normal tissue, 12 necrotic, 9 insufficient sample, and 13 indeterminate results (disproportionately non-WTs). The sensitivity and specificity of biopsy to identify tumors that did not require SIOP empirical preoperative chemotherapy were 86.0% and 99.6%, respectively. 13 of 548 (2.4%) biopsy results were discordant with nephrectomy; non-WTs other than renal cell carcinoma and clear cell sarcoma of the kidney (CCSK) were poorly recognized. In children aged 6-119 months, 480 of 518 (91.6%) had WT or nephroblastomatosis. 5 of 518 (1%) had benign tumors, and only one diagnosed on biopsy. Biopsy results correctly changed clinical management in 25 of 518 (4.8%), including identifying 19 of 20 CCSKs, but would have led to overtreatment in 5 of 518 (1%) or undertreatment in 4 of 518 (0.8%). In children aged ≥10 years, biopsy correctly changed management in 5 of 19 (26%) cases with no discordance. CONCLUSION: Biopsy is less effective at identifying non-WTs than WTs and rarely changes management in younger children. Biopsy should be reserved in SIOP protocols for children ≥10 years and in younger children with clinical or radiological features inconsistent with WT.

Prevention of perioperative venous thromboembolism in pediatric patients: Guidelines from the Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI).

The Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) Guidelines Working Group on Thromboprophylaxis in Children has reviewed the literature and where possible provided advice on the care of children in the perioperative period. Areas reviewed include the incidence of perioperative venous thromboembolism (VTE), risk factors, evidence for mechanical and chemical prophylaxis, and complications. Safe practice of regional anesthesia with anticoagulant prophylaxis is detailed. In summary, there are few areas of strong evidence. Routine prophylaxis cannot be recommended for young children. Postpubertal adolescents (approximately 13 years and over) are at a slightly increased risk of VTE and should be assessed for prophylaxis and may warrant intervention if other risk factors are present. However, the incidence of VTE is significantly lower than in the adult population. This special interest review presents a summary and discussion of the key recommendations, a decision-making algorithm and a risk assessment chart. For the full guideline, go to www.apagbi.org.uk/publications/apa-guidelines.

Implications of a negative abdominal CT in the management of pediatric blunt abdominal trauma.

BACKGROUND: No consensus exists on management of children with a negative trauma CT following blunt abdominal trauma (BAT). Asymptomatic children are frequently "admitted for observation" following negative CT owing to concerns about missing an intraabdominal injury (IAI) without evidence for this practice. We aimed to investigate the feasibility of discharge following a negative CT scan in children sustaining blunt abdominal trauma. METHODS: Retrospective audit at a UK paediatric major trauma center and review of the literature. RESULTS: 108 patients were included (median age 11y; 60% male). Commonest mechanisms of injury: road traffic collisions (61 patients; 56%) and falls from a height (37; 34%). 40 (37%) had a normal CT scan, of whom 6 (15%) were discharged from ED. The remaining 34 patients were admitted, of whom 14 (41%) were discharged within 24h. The other 20 children were admitted for other specialty input. None of the 108 children had a missed IAI or reattended with suspicion of IAI. The NPV for CT to detect IAI was 100% (95% CI: 96%-100%). The literature search identified 3 observational cohort studies and 2 patient groups contained in a systematic review (total of 9149 patients with normal CT abdomen after BAT). Only 9 (<0.1%) patients required operative intervention for missed IAI. The NPV for CT to detect IAI was 99.6%-99.8% (95% CI 99%-100%). CONCLUSION: Our study and literature review demonstrate that asymptomatic children with a normal abdominal CT scan in the ED are very unlikely to have IAI and that the NPV of CT is very high (96%-100%). Direct discharge from the ED is possible for asymptomatic children with a negative CT following blunt abdominal trauma, as long as no other reasons for admission exist and should be accompanied by safety-net advice. LEVEL OF EVIDENCE STATEMENT: This is a level II evidence study. In itself it is a retrospective study, with the literature review including one large, high-quality prospective cohort study, and further prospective cohort studies of ordinary quality.

Improving outcomes in pilonidal sinus disease.

BACKGROUND: Optimal surgical treatment for pilonidal sinus disease remains controversial. Studies in children are uncommon with overall high postoperative recurrence and infection rates (20%). Our unit adopted a technique for excision of the pilonidal sinus with primary midline closure using a full-thickness flap. We present our results of this technique in the pediatric age group. METHODS: Single-center retrospective review and telephone follow-up was performed, including all children undergoing pilonidal sinus excision from 2005 to 2014 using the same operative technique and preoperative/postoperative care. RESULTS: 19 children were identified. Median age was 15years, and 47% were male. All had previously infected sinuses, with 5 requiring abscess drainage. Median follow-up was 13months (3.5-67months). Histology confirmed pilonidal sinus in 18/19 cases (one developmental malformation excluded from subsequent analysis). Recurrence requiring further surgery occurred in 4/18 (22%) patients at a median of 9months (range 8-36), wound dehiscence in 8/18 (44%), and wound infection in 5/18 (28%) cases. Laser hair removal of the natal cleft was performed in 7/18 (39%) patients with no further recurrence. CONCLUSION: This is the first report of this technique in children which showed a higher incidence of complications than a comparable adult study. Our study underlines the importance of accurate long-term outcomes when introducing new techniques to evaluate operation-associated morbidity. Our preliminary results of laser hair removal are promising but need to be evaluated with a prospective study.

Minimally invasive nephrectomy for Wilms tumors in children - data from SIOP 2001.

PURPOSE: To analyse the surgical and oncological outcome of minimally invasive surgery (MIS) for tumor nephrectomy in Wilms tumor (WT) patients. METHODS: WT patients from the SIOP 2001 trial, undergoing MIS for tumor nephrectomy were analyzed with regard to demographic characterization, surgical specifications, complications, and outcome. RESULTS: There were 24 children matching the inclusion criteria. Median age at operation was 40.35 months (14.3-65.4). All patients received preoperative chemotherapy. Median tumor volume was 177.5 ml at diagnosis (46.5-958) and 73.0 ml at surgery (3.8-776). There was one surgical complication (splenic injury), no intraoperative tumor rupture occurred. Abdominal stage was I in 14, II in 7, and III in 3 patients. Adequate lymph node sampling was performed in only 2 patients. One local relapse occurred. Event-free survival was 23/24, overall survival was 24/24, median follow up was 47 months (2-114). CONCLUSIONS: We present the largest series so far of minimally invasive nephrectomies for nephroblastoma based on a multinational trial. Treatment results were comparable to those of open surgery; however, experience of operating surgeons was generally high. Discipline of lymph node sampling was inadequate. Based on this analysis a prospective study on MIS in nephroblastoma is planned by the SIOP Renal Tumor Study Group.

Nephron sparing surgery (NSS) for unilateral wilms tumor (UWT): the SIOP 2001 experience.

BACKGROUND: Total nephrectomy (TN) remains the standard treatment of unilateral Wilms tumors (uWT). The SIOP WT-2001 protocol allowed Nephron Sparing Surgery (NSS) for polar or peripherally non-infiltrating tumors. AIM: Inventory of the current SIOP NSS-experience. PROCEDURES: 2,800 patients with a unilateral, localized or metastatic and an unequivocal surgical technique recorded were included. All had neo-adjuvant chemotherapy and delayed surgery. In 91 (3%) NSS was performed and in 2709 TN. Data was retrieved from the SIOP WT 2001 database. RESULTS: NSS group contained 65% stage I tumours and the TN group 48%. Tumor volume (at diagnosis and surgery) was significantly smaller in the NSS group. Within stage III, after NSS, 7/12 (58%) had positive margins (M +), 5 with tumor negative lymph nodes (LN-). After TN, 355/712 (55%) had M + , 182 were LN-. Treatment of M+ in the NSS group resulted in two conversions to TN (one combined with radiotherapy), three patients had radiotherapy only and in two patients local therapy, if given, was not recorded. After NSS, four recurrences occurred. For localized disease the 5-year overall (OS) and event free survival (EFS) in NSS group was 100 and 94.8 (95% CI:89.9-99.9), respectively, while OS and EFS in the TN group were 94.4 (95% CI: 93.2-95.5, log-rank test P = 0.06) and 86.5 (95% CI:85.0-88.1, log-rank test P = 0.06), respectively. CONCLUSIONS: NSS was only performed in 3% of patients with uWT. Despite excellent survival with few relapses, the gain of nephrons needs to be weighed against the risk to induce stage III with intensified therapy.

Surgical complications after immediate nephrectomy versus preoperative chemotherapy in non-metastatic Wilms' tumour: findings from the 1991-2001 United Kingdom Children's Cancer Study Group UKW3 Trial.

PURPOSE: To compare surgical complication rates after immediate nephrectomy versus delayed nephrectomy following preoperative chemotherapy in children with non-metastatic Wilms' tumour enrolled in UKW3, both in randomised patients and in those for whom the treatment approach was defined by parental or physician choice. METHODS: Records for all patients enrolled into UKW3 were reviewed. Any record of tumour rupture or surgical complication was extracted and comparisons made between the two treatment strategies in both populations of randomised and non-randomised patients. RESULTS: Of 525 children enrolled, 205 patients were randomised to either immediate nephrectomy (n=103) or pre-operative chemotherapy followed by delayed nephrectomy (n=102). Of the 320 children not randomised, data were available on 189 cases treated with immediate nephrectomy and 103 treated with pre-operative chemotherapy. There were significantly fewer surgical complications in randomised children given pre-operative chemotherapy before surgery compared to children undergoing immediate nephrectomy (1% vs. 20.4%, P<0.001); this difference was most marked for tumour rupture (0% vs. 14.6%, P<0.001). CONCLUSIONS: Delayed nephrectomy for Wilms' tumour, preceded by pre-operative chemotherapy was associated with fewer surgical complications compared with immediate nephrectomy.

Mesoblastic nephroma: a report of the United Kingdom Children's Cancer and Leukaemia Group (CCLG).

BACKGROUND: Mesoblastic nephroma (MN) is a rare tumour which occurs mainly in early infancy and for which primary nephrectomy is the treatment of choice. This study aimed to assess surgical complications and outcomes in this patient group and to re-evaluate the age threshold of 6 months for recommending primary nephrectomy. PROCEDURE: A retrospective file review of all cases of MN registered in UK Children's Cancer and Leukaemia Group renal tumour trials between October 1991 and March 2008. Data from the trials were compared with data held by the National Registry of Childhood Tumours, Oxford. RESULTS: Forty-seven (3.5%) confirmed cases of MN were found among 1346 registered renal tumours. Median age at diagnosis was 30 days (range birth-3.8 years). MN was significantly more common in the first 3 months of life compared to between 3 and 6 months (33 vs. 2 cases). Seven cases occurred between 6 months and 1 year and only five cases occurred beyond 1 year of age. There was a significant difference in the age of diagnosis by histological subtype. There were 11 complications in the series; no registered patient developed a recurrent tumour; and all were alive at last follow-up. CONCLUSIONS: Outcome for children with MN is excellent at all ages, with little indication for adjuvant chemotherapy. Children presenting at <3 months of age, should be treated by primary nephrectomy. In those presenting aged >3 months, alternative diagnoses should be considered, especially in the presence of surgical risk factors.