Nephron sparing surgery and surgical management of intravascular extension of Wilms tumor

Although general treatment approaches for Wilms tumor differ between Children's Oncology Group and Société Internationale d'Oncologie Pédiatrique-Renal Tumors Study Group protocols, complex tumors that may be candidates for nephron sparing surgery (NSS) and those with intravascular tumor extension represent a management challenge. In both of these scenarios, anatomic considerations are important in guiding management, making these areas of significant similarities in management between the international groups. This paper aims to explore the current approaches to NSS and intravascular tumor extension by both international groups, with attention to the evidence supporting these approaches and current knowledge gaps.

Surgical management of extremity rhabdomyosarcoma: A consensus opinion from the Children's Oncology Group, the European Pediatric Soft-Tissue Sarcoma Study Group, and the Cooperative Weichteilsarkom Studiengruppe

The treatment of extremity rhabdomyosarcoma remains a challenge due to several adverse prognostic factors frequently associated with this tumor site. The International Soft-Tissue Sarcoma Database Consortium (INSTRuCT) is a collaboration of the Children's Oncology Group Soft-Tissue Sarcoma Committee, the European Pediatric Soft-Tissue Sarcoma Study Group, and the Cooperative Weichteilsarkom Studiengruppe. The INSTRuCT surgical committee developed an internationally applicable consensus opinion document for the surgical treatment of extremity rhabdomyosarcoma. This document addresses surgical management, including biopsy, nodal staging, timing of therapy, resection and reexcision, reconstruction, and surgical approach at relapse.

International Comparisons of Clinical Demographics and Outcomes in the International Society of Pediatric Oncology Wilms Tumor 2001 Trial and Study

International comparisons of patient demographics, tumor characteristics, and survival can shed light on areas for health care system improvement. The International Society of Pediatric Oncology Wilms Tumor 2001 trial/study registered patients through national clinical study groups in Western Europe and Brazil. This retrospective post hoc analysis of the International Society of Pediatric Oncology Wilms Tumor 2001 database aims to make visible and suggest reasons for any variations in outcomes.

International variation in Wilms tumor survival parallels disease burden at diagnosis.

Outcome of SIOP patients with low- or intermediate-risk Wilms tumour relapsing after initial vincristine and actinomycin-D therapy only - the SIOP 93-01 and 2001 protocols

PURPOSE

Society of International Pediatric Oncology - Renal Tumor Study Group (SIOP-RTSG) treatment recommendations for relapsed Wilms tumour (WT) are stratified by the intensity of first-line treatment. To explore the evidence for the treatment of patients relapsing after vincristine and actinomycin-D (VA) treatment for primary WT, we retrospectively evaluated rescue treatment and survival of this patient group.

PATIENTS AND METHODS

We included 109 patients with relapse after VA therapy (no radiotherapy) for stage I-II primary low- or intermediate-risk WT from the SIOP 93-01 and SIOP 2001 studies. Univariate Cox regression analysis was performed to study the effect of relapse treatment intensity on event-free survival (EFS) and overall survival (OS). Relapse treatment intensity was classified into vincristine, actinomycin-D, and either doxorubicin or epirubicin (VAD), and more intensive therapies (ifosfamide/carboplatin/etoposide [ICE]/≥ 4 drugs/high-dose chemotherapy with haematopoietic stem cell transplantation [HD HSCT]).

RESULTS

Relapse treatment regimens included either VAD, or cyclophosphamide/carboplatin/etoposide/doxorubicin (CyCED), or ICE backbones. Radiotherapy was administered in 62 patients and HD HSCT in 15 patients. Overall, 5-year EFS and OS after relapse were 72.3% (95% confidence interval [CI]: 64.0-81.6%) and 79.3% (95% CI: 71.5-88.0%), respectively. Patients treated with VAD did not fare worse when compared with patients treated with more intensive therapies (hazard ratio EFS: 0.611 [95% CI: 0.228-1.638] [p-value = 0.327] and hazard ratio OS: 0.438 [95% CI: 0.126-1.700] [p-value = 0.193]).

CONCLUSION

Patients with relapsed WT after initial VA-only treatment showed no inferior EFS and OS when treated with VAD regimens compared with more intensive rescue regimens. A subset of patients relapsing after VA may benefit from less intensive rescue treatment than ICE/CyCED-based regimens and deserve to be pinpointed by identifying additional (molecular) prognostic factors in future studies.

Pleuropulmonary blastoma in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Pleuropulmonary blastoma (PPB) is a rare cancer occurring mainly during early childhood and often associated with germline DICER1 mutations. It is classified by the macroscopic appearance into three interrelated clinico-pathologic entities on a developmental continuum. Complete tumor resection is a main prognostic factor and can be performed at diagnosis or after neoadjuvant treatment that includes chemotherapy and in some cases radiotherapy. Optimal modalities of neo- or adjuvant treatments can be challenging taking into account potential long-term toxicities in this young population. This paper presents the recommendations for diagnosis and treatment of children and adolescents with PPB elaborated by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the European Union-funded project PARTNER (Paediatric Rare Tumours Network - European Registry).

Characteristics and outcome of pediatric renal cell carcinoma patients registered in the International Society of Pediatric Oncology (SIOP) 93-01, 2001 and UK-IMPORT database: A report of the SIOP-Renal Tumor Study Group

In children, renal cell carcinoma (RCC) is rare. This study is the first report of pediatric patients with RCC registered by the International Society of Pediatric Oncology-Renal Tumor Study Group (SIOP-RTSG). Pediatric patients with histologically confirmed RCC, registered in SIOP 93-01, 2001 and UK-IMPORT databases, were included. Event-free survival (EFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Between 1993 and 2019, 122 pediatric patients with RCC were registered. Available detailed data (n = 111) revealed 56 localized, 30 regionally advanced, 25 metastatic and no bilateral cases. Histological classification according to World Health Organization 2004, including immunohistochemical and molecular testing for transcription factor E3 (TFE3) and/or EB (TFEB) translocation, was available for 65/122 patients. In this group, the most common histological subtypes were translocation type RCC (MiT-RCC) (36/64, 56.3%), papillary type (19/64, 29.7%) and clear cell type (4/64, 6.3%). One histological subtype was not reported. In the remaining 57 patients, translocation testing could not be performed, or TFE-cytogenetics and/or immunohistochemistry results were missing. In this group, the most common RCC histological subtypes were papillary type (21/47, 44.7%) and clear cell type (11/47, 23.4%). Ten histological subtypes were not reported. Estimated 5-year (5y) EFS and 5y OS of the total group was 70.5% (95% CI = 61.7%-80.6%) and 84.5% (95% CI = 77.5%-92.2%), respectively. Estimated 5y OS for localized, regionally advanced, and metastatic disease was 96.8%, 92.3%, and 45.6%, respectively. In conclusion, the registered pediatric patients with RCC showed a reasonable outcome. Survival was substantially lower for patients with metastatic disease. This descriptive study stresses the importance of full, prospective registration including TFE-testing.

The European Paediatric Rare Tumours Network - European Registry (PARTNER) project for very rare tumors in children

The PARTNER project (Paediatric Rare Tumours Network - European Registry) was launched in 2016. PARTNER aims to create a European Registry dedicated to children and adolescents with very rare tumors (VRT). It links existing national registries and provides a registry for those countries in which a VRT registry has not yet been created. This consortium is composed of the various national cooperative groups and their respective member institutions. The strategic value of this project is based on the Europe-wide data collection concerning the treatment of VRTs. These data are provided to experts and constitute the basis for new clinical practice guidelines for use by ERN (European Reference Network) and non-ERN institutions. The proposed tasks and milestones will increase collaboration in the field of pediatric oncology among member states and will also facilitate the inclusion of low health expenditure average rate (LHEAR) countries in this process. In addition, this project creates a platform for VRTs that may represent a model on how to elaborate a comprehensive approach (case registration, international case consultation and treatment recommendations, and website to provide information for parents/patients) for rare diseases.

Pancreatoblastoma in children: EXPeRT/PARTNER diagnostic and therapeutic recommendations

Pancreatoblastoma (PBL) is a rare malignant epithelial neoplasm that affects typically young children. Signs related to advanced upper-abdominal tumor accompanied by elevated serum α-fetoprotein levels in a young child suggest PBL, however histopathological confirmation is mandatory. The mainstay of the treatment is a complete surgical resection. Unresectable and/or metastatic PBL may become amenable to complete delayed surgery after neoadjuvant chemotherapy. This manuscript presents the international consensus recommendations for the diagnosis and treatment of children with PBL, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the EU-funded PARTNER (Paediatric Rare Tumors Network - European Registry) project.

Consensus recommendations from the EXPeRT/PARTNER groups for the diagnosis and therapy of sex cord stromal tumors in children and adolescents

As part of the European Union-funded project designated Paediatric Rare Tumours Network - European Registry (PARTNER), the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) is continuously developing consensus recommendations in order to harmonize standard care for very rare solid tumors of children and adolescents. This paper presents the internationally recognized recommendations for the diagnosis and treatment of sex cord stromal tumors (SCST). The clinical approach to sex cord stromal tumors of the testis (TSCST) and ovary (OSCST) depends on histological differentiation and tumor stage. Virtually all TSCSTs present as localized nonmetastatic tumors, with excellent prognosis after complete resection. In contrast, the prognosis of OSCSTs may be adversely affected by tumor spillage during surgery or presence of metastases. In these cases, cisplatin-based chemotherapy is recommended. Of note, some SCSTs may develop in the context of tumor predisposition syndromes, for example, DICER-1, so that specific follow-up is indicated. SCSTs should be diagnosed and treated according to standardized recommendations that include reference pathology, genetic testing for tumor predisposition syndromes in selected cases, and stratified adjuvant chemotherapy in patients with unfavorable risk profile. To ensure high quality of diagnosis and therapy, patients should be enrolled into prospective registries.

Cutaneous melanoma in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Cutaneous melanoma is rare in children and, like other very rare pediatric tumors, it suffers from a shortage of knowledge and clinical expertise. The clinical management of pediatric melanoma is often challenging. Its clinical and pathological diagnosis may be difficult, and there is no standard treatment. In the absence of specific treatment guidelines, young patients are generally treated following the same principle as for adults, but concern remains about their access to clinical trials and new drugs, which have been shown to dramatically change the natural history of advanced melanoma. This paper presents the internationally recognized recommendations for the diagnosis and treatment of children and adolescents with cutaneous melanoma, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the EU-funded project called PARTNER (Paediatric Rare Tumours Network - European Registry). Main recommendations for melanoma are to discuss pediatric patients in multidisciplinary teams that include both pediatric oncologists and specialists in adult melanoma; to enroll patients in prospective trials, if available; to collect data in national-international databases; and to develop an effective international collaboration between pediatric and adult melanoma groups in order to facilitate the transfer of potentially effective new agents from the adult to the pediatric setting.

Adrenocortical tumours in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Adrenocortical tumours (ACTs) are rare during childhood. A complete surgical resection provides the best chance of cure, but the role and efficacy of the adjuvant therapy are still controversial. Various histologic criteria of malignancy for ACTs adopted in children do not facilitate comparative studies and are not completely shared. Therefore, a sharp demarcation between benign and malignant lesions has not been recognised, making it difficult to identify who potentially needs perioperative therapy. This manuscript presents the internationally harmonised recommendations for the diagnosis and treatment of ACTs in children and adolescents, established by the European Cooperative Study Group for Paediatric Rare Tumours (EXPeRT) group within the EU-funded project PARTNER (Paediatric Rare Tumours Network - European Registry).

Thymoma and thymic carcinoma in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Thymic tumors are epithelial tumors arising from the anterior mediastinum and constitute 0.2-1.5% of all adult malignancies but are exceptional in pediatric population. Thymic epithelial tumors (TETs) encompass a variety of histologic subtypes associated with different clinical outcomes. Due to its rarity in children, TETs' management requires a multidisciplinary approach. However, prognosis remains still poor, especially among patients with thymic carcinoma. This study presents the internationally recognized recommendations for the diagnosis and treatment of thymic tumors in children and adolescents, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) group within the EU-funded project Paediatric Rare Tumours Network - European Registry (PARTNER).

Facing the challenges of very rare tumors of pediatric age: The European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) background, goals, and achievements

It has become increasingly clear in recent years that we need to develop ad hoc strategies to combat very rare tumors (VRT) of pediatric age. In 2008, several schemes being run in different countries were pooled together to create the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) project: a cooperative study group that aimed to promote research in the relatively uncharted territory of rare tumors of pediatric age. EXPeRT members were able to activate different levels of cooperation to achieve their goals, and to obtain dedicated funding by participating in EU-financed projects. Their experiences emphasize the merits of networking, seeking new partnerships, joining forces, and pooling resources to extend the reach of research efforts, and ultimately improve the quality of patient care. Between 2018 and 2021, the EXPeRT has been active in establishing the Pediatric Rare Tumors Network - European Registry (PARTNER). This project had the main purposes of building a European common registry of pediatric VRT, but also the major task of developing diagnostic and treatment guidelines for VRT (or at least part of them). These clinical recommendations are the subject of a series of papers on Pediatric Blood and Cancer.

Value of the Sentinel Node Procedure in Pediatric Extremity Rhabdomyosarcoma: A Systematic Review and Retrospective Cohort Study

Background

Our aim is to show whether the sentinel node procedure (SNP) is recommendable for pediatric patients with extremity rhabdomyosarcoma (RMS). Lymph node metastases are an important prognostic factor in pediatric patients with extremity RMS. Accurate nodal staging is necessary to treat the patient accordingly. An alternative to the current recommended lymph node sampling is the sentinel node procedure (SNP).

Methods

A systematic review was performed summarizing all published cases of SNP in addition to 13 cases from our hospital and 8 cases from two other hospitals that have not been published before.

Results

For all patients (n = 55), at least one SLN was identified, but the SNP technique used was not uniform. The SNP changed the nodal classification of eight patients (17.0%) and had a false-negative rate of 10.5%.

Conclusions

The SNP is recommendable for pediatric patients with extremity RMS. It can change lymph node status and can be used to sample patients in a more targeted way than nodal sampling alone. Therefore, we recommend use of the SNP in addition to clinical and radiological nodal assessment for pediatric patients with extremity RMS.

ESGO-SIOPE guidelines for the management of adolescents and young adults with non-epithelial ovarian cancers

The European Society of Gynaecological Oncology and the European Society for Paediatric Oncology jointly developed clinically relevant and evidence-based guidelines for the management of adolescents and young adults aged 15 to 25 years with non-epithelial ovarian cancers, including malignant ovarian germ cell tumours, sex cord-stromal tumours, and small cell carcinoma of the ovary of hypercalcaemic type. The developmental process of these guidelines is based on a systematic literature review and critical appraisal process involving an international multidisciplinary developmental group consisting of experts from relevant disciplines (paediatric oncology, paediatric surgery, medical oncology, pathology, psycho-oncology, gynaecological oncology, and reproductive endocrinology). Given the specific and often complex issues involved in treating this group of patients, fertility sparing surgery and decrease of acute and long-term toxicities from treatment were important criteria for guidelines definition. Prior to publication, the guidelines were reviewed by 54 independent international practitioners in cancer care delivery.

Influence of Surgical Excision on the Survival of Patients With Stage 4 High-Risk Neuroblastoma: A Report From the HR-NBL1/SIOPEN Study

PURPOSE

To evaluate the impact of surgeon-assessed extent of primary tumor resection on local progression and survival in patients in the International Society of Pediatric Oncology Europe Neuroblastoma Group High-Risk Neuroblastoma 1 trial.

PATIENTS AND METHODS

Patients recruited between 2002 and 2015 with stage 4 disease > 1 year or stage 4/4S with MYCN amplification < 1 year who had completed induction without progression, achieved response criteria for high-dose therapy (HDT), and had no resection before induction were included. Data were collected on the extent of primary tumor excision, severe operative complications, and outcome.

RESULTS

A total of 1,531 patients were included (median observation time, 6.1 years). Surgeon-assessed extent of resection included complete macroscopic excision (CME) in 1,172 patients (77%) and incomplete macroscopic resection (IME) in 359 (23%). Surgical mortality was 7 (0.46%) of 1,531. Severe operative complications occurred in 142 patients (9.7%), and nephrectomy was performed in 124 (8.8%). Five-year event-free survival (EFS) ± SE (0.40 ± 0.01) and overall survival (OS; 0.45 ± 0.02) were significantly higher with CME compared with IME (5-year EFS, 0.33 ± 0.03; 5-year OS, 0.37 ± 0.03; P < .001 and P = .004). The cumulative incidence of local progression (CILP) was significantly lower after CME (0.17 ± 0.01) compared with IME (0.30 ± 0.02; P < .001). With immunotherapy, outcomes were still superior with CME versus IME (5-year EFS, 0.47 ± 0.02 v 0.39 ± 0.04; P = .038); CILP was 0.14 ± 0.01 after CME and 0.27 ± 0.03 after IME (P < .002). A hazard ratio of 1.3 for EFS associated with IME compared with CME was observed before and after the introduction of immunotherapy (P = .030 and P = .038).

CONCLUSION

In patients with stage 4 high-risk neuroblastoma who have responded to induction therapy, CME of the primary tumor is associated with improved survival and local control after HDT, local radiotherapy (21 Gy), and immunotherapy.

Outcome of patients with stage IV high-risk Wilms tumour treated according to the SIOP2001 protocol: A report of the SIOP Renal Tumour Study Group

INTRODUCTION

High-risk (HR) metastatic (stage IV) Wilms tumours (WTs) have a particular poor outcome.

METHODS

Here, we report the results of HR (diffuse anaplastic [DA] or blastemal type [BT]) stage IV WT treated patients according to the HR arm in the SIOP2001 prospective study.

RESULTS

From January 2002 to August 2014, 3559 patients with WT were included in the SIOP2001 trial. Among the 525 patients (15%) with metastatic WT, 74 (14%) had stage IV HR-WT. The median age at diagnosis was 5.5 years (range: 1.4-18.3). Thirty-four patients (47%) had BT-WT and 40 (53%) had DA-WT. Five-year event-free survival rates were 44 ± 17% and 28 ± 15% for BT-WT and DA-WT, respectively (p = 0.09). Five-year overall survival rates were 53 ± 17% and 29 ± 16% for BT-WT and DA-WT, respectively (p = 0.03). Metastatic complete response after preoperative treatment was significantly associated with outcome in univariate and multivariate analyses (hazards ratio = 0.3; p = 0.01). Postoperative radiotherapy of metastatic sites might also be beneficial. Forty-three of 74 patients experienced a relapse or progression predominantly in the lungs (80%). The median time to relapse/progression after diagnosis was 7.3 months (range: 1.6-33.3) and 4.9 months (range: 0.7-28.4) for BT-WT and DA-WT, respectively (p = 0.67). This is the first prospective evidence of inferior survival of stage IV BT-WT as compared with historical intermediate-risk WT. Survival of patients with stage IV DA-WT has not improved compared to the previous SIOP93-01 study.

CONCLUSION

These results call for new treatment approaches for patients with HR stage IV WT.

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.

Prognostic significance of age in 5631 patients with Wilms tumour prospectively registered in International Society of Paediatric Oncology (SIOP) 93-01 and 2001

BACKGROUND

To enhance risk stratification for Wilms tumour (WT) in a pre-operative chemotherapy setting, we explored the prognostic significance and optimal age cutoffs in patients treated according to International Society of Paediatric Oncology Renal Tumour Study Group (SIOP-RTSG) protocols.

METHODS

Patients(6 months-18 years) with unilateral WT were selected from prospective SIOP 93-01 and 2001 studies(1993-2016). Martingale residual analysis was used to explore optimal age cutoffs. Outcome according to age was analyzed by uni- and multivariable analysis, adjusted for sex, biopsy(yes/no), stage, histology and tumour volume at surgery.

RESULTS

5631 patients were included; median age was 3.4 years(IQR: 2-5.1). Estimated 5-year event-free survival (EFS) and overall survival (OS) were 85%(95%CI 83.5-85.5) and 93%(95%CI 92.0-93.4). Martingale residual plots detected no optimal age cutoffs. Multivariable analysis showed lower EFS with increasing age(linear trend P<0.001). Using previously described age categories, EFS was lower for patients aged 2-4(HR 1.34, P = 0.02), 4-10(HR 1.83, P<0.0001) and 10-18 years(HR 1.74, P = 0.01) as compared to patients aged 6 months-2 years. OS was lower for patients 4-10 years(HR 1.67, P = 0.01) and 10-18 years(HR 1.87, P = 0.04), but not for 2-4 years(HR 1.29, P = 0.23). Higher stage, histological risk group and tumour volume were independent adverse prognostic factors.

CONCLUSION

Although optimal age cutoffs could not be identified, we demonstrated the prognostic significance of age as well as previously described cutoffs for EFS (2 and 4 years) and OS (4 years) in children with WT treated with pre-operative chemotherapy. These findings encourage the consideration of age in the design of future SIOP-RTSG protocols.

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.

Defining and listing very rare cancers of paediatric age: consensus of the Joint Action on Rare Cancers in cooperation with the European Cooperative Study Group for Pediatric Rare Tumors

Although all tumours are rare in childhood, there are some particularly rare paediatric cancers which have not benefited from advances made by the international paediatric oncology network. To establish a shared definition and produce a list of these entities, the European Union Joint Action on Rare Cancers (JARC) promoted a consensus effort. The definition was based on the incidence rates estimated using the information network on rare cancers (RARECAREnet) database, pooling data from 94 population-based cancer registries and 27 countries. The RARECAREnet list of cancers was used to estimate the incidence rates. This list groups cancers by combining the International Classification of Diseases for Oncology, third edition, morphology and topography codes. According to the consensus, very rare paediatric cancers were identified as those with an annual incidence <2/1000000 and corresponded to 11% of all cancers in patients aged 0-14 years. Two subgroups were identified: tumour types typical of childhood (i.e. hepatoblastoma, pleuropulmonary blastoma, pancreatoblastoma) and those typical of adult age (i.e. carcinomas, melanoma). The threshold of 2/1000000 could also be adopted in populations aged 0-19 years: in this case, three tumour types had an incidence rate which was >2/1000000 (i.e. thyroid and testicular cancers and skin melanoma), but the consensus experts considered them as 'very rare' according to their clinical needs (e.g. shortage of knowledge and clinical expertise as the other rare paediatric cancers). The JARC consensus produced a definition and a list of very rare paediatric cancers which may represent a starting point for prioritising research on these tumours, based on data and patients' clinical needs.

Pediatric patients with cutaneous melanoma: A European study

INTRODUCTION

Cutaneous melanoma is rare in childhood and published studies have mainly been retrospective single-institution series or small case series. Given the absence of clinical protocols dedicated to pediatric melanoma, the treatment approach is generally extrapolated from the ones applied to adults.

METHODS

Coordinated by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT), this study collected patients prospectively registered between 2002 and 2012 under national cooperative projects dedicated to rare pediatric tumors in Italy, Poland, Germany, and France. Additional cases were collected from dermatology registries in Germany and Israel.

RESULTS

A total of 219 patients aged 0-18 years (median 14.4) were included in the analysis. Sentinel lymph node biopsy was performed in 112 patients (76% of those with Breslow thickness > 0.75 mm) and was positive in 37.5%. Systemic therapy was used in 33 cases. In stage III cases, survival rates were similar for patients who received (23 cases) or not (21 cases) adjuvant therapy. For the whole series, 3-year overall and disease-free survival rates were 91.4% and 84.0%, respectively (median follow-up 41.8 months). Tumor site, tumor stage, and ulceration influenced survival rates. Patients treated by pediatric oncologists (n = 140) were more likely to have advanced disease than those treated by dermatologists (n = 79).

DISCUSSION

This study would suggest that the clinical history of melanoma in children and adolescents might resemble that of adult counterpart. Cooperative efforts are needed to make new drugs more readily available to pediatric patients to increase the outcome of patient with advanced disease.

Position paper: Rationale for the treatment of children with CCSK in the UMBRELLA SIOP-RTSG 2016 protocol

The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) has developed a new protocol for the diagnosis, treatment, and follow-up monitoring of childhood renal tumours - the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). This protocol has been designed to continue international collaboration in the treatment of childhood renal tumours and will be implemented in over 50 different countries. Clear cell sarcoma of the kidney, which is a rare paediatric renal tumour that most commonly occurs in children between 2 and 4 years of age, is specifically addressed in the UMBRELLA protocol.

Position paper: Rationale for the treatment of Wilms tumour in the UMBRELLA SIOP-RTSG 2016 protocol

The Renal Tumour Study Group of the International Society of Paediatric Oncology (SIOP-RTSG) has developed a new protocol for the diagnosis and treatment of childhood renal tumours, the UMBRELLA SIOP-RTSG 2016 (the UMBRELLA protocol), to continue international collaboration in the treatment of childhood renal tumours. This protocol will support integrated biomarker and imaging research, focussing on assessing the independent prognostic value of genomic changes within the tumour and the volume of the blastemal component that survives preoperative chemotherapy. Treatment guidelines for Wilms tumours in the UMBRELLA protocol include recommendations for localized, metastatic, and bilateral disease, for all age groups, and for relapsed disease. These recommendations have been established by a multidisciplinary panel of leading experts on renal tumours within the SIOP-RTSG. The UMBRELLA protocol should promote international collaboration and research and serve as the SIOP-RTSG best available treatment standard.

Congenital mesoblastic nephroma 50 years after its recognition: A narrative review

Congenital mesoblastic nephroma (CMN) is a rare pediatric renal tumor with low malignant potential that most commonly occurs early in infancy. Treatment strategies are based on the few published CMN series, while a significant number of CMN patients have been described in case reports. The aim of this narrative review was to create an up-to-date overview of the literature. Complete surgical removal is curative in most cases. The risk of treatment-related mortality (both surgery- and chemotherapy-related) is relatively high in the first weeks of life, indicating that these young patients deserve special attention with respect to timing and type of treatment.

Outcome and prognostic factors in high-risk childhood adrenocortical carcinomas: A report from the European Cooperative Study Group on Pediatric Rare Tumors (EXPeRT)

OBJECTIVES

The aim of this retrospective international analysis was to evaluate the role of risk factors in pediatric patients with adrenocortical carcinoma (ACC) observed in European countries (2000-2013) in an attempt to identify factors associated with poor prognosis.

PROCEDURES

Data were retrieved from databases of Germany, France, Poland, and Italy, which form the European Cooperative Study Group on Pediatric Rare Tumors (EXPeRT). Patients were less than 18 years old, with at least one of the following tumor-related risk factors: metastases, volume more than 200 cm³ , Cushing syndrome, vascular or regional lymph node invasion, initial biopsy, or incomplete excision. Role of patients' age was also evaluated.

RESULTS

Eighty-two patients were evaluated: 62 with localized disease and 20 with metastases. The 3-year progression-free survival (PFS) and overall survival (OS) were 39% and 55% for the whole population, respectively, and 51% and 73% for localized diseases, respectively. Concerning the whole population, PFS and OS were influenced by distant metastases, tumor volume, lymph node involvement, age, and presence of two or more risk factors. Factors significant only at OS were vascular involvement and incomplete surgery. At multivariable analysis, the main factors at PFS were volume more than 200 cm³ (hazard ratio [HR]: 2.6, 95% confidence interval [CI]: 1.18-5.70) and presence of distant metastases (HR: 8.26, 95% CI: 3.49-19.51). The OS was significantly influenced by the presence of metastases (P < 0.0001). Concerning patients with localized tumors, the only significant prognostic factor was volume more than 200 cm³ with a HR of 4.38 (95% CI: 1.60-12.00) for PFS and of 3.68 (95% CI: 1.02-13.30) for OS.

CONCLUSIONS

Distant metastases and large tumor volume were the main unfavorable prognostic factors. Presence of two or more factors related to ACC was associated with an aggressive behavior of disease.

Improvements in the Treatment of Patients Suffering from Bladder-Prostate Rhabdomyosarcoma: A Report from the CWS-2002P Trial

PURPOSE

Modern treatment concepts for bladder/prostate rhabdomyosarcoma (BPRMS) are designed to improve survival, to reduce therapy intensity, and to increase bladder preservation rates. Nevertheless, treatment is not optimal. The purpose of this study was to analyze BPRMS patients treated within the CWS-2002P trial regarding outcome, treatment modalities, complications, and to compare the data with the precursor trial CWS-96.

METHODS

Fifty children with localized embryonal BPRMS were analyzed. Eight patients were excluded. Patients received neoadjuvant chemotherapy. At week 9, reassessment using MRI scan was performed. Depending on tumor size, age, and response, local therapy consisting of radiotherapy and/or surgery was initiated. After local therapy, systemic therapy was continued.

RESULTS

Patients' median age was 35.6 months. Median follow-up was 59 months. The 5-year OS was 84.5 % and the 5-year ES 79.9 %. Ten patients underwent combined radiochemotherapy and tumor resection (5-year ES: 87.5 %). Six patients were treated solely with radiochemotherapy (5-year ES: 60 %). Twenty-six patients received preoperative chemotherapy followed by tumor resection (ES: 80.8). One patient was treated with chemotherapy only and survived. The bladder preservation rate was 80.9 %.

CONCLUSIONS

The outcome within the CWS-2002P trial regarding OS and ES seemed to be better than in the precursor trial CWS-96 due to a reduction of protocol violations, but there was no statistical significant difference possibly due to low numbers. Radiotherapy was used less frequently, and the bladder preservation rate was slightly higher. Novel concepts will be required in the future to improve bladder preservation rates.

Omission of doxorubicin from the treatment of stage II-III, intermediate-risk Wilms' tumour (SIOP WT 2001): an open-label, non-inferiority, randomised controlled trial

BACKGROUND

Before this study started, the standard postoperative chemotherapy regimen for stage II-III Wilms' tumour pretreated with chemotherapy was to include doxorubicin. However, avoidance of doxorubicin-related cardiotoxicity effects is important to improve long-term outcomes for childhood cancers that have excellent prognosis. We aimed to assess whether doxorubicin can be omitted safely from chemotherapy for stage II-III, histological intermediate-risk Wilms' tumour when a newly defined high-risk blastemal subtype was excluded from randomisation.

METHODS

For this international, multicentre, open-label, non-inferiority, phase 3, randomised SIOP WT 2001 trial, we recruited children aged 6 months to 18 years at the time of diagnosis of a primary renal tumour from 251 hospitals in 26 countries who had received 4 weeks of preoperative chemotherapy with vincristine and actinomycin D. Children with stage II-III intermediate-risk Wilms' tumours assessed after delayed nephrectomy were randomly assigned (1:1) by a minimisation technique to receive vincristine 1·5 mg/m(2) at weeks 1-8, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26, and 27, plus actinomycin D 45 μg/kg every 3 weeks from week 2, either with five doses of doxorubicin 50 mg/m(2) given every 6 weeks from week 2 (standard treatment) or without doxorubicin (experimental treatment). The primary endpoint was non-inferiority of event-free survival at 2 years, analysed by intention to treat and a margin of 10%. Assessment of safety and adverse events included systematic monitoring of hepatic toxicity and cardiotoxicity. This trial is registered with EudraCT, number 2007-004591-39, and is closed to new participants.

FINDINGS

Between Nov 1, 2001, and Dec 16, 2009, we recruited 583 patients, 341 with stage II and 242 with stage III tumours, and randomly assigned 291 children to treatment including doxorubicin, and 292 children to treatment excluding doxorubicin. Median follow-up was 60·8 months (IQR 40·8-79·8). 2 year event-free survival was 92·6% (95% CI 89·6-95·7) for treatment including doxorubicin and 88·2% (84·5-92·1) for treatment excluding doxorubicin, a difference of 4·4% (95% CI 0·4-9·3) that did not exceed the predefined 10% margin. 5 year overall survival was 96·5% (94·3-98·8) for treatment including doxorubicin and 95·8% (93·3-98·4) for treatment excluding doxorubicin. Four children died from a treatment-related toxic effect; one (<1%) of 291 receiving treatment including doxorubicin died of sepsis, three (1%) of 292 receiving treatment excluding doxorubicin died of varicella, metabolic seizure, and sepsis during treatment for relapse. 17 patients (3%) had hepatic veno-occlusive disease. Cardiotoxic effects were reported in 15 (5%) of 291 children receiving treatment including doxorubicin. 12 children receiving treatment including doxorubicin, and ten children receiving treatment excluding doxorubicin, died, with the remaining deaths from tumour recurrence.

INTERPRETATION

Doxorubicin does not need to be included in treatment of stage II-III intermediate risk Wilms' tumour when the histological response to preoperative chemotherapy is incorporated into the risk stratification.

FUNDING

See Acknowledgments for funders.

Outcome of localised blastemal-type Wilms tumour patients treated according to intensified treatment in the SIOP WT 2001 protocol, a report of the SIOP Renal Tumour Study Group (SIOP-RTSG)

Blastemal-type Wilms tumour (BT-WT) has been identified as a high risk histological subgroup in WT assessed after pre-nephrectomy chemotherapy in trials of the International Society of Paediatric Oncology (SIOP) Renal Tumour Study Group. Therefore, in SIOPWT2001, post-operative chemotherapy for BT-WT was intensified aiming to improve survival. Survival analysis of all unilateral BT-WT patients (SIOPWT2001) (n=238), was compared with historical BT-WT controls (SIOP93-01) (n=113). 351/4061 (8.6%) unilateral non-metastatic BT-WT patients (SIOP93-01/SIOPWT2001) were studied. Median age at diagnosis was 43 months (Inter Quartile Range (IQR) 24-68 months), stages: I (n=140, 40%), II (n=106, 30%), III (n=105, 30%). BT-WTs were higher staged, showed greater volume decrease after pre-operative chemotherapy and were diagnosed at an older median age compared to other WT patients. Patient characteristics did not differ substantially between SIOP93-01 and SIOPWT2001. Univariate analysis showed a 5-year event-free survival (EFS) of 80% (95% confidence interval (CI): 75-86%) (SIOPWT2001) compared to 67% in SIOP93-01 (95% CI: 59-76%; p=0.006) and overall survival (OS) of 88% (95% CI: 83-93%) (SIOPWT2001) compared to 84% (95% CI: 77-91%; p=0.4) in SIOP93-01. 95% of relapses were distant metastases (SIOP93-01/SIOPWT2001). Treatment protocol, age at diagnosis, tumour stage (III versus I/II) and volume (at surgery), were prognostic variables for EFS (uni- and multivariate Cox regression analysis). Independent prognosticators for OS were age at diagnosis, tumour stage and volume (at surgery). The most significant survival benefit of intensified treatment, was observed in Stage I (EFS 96% in SIOPWT2001 (OS 100%), 71% in SIOP93-01 (OS 90%)). BT-WT derived benefits from more intensive chemotherapy as reflected by a reduction in relapse risk. However, the benefit of the more intensive chemotherapy to improve OS was only observed in stage I BT-WTs, by adding doxorubicin.

The current status of treatment of Wilms' tumor as per the SIOP trials

This paper attempts to briefly describe the International Society of Paediatric Oncology (SIOP) policy of treatment of nephroblastoma since first study (SIOP 1) launched in 1971 until today. It focuses on the advantages of the preoperative chemotherapy and the stratification of patients induced this way. Marked efficacy of the pretreatment opened the way for less aggressive surgical management also in case of the "so-called" regular unilateral cases: Nephron-sparing surgery and minimal invasive techniques will probably find its place in this field of pediatric surgical oncology; however, very careful selection of cases must be the priority.

Current concepts in surgery for Wilms tumor--the risk and function-adapted strategy

This article describes the current status of surgical approach to Wilms tumor. Combined multimodal treatment including classical open nephrectomy is still the most recommended and offers excellent survivals. Patients suffering from Wilms tumor as potentially very long-term survivors also need great care of quality of their further life. Nephron-sparing surgery seems an important step in this regard; however, selection of patients is necessary to avoid failures and decreasing survival rate. A new method of describing this kind of procedure developed within the SIOP Renal Tumours Study Group (RTSG) offers an opportunity for further comparisons and assessment. Minimally invasive nephrectomy is not recommended in the treatment of Wilms tumor; however, in experienced hands and correctly selected (rare) cases, minimally invasive nephrectomy may offer the same outcome as the classical open approach. Lymph nodes sampling, essential for reliable staging, appeared rarely correct in children operated by this technique. Any competition with partial nephrectomy should be avoided in favor of the nephron-sparing approach. A small proportion of patients still create surgical difficulties and this is in fact the target group for further surgical reviews. Their prognosis seems at least in part surgeon-dependent. Few clinical factors available preoperatively (tumor side, age, and tumor volume) were detected as influencing potential risk of surgical failures. Once identified, this needs increased attention from the surgical point of view.

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.

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.

Challenges in the local treatment of large abdominal embryonal rhabdomyosarcoma

BACKGROUND

Embryonal rhabdomyosarcoma is the most common pediatric soft tissue sarcoma. The best local treatment in large, nonmetastatic primary unresected nongenitourinary embryonal rhabdomyosarcoma of the abdomen (LARME) is however unclear.

METHODS

We analyzed patients with LARME treated in four consecutive CWS trials. All diagnoses were confirmed by reference reviews. Treatment included multiagent chemotherapy and local treatment of the primary tumor with surgery and/or radiotherapy. The impact of primary debulking surgery (PDS) also was studied.

RESULTS

One hundred patients <21 years with a median age of 4 years had LARME. Sixty-one of them had a tumor >10 cm in diameter at diagnosis. PDS was performed in 19 of 100 children. The outcomes of patients with PDS were similar to those of the other patients. In 36 children, the tumor was resected after induction chemotherapy; 60 RME were irradiated. The toxic effects of radiochemotherapy were not significantly increased compared with the nonirradiated patients. With a median follow-up of 10 years, the 5-year EFS and OS were 52 ± 10 and 65 ± 9 %, respectively. Significant risk factors in multivariate analysis were age >10 years; no achievement of complete remission; and inadequate secondary local treatment, defined as incomplete secondary resection or no radiation.

CONCLUSIONS

Children with LARME have a fair prognosis, despite an often huge tumor size and unfavorable primary site, if the tumors can either be resected or irradiated following induction chemotherapy. PDS was only performed in a small subgroup. Radiation performed concomitantly with chemotherapy did not increase the acute toxicity significantly.

Treatment and outcome of patients with relapsed clear cell sarcoma of the kidney: a combined SIOP and AIEOP study

Background:

Clear cell sarcoma of the kidney (CCSK) is an uncommon paediatric renal tumour. Relapses occur in about 15% of the patients. Since detailed clinical information on relapsed CCSK is scarce, the current study aims to describe outcome of patients with relapsed CCSK treated according to recent European protocols.

Patients and methods:

We analysed prospectively collected data of all CCSK patients who developed a relapse after complete remission at the end of primary treatment, entered onto SIOP and AIEOP trials between 1992 and 2012.

Results:

Thirty-seven of 237 CCSK patients (16%) treated according to SIOP and AIEOP protocols developed a relapse. Median time from initial diagnosis to relapse was 17 months (range, 5.5 months - 6.6 years). Thirt-five out of thirty-seven relapses (95%) were metastatic; the most common sites of relapse were the brain (n=13), lungs (n=7) and bone (n=5). Relapse treatment consisted of chemotherapy (n=30), surgery (n=19) and/or radiotherapy (n=18), followed by high-dose chemotherapy and autologous bone marrow transplantation (ABMT) in 14 patients. Twenty-two out of thirty-seven patients (59%) achieved a second complete remission (CR); 15 of whom (68%) developed a second relapse. Five-year event-free survival (EFS) after relapse was 18% (95% CI: 4%–32%), and 5-year overall survival (OS) was 26% (95% CI: 10%–42%).

Conclusions:

In this largest series of relapsed CCSK patients ever described, overall outcome is poor. Most relapses are metastatic and brain relapses are more common than previously recognised. Intensive treatment aiming for local control, followed by high dose chemotherapy and ABMT, seems to be of benefit to enhance survival. Novel development of targeted therapy is urgently required.

Nephroblastoma: does the decrease in tumor volume under preoperative chemotherapy predict the lymph nodes status at surgery?

BACKGROUND

Partial nephrectomy (NSS) for unilateral nephroblastoma may be beneficial, although in case of regional lymph node (LN) involvement, radiotherapy counteracts the functional benefit of NSS. The aim is to verify whether decrease of tumor volume under preoperative chemotherapy implies clearance of regional LN.

PROCEDURE

SIOP 9301 (1993-2001) collected 1,450 localized nephroblastoma patients of whom 1,360 (93%) had sufficiently available data and were retrospectively reviewed.

RESULTS

Histologic subtypes were classically distributed. Patients were divided in those with tumor positive LN (76, 5.5%) and those with tumor negative LN (1,284, 94.5%) at surgery. In the LN(+) group, the tumor volume changed from a median of 554 (318-772) to 192 (63-458) ml = 67% (27-88%) during preoperative ChT. In the LN(-) group-377 (200-612) to 130 (44-294) ml = 62% (28-83%) (NS). Increase of tumor volume was observed in 16% of patients with LN(+), and 11% of those with LN(-) (NS); ranges are interquartile. Initial tumor volume was significantly larger in the LN(+) patients (P = 0.00091) but not different (NS) at surgery; patients with initial tumor volume under 318 ml had the regional LN involved significantly less frequently (P = 0.00751).

CONCLUSIONS

Change in tumor volume under preoperative chemotherapy is not a predictor for LN status at surgery, although larger initial volume is associated with a higher risk of LN invasion. The decrease of tumor volume is not a good criterion for the safety of NSS. The low rate of LN(+) (5.5%) indicates that this risk is low.

Pancreatoblastoma: a report from the European cooperative study group for paediatric rare tumours (EXPeRT)

BACKGROUND

Pancreatoblastoma is a very rare malignant tumour typically occurring in the early years of life. Due to its rarity, standardised diagnostic and therapeutic guidelines are not available for pancreatoblastoma.

METHODS

The newborn cooperative group denominated EXPeRT - European cooperative study group for paediatric rare tumours - combined in a joint analysis of all cases registered between 2000 and 2009 by the national groups of Italy, France, United Kingdom, Poland and Germany.

RESULTS

Twenty patients <18years old (median age 4years) were analysed: nine had distant metastases at diagnosis. Seventeen patients had tumour resection, at initial or delayed surgery. Eighteen received chemotherapy (response rate 73%), seven received radiotherapy. For the whole series, 5-year event-free survival and overall survival were 58.8% and 79.4%, respectively. Outcome did not correlate with tumour site and size, but was strongly influenced by the feasibility of tumour complete resection.

CONCLUSIONS

This international study confirms the rarity of the disease, the critical role of surgical resection both as therapy and as a prognostic variable, and the potential efficacy of chemotherapy. The adoption of an intensive multidisciplinary approach is required, as well as the referral to highly experienced centres. Further international cooperation is needed to collect larger series and stimulate biological studies to improve our understanding of the biology and the natural history of PBL.

Treatment efficiency, outcome and surgical treatment problems in patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma: a report from the Cooperative Soft Tissue Sarcoma trial CWS-96

BACKGROUND

To analyze the clinical course, treatment modalities, complications and outcome of patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma (BPRMS) treated on the CWS-96 trial.

PROCEDURE

There were 85 patients with BPRMS enrolled and 63 patients with embryonal non-metastatic BPRMS were analyzed. Fifty-six patients received neoadjuvant chemotherapy and response was assessed radiographically after 9 weeks. Local therapy with radiation and or surgery was performed based on age, tumor size, and response. Patients were treated with adjuvant chemotherapy following local control.

RESULTS

Patient's age ranged from 0 to 16 years with a median follow up of 5.3 years. Eighty nine percent of the patients had IRS group III disease. The 5-year overall survival (OS) for the whole group was 76.3 ± 5.6% and the 5-year event-free survival (EFS) 69.8 ± 6.2%. Seventeen patients underwent preoperative radiochemotherapy followed by tumor resection (5-year-OS: 87.8 ± 8.1%). Eight patients were treated with solely radiochemotherapy (87.5 ± 11.7%). Twenty-five patients received chemotherapy and tumor resection (OS: 83.6 ± 7.5%). Thirteen patients underwent incomplete tumor resection and were treated with radiochemotherapy postoperatively (OS: 39.9 ± 14.8%, P < 0.05 vs. other groups).

CONCLUSIONS

Local therapy is an important factor for prognosis of localized embryonal BPRMS. Inadequate primary or secondary surgery compromises the outcome and should be avoided. Radiotherapy alone, complete surgical tumor resection or combined preoperative radiotherapy with surgical resection lead to similar good local control rates and prognosis.

Differential expression of invasion promoting genes in childhood rhabdomyosarcoma

Expression profiling of tumor tissue allows a systematic search for targeted therapies and offers relevant prognostic information. Molecular studies on rhabdomyosarcoma (RMS) revealed a more differentiated classification than the histological subgrouping into embryonal (RME) and alveolar (RMA) rhabdomyosarcoma, and reflected the chromosomal aberrations found in RMS. We addressed biological processes like cell migration and emerging drug resistance by expression profiling to identify mechanisms of metastasic invasion and differential response to chemotherapy in RMS. Gene expression analysis was performed in 19 RMS samples using the Affymetrix U133 Plus2 array. Validation of target genes was performed by qRT-PCR. Data were analyzed using Pathway analysis software. Involvement of these genes in invasion processes was evaluated in knock-down experiments using specific interference RNA and Matrigel(TM) invasion assay. In RMA tissues 211 of 534 genes were overexpressed, in RME tissues 323 genes were overexpressed. Pathway analysis software identified a group of genes involved in cell growth, morphology and motility. In patients with distant metastases especially transcription factors such as FOXF1 and LMO4 showed a high expression, which were described as determinants of tumor cell migration. Down-regulation of these factors inhibited the invasion of RMS cells >10-fold. Microarray technology is a powerful method not only to classify RMS samples, but also to identify major regulatory processes. Functional evaluation of LMO4 and FOXF1 identified targets of a molecular network for preventing metastatic invasion in RMS.

Thymic carcinoma in children: a report from the Polish Pediatric Rare Tumors Study

BACKGROUND

Invasive thymomas and thymic carcinomas are rare tumors jointly accounting between 0.2% and 1.5% of malignancies in adults. They are usually at an advanced stage when diagnosed and have both high recurrence and poor survival rates. In this report, the aim is to explore our experience in the treatment of thymic carcinomas in Polish children.

PROCEDURE

The clinical data of nine children with thymic carcinomas, treated between 1992 and 2008 in the Polish oncological and surgical centers was retrospectively analyzed.

RESULTS

In five cases, presenting symptoms resulted from the compression of the respiratory ways by the mediastinal tumor. In two children paraneoplastic autoimmune syndromes were associated with thymic carcinoma. In accordance with the Masaoka classification, two patients had stage II, five had stage III, and two had stage IV of the disease. Diagnostic biopsy of mediastinal tumor was performed on eight patients and one underwent complete primary resection and subsequently received radiotherapy; he has passed 11 years since the conclusion of therapy. Six patients received multi-drug chemotherapy with or without steroids. Delayed surgery was performed in four children (R0-2, R1-1, and R2-1). After complete resection, one child received chemotherapy. In three patients, chemotherapy and radiotherapy was administered. Seven patients died, including six due to progression of the disease with the other as a result of complications following chemotherapy; only two patients classed at stage II remain alive.

CONCLUSIONS

Most thymic tumors in pediatric patients are inoperable at diagnosis, which results in poor prognosis. Improved chemotherapy approaches are needed.