Risk-based management: current concepts of treating malignant solid tumors of childhood

Primary rhabdomyosarcoma of tunica vaginalis misdiagnosing as hydrocele: A case report and literature review

Primary rhabdomyosarcoma of tunica vaginalis is very rare. We report a case of a 15-year-old man presenting as hydrocele. Pre-operatively, no masses were detected by ultrasonography. Hydrocelectomy was performed. At surgery, a 0.8 cm polypoid nodule and diffusely thickened tunica were found. Pathologic examination finally revealed rhabdomyosarcoma. A PET-CT was then performed and indicated scrotal implantation metastasis. The patient underwent radical inguinal orchiectomy and was treated with chemotherapy and radiotherapy after surgery. At 12 months of follow-up, he remained disease-free.

Evaluation of Rhodiola crenulata on growth and metabolism of NB-1691, an MYCN-amplified neuroblastoma cell line

Outcomes of children with high grade neuroblastoma remain poor despite multi-agent chemotherapy regimens. Rhodiola crenulata extracts display anti-neoplastic properties against several cancers including breast cancer, melanoma, and glioblastoma. In this study, we evaluated the anti-neoplastic potential of Rhodiola crenulata extracts on human neuroblastoma cells. Through this work, cell viability and proliferation were evaluated following treatments with ethanol (vehicle control) or Rhodiola crenulata extract in neuroblastoma, NB-1691 or SK-N-AS cells, in vitro. HIF-1 transcriptional activity was evaluated using a dual luciferase assay. Quantitative real-time polymerase chain reaction was utilized to assess the expression of HIF-1 targets. Selected metabolic intermediates were evaluated for their ability to rescue cells from Rhodiola crenulata extract-induced death. Lactate dehydrogenase, pyruvate kinase, and pyruvate dehydrogenase activities and NAD₊/NADH levels were assayed in vehicle and Rhodiola crenulata extract-treated cells. The effects of Rhodiola crenulata extracts on metabolism were assessed by respirometry and metabolic phenotyping/fingerprinting. Our results revealed striking cytotoxic effects upon Rhodiola crenulata extract treatment, especially prominent in NB-1691 cells. As a greater response was observed in NB-1691 cells therefore it was used for remaining experiments. Upon Rhodiola crenulata extract treatment, HIF-1 transcriptional activity was increased. This increase in activity correlated with changes in HIF-1 targets involved in cellular metabolism. Serendipitously, we observed that addition of pyruvate protected against the cytotoxic effects of Rhodiola crenulata extracts. Therefore, we focused on the metabolic effects of Rhodiola crenulata extracts on NB-1691 cells. We observed that while the activities of pyruvate kinase and pyruvate dehydrogenase activities were increased, the activity of lactate dehydrogenase activity was decreased upon Rhodiola crenulata extract treatment. We also noted a decline in the total NAD pool following Rhodiola crenulata extract treatment. This correlated with decreased cellular respiration and suppressed utilization of carbon substrates. Through this work, we observed significant cytotoxic effects of Rhodiola crenulata extract treatment upon treatment on NB-1691 cells, a human neuroblastoma cell line with MYCN amplification. Our studies suggest that these cytotoxic effects could be secondary to metabolic effect induced by treatment with Rhodiola crenulata extract.

Wilms' Tumor Protein 1 and Enzymatic Oxidation of 5-Methylcytosine in Brain Tumors: Potential Perspectives

The patterns of 5-methylcytosine (5mC) and its oxidized derivatives, 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine (5caC) are reportedly altered in a range of cancers. Likewise, Wilms' Tumor protein 1 (WT1), a transcription factor essential for urogenital, epicardium, and kidney development exhibits aberrant expression in multiple tumors. Interestingly, WT1 directly interacts with TET proteins that catalyze the enzymatic oxidation of 5mC and exhibits high affinity for 5caC-containing DNA substrates in vitro. Here we review recent developments in the fields of Tet-dependent 5mC oxidation and WT1 biology and explore potential perspectives for studying the interplay between TETs and WT1 in brain tumors.

Loss of heterozygosity on chromosome 16q increases relapse risk in Wilms' tumor: a meta-analysis

Wilms’ tumor (WT) is the most frequent malignant renal tumor in children. The survival rate is lower in patients with recurrence, and the factors that influence relapse in WT are not fully understood. Loss of heterozygosity on chromosome 16q (LOH 16q) has been reported to be associated with the relapse in WT, but this remains controversial. We performed a meta-analysis to clarify this. PUBMED, EMBASE, and the Cochrane Library were searched up to March 17, 2017. Ten studies involving 3385 patients were ultimately included in the meta-analysis. The meta-analysis showed that LOH 16q was significantly associated with the relapse in WT (relative risk [RR] = 1.74, 95% confidence interval [CI] = 1.43–2.13, P < 0.00001; hazard ratio [HR] = 1.76, 95% CI = 1.38–2.24, P < 0.00001). No significant heterogeneity among studies or publication bias was found. Sensitivity analysis showed omitting one study in each turn could not change the results. Subgroup analysis based on two studies indicated LOH 16q was more effective on elevated replase risk in patients with favorable-histology WT (RR = 2.52, 95% CI = 1.68–3.78, P < 0.00001; HR = 2.99, 95% CI = 1.84–4.88, P < 0.0001) but further work are needed to confirm this. These findings confirm that LOH 16q increased the relapse risk in WT, but more studies are required to further assess the association between LOH 16q and WT relapse among different subgroups.

Clinical manifestations of neuroblastoma with head and neck involvement in children

OBJECTIVE

The purpose of our study is to review our 15-year experience with pediatric patients who have been diagnosed with neuroblastoma, and to determine their most frequent head and neck manifestations and symptoms.

STUDY DESIGN

Retrospective chart review of electronic medical record.

SETTING

An academic, tertiary care pediatric hospital.

SUBJECTS AND METHODS

IRB approval from the Office of Research Integrity at Children's Mercy Hospital was obtained. The hospital tumor database was analyzed to identify patients with neuroblastoma, ganglioneuroblastoma, and esthesioneuroblastoma diagnosed between 1997 and 2012. We recorded the various clinical signs and symptoms these patients displayed at their initial presentation, focusing on patients with head and neck involvement. We then determined the relative incidence of these various findings.

RESULTS

Our review yielded 118 patients diagnosed with neuroblastoma, ganglioneuroblastoma, or esthesioneuroblastoma over our 15 year study period. 7 of the 118 patients were diagnosed with primary tumors of the head and neck. Another 19 patients had metastatic head and neck involvement. For those with primary disease, presence of a neck mass and signs of Horner's syndrome were the most common findings. For metastatic disease, craniofacial bony metastasis was the most frequent finding in our study.

CONCLUSIONS

Based on our data, there are a handful of findings that occur frequently in pediatric head and neck neuroblastoma. Any persistent neck mass, unexplained Horner's syndrome, or periorbital ecchymosis should be carefully evaluated. This study should serve as an aid for the otolaryngologist to be aware of the possible manifestations of this malignancy in children.

Pattern of malignant solid tumors and lymphomas in children in the east delta of Egypt: A five-year study

Worldwide, the incidence and mortality rates of childhood cancers differ. The study of incidence patterns and survival rates in childhood malignancies is important in aiding in the planning of treatment centers and in obtaining further information with regard to the etiology. Few studies have investigated the survival in cases of childhood solid tumors in Egypt. The aim of the current study was to evaluate the patterns, frequency and outcome of solid tumors and lymphomas in children admitted to and followed up at the Pediatric Oncology Department of Zagazig University Hospital (Zagazig, Egypt) over a duration of 5 years (January 2004 to December 2008). A retrospective study was conducted, which included 155 children with solid tumors and lymphomas. The medical records were reviewed and the relevant data collected, in particular, those concerning demographic, clinical, histopathological, laboratory and imaging data as well as the treatment plans and outcomes. The mean age of patients was 5.6±3.04 years at diagnosis. The patients comprised 94 males and 61 females. Non-Hodgkin lymphoma (NHL) was the most common tumor type, followed by neuroblastoma (31.0 and 29.0%, respectively). When patients were stratified in terms of age (<5, ≥5 but <10, and ≥10 years), the <5-years-of-age group exhibited the greatest number of patients. Fever, pallor and pain were the most frequent initial clinical presentations among the patients and stage II was the most common stage (39.1%) followed by stage IV, III and I (35.0, 20.3 and 5.6% respectively). The overall 5-year survival rate in the study group was 66.7%. The survival rate was significantly higher in patients with Wilm’s tumor and Hodgkin lymphoma, followed by NHL (92.0, 88.0 and 72.0%, respectively; P<0.001), while the mortality rate was significantly higher in patients with neuroblastoma (P<0.001). In conclusion, NHL and neuroblastoma were the most common tumors; the survival rates were higher in patients with Wilm’s tumor and Hodgkin lymphoma and lower in patients with neuroblastoma. A larger multicenter study is required to further investigate the conclusions drawn from this study.

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

OBJECTIVE

To determine event free survival (EFS) of children with Wilms tumor (WT) and metastatic liver disease at diagnosis.

SUMMARY AND BACKGROUND DATA

We reviewed patients with stage IV Wilms tumor treated on National Wilms Tumor Study 4 and 5 to ascertain if they have a worse prognosis than other Stage IV disease.

METHODS

A total of 742 patients (pts) with stage IV disease were assessed for EFS (95% confidence interval [CI]) at 5 years after diagnosis. Cohorts included those who underwent resection of the liver lesions compared with those who received only chemotherapy and radiotherapy.

RESULTS

A total of 742 patients with stage IV Wilms tumor were enrolled on NWTS-4 and 5, 111 of who had liver metastases. Of these, 96 had favorable histology disease and are the focus of this analysis. Twenty-two patients had a primary liver resection (wedge resection, 18 and lobectomy, 4). After chemotherapy and/or radiation, 13 patients underwent liver resection (wedge resection, 7; lobectomy, 5; and trisegmentectomy, 1). Seventy-one patients (67%) did not undergo surgery for their liver disease. In 14 patients, the liver disease disappeared with chemotherapy only. Eighty-two patients received abdominal radiation. EFS for the patients with metastatic FH Wilms tumor was 75% (95% confidence interval [CI]: (71%, 78%), EFS by Stage IV category was: lung only 76% (95% CI: 72%, 80%) (513 patients); liver, not lung 76% (95% CI: 58%, 87%) (34 patients), liver and lung 70% (95% CI: 57%, 80%) (62 patients), and other sites 64% (95% CI: 42%, 79%) (25 patients). There were no significant differences among stage IV groups (P = 0.60). EFS (95% CI) for the patients with primary resection of the liver metastases (22 patients) was 86% (63%, 95%) compared with 68% (56%, 78%) (P = 0.09) for the 74 with no primary resection of liver metastases. There was no significant difference in EFS for patients with FH Wilms tumor treated with chemotherapy compared with that of patients treated with chemotherapy and radiation (P = 0.63). The EFS (95% CI) for each of the subsets was; no abdominal radiation: 64% (34%, 83%); abdominal radiation, no boost: 77% (55%, 89%); abdominal radiation, boost: 72% (58%, 82%) (P = 0.05).

CONCLUSION

Liver metastasis at diagnosis is not an adverse prognostic factor for stage IV metastatic FH WT.

Paratesticular rhabdomyosarcoma presenting as thickening of the tunica vaginalis

Pediatric paratesticular primary malignant tumors are rare, and most of them correspond to rhabdomyosarcomas (RMS). Paratesticular RMS has a better prognosis than RMS originating in other locations, because of its favorable histology and possible early diagnosis. The diagnosis relies upon the US findings of a paratesticular hypervascular mass in an adequate clinical setting. We report the unusual appearance of an infiltrating RMS tumor in a 3-year-old boy. The tumor presented as thickening of the tunica vaginalis. Atypical US appearance and discordance with clinical features caused suspicion of a tumoral process, allowing early diagnosis and treatment.

A rare case of primary omental neuroblastoma and resection of the recurrent tumor by laparoscopy

Neuroblastoma is the most common extracranial solid tumor in children. Primary omental neuroblastoma has never been reported in the English literature. A 4-year-old girl presented with a mobile abdominal mass; primary omental neuroblastoma was diagnosed. There was tumor recurrence after complete tumor resection. She received chemotherapy and underwent laparoscopic resection of the recurrent tumor. There was no tumor recurrence after 1 year of follow-up.

Role of prognostic factors in the management of pediatric solid tumors

The importance of prognostic factors in predicting outcome in pediatric oncology is largely recognized, and most current protocols tailor treatment based on risk stratification. Further refinements of classical staging systems are ongoing, and the future of pediatric oncology is in the development of strategies based on individual tumor characteristics. This review details significant advances in our understanding of prognostic factors in the most common pediatric solid tumors and potential applications for clinical management.

Imaging in unilateral Wilms tumour

Wilms tumour is one of the most common malignancies in children, with an excellent prognosis after therapy. There is a very diverse approach to treatment according to geographical location. This variation in therapeutic attitude toward Wilms tumour, particularly between the United States and Europe, has consequences for the choice of imaging modality at diagnosis. In Europe, the International Society of Paediatric Oncology (SIOP) treatment protocol is based on chemotherapy followed by surgery. Imaging (US, CT and MRI), clinical history and examination will help predict whether the findings are consistent with Wilms tumour. Furthermore, in the UK preoperative image-guided biopsy is advised to help identify the small group of patients who, despite typical imaging features of Wilms tumour, have other types of neoplasia that require alternative management. In the United States, the National Wilms Tumor Study (NWTS) advises surgery prior to chemo- and radiotherapy. Hence imaging must provide detailed anatomical information for surgical planning. This article discusses the role of imaging at diagnosis and the relative strengths and weaknesses of the available radiological techniques. We also focus on imaging the lung for metastatic disease and the consequences (to the patient's ultimate outcome) of CT-diagnosed small pulmonary nodules and discuss the radiological diagnosis and consequences of tumour rupture present at diagnosis.

Surgical implications for liver metastases in nephroblastoma--data from the SIOP/GPOH study

BACKGROUND

In children with Wilms' tumor, the 5-year overall survival rate is over 90% in the SIOP/GPOH study group. However, a small group of patients have tumor lesions in the liver at the time of initial diagnosis or as a recurrence. This group seems to have a worse prognosis in terms of survival. The treatment and outcome of patients with a hepatic recurrence were analyzed compared to previously published data of patients with primary hepatic metastases.

PATIENTS AND METHODS

We reviewed the records of 45 out of 1365 patients enrolled in the SIOP 93-01/GPOH study and the SIOP 2001/GPOH study between April 1, 1994 and September 30, 2004. Median age at diagnosis was 6.49 years (1.37-34.16 years) in 29 patients who were initially presented with hepatic metastases (group I) with 9 males and 20 females. In 16 children who had a recurrence of a nephroblastoma in the liver (group II), median age at diagnosis was 4.62 years (1.84-31.08 years) with 9 males and 7 females.

RESULTS

In group I out of 29 patients, 11 died at a median of 13.07 months. Overall survival in group I was 62.58%. In group II, 9 patients died at a median 52 months. Overall survival in group II was 54.7%.

CONCLUSION

This report suggests that when complicated by metastases of the liver, Wilms' tumor has a less favorable outcome. Chemotherapy and radiotherapy play a definitive role in the treatment of these children. The importance of complete resection of hepatic lesions in both groups should be emphasized.

Wilms tumor: progress and considerations for the surgeon

Wilms tumor (WT) or nephroblastoma is the most common tumor of renal origin found in children. It accounts for 6% of all pediatric tumors and is the second most frequent intrabdominal solid organ tumor found in children. Initial survival rates in the early part of the last century was only 30%, but now long-term survival in both North America and European trials is approaching 85% with many low-stage tumors significantly higher. Treatment is now progressing towards "risk-based management"- based not only on stage and histology but also incorporating genetic markers [Dome JS, Grundy PE, Perlman EJ, Ehrlich PF, et al. Protocols for the renal tumors study. Childrens Oncology Group. [www.childrensoncologygroup.org. 2007.]. Within the multidisciplinary treatment team the surgeon plays a critical role in the diagnosis, staging and the surgeon's technical skills and judgment directs therapy and impacts outcome. The next generation of treatment for children with WT will focus on identifying subsets of patients who can be defined by some criterion as having a different outcome than their similar stage peers and who therefore require a variation in management. These include children with WT that have unsatisfactory long-term survival (less then 75%), patients of good survival but high potential for late effects and a final challenge are those children with both a poor survival and a high potential for late effects. This article presents a review of the most recent treatment considerations for WT with a focus on the surgeon's role to ensure a good outcome.

Criteria for Optimizing Prognostic Risk Groups in Pediatric Cancer: Analysis of Data From the Children's Oncology Group

Purpose

Physicians who treat cancer often attempt to identify patient subgroups that are homogeneous in their chance of recurrence or death as a way to target the more toxic and presumably more effective treatments to patients with the worst prognosis. However, to date, prognosis-based treatment assignment in pediatric cancer has not been based on a quantitative assessment of the risks and benefits of different treatment strategies or on morbidity and efficacy outcome measures that are relevant to children.

Methods

We performed a quantitative analysis of the risks and benefits of prognosis-based treatment assignment in two examples from the Children's Oncology Group using a mathematical model of cancer cure and permanent treatment morbidity and defined an optimality criterion for assigning treatments to specific risk groups.

Results

In stage 4 MYCN-unamplified neuroblastoma, age-based risk grouping distinguishes clearly between patients with high and low risk of recurrence. However, our analysis suggests that the optimal age cut point depends profoundly on the morbidity of the treatments being considered and agrees with current published recommendations only for treatments that add significant morbidity. In Hodgkin's lymphoma, under our model, no clearly optimal risk groupings exist, and a compelling quantitative rationale for defining risks group at all may not exist.

Conclusion

Our analysis illustrates the inadequacy of naïve application of statistical criteria for defining prognostic risk groups in pediatric cancer and highlights the importance of quantifying treatment morbidity when defining risk groups or when deciding whether risk grouping is warranted.

Induction of cytolytic T lymphocytes against pediatric solid tumors in vitro using autologous dendritic cells pulsed with necrotic primary tumor

PURPOSE

Effective and generally applicable methods for generating cancer vaccines in children have not been defined. Dendritic cells (DCs) are the most potent professional antigen-presenting cells capable of activating primary cytolytic T cells. We tested the ability of DCs generated from pediatric patients' peripheral blood monocytes and pulsed with a necrotic tumor to activate autologous tumor-specific cytolytic T cells.

METHODS

Tumor and peripheral blood cells were obtained from pediatric patients undergoing biopsy or resection for advanced solid tumors according to an institutional research board-approved protocol and after acquiring informed consent from them. To generate DCs, we treated peripheral blood monocytes with granulocyte-macrophage colony stimulating factor and interleukin (IL)-4. Maturation was induced with a cytokine cocktail (CC) containing tumor necrosis factor-alpha, IL-6, IL-1beta, and prostaglandin E2. The DC phenotype was assayed using flow cytometry. Tumor necrosis was induced by exposure to UV-B irradiation (1000 mJ). Dendritic cells pulsed with a UV-B-treated primary tumor and matured with CC were used to stimulate autologous peripheral blood lymphocytes weekly. Tumor-specific cytolytic activity was assayed using 4-hour 51Cr release.

RESULTS

Peripheral blood monocytes isolated from pediatric patients differentiated into immature DCs (CD14-, MHCII+ [major histocompatibility complex], CD80(low), CD86(low)) in the presence of granulocyte-macrophage colony stimulating factor and IL-4. Cytokine cocktail induced maturation of DCs, as characterized by increased expressions of MHCII, CD83, CD80, and CD86. Patients' peripheral blood lymphocytes stimulated in vitro with DCs loaded with a necrotic primary tumor and matured with CC specifically lysed autologous neuroblastoma in 7 of 9 patients.

CONCLUSION

Dendritic cells generated from the peripheral blood of children with advanced solid tumors and pulsed with a necrotic primary tumor undergo maturation and effectively stimulate autologous tumor-specific cytolytic T cells in vitro. We describe a simple method for generating a vaccine capable of activating cytotoxic T cells against pediatric solid tumors that does not require the genetic identification of tumor-associated antigens.

Prognostic significance of biochemical heterogeneity of catecholaminergic clones in neuroblastoma

BACKGROUND/PURPOSE

Genetic heterogeneity of neuroblastic tumors leads to biochemical changes that manifest themselves in different symptoms and clinical courses, which may vary from spontaneous regression and remission to progression with fatal outcome.

METHODS

To test the hypothesis that ratios of dopamine (DA) to noradrenaline and of DA to vanillylmandelic acid reflect the composition of adrenergic clones and tumor heterogeneity, we determined urinary DA/noradrenaline and DA/vanillylmandelic acid ratios that presumably reflect DA-beta-hydroxylase (DBH) activity and the prognostic values thereof.

RESULTS

Based on catecholamine metabolism, 4 model situations were defined: (a) complete block of DBH in all cells; (b) block of DBH in some cells; (c) a different enzymatic block; and (d) normal DBH activity in the population of tumor-forming cells. Normal DBH activity was encountered most frequently in children younger than 2 years and in tumors representing favorable prognostic stages (I, II, and IVS). Surviving children with stage IV neuroblastoma presented with tumors composed primarily of cells without the DBH block. Further stratification of 2 prognostically poor groups (stages IV and III + IV) was possible with respect to DBH activity.

CONCLUSIONS

Differential production of neurotransmitters in a population of tumor cells may be explained in terms of tumor heterogeneity.

The value of surgery in directing therapy for patients with Wilms' tumor with pulmonary disease. A report from the National Wilms' Tumor Study Group (National Wilms' Tumor Study 5)

BACKGROUND/PURPOSE

Computed tomography (CT) of the chest with its increased sensitivity frequently identifies lesions not visible on chest radiograph. Treatment of such lesions is controversial. A recent review suggests that patients with Wilms' tumor with pulmonary lesions detected only by CT, who were treated with dactinomycin and vincristine, have an inferior outcome compared with those who also received pulmonary radiation therapy (RT) and doxorubicin. It is important to determine if these small lesions seen only on CT represent metastatic disease and whether patients with these lesions require RT and/or doxorubicin for optimal outcome.

METHODS

Patients with Wilms' tumor with lung metastasis, registered on National Wilms' Tumor Study 5, were reviewed, and those with CT-only lesions who had a radiology and surgical checklist submitted were identified. The treatment regimens of these patients and the histological findings of the pulmonary lesions are presented. We analyzed the pathological findings by whether the patients had single or multiple lesions.

RESULTS

Of 2498 patients registered on National Wilms' Tumor Study 5, 252 had pulmonary metastases. Of these patients, 129 (5.2%) had CT-only lesions (<1 cm). Forty-two of these patients (20 boys and 22 girls) underwent lung biopsy at the discretion of the attending physicians. The local tumor stages in these patients were stage I (7%), II (34%), and III (59%). The treatment stages in these patients were stage I (n = 3, 2 drugs), II (n = 3, 2 drugs), III (n = 12, 3 drugs); and IV (n = 24, 3 drugs + RT). There were 16 patients with isolated lung lesions and 26 with multiple lesions, average size 5.8 +/- 0.5 mm. Of 16 isolated lesions, 13 patients (82%) and 69% (18/26) with multiple lesions had tumor on biopsy. Of the 24 who received RT, 8 had a negative biopsy and, thus, may not have needed the RT. Five of 6 treated with just 2 drugs may have been undertreated. Nine of 12 treated with 3 drugs had tumor on biopsy.

CONCLUSIONS

Computed tomography-only pulmonary lesions are not invariably tumor, demonstrating the need for histopathological confirmation. Biopsy remains critical until radiographic techniques allow differentiation between benign and malignant lesions to optimally direct therapy.

Cytological identification of metastatic epithelial nephroblastoma in pleural fluid: Report of a case and review of literature

Nephroblastoma (Wilms' tumor) is the most common childhood renal tumor and usually presents with a histology and cytology consisting of blastemal, epithelial, and stromal cells. Effusions are not uncommon and may suggest an unfavorable prognosis when containing anaplastic tumor cells. In the present case, we report the cytological appearance of a Wilms' tumor metastatic to the pleura. The effusion consisted primarily of tumor cells demonstrating epithelial differentiation. The tumor cells mostly presented as three-dimensional aggregates in an inflammatory background. Many cystic and tubular structures were identified. The tumor cells demonstrated strong CD56 and WT1 immunoreactivity. The histology of a subsequent surgical specimen reflected the features seen in cytology.

Primary hepatic metastases in nephroblastoma--a report of the SIOP/GPOH Study

PURPOSE

Remarkable progress could be achieved in the treatment of nephroblastoma within the last decades. In all children with Wilms' tumor, 5-year overall survival rate reaches more than 90% in the SIOP/GPOH Study Group. Despite this fact, there is a small group of patients who have tumor lesions in the liver primarily representing a challenge in treatment. Data of this group are analyzed.

METHODS

To define survival and success of treatment in this group of patients, we reviewed the records of 29 of 1365 patients enrolled in the SIOP 93-01/GPOH Study and the SIOP 2001/GPOH Study between April 1, 1994, and September 30, 2004.

RESULTS

Median age at diagnosis was 10.61 years (range, 0.19-34.16 years). All patients but two underwent nephrectomy. Liver metastases were operated in 11 children at time of nephrectomy, in 4 patients secondarily, whereas in 11 patients, liver lesions were treated alone with chemotherapy and radiotherapy, respectively. In 3 children, no treatment could be initiated. Sixteen patients received radiotherapy additionally. Median follow-up was 64 months (range, 3-157 months). Eleven patients died in the course at a median of 13.07 months (range, 0.25-42 months) after initial diagnosis. These included 7 patients who never had surgery for their liver lesions and 4 patients who had incomplete and/or atypical resections of their metastatic liver lesions. All patients who underwent complete resection of hepatic metastases (n = 9) survived. Eight children survived with a nonsurgical treatment. Overall survival was below 60% in the whole group up to now.

CONCLUSIONS

Liver metastases are much less frequent than metastases to other sites. Our report suggests that Wilms' tumor complicated by metastases of the liver primarily has a less favorable outcome. Chemotherapy and radiotherapy play an important role in treatment. Radical surgery for nephrectomy as well as surgery of liver lesions cannot be overemphasized to prevent local and distant recurrence.

Tumor cell-associated neuropilin-1 and vascular endothelial growth factor expression as determinants of tumor growth in neuroblastoma

We sought to characterize the expression of vascular endothelial growth factor (VEGF) and its receptors in neuroblastoma (NBL) and to correlate the results with N-myc (MYCN) expression and in vivo growth of these tumors. Two representative human-derived NBL cell lines, SK-N-AS (AS) with low and SK-N-DZ (DZ) with a high MYCN copy number, were used for the study. We examined their proliferation, VEGF and VEGF receptor expression in vitro and xenograft tumor growth in vivo. In parallel, human NBL specimens were analyzed for expression of VEGF and neuropilin-1 (NRP-1). DZ cells exhibited a 4-fold higher proliferation rate than AS. In contrast, VEGF protein expression was significantly higher in AS cells. NRP-1 was the only VEGF receptor produced in AS and DZ cells in vitro and in vivo. Both AS and DZ cells formed tumors in athymic mice but AS tumors grew 3.5 times larger than DZ tumors and had larger diameter tumor vessels. VEGF and NRP-1 expression was also demonstrated in human NBL specimens. Our studies indicate that VEGF and VEGF receptor expression in NBL tumor cells are associated with tumor growth and that angiogenic factors may serve as a biological marker together with already established MYCN amplification.

Evidence for an age cutoff greater than 365 days for neuroblastoma risk group stratification in the Children's Oncology Group

PURPOSE

In the Children's Oncology Group, risk group assignment for neuroblastoma is critical for therapeutic decisions, and patients are stratified by International Neuroblastoma Staging System stage, MYCN status, ploidy, Shimada histopathology, and diagnosis age. Age less than 365 days has been associated with favorable outcome, but recent studies suggest that older age cutoff may improve prognostic precision.

METHODS

To identify the optimal age cutoff, we retrospectively analyzed data from the Pediatric Oncology Group biology study 9047 and Children's Cancer Group studies 321p1-p4, 3881, 3891, and B973 on 3,666 patients (1986 to 2001) with documented ages and follow-up data. Twenty-seven separate analyses, one for each different age cutoff (adjusting for MYCN and stage), tested age influence on outcome. The cutoff that maximized outcome difference between younger and older patients was selected.

RESULTS

Thirty-seven percent of patients were younger than 365 days, and 64% were > or = 365 days old (4-year event-free survival [EFS] rate +/- SE: 83% +/- 1% [n = 1,339] and 45% +/- 1% [n = 2,327], respectively; P < .0001). Graphical analyses revealed the continuous nature of the prognostic contribution of age to outcome. The optimal 460-day cutoff we selected maximized the outcome difference between younger and older patients. Forty-three percent were younger than 460 days, and 57% were > or = 460 days old (4-year EFS rate +/- SE: 82% +/- 1% [n = 1,589] and 42% +/- 1% [n = 2,077], respectively; P < .0001). Using a 460-day cutoff (assuming stage 4, MYCN-amplified patients remain high-risk), 5% of patients (365 to 460 days: 4-year EFS 92% +/- 3%; n = 135) fell into a lower risk group.

CONCLUSION

The prognostic contribution of age to outcome is continuous in nature. Within clinically relevant risk stratification, statistical support exists for an age cutoff of 460 days.

[Radiologic differentiation of rhabdoid tumor from Wilms' tumor and mesoblastic nephroma]

Differentiation between rhabdoid tumor (RT) and mesoblastic nephroma (MN) and Wilms' tumor (WT) by imaging studies in babies and young children before histological confirmation is useful to start optimal treatment early. Typical radiologic criteria (crescent-shaped subcapsular liquid areas, tumor lobules, blurred tumor borders, metastasis in the lung, and regional lymph nodes) are described. The results of 26 MRI, 30 CT, and 22 ultrasound examinations of 49 patients (22 RT, 19 WT, and 8 MN, age 2-57 months) were analyzed. The above-mentioned radiologic criteria were classified with score values. The score value distribution was analyzed between the tumor entities and by two investigators.RT had significantly higher score values than the MN and WT. The difference between the two investigators was not significant. As a group RT differentiates from the group of WT and MN, but this is not possible in single cases with the radiologic criteria employed. Only if more signs are observed together in one case can a RT be presumed, which may indicate an early biopsy before chemotherapy.

Three-dimensional visualization and virtual simulation of resections in pediatric solid tumors

PURPOSE

Three-dimensional visualization of solid tumors is possible because of high-resolution computed tomography and magnetic resonance imaging scans. However, additional preoperative information is often desirable in complex malignancies. For the first time, the authors present a model of preoperative 3-dimensional visualization and virtual resections in pediatric solid tumors.

METHODS

Image analysis of various pediatric tumors was performed using the research software HepaVision2 (MeVis, Bremen). Organs, tumors, and the vascular system were extracted from multislice computed tomography scans. After hierarchical analysis of the vascular system, territories supplied or drained by the major vascular branches were calculated. Results were explored and virtual resections of organs were carried out using the research software InterventionPlanner (MeVis, Bremen). Data were correlated to intraoperative findings.

RESULTS

Four hepatic malignancies, 4 renal tumors, and 3 other neoplasms were analyzed. The technique of 3-dimensional visualization was feasible for all investigated children (mean age 5 years and 9 months). Spatial relations between physiological and pathological structures were identified, and anatomical structures (vessels, tumor tissue, and organ parenchyma) were determined using colorimetric encoding. Virtual simulations of tumor resection were used successfully for planning of surgical procedures in the hepatic and renal tumors.

CONCLUSIONS

The technique of 3-dimensional tumor visualization and virtual simulation of tumor resections provides the basis for a successful planning of complex tumor resections in children. The efficiency of these techniques should be further analyzed in series with higher numbers and differentiations of tumors.

Quality assessment for Wilms' tumor: a report from the National Wilms' Tumor Study-5

BACKGROUND/PURPOSE

Surgical technique impacts both local tumor stage and risk of local recurrence in Wilms' tumor. A surgical quality assurance program was part of National Wilms' Tumor Study-5 to assess protocol compliance.

METHODS

Surgical checklists, operative, and pathology reports were reviewed concurrently to arrive at the final local tumor stage. If a protocol violation occurred, a letter was sent to the responsible surgeon. Tumor laterality, extent, type of resection, contralateral exploration, node involvement, spills, and local recurrence were reviewed. Relative risk and logistic regression analyses were performed.

RESULTS

There were 1305 nephrectomies. Lymph node sampling was not performed in 117 (9%) patients: stage I, 41 (11.5%), stage II, 57 (12%), and stage III, 19 (4%). Of importance, 41% (187/457) of stage III cases were designated stage III solely on the basis of positive lymph nodes. Tumor spill occurred in 19.3% (253/1305) of children. Fifty-four local spills were in stage II tumors and 97 in stage III. Diffuse spill occurred in 102 patients with stage III tumors. Seventeen preoperative and 13 intraoperative biopsies were performed. Intraoperative tumor rupture was the most common cause of tumor spill accounting for 139 (55%) spills. Nineteen (7.5%) children were upstaged, receiving more intensive therapy because of spill. Included in the group were 3 of 17 preoperative biopsies and 5 of 13 intraoperative biopsies. Spills (13/253) were determined to be avoidable. Eight were biopsies, 5 because tumor was transected in the renal vein (4) or ureter (1). In stage II patients where lymph nodes were not sampled, there is an increase in local relapse rate that did not achieve statistical significance because of the small number of events.

CONCLUSIONS

Although most surgeons complied with the surgical guidelines, numerous deviations were identified including failure to sample lymph nodes (117 cases) and unnecessary biopsies leading to tumor spill (30 cases). Protocol violations have an adverse impact on tumor staging, potentially increasing the risk for local tumor recurrence or intensity and toxicity of therapy.

Familial Wilms tumor

Wilms tumor (WT), an embryonic tumor arising from undifferentiated renal mesenchyme, has been a productive model for understanding the role of genes in both tumorigenesis and normal organogenesis. Approximately 2% of WT patients have a family history of WT, and even sporadic WT is thought to have a strong genetic component to its etiology. Familial WT cases generally have an earlier age of onset and an increased frequency of bilateral disease, although there is variability among WT families, with some families displaying later than average ages at diagnosis. One WT gene, WT1 at 11p13, has been cloned, but only a minority of tumors carry detectable mutations at that locus, and it can be excluded as the predisposition gene in most WT families. Two familial WT genes have been localized, FWT1 at 17q12-q21 and FWT2 at 19q13.4; lack of linkage in some WT families to either of these loci implies the existence of at least one additional familial WT gene. Originally modeled as the inheritance of a mutation in a tumor suppressor gene, molecular analysis of familial tumors not linked to 11p13 have provided data suggesting that this model may be overly simplistic and/or not applicable to all WT families. Identification of the FWT1 and FWT2 genes will help clarify this and will also likely aid in our understanding in general of the roles of the various WT genes and their genetic interactions in the development of WT.

Treatment of neuroblastoma with intraspinal extensions

Neuroblastoma is the most common malignant cause of spinal compression in the paediatric population. Chemotherapy is commonly considered as the first-line treatment for these patients. The role of neurosurgical decompression and radiotherapy are still controversial. Thirteen children diagnosed as having neuroblastoma with intraspinal extension were included in this report. All patients presented with neurological deficits and were treated with chemotherapy initially, after which 3 patients recovered, 4 improved and 6 were aggravated into paraplegia. Two of the 6 aggravated patients received emergent laminectomy with removal of intraspinal tumour and recovered satisfactorily. Although spread of tumour into the spinal canal indicates an advanced disease, aggressive treatments such as chemotherapy and surgical resection can often improve neurological symptoms and life quality. Neurological decompression is recommended for patients with intraspinal neuroblastoma and rapid neurological deterioration during chemotherapy.

Malignant ectomesenchymoma of the orbit in a child: Case report and review of the literature

Malignant ectomesenchymoma is a rare soft tissue tumor of childhood composed of both mesenchymal and neuroectodermal elements. Reported sites of origin are head and neck, abdomen, perineum, scrotum, and extremities. A new case of an orbital ectomesenchymoma in a 7-year-old boy is presented. The clinical picture of the tumor, radiological findings, and its histopathologic and immunohistochemical characteristics are described. The patient was successfully treated with combined surgical resection and chemotherapy. All the other reported cases of malignant ectomesenchymoma with various sites of origin are also reviewed.

Imaging of neuroblastoma and Wilms' tumor

Neuroblastoma and Wilms' tumor are the most common noncentral nervous system solid tumors in children. Imaging plays a crucial role in the evaluation of the primary tumor and regional and metastatic disease. There is a growing body of literature supporting the use of MRI as the technique of choice for the evaluation of local and regional disease in children with suspected neuroblastoma; however, in children with suspected Wilms' tumor, MRI will likely continue to play a role as a problem-solver when the results of CT are equivocal or indeterminant.

Risk-based management of solid tumors in children

BACKGROUND

During the past 25 years significant improvements in survival (56% to 75%) have been observed for children with malignant solid tumors. Multidisciplinary cooperative studies using combined therapy (surgery, chemotherapy, and irradiation) have played a major role. This report describes how recognition of biologic and genetic factors has permitted risk categorization and resulted in new treatment protocols that individualize care.

METHODS

Genetic alterations and biologic factors concerning the multiple endocrine neoplasia syndromes, Wilms' tumor, and neuroblastoma are described.

RESULTS

Using the these data new treatment protocols are designed according to whether a patient is categorized as having a low-, intermediate-, or high-risk tumor, which determines the intensity and type of treatment required.

CONCLUSIONS

Identification of biologic markers and specific gene alterations may be critical in establishing the behavior of tumors (low versus high-risk). Risk-based management permits individualized care for each patient, maximizes survival, minimizes morbidity, and improves the quality of life.