Phase II study of temozolomide and topotecan (TOTEM) in children with relapsed or refractory extracranial and central nervous system tumors including medulloblastoma with post hoc Bayesian analysis: A European ITCC study.

AIM: To assess objective response after two cycles of temozolomide and topotecan (TOTEM) in children with refractory or relapsed miscellaneous extracranial solid and central nervous system (CNS) tumors, including medulloblastoma and primitive neuroectodermal tumors (PNET). PROCEDURE: Multicenter, nonrandomized, phase 2 basket trial including children with solid tumors, completed by a one-stage design confirmatory cohort for medulloblastoma, and an exploratory cohort for PNET. Main eligibility criteria were refractory/relapsed measurable disease and no more than two prior treatment lines. Temozolomide was administered orally at 150 mg/m2 /day followed by topotecan at 0.75 mg/m2 /day intravenously for five consecutive days every 28 days. Tumor response was assessed every two cycles according to WHO criteria and reviewed independently. RESULTS: Thirty-two patients were enrolled and treated in the miscellaneous solid tumor and 33 in the CNS strata; 20 patients with medulloblastoma and six with PNET were included in the expansion cohorts. The median age at inclusion was 10.0 years (range, 0.9-20.9). In the basket cohorts, confirmed complete and partial responses were observed in one glioma, four medulloblastoma, and one PNET, leading to the extension. The overall objective response rate (ORR) in medulloblastoma was 28% (95% CI, 12.7-47.2) with 1/29 complete and 7/29 partial responses, those for PNET 10% (95% CI, 0.3-44.5). Post hoc Bayesian analysis estimates that the true ORR in medulloblastoma is probably between 20% and 30% and below 20% in PNET. The most common treatment-related toxicities of the combination therapy were hematologic. CONCLUSIONS: Temozolomide-topotecan results in significant ORR in children with recurrent and refractory medulloblastoma with a favorable toxicity profile.

Outcome of children with relapsed or refractory neuroblastoma: A meta-analysis of ITCC/SIOPEN European phase II clinical trials.

BACKGROUND: Few randomized trials have been conducted in children with relapsed/refractory neuroblastoma and data about outcomes including progression-free survival (PFS) in these patients are scarce. PROCEDURE: A meta-analysis of three phase II studies of children with relapsed/refractory neuroblastoma conducted in Europe (temozolomide, topotecan-vincristine-doxorubicin and topotecan-temozolomide) was performed. Individual patient data with extended follow-up were collected from the trial databases after publication to describe trial outcomes (response rate, clinical benefit ratio, duration of treatment, PFS, and overall survival [OS]). Characteristics of subjects with relapsed/refractory neuroblastoma were compared. RESULTS: Data from 71 children and adolescents with relapsed/refractory neuroblastoma were collected. Response definitions were not homogeneous in the three trials. Patients were on study for a median of 3.5 months (interquartile range [IQR] 1.9-6.2). Of those, 35.2% achieved a complete or partial response, 26.3% experienced a response after more than two cycles, and 23.9% received more than six cycles. Median PFS from study entry for all, refractory, and relapsed patients was 6.4 ± 1.0, 12.5 ± 6.8, and 5.7 ± 1.0 months, respectively (P = 0.006). Median OS from study entry for all, refractory, and relapsed patients was 16.1 ± 4.3, 27.9 ± 20.2, and 11.0 ± 1.6 months, respectively (P = 0.03). CONCLUSIONS: Baseline data for response rate, clinical benefit ratio, duration of treatment, PFS, and OS were provided. Two subpopulations (relapsed/refractory) were clearly distinct and should be included in the interpretation of all trials. These results should help informing the design of forthcoming studies in relapsed/refractory neuroblastoma.

Long-term side effects of radiotherapy for pediatric localized neuroblastoma : results from clinical trials NB90 and NB94.

INTRODUCTION: Neuroblastoma (NB) is the most frequent indication for extracranial pediatric radiotherapy. As long-term survival of high-risk localized NB has greatly improved, we reviewed treatment-related late toxicities in pediatric patients who received postoperative radiotherapy (RT) for localized NB within two French prospective clinical trials: NB90 and NB94. PATIENTS AND METHODS: From 1990-2000, 610 children were enrolled. Among these, 35 were treated with induction chemotherapy, surgery, and RT. The recommended RT dose was 24 Gy at ≤ 2 years, 34 Gy at > 2 years, ± a 5 Gy boost in both age groups. RESULTS: The 22 patients still alive after 5 years were analyzed. The median follow-up time was 14 years (range 5-21 years). Late effects after therapy occurred in 73 % of patients (16/22), within the RT field for 50 % (11/22). The most frequent in-field effects were musculoskeletal abnormalities (n = 7) that occurred only with doses > 31 Gy/1.5 Gy fraction (p = 0.037). Other effects were endocrine in 3 patients and second malignancies in 2 patients. Four patients presented with multiple in-field late effects only with doses > 31 Gy. CONCLUSION: After a median follow-up of 14 years, late effects with multimodality treatment were frequent. The most frequent effects were musculoskeletal abnormalities and the threshold for their occurrence was 31 Gy.

Long-term results of the combination of the N7 induction chemotherapy and the busulfan-melphalan high dose chemotherapy.

BACKGROUND: To evaluate long-term survival of the first cohort of stage-4 neuroblastoma patients treated with the N7 induction chemotherapy, surgery of the primary tumor and high-dose chemotherapy (HDC) containing Busulfan-Melphalan (Bu-Mel) followed by autologous stem cell transplantation (ASCT). PROCEDURE: From 1998 to 1999, 47 children were included in the NB97 trial and treated with induction chemotherapy according to the N7 protocol, followed by surgery of the primary tumor. HDC (Busulfan, 600 mg/m(2) Melphalan, 140 mg/m(2) ) was administered in patients with partial response of metastases with no more than 3 mIBG spots. Radiotherapy was delivered to the primary tumor site when tumors displayed MYCN amplification. RESULTS: Thirty-nine patients received Bu-Mel (83%): 23 who had achieved complete response (CR) of metastases, 20 after induction treatment and 3 after second-line chemotherapy, and 16 in partial response (PR). The toxicity of the whole treatment was manageable. The main HDC related-toxicity was hepatic veno-occlusive disease grade > 2 occurring in 15% of the patients. The 8-year EFS of the whole cohort was 34% (95% CI, 22-48%). The 8-year EFS of the 39 patients who received Bu-Mel and ASCT was 41% (95% CI, 27-57%). Patients who achieved a CR of metastases at the end of induction chemotherapy had a significantly better outcome than the others (8-year EFS, 52% vs. 20%; P = 0.02). CONCLUSIONS: The long-term results of this first prospective cohort of patients with metastatic disease treated with the N7 induction chemotherapy and HDC (Bu-Mel) confirm published data with stable survival curves but with a longer follow-up.

French multicenter 22-year experience in stem cell transplantation for beta-thalassemia major: lessons and future directions.

Although hematopoietic stem cell transplantation (HSCT) offers curative potential for beta-thalassemia major (beta-TM), it is associated with a variable but significant incidence of graft rejection. We studied the French national experience for improvement over time and the potential benefit of antithymocyte globulin (ATG). Between December 1985 and December 2007, 108 patients with beta-TM underwent HSCT in 21 different French transplantation centers. The majority of patients received a matched sibling transplant (n = 96) and a busulfan- and cyclophosphamide-based conditioning regimen (n = 95), also with ATG in 57 cases. Ninety-five of the 108 patients survived, with a median follow-up of 12 years. Probabilities of 15-year survival and thalassemia-free survival after first HSCT were 86.8% and 69.4%, respectively. Graft failure occurred in 24 patients, 11 of whom underwent a second HSCT. The use of ATG was associated with a decrease in rejection rate from 35% to 10%. Thalassemia-free survival improved significantly with time, reaching 83% in the 54 patients undergoing HSCT after 1994 (median time of HSCT). In view of the increased risk of graft rejection after matched sibling HSCT, current French national guidelines recommend, for all children at risk for beta-TM, the systematic addition of ATG to the myeloablative conditioning regimen and special attention to optimize transfusion and chelation therapy in the pretransplantation period.

Clinical, functional and genetic analysis of twenty-four patients with chronic granulomatous disease - identification of eight novel mutations in CYBB and NCF2 genes.

Chronic granulomatous disease is an inherited disorder in which phagocytes lack a functional NADPH oxidase and cannot produce superoxide anions. The most common form is caused by mutations in CYBB encoding gp91phox. We investigated 24 CGD patients and their families. Twenty-one mutations in CYBB were classified as X91(0), X91(+) or X91(-) variants according to cytochrome b (558) expression. Point mutations in encoding regions represented 50 % of the mutations found in CYBB, splice site mutations 27 %, deletions and insertions 23 %. Eight mutations in CYBB were novel leading to X91(0)CGD cases. Two of these were point mutations: c493G>T and a double mutation c625C>G in exon 6 and c1510C>T in exon 12 leading to a premature stop codon at Gly165 in gp91phox and missense mutations His209Arg/Thr503Ile respectively. Two novel splice mutations in 5'intronic regions of introns 1 and 6 were found. A novel deletion/insertion c1024_1026delCTG/insT results in a frameshift introducing a stop codon at position 346 in gp91phox. The last novel mutation was the insertion of a T at c1373 leading to a frameshift and a premature stop codon at position 484 in gp91phox. For the first time the precise size of two large mutations in CYBB was determined by array-comparative genomic hybridization and carriers' status were evaluated by multiplex ligation-dependent probe amplification assay. No clear correlation between clinical severity and CYBB mutations could be established. Of three mutations in CYBA, NCF1 and NCF2 leading to rare autosomal recessive CGD, one nonsense mutation c29G>A in exon 1 of NCF2 was new.

Late sequelae of symptomatic epidural compression in children with localized neuroblastoma.

BACKGROUND: To describe late sequelae and their correlation with presenting clinical features and tumor treatment in children with symptomatic epidural compression (EC) secondary to localized neuroblastoma. PROCEDURES: A total of 98 evaluable children diagnosed with neuroblastoma and EC, who survived a minimum of 2 years were identified in two Italian and French neuroblastoma series. RESULTS: Symptoms of EC at diagnosis included motor deficit in 94 cases and sphincter deficits in 33. Initial treatment was chemotherapy in 66 cases, neurosurgical decompression in 29 and radiotherapy in 3. Chemotherapy was chosen more frequently for younger children and for those with stage 3 disease. Overall treatment consisted of chemotherapy alone in 44 cases, neurosurgery and chemotherapy in 38, radiotherapy and chemotherapy, with or without neurosurgery, in 16. After a median follow-up of 7.3 years, 57 children (58.2%) had one or more sequelae. Motor sequelae involved 50/57 of these children and correlated with age and severity of motor deficit at diagnosis and neurosurgical treatment. Spine deformities involved 27/57 children and were more frequent in those with severe motor deficit at diagnosis, or who were treated by neurosurgery or radiotherapy. Sphincter dysfunctions involved 31/57 children and were more frequent among children who presented with sphincter symptoms and severe motor deficit. CONCLUSIONS: Fifty-eight percent of the children with localized neuroblastoma and symptomatic EC registered in this study developed late sequelae. The severity of motor deficit at diagnosis was the main risk factor.

A dose-intensive approach (NB96) for induction therapy utilizing sequential high-dose chemotherapy and stem cell rescue in high-risk neuroblastoma in children over 1 year of age.

BACKGROUND: To improve outcome and overall survival (OS) in high-risk neuroblastoma, NB96 induction therapy was intensified using sequential high-dose chemotherapy and autologous stem cell rescue. PROCEDURE: Twenty children were included in this pilot study undertaken at seven reference centers in France, between May 1995 and October 1996. Induction began with one cycle of conventional chemotherapy followed by six sequential cycles of high-dose chemotherapy comprising two cycles of etoposide 800 mg/m(2)/day over 3 days, two cycles of cyclophosphamide 2,000 mg/m(2)/day over 3 days, and two cycles of carboplatin 400 mg/m(2)/day over 5 days, followed by stem cell rescue. RESULTS: Thirteen patients (13/20) received this induction with acceptable toxicity and adequate stem cell harvest. Of these, nine (9/13) underwent surgery according to the protocol, while one patient was given a consolidation regimen prior to surgery. No toxic death was recorded. At the end of induction, complete remission was achieved in 10 cases (50%), with six still alive in July 2009. The 5-year event-free survival and OS were 35 ± 11% and 40 ± 11%, respectively. CONCLUSION: NB96 therapy is feasible and tolerated without lethal toxicity. Nevertheless, given the small sample size and absence of randomization in our study, the effectiveness of this strategy based on metastasis complete response rates and long-term outcome was not superior to other intensive chemotherapy regimens.

Predicting outcomes for children with neuroblastoma using a multigene-expression signature: a retrospective SIOPEN/COG/GPOH study.

BACKGROUND: More accurate prognostic assessment of patients with neuroblastoma is required to better inform the choice of risk-related therapy. The aim of this study is to develop and validate a gene-expression signature to improve outcome prediction. METHODS: 59 genes were selected using an innovative data-mining strategy, and were profiled in the largest neuroblastoma patient series (n=579) to date using real-time quantitative PCR starting from only 20 ng of RNA. A multigene-expression signature was built using 30 training samples, tested on 313 test samples, and subsequently validated in a blind study on an independent set of 236 tumours. FINDINGS: The signature has a performance, sensitivity, and specificity of 85.4% (95% CI 77.7-93.2), 84.4% (66.5-94.1), and 86.5% (81.1-90.6), respectively, to predict patient outcome. Multivariate analysis indicates that the signature is a significant independent predictor of overall survival and progression-free survival after controlling for currently used risk factors: patients with high molecular risk have a higher risk of death from disease and higher risk of relapse or progression than patients with low molecular risk (odds ratio 19.32 [95% CI 6.50-57.43] and 3.96 [1.97-7.97] for overall survival and progression-free survival, respectively, both p<0.0001). Patients at an increased risk of an adverse outcome can also be identified in the current treatment groups, showing the potential of this signature for improved clinical management. These results were confirmed in the validation study, in which the signature was also independently statistically significant in a model adjusted for MYCN status, age, International Neuroblastoma Staging System stage, ploidy, International Neuroblastoma Pathology Classification grade of differentiation, and mitosis karyorrhexis index (odds ratios between 4.81 and 10.53 depending on the model for overall survival and 3.68 [95% CI 2.01-6.71] for progression-free survival). INTERPRETATION: The 59-gene expression signature is an accurate predictor of outcome in patients with neuroblastoma. The signature is an independent risk predictor, identifying patients with an increased risk of poor outcome in the current clinical-risk groups. The method and signature is suitable for routine laboratory testing, and should be evaluated in prospective studies. FUNDING: The Belgian Foundation Against Cancer, the Children Cancer Fund Ghent, the Belgian Society of Paediatric Haematology and Oncology, the Belgian Kid's Fund and the Fondation Nuovo-Soldati (JV), the Fund for Scientific Research Flanders (KDP, JH), the Fund for Scientific Research Flanders, the Institute for the Promotion of Innovation by Science and Technology in Flanders, Strategisch basisonderzoek, the Fondation Fournier Majoie pour l'Innovation, the Instituto Carlos III, the Italian Neuroblastoma Foundation, the European Community under the FP6, and the Belgian programme of Interuniversity Poles of Attraction.

VIP hypersecretion as primary or secondary syndrome in neuroblastoma: A retrospective study by the Société Française des Cancers de l'Enfant (SFCE).

BACKGROUND: Neuroblastic tumors (NTs) are occasionally associated with watery diarrhea, due to Vasoactive Intestinal Peptide (VIP) secretion. Most reports are single cases and suggest a great homogeny within this sub-group of NTs. PROCEDURES: We conducted a retrospective analysis of the French experience of NTs associated with watery diarrhea due to VIP-secretion. VIP secretion was confirmed by seric dosage and/or immunohistochemistry. RESULTS: Twenty-two patients met the diagnostic criteria between 1988 and 2007. Most of patients suffered from weight loss and metabolic disorders. In 16 cases, digestive symptoms preceded the diagnosis of the tumor ("Primary VIP secreting NTs"); 15 were localized and all showed a differentiated histology. Interestingly, in another 6 patients with high-risk NT, diarrhea occurred at the time of chemotherapy or retinoic acid therapy ("Secondary VIP secreting NTs"). Differentiation in response to treatment was documented in 4 cases. In all cases, only surgical excision of the tumor was able to control the digestive symptoms. Twenty children are alive and 13 are disease-free. CONCLUSION: VIP secreting NTs are usually associated with differentiation; they can also secondarily arise from a high-risk tumor upon treatment. Primary surgery constitutes first-line treatment.

Birth-related characteristics, congenital malformation, maternal reproductive history and neuroblastoma: the ESCALE study (SFCE).

Since neuroblastoma occurs very early in children's lives, it has been hypothesized that pre- and perinatal factors may play a role in its etiology. This study investigated the role of birth characteristics, congenital malformation and maternal reproductive history in neuroblastoma. The data used were generated by the national population-based case-control study, ESCALE, conducted in France in 2003-2004. The mothers of 191 neuroblastoma cases and 1,681 controls, frequency-matched by age and gender, were interviewed by telephone, using a standardized questionnaire, on several factors including pregnancy, medical history, lifestyle, childhood medical conditions and exposures. A positive association between congenital malformation and all neuroblastoma cases was observed [Odds ratio (OR) = 2.2, 95% confidence interval (95% CI): 1.1-4.5]. Congenital malformations were highly associated to neuroblastoma in children aged less than 1 year (OR = 16.8, 95% CI: 3.1-90), while no association was observed in children aged 1 year or more (OR = 1.0, 95% CI: 0.3-2.9). A negative association with a maternal history of spontaneous abortions was also found (OR = 0.6, 95% CI: 0.4-0.9). The results strongly support the hypothesis that congenital anomalies may be associated with neuroblastoma, particularly in infant (less than 1 year of age).

Results of induction chemotherapy in children older than 1 year with a stage 4 neuroblastoma treated with the NB 97 French Society of Pediatric Oncology (SFOP) protocol.

PURPOSE: To test the metastatic response rate in stage 4 neuroblastoma, using dose-intensive induction chemotherapy in a multi-institutional setting. PATIENTS AND METHODS: From 1998 to 1999, 47 consecutive children were treated according to N7 protocol. Children received cyclophosphamide 140 mg/kg, doxorubicin 75 mg/m(2), and vincristine 0.066 mg/kg (CAV) in cycles 1, 2, 4, and 6, and cisplatinum 200 mg/m(2) and etoposide 600 mg/m(2) (P/VP) in cycles 3, 5, and 7. The International Neuroblastoma Staging system was used with an emphasis on skeletal evaluation by 123-iodine-metaiodobenzylguanidine (MIBG) scintigraphy. A phase II study evaluating the metastasis complete response rate after induction chemotherapy was conducted in patients who had positive metastatic sites on MIBG scans at diagnosis. RESULTS: Forty-six patients were assessable for toxicity. Hematologic toxicity was the main toxicity observed. Neutropenia was more frequent after CAV than after P/VP (P < .001). A higher rate of thrombocytopenia was observed after P/VP (P = .03). Forty patients with positive MIBG were assessable for metastatic response, and complete regression of metastases was achieved in 17 patients (ie, 43%; 95% CI, 27% to 59%). Of all 47 patients, 21 achieved complete metastatic response. CONCLUSION: The N7 induction chemotherapy protocol was feasible in a multicentric setting. The observed metastasis complete response rate was similar to that obtained in our previous studies and significantly lower than that published in a previous series using the same regimen. In our hands, escalating doses of cyclophosphamide and prolonging conventional chemotherapy with the same drugs failed to improve the metastasis complete response rate.

The pros and cons of split-dose granulocyte colony-stimulating factor alone rather than a single high dose for hematopoietic progenitor cell mobilization in small children (< 15 kg) with solid tumors.

Hematopoietic progenitor cells were mobilized in 34 children with solid tumors weighing < or = 15 kg using granulocyte colony-stimulating factor alone at the doses of 10, 20 or 2 x 12 microg/kg/day. The mobilization with 2 x 12 microg/kg/day was more efficient than that with 10 mg/kg/day. Although the superiority of the split-dose compared to the single, high daily dose (20 microg/kg/day) was not statistically significant, our results suggest that the 2 x 12 microg/kg/day regimen is interesting.

Localized pelvic neuroblastoma: excellent survival and low morbidity with tailored therapy--the 10-year experience of the French Society of Pediatric Oncology.

PURPOSE: To assess the results and morbidity of treatment of children with localized pelvic neuroblastoma (NB). PATIENTS AND METHODS: All consecutive cases of localized pelvic NB registered in the French multicenter prospective studies NBL90 and NBL94 between 1990 and 1999 were reviewed. Resectability was decided on the basis of clinical and radiologic evaluation. In unresectable tumors, primary chemotherapy (combinations of carboplatin-etoposide and vincristine-cyclophosphamide-doxorubicine) was administered before surgery. RESULTS: Forty-seven children (with 26 resectable tumors and 21 unresectable) were included in this study. At the end of treatment, 31 children were in complete remission (66%). Long-term neurologic sequelae were observed in seven patients (15%), directly attributable to surgery in three cases. After a median follow-up of 48 months (range, 13 to 129 months), 44 patients are alive. Six children experienced local relapse; four of these children achieved subsequent remission. The projected overall survival and event-free survival (EFS) rates at 5 years are, respectively, 93% +/- 4% and 84% +/- 5%. Survival of children treated with preoperative chemotherapy are similar to those treated by primary surgery (80% and 88% respectively). The extent of surgical resection seemed to have no influence on the outcome (EFS rates 76% and 89% in case of gross residue and complete resection or microscopic residue, respectively). CONCLUSION: Our data confirm the excellent survival of localized pelvic NBs. Considering the efficacy of preoperative chemotherapy, patients with pelvic NB should be carefully screened for primary surgery. The risk of neurologic impairment during radical excision should be balanced with the good survival of children with minimal residual disease.

Increased risk of systemic relapses associated with bone marrow micrometastasis and circulating tumor cells in localized ewing tumor.

PURPOSE: The presence of metastasis is a major prognostic factor in Ewing tumor (ET). The relapse pattern of patients with localized tumors has long indicated that cases with disseminated ET cells escape detection at diagnosis. ET cells are characterized by specific gene fusions that can be detected with high sensitivity and specificity by reverse transcriptase polymerase chain reaction (RT-PCR). PATIENTS AND METHODS: RT-PCR targeting EWS-FLI-1 or EWS-ERG transcripts was used to search for occult tumor cells in peripheral blood (PB) and bone marrow (BM) at diagnosis in 172 patients with ET, and the prognostic significance of this parameter was assessed. RESULTS: As we suggested previously in a smaller series of patients, RT-PCR positivity of the BM was correlated with a high risk of adverse outcome in the overall study population (P =.007). More interestingly, among patients with otherwise localized tumors, BM micrometastasis also predicted significantly poorer disease-free survival rates (P =.043). The presence of circulating tumor cells (CTC) was more frequently observed in patients with large tumors (P =.006). CTC were associated with a poor outcome among patients with clinically localized disease (P =.045). Patients with clinically localized disease and peripheral occult tumor cells as evidenced by BM and/or PB RT-PCR positivity had axial or proximal tumors and experienced relapses at a systemic rather than at a local level. CONCLUSION: Patients with localized ET and BM micrometastasis or CTC are comparable to patients with metastases in terms of the localization of the primary tumor, outcome, and relapse pattern.

Progression-free survival in children with optic pathway tumors: dependence on age and the quality of the response to chemotherapy--results of the first French prospective study for the French Society of Pediatric Oncology.

PURPOSE: To evaluate a strategy aimed at avoiding radiotherapy during first-line treatment of children with progressive optic pathway tumors (OPT), by exclusively administering multiagent chemotherapy during 16 months. PATIENTS AND METHODS: Between 1990 and 1998, 85 children with progressive OPT were enrolled onto this multicenter nationwide trial. Chemotherapy alternating procarbazine plus carboplatin, etoposide plus cisplatin, and vincristine plus cyclophosphamide was given every 3 weeks. At the time of relapse or progression, second-line chemotherapy was authorized before recourse to radiotherapy. RESULTS: Objective response rate (partial response [PR] + complete response [CR]) to chemotherapy was 42%. Five-year progression-free survival (PFS) and overall survival rates were 34% and 89%, respectively. The 5-year radiotherapy-free survival rate was 61%. In the multivariate analysis of the 85 patients that entered onto the study, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.047) and absence of neurofibromatosis type 1 (P =.035). In the multivariate analysis of the 74 patients that remained on study after the first cycle of chemotherapy, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.0053) and no objective response to chemotherapy (P =.0029). Three-year PFS was 44% in infants < or = 1 year versus 66% in children older than 1 year. Three-year PFS was 53% in the absence of an objective response to chemotherapy versus 68% after a PR or CR. CONCLUSION: A significant proportion of children with OPT can avoid radiotherapy after prolonged chemotherapy. Deferring irradiation with chemotherapy protocols did not compromise overall survival of the entire population or visual function.

Deep Sequencing Reveals Occurrence of Subclonal ALK Mutations in Neuroblastoma at Diagnosis.

PURPOSE: In neuroblastoma, activating ALK receptor tyrosine kinase point mutations play a major role in oncogenesis. We explored the potential occurrence of ALK mutations at a subclonal level using targeted deep sequencing. EXPERIMENTAL DESIGN: In a clinically representative series of 276 diagnostic neuroblastoma samples, exons 23 and 25 of the ALK gene, containing the F1174 and R1275 mutation hotspots, respectively, were resequenced with an extremely high depth of coverage. RESULTS: At the F1174 hotspot (exon 23), mutations were observed in 15 of 277 samples (range of fraction of mutated allele per sample: 0.562%-40.409%). At the R1275 hotspot (exon 25), ALK mutations were detected in 12 of 276 samples (range of fraction of mutated allele: 0.811%-73.001%). Altogether, subclonal events with a mutated allele fraction below 20% were observed in 15/27 ALK-mutated samples. The presence of an ALK mutation was associated with poorer 5-year overall survival (OS: 75% vs. 57%, P = 0.0212 log-rank test), with a strong correlation between F1174 ALK mutations and MYCN amplification being observed. CONCLUSIONS: In this series, deep sequencing allows the detection of F1174 and R1275 ALK mutational events at diagnosis in 10% of cases, with subclonal events in more than half of these, which would have gone undetected by Sanger sequencing. These findings are of clinical importance given the potential role of ALK mutations in clonal evolution and relapse. These findings also demonstrate the importance of deep sequencing techniques for the identification of patients especially when considering targeted therapy.

Phase II study of temozolomide in combination with topotecan (TOTEM) in relapsed or refractory neuroblastoma: a European Innovative Therapies for Children with Cancer-SIOP-European Neuroblastoma study.

PURPOSE: To assess objective response rate (ORR) after two cycles of temozolomide in combination with topotecan (TOTEM) in children with refractory or relapsed neuroblastoma. PATIENTS AND METHODS: This multicenter, non-randomised, phase II study included children with neuroblastoma according to a two-stage Simon design. Eligibility criteria included relapsed or refractory, measurable or metaiodobenzylguanidine (mIBG) evaluable disease, no more than two lines of prior treatment. Temozolomide was administered orally at 150mg/m(2) followed by topotecan at 0.75mg/m(2) intravenously for five consecutive days every 28days. Tumour response was assessed every two cycles according to International Neuroblastoma Response Criteria (INRC), and reviewed independently. RESULTS: Thirty-eight patients were enroled and treated in 15 European centres with a median age of 5.4years. Partial tumour response after two cycles was observed in 7 out of 38 evaluable patients [ORR 18%, 95% confidence interval (CI) 8-34%]. The best ORR whatever the time of evaluation was 24% (95% CI, 11-40%) with a median response duration of 8.5months. Tumour control rate (complete response (CR)+partial response (PR)+mixed response (MR)+stable disease (SD)) was 68% (95% CI, 63-90%). The 12-months Progression-Free and Overall Survival were 42% and 58% respectively. Among 213 treatment cycles (median 4, range 1-12 per patient) the most common treatment-related toxicities were haematologic. Grade 3/4 neutropenia occurred in 62% of courses in 89% of patients, grade 3/4 thrombocytopenia in 47% of courses in 71% of patients; three patients (8%) had febrile neutropenia. CONCLUSION: Temozolomide-Topotecan combination results in very encouraging ORR and tumour control in children with heavily pretreated recurrent and refractory neuroblastoma with favourable toxicity profile.

Phase II study of cisplatin and oral VP16 in patients with refractory or relapsed Ewing sarcoma.

BACKGROUND: Phase II trials demonstrate the activity of cisplatin in patients with refractory Ewing sarcoma family tumours (ESFT) and also the feasibility of giving cisplatin with oral VP16 in a variety of different cancers. This trial was conducted to evaluate the activity and toxicity profile of this combination delivered as outpatient therapy in patients with refractory/relapsed ESFT. METHODS: Cisplatin was administered on days 1, 8 and 15 and days 29, 36 and 43 (70 mg/m(2)/dose for patients <21 years of age and 50 mg/m(2)/dose ≥21 years). VP16 was administered at a dose of 50 mg/m(2) on days 1-15 and days 29-43 inclusive. A three-stage Fleming statistical design was used for analysis. RESULTS: Between January 2003 and October 2006, 45 patients aged between 5 and 46 years (median 19) were enrolled. Thirty-eight were evaluable for response. Patients had previously received one to three lines of chemotherapy (median = one). Seventy-three per cent of the patients had grade 3/4 neutropenia, 20 % developed fever, 40 % had grade 3/4 anaemia, 68 % grade 3/4 thrombocytopenia and 16 % grade 2/3 ototoxicity. Measured response after 2 cycles: 0 CR, 7 PR (18 %), 13 SD (34 %), 18 PD (48 %). There was excellent concordance between unidimensional and bidimensional criteria in 31 of 33 responses (94 %). PFS at 1 year was 39 %, with a median PFS of 6 months. Overall survival at 1 year was 44 %; median survival was 11 months. CONCLUSIONS: Cisplatin combined with oral VP16 is well tolerated and has acceptable side effects, but limited clinical activity in refractory/relapsed ESFT.