High-dose chemotherapy with autologous stem cell rescue followed by posterior fossa irradiation for local medulloblastoma recurrence or progression after conventional chemotherapy

Advancing medulloblastoma therapy: strategies and survival insights

Medulloblastoma, the most common malignant brain tumor in children, presents unique challenges due to its molecular and histological heterogeneity. Advances in molecular profiling have refined risk stratification, enabling personalized treatment strategies and improved survival outcomes. This review synthesizes recent developments in the multimodal management of medulloblastoma, encompassing surgery, craniospinal radiation therapy, and chemotherapy, tailored to patient age and risk classification. Key highlights include subgroup-specific therapies, the role of molecular-targeted treatments, and the integration of genetic testing for germline mutations to guide clinical decision-making. Special emphasis is placed on minimizing treatment-related toxicity while preserving long-term quality of life. Additionally, this manuscript discusses the implications of novel therapeutic approaches for high-risk subgroups, including intensified regimens and systemic therapies for young children. Despite significant progress, challenges remain in addressing long-term complications such as neurocognitive impairments, endocrine dysfunction, and secondary malignancies. Future directions prioritize optimizing therapeutic efficacy while reducing morbidity, underscoring the importance of translating molecular discoveries into clinical practice.

Local and Systemic Therapy of Recurrent Medulloblastomas in Children and Adolescents: Results of the P-HIT-REZ 2005 Study

Simple Summary

A medulloblastoma recurrence is usually associated with an unfavorable prognosis. The German P-HIT-REZ 2005 Study gathered data from patients with relapsed medulloblastomas treated in different, non-randomized therapy arms dependent on preconditions of the patients (previous treatment, comorbidities, relapse pattern), the decision of treating physicians, and the patients’/parents’ choice. A total of 93 evaluable patients with refractory or relapsed medulloblastoma were enrolled. The main aim of this study was to analyze the impact of patient and disease characteristics as well as local and systemic therapies on post-relapse progression-free (PFS) and overall survival (OS). In multivariate analysis, a short time until the first recurrence (<18 months) was the strongest predictor for a worse PFS and OS, which was mainly associated with molecular subgroup 3. Metastatic disease, at relapse, only had a significant impact on OS. Re-biopsy, at relapse, is highly recommended to investigate the histopathological and molecular genetic tumor characteristics and to exclude a secondary malignancy.

Abstract

Recurrent medulloblastomas are associated with survival rates <10%. Adequate multimodal therapy is being discussed as having a major impact on survival. In this study, 93 patients with recurrent medulloblastoma treated in the German P-HIT-REZ 2005 Study were analyzed for survival (PFS, OS) dependent on patient, disease, and treatment characteristics. The median age at the first recurrence was 10.1 years (IQR: 6.9–16.1). Median PFS and OS, at first recurrence, were 7.9 months (CI: 5.7–10.0) and 18.5 months (CI: 13.6–23.5), respectively. Early relapses/progressions (<18 months, n = 30/93) found mainly in molecular subgroup 3 were associated with markedly worse median PFS (HR: 2.34) and OS (HR: 3.26) in regression analyses. A significant survival advantage was found for the use of volume-reducing surgery as well as radiotherapy. Intravenous chemotherapy with carboplatin and etoposide (ivCHT, n = 28/93) showed improved PFS and OS data and the best objective response rate (ORR) was 66.7% compared to oral temozolomide (oCHT, n = 47/93) which was 34.8%. Intraventricular (n = 43) as well as high-dose chemotherapy (n = 17) at first relapse was not related to a significant survival benefit. Although the results are limited due to a non-randomized study design, they may serve as a basis for future treatment decisions in order to improve the patients’ survival.

Bridging the treatment gap in infant medulloblastoma: molecularly informed outcomes of a globally feasible regimen

BACKGROUND

Infant medulloblastoma represents an enormous challenge in neuro-oncology, due to their simultaneous high-risk of recurrence and high risk of severe neurodevelopmental sequelae with craniospinal irradiation. Currently infant medulloblastoma are treated with intensified protocols, either comprising intraventricular methotrexate or autologous transplant, both of which carry significant morbidity and are not feasible in the majority of the world. We sought to evaluate the molecular predictors of outcome in a cohort of infants homogeneously treated with induction chemotherapy, focal radiation and maintenance chemotherapy.

METHODS

In a retrospective analysis, 29 young children treated with a craniospinal irradiation sparing strategy from Hospital Garrahan in Buenos Aires were profiled using Illumina HumanMethylationEPIC arrays, and correlated with survival.

RESULTS

Twenty-nine children (range, 0.3-4.6 y) were identified, comprising 17 sonic hedgehog (SHH), 10 Group 3/4, and 2 non-medulloblastomas. Progression-free survival (PFS) across the entire cohort was 0.704 (95% CI: 0.551-0.899). Analysis by t-distributed stochastic neighbor embedding revealed 3 predominant groups, SHHβ, SHHγ, and Group 3. Survival by subtype was highly prognostic with SHHγ having an excellent 5-year PFS of 100% (95% CI: 0.633-1) and SHHβ having a PFS of 0.56 (95% CI: 0.42-1). Group 3 had a PFS of 0.50 (95% CI: 0.25-1). Assessment of neurocognitive outcome was performed in 11 patients; the majority of survivors fell within the low average to mild intellectual disability, with a median IQ of 73.5.

CONCLUSIONS

We report a globally feasible and effective strategy avoiding craniospinal radiation in the treatment of infant medulloblastoma, including a robust molecular correlation along with neurocognitive outcomes.

Prognostic Clinical and Biologic Features for Overall Survival after Relapse in Childhood Medulloblastoma

Simple Summary

Despite progress in the biology and upfront treatment of childhood medulloblastoma, relapse is almost universally fatal. No standardized treatment has so far been established for these patients. By determining which characteristics are prognostic after relapse, treatment strategies may be optimized for each of these children. We demonstrated that molecular subgroup at diagnosis is a relevant prognostic factor of outcome after relapse. Moreover, we showed that time to relapse and the use of salvage radiotherapy at relapse might have a potential impact on post-relapse survival. Our data suggest that ongoing efforts toward a better understanding of the biology, timing and type of relapse would be important to understand the determinants of tumor behavior at relapse. This could help us address more specific questions on the best surveillance strategies after completion of the treatment and the introduction of risk-stratified second-line treatment strategies.

Abstract

Given the very poor prognosis for children with recurrent medulloblastoma, we aimed to identify prognostic factors for survival post-relapse in children with childhood medulloblastoma. We retrospectively collected clinico-biological data at diagnosis and main clinical characteristics at relapse of children newly diagnosed with a medulloblastoma between 2007 and 2017 at Gustave Roussy and Necker Hospital. At a median follow-up of 6.6 years (range, 0.4–12.3 years), relapse occurred in 48 out 155 patients (31%). The median time from diagnosis to relapse was 14.3 months (range, 1.2–87.2 months). Relapse was local in 9, metastatic in 22 and combined (local and metastatic) in 17 patients. Second-line treatment consisted of chemotherapy in 31 cases, radiotherapy in 9, SHH-inhibitor in four and no treatment in the remaining four. The 1-year overall survival rate post-relapse was 44.8% (CI 95%, 31.5% to 59.0%). While molecular subgrouping at diagnosis was significantly associated with survival post-relapse, the use of radiotherapy at relapse and time to first relapse (>12 months) might also have a potential impact on post-relapse survival.

The impact on outcomes by using thiotepa in tandem transplant for pediatric high-risk embryonal brain tumors

BACKGROUND

Despite aggressive treatment including surgery, radiotherapy, and adjuvant chemotherapy, the outcome of pediatric high-risk embryonal brain tumors remains poor; especially in young children, in whom early radiotherapy inevitably brings significant long-term morbidities. Single or tandem autologous stem cell transplant has been reported to improve outcomes; but optimal use is not well defined.

METHODS

Pediatric patients with high-risk embryonal brain tumors who underwent tandem transplant as consolidation from August 2011 to December 2017 were included. We performed a retrospective chart review and analyzed the outcomes to identify possible prognostic factors.

RESULTS

Eleven pediatric patients with high-risk embryonal brain tumors were enrolled. They received double or triple autologous transplant at complete response in 5 patients and at partial response in 6 for a total of 24 transplants. There were five atypical teratoid rhabdoid tumors, four medulloblastoma, one primitive neuroectodermal tumors, and one pineoblastoma. Median age at diagnosis was 1.8 years (range, 0.6-11.2 years) and at transplant was 2.2 years (range, 1.2-11.9 years). Thiotepa-based regimens were used in 13 cycles of conditioning. All patients achieved successful engraftment. No transplant-related mortality was identified. With a median follow-up of 21.2 months (range, 6.9-51.8 months), seven patients had disease progression. Disease entity and the use of one or more cycles of thiotepa-based regimen during tandem transplant had statistically significant impact on both progression-free survival and overall survival.

CONCLUSION

With successful engraftment and manageable toxicity, tandem transplant in pediatric patients with high-risk embryonal brain tumor is feasible and safe. Patients receiving tandem transplant with one or more cycles of thiotepa-based regimen might have better outcome than those without. In combination with salvage radiotherapy, a favorable 2-year overall survival could be achieved in the majority of patients.

Intellectual, educational, and situation-based social outcome in adult survivors of childhood medulloblastoma

PURPOSE

To investigate intellectual and situation-based social outcome and educational achievement in adult survivors of childhood medulloblastoma and analyse factors influencing outcome Methods: We collected demographic, medical and cognitive data, and social and educational outcome at a mean time since the end of treatments of 14.9 years in 58 adults, aged 19-35 years, consecutively treated in a single cancer center between 1989 and 2005.

RESULTS

Ten survivors had severe intellectual disability, 12 were still studying, 23 had a regular employment and 13 were unemployed. Full Scale Intellectual Quotient, assessed 6.6 years after the end of treatments, ranged from 46 to 131. It was strongly associated with educational achievement and significantly lower in patients who experienced postoperative cerebellar mutism, and when parental education level was low.

CONCLUSION

These factors should be systematically considered at diagnosis in order to offer adequate and timely assessments and interventions.

Childhood Medulloblastoma: Current Therapies, Emerging Molecular Landscape and Newer Therapeutic Insights

Background:

Medulloblastoma is the most common malignant brain tumor in children, currently treated uniformly based on histopathology and clinico-radiological risk stratification leading to unpredictable relapses and therapeutic failures. Identification of molecular subgroups have thrown light on the reasons for these and now reveals clues to profile molecularly based personalized therapy against these tumors.

Methods:

Research and online contents were evaluated for pediatric medulloblastoma which included latest information on the molecular subgroups and their clinical relevance and update on efforts to translate them into clinics.

Results:

Scientific endeavors over the last decade have clearly identified four molecular variants (WNT, SHH, Group 3, and Group 4) and their demographic, genomic, and epigenetic profile. Latest revelations include significant heterogeneity within these subgroups and 12 different subtypes of MB are now identified with disparate outcomes and biology. These findings have important implications for stratification and profiling future clinical trials against these formidable tumors.

Conclusion:

With the continued outpouring of genomic/epigenomic data of these molecular subgroups and evolution of further subtypes in each subgroup, the challenge lies in comprehensive evaluation of these informations. Current and future endeavors are now needed to profile personalized therapy for each child based on the molecular risk stratification of medulloblastoma, with a hope to improve survival outcome and reduce relapses.

High-dose thiotepa-related neurotoxicity and the role of tramadol in children

Background

Serious neurological adverse events (NAE) have occurred during treatment with high-dose thiotepa regimens of children with high-risk solid tumours. The objective was to assess the incidence of NAE related to high-dose thiotepa and to identify potential contributing factors that could exacerbate the occurrence of this neurotoxicity.

Methods

From May 1987 to March 2011, children with solid tumours treated with high-dose thiotepa were retrospectively identified. Each NAE detected led to an independent case analysis. Potential contributing factors were pre-specified and univariate/multivariable analyses were performed.

Results

Three hundred seven courses of thiotepa (251 patients) were identified. The total dose per treatment ranged from 600 to 900 mg/m². 81 NAE (26%) were identified. 46 NAE were related to high-dose thiotepa during the first course (18.3%) and 11 during the second course (19.6%). The symptoms appeared in a median time of 2 days after the introduction of thiotepa. Central and peripheral symptoms were headaches, tremors, confusion, seizures, cerebellar syndrome, and coma. High-dose thiotepa was reintroduced in 18 cases and symptoms reappeared in 5 children. For 3 patients who had seizures during the first course, premedication with clonazepam for the second course has prevented recurrence of NAE. As contributing factors, brain tumour and tramadol treatment increased the risk of thiotepa-related neurotoxicity by 2 to 6 times respectively.

Conclusions

The incidence of neurotoxicity was 18.3%. Brain tumours and tramadol treatment are risk factors to consider when using high-dose thiotepa. The outcome of patients was favourable without sequelae in all cases and rechallenge with thiotepa was possible.

Childhood medulloblastoma

Medulloblastoma accounts for 15-20% of childhood nervous system tumours. The risk of dying was reduced by 30% in the last twenty years. Patients are divided in risk strata according to post-surgical disease, dissemination, histology and some molecular features such as WNT subgroup and MYC status. Sixty to 70% of patients older than 3 years are assigned to the average-risk group. High-risk patients include those with disseminated and/or residual disease, large cell and/or anaplastic histotypes, MYC genes amplification. Current and currently planned clinical trials will: (1) evaluate the feasibility of reducing both the dose of craniospinal irradiation and the volume of the posterior fossa radiotherapy (RT) for those patients at low biologic risk, commonly identified as those having a medulloblastoma of the WNT subgroup; (2) determine whether intensification of chemotherapy (CT) or irradiation can improve outcome in patients with high-risk disease; (3) find target therapies allowing tailored therapies especially for relapsing patients and those with higher biological risk.

Treatment of recurrent primitive neuroectodermal tumors (PNET) in children and adolescents with high-dose chemotherapy (HDC) and stem cell support: results of the HITREZ 97 multicentre trial

Early studies with high-dose chemotherapy for treatment of relapsed cerebral PNET had shown modest efficacy but considerable toxicity. The HIT97 national trial tested a nonrandomized but stratified relapse protocol using either intensive chemotherapy, potentially high dose, or oral chemotherapy. 72 patients (59 disseminated) whose primary treatment had been surgery (97 %), radiotherapy (88 %), and/or chemotherapy (95 %) were enrolled in the intensive chemotherapy arm at diagnosis of relapse or resistance. As a window for this study they received two courses of a 96-hour infusion with carboplatin and etoposide. A response (complete or partial remission) was documented by MRI. Responders received two more cycles of this therapy and stem cell collection, before they received HDC (carboplatin, etoposide, thiotepa) and stem cell support. All possibilities of local therapy were to be explored and applied. After two courses of chemotherapy there was a 52 % response rate (41/72 patients). The median PFS and OS for all 72 patients were 11.6 and 21.1 months. Patients with medulloblastoma had a longer PFS and OS (12.6 and 22.6 months) than those with other PNETs (3.1 and 12.3 months). Favourable prognostic features were no new signs of clinical impairment and localised disease at relapse diagnosis. For the 27 patients who received HDC the median PFS and OS were 8.4 and 20.2 months, respectively. HDC did not benefit patients with resistant cerebral PNET and was associated with profound haematological and mucosal toxicity (90-100 % grade III, IV), infections (50 % grade III and IV) and severe ototoxicity (50 % grade III, 12.5 % grade IV). Treatment related mortality was 8 %. There was low long-term survival and only 2/72 patients are in continuous remission. Adding HDC in patients who responded to the initial courses of chemotherapy did not improve survival. Patients with relapsed cerebral PNET who respond to conventional chemotherapy do not profit from further augmentation to HDC.

High-dose busulfan-thiotepa with autologous stem cell transplantation followed by posterior fossa irradiation in young children with classical or incompletely resected medulloblastoma

BACKGROUND

The aim of the study is to evaluate the outcome of young children with high risk localized medulloblastomas (newly diagnosed classical or incompletely resected) treated by high-dose busulfan-thiotepa with autologous stem cell rescue (ASCT) followed by focal radiation therapy (RT).

PROCEDURE

Between September 1994 and January 2010, 19 children younger than 5 years old at diagnosis fulfilling the above inclusion criteria were treated at the Institute Gustave Roussy. After conventional chemotherapy, they received busulfan at a dose of 600 mg/m(2) and thiotepa at a dose of 900 mg/m(2) followed by ASCT. Focal RT was delivered at least 70 days after ASCT.

RESULTS

The median follow-up was 40.5 months (range, 14.5-191.2 months). The 3-year event-free survival (EFS) and OS were 68% (95% CI 45-84%) and 84% (95% CI 61-94%), respectively. Acute toxicity consisted mainly in hepatic veno-occlusive disease (6/19 patients) and bone marrow aplasia (all patients). No toxic death occurred. The Full Scale Intellectual Quotient tended to decrease over time at a mean rate of 0.9 point per year from the date of diagnosis.

CONCLUSIONS

This intensive treatment resulted in a high overall survival rate in young children with newly diagnosed non-metastatic classic or incompletely resected MB. In spite of a high incidence of hepatic veno-occlusive disease (32%), the acute toxicity was manageable. Delayed neuropsychological side effects remain main concerns. These results should to be confirmed in a larger cohort.

Relapse in medulloblastoma: what can be done after abandoning high-dose chemotherapy? A mono-institutional experience

PURPOSE

We retrospectively report strategies used for medulloblastoma patients progressing after craniospinal irradiation where we aimed for: symptom control, a satisfactory quality of life, accrual in phase 1-2 trials, when available, and the first two conditions could no longer be satisfied by already experienced second-line strategies.

METHODS

Surgery was used in cases of doubtful relapse or when only one site was affected. Radiotherapy was given whenever possible, especially to relieve symptoms. The main chemotherapy regimens were oral temozolomide/etoposide, intravenous (iv.) cisplatin/etoposide, iv. gemcitabine/oxaliplatin, an oral sonic hedgehog pathway inhibitor and oral melphalan.

RESULTS

Between 1998 and 2011, we treated 18 patients relapsed after median 20 months. Nine had relapsed locally, four had dissemination, three single metastases, and two had one synchronous local and metastatic recurrence. Responses to chemotherapy were seen in 32% of cases. The median hospital stay for treatments/complications was 19 days. The 1- and 3-year progression-free survival (PFS) rates were 28 ± 10% and 0%, respectively, for OS, they were 44 ± 12% and 22 ± 10% but no patient was cured. The median PFS after a first relapse was 7 months (range 1-29); the median OS was 7 months (range 4-44). No patients died due to treatment toxicity. Late recurrence (more than 1-2 years after diagnosis) and involvement of single sites were favorable prognostic factors.

CONCLUSIONS

Without succeeding in patients cure, we ensured them further treatment with short hospital stay thus affording low personal and social costs. The chances of cure may emerge from tailored therapies according to genetic stratification.

Relevance of historical therapeutic approaches to the contemporary treatment of pediatric solid tumors

Children with solid tumors, most of which are malignant, have an excellent prognosis when treated on contemporary regimens. These regimens, which incorporate chemotherapeutic agents and treatment modalities used for many decades, have evolved to improve relapse-free survival and reduce long-term toxicity. This review discusses the evolution of the treatment regimens employed for management of the most common solid tumors, emphasizing the similarities between contemporary and historical regimens. These similarities allow the use of historical patient cohorts to identify the late effects of successful therapy and to evaluate remedial interventions for these adverse effects.

Reduced-dose craniospinal radiotherapy followed by tandem high-dose chemotherapy and autologous stem cell transplantation in patients with high-risk medulloblastoma

BACKGROUND

We assessed the feasibility and effectiveness of reduced-dose craniospinal (CS) radiotherapy (RT) followed by tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/autoSCT) in reducing late adverse effects without jeopardizing survival among children with high-risk medulloblastoma (MB).

METHODS

From October 2005 through September 2010, twenty consecutive children aged >3 years with high-risk MB (presence of metastasis and/or postoperative residual tumor >1.5 cm(2)) were assigned to receive 2 cycles of pre-RT chemotherapy, CSRT (23.4 or 30.6 Gy) combined with local RT to the primary site (total 54.0 Gy), and 4 cycles of post-RT chemotherapy followed by tandem HDCT/autoSCT. Carboplatin-thiotepa-etoposide and cyclophosphamide-melphalan regimens were used for the first and second HDCT, respectively.

RESULTS

Of 20 patients with high-risk MB, 17 had metastatic disease and 3 had a postoperative residual tumor >1.5 cm(2) without metastasis. The tumor relapsed/progressed in 4 patients, and 2 patients died of toxicities during the second HDCT/autoSCT. Therefore, 14 patients remained event-free at a median follow-up of 46 months (range, 23-82) from diagnosis. The probability of 5-year event-free survival was 70.0% ± 10.3% for all patients and 70.6% ± 11.1% for patients with metastases. Late adverse effects evaluated at a median of 36 months (range, 12-68) after tandem HDCT/autoSCT were acceptable.

CONCLUSIONS

In children with high-risk MB, CSRT dose might be reduced when accompanied by tandem HDCT/autoSCT without jeopardizing survival. However, longer follow-up is needed to evaluate whether the benefits of reduced-dose CSRT outweigh the long-term risks of tandem HDCT/autoSCT.

Progress from clinical trials and emerging non-conventional therapies for the treatment of Medulloblastomas

Medulloblastomas are highly aggressive tumors of the cerebellum with an embryonal origin. Despite current treatment modalities which include a combination of surgery, chemotherapy and/or radiation, challenges still exist to effectively treat some patients, especially those within the younger age group. In an effort to find improved therapies, ongoing research led by world-wide teams have explored non-conventional therapeutic strategies, as well as examined the efficacy of several drugs in clinical trials among patients with Medulloblastomas. We outline in this article, recent advances on the efficacy and toxicity of numerous therapeutic agents including those that are DNA damaging agents, microtubules binding compounds, and those that are inhibitors of Topoisomerase and of the Notch and Hedgehog signaling pathway, which were assessed in recent Phase I and II clinical trials. Among these clinical trials, it is unfortunate that the outcomes were dismal with the majority of the patients with Medulloblastomas still succumbing to relapse after conventional therapies. Furthermore, it is yet to be established clearly the clinical efficacy of non-conventional therapies such as immunotherapy and gene therapy. Moreover, there is growing interest in proton therapy as a potential replacement for photon therapy, while high dose chemotherapy and autologous stem cell rescue may improve therapeutic efficacies. However, further research is needed to resolve the inherent toxicity from these novel therapeutic methods. In conclusion, novel therapies based on a better understanding of the biology of Medulloblastomas are pivotal in improving non-conventional therapies in the treatment of this deadly disease.

Pseudoprogression after high-dose busulfan-thiotepa with autologous stem cell transplantation and radiation therapy in children with brain tumors: Impact on survival

Children with a brain tumor treated with high-dose busulfan-thiotepa with autologous stem cell transplantation (ASCT) and radiation therapy (RT) often experience radiographic changes during follow-up. The purpose of the study was to identify the incidence, time course, risk factors, and clinical outcome of this complication. From May 1988 through May 2007, 110 patients (median age, 3.6 years; range, 1 month to 15.3 years) with a brain tumor had received 1 course of high-dose busulfan-thiotepa with stem cell rescue, followed or preceded by RT as part of their treatment. All MRI follow-up examinations were systematically reviewed. Twenty-three patients (21%) developed neuroradiological abnormalities at a median time of 9.2 months (range, 5.6-17.3 months) after ASCT. All contrast-enhancing lesions appeared in patients who had received RT after ASCT and were localized inside the 50-55Gy isodoses. They disappeared in 14 of 23 patients after a median time of 8 months (range, 3-17 months), leaving microcalcifications in some cases. The presence of MRI abnormalities was an independent prognostic factor for overall survival in the multivariate analysis (hazard ratio, 0.12; 95% confidence interval [CI], 0.04-0.33), with a 5-year overall survival rate of 84% among patients with MRI abnormalities (95% CI, 62-94), compared with 27% (95% CI, 19-37) among those without lesions. MRI-detectable pseudoprogression is a common early finding in children treated with high-dose busulfan-thiotepa followed by radiation therapy and is correlated with a better outcome.

Spurious progression in pediatric brain tumors

In this study, we sought to characterize post-therapy MRI changes mimicking progression, which we refer to as "spurious progression" (SP) in children with brain tumors. We analyzed whether SP is associated with particular tumor types or therapeutic modalities. Between 2000 and 2009, we identified 181 consecutive children <21 years of age at our center who were treated for brain tumors and had at least three MRI scans within a year after completing therapy. SP was defined as MRI abnormalities characterized by increase in size, enhancement, edema, or cystic changes within 12 months following therapy, and stabilization or improvement on subsequent imaging. One-hundred forty-one patients with brain tumors were evaluable. Fifty-six (40%) had imaging abnormalities initially suggestive of disease progression; of these, 34 (24%) had true disease progression (TP). The remaining 22 (16%) had SP based on either stability, decrease in enhancement, edema, size, or disappearance of these cystic or non-cystic abnormalities. SP occurred in patients with low grade (n = 20) and high grade lesions (n = 2). Median time to SP was 2.4 months (range, 0.7-8.3 months), with time to stability, decrease, or disappearance at a median of 4 months (range 1.4-7.7 months). Five patients were clinically symptomatic from SP and were treated with steroids, cyst drainage, and/or surgery. Therefore, SP occurs more commonly in children with low grade tumors, but can also occur with high grade brain tumors, regardless of therapeutic approach.

Risk-adapted chemotherapy in childhood medulloblastoma

Medulloblastoma is the most common malignant brain tumor in children. The treatment strategy in this tumor mainly includes surgery and radiotherapy, but chemotherapy has been successfully applied in medulloblastoma. The survival rates have improved over the last decade with chemotherapy. The most important prognostic factors were the amount and the extent of metastases, surgery and age. Risk factors have been defined in recent years, but chemotherapy has not been planned according to these defined risk factors on a worldwide basis. The aim of this article was to examine the use of chemotherapy in childhood medulloblastoma according to risk group. A secondary aim was to examine high-dose chemotherapy with autologous stem cell transplantation and the treatment of infant medulloblastoma.

High-dose chemotherapy followed by autologous and allogeneic peripheral blood stem cell transplantation for recurrent disseminated trilateral retinoblastoma

INTRODUCTION

Trilateral retinoblastoma (TRb) is an intracranial neurogenic tumor associated with unilateral or bilateral retinoblastoma and has very poor prognosis. Patients typically die from leptomeningeal tumor dissemination.

CASE REPORT

A 3-year-old girl who had been diagnosed with TRb had a disseminated relapse after a tumorectomy, cerebrospinal irradiation, and conventional chemotherapy. The disseminated tumor disappeared after the first autologous peripheral blood stem cell transplantation (PBSCT) with high-dose melphalan and thiotepa. During the second complete remission, a second autologous PBSCT with high-dose busulfan and melphalan was performed. Seven months after the first PBSCT, the second relapse occurred, and we subsequently performed an allogeneic PBSCT with myeloablative chemotherapy consisting of melphalan, thiotepa, and cyclophosphamide. The patient showed clinical improvement after the allogeneic PBSCT.

CONCLUSION

Although high-dose chemotherapies have a curative effect for some patients with TRb, the prognoses of disseminated tumors are still poor. Further examination of the high-dose chemotherapy is necessary for the time, the conditioning drugs, and the hematopoietic stem cell sources.

[Medulloblastomas: review]

INTRODUCTION

The term of "medulloblastoma" refers to cerebellar tumors belonging to the family of primitive neuro-ectodermic tumors (PNET). Medulloblastomas represent 40% of cerebellar tumors, 15 to 20% of brain tumors and the first cause of malignant brain tumors in childhood. Seventy to 80% of cases are diagnosed in children versus 20 to 30% in adults.

UPDATED KNOWLEDGE

Diagnosis is based on clinical and radiological exams, and proved on pathological analysis in association with molecular biology. Treatment comprises surgery, craniospinal radiotherapy except for children under five years of age and chemotherapy according to age and high-risk criteria. Medulloblastoma is a rare case of a central nervous system tumor which is radio- and chemo-sensitive. Treatment goals are, on one hand, to improve the survival rates and, on the other hand, to avoid late neurocognitive, neuroendocrine and orthopedic side effects related to radiation therapy, notably in children. The prognosis is relatively good, with a five year survival rate over 75% after complete resection of a localized tumor although sequelae may still compromise outcome.

PERSPECTIVES AND CONCLUSION

Management of patients with medulloblastoma implies a multidisciplinary approach combining the contributions of neurosurgery, neuroradiology, pediatric oncology, neuro-oncology and radiotherapy teams.

Interstitial brachytherapy using stereotactic implanted (125)iodine seeds for recurrent medulloblastoma

AIMS

To evaluate the efficacy of interstitial brachytherapy using (125)iodine ((125)I) seeds for the treatment of recurrent multimodal treated medulloblastoma.

MATERIALS AND METHODS

Between September 1989 and August 2009, 12 patients (female:male=3:9, median age 19 years, range 7-55 years) with 23 recurrent medulloblastomas underwent interstitial brachytherapy using (125)I seeds. Before brachytherapy, all patients underwent microsurgical resection; six patients underwent a combined adjuvant treatment consisting of craniospinal irradiation and chemotherapy; three received craniospinal irradiation alone and two received chemotherapy alone. One patient was treated by surgery alone. The median tumour volume was 4.9ml (range 0.4-44.2ml), the median tumour surface dose 50Gy (range 32-50Gy) and the median implantation time 42 days (range 42-90 days). A median follow-up of 26 months was available (range 5-116 months).

RESULTS

After brachytherapy, nine of 23 tumours (39%) presented a complete remission, nine (39%) a partial remission and five (22%) stable disease on magnetic resonance images. The neurological status improved in six patients and remained unchanged in four. Two patients deteriorated: one developed spinal metastasis and another a treatment-related adverse radiation effect. Ten patients died due to disseminated disease despite local tumour control. The median survival after treatment was 15 months (range 5-68 months).

CONCLUSIONS

Our results show a good response of recurrent medulloblastoma after interstitial brachytherapy. High rates of tumour remission were yielded with low rates of treatment-related morbidity. Thus, (125)I seed brachytherapy should be considered as a treatment option for recurrent medulloblastoma.

Childhood medulloblastoma

Among all the childhood central nervous system tumours, medulloblastoma and other neuroectodermal tumours account for 16-25% of cases. The causative factors of medulloblastoma/PNET have not been well established. It is more frequent in boys than in girl and in children than in adults. There was a significant improvement of survival for children diagnosed in 2000-2002 compared to those diagnosed in 1995-1999. The risk of dying was reduced by 30%. Patients are generally divided into risk-stratified schemes on the basis of age, the extent of residual disease, and dissemination. Sixty to 70% of patients older than 3 years are assigned to the average-risk group. High-risk patients include those in the disseminated category, and in North American trials those that have less than a gross or near-total resection, which is arbitrarily defined as 1.5 cm(2) of post-operative residual disease. Current and currently planned clinical trials will:define molecular and biological markers that improve outcome prediction in patients with medulloblastoma and which can be incorporated for front-line stratification of newly defined risk subgroups.

Survival and prognostic factors of early childhood medulloblastoma: an international meta-analysis

PURPOSE

To assess the prognostic role of clinical parameters and histology in early childhood medulloblastoma.

PATIENTS AND METHODS

Clinical and histologic data from 270 children younger than age 5 years diagnosed with medulloblastoma between March 1987 and July 2004 and treated within prospective trials of five national study groups were centrally analyzed.

RESULTS

Two hundred sixty children with medulloblastoma and specified histologic subtype were eligible for analysis (median age, 1.89 years; median follow-up, 8.0 years). Rates for 8-year event-free survival (EFS) and overall survival (OS) were 55% and 76%, respectively, in 108 children with desmoplastic/nodular medulloblastoma (DNMB) or medulloblastoma with extensive nodularity (MBEN); 27% and 42%, respectively, in 145 children with classic medulloblastoma (CMB); and 14% and 14%, respectively, in seven children with large-cell/anaplastic (LC/A) medulloblastoma (P < .001). Histology (DNMB/MBEN: hazard ratio [HR], 0.44; 95% CI, 0.31 to 0.64; LC/A medulloblastoma: HR, 2.27; 95% CI, 0.95 to 5.54; P < .001 compared with CMB), incomplete resection and metastases (M0R1: HR, 1.86; 95% CI, 1.29 to 2.80; M+: HR, 2.28; 95% CI, 1.50 to 3.46; P < .001 compared with M0R0), and national group were independent prognostic factors for EFS, and OS. The HRs for OS ranged from 0.14 for localized M0 and DNMB/MBEN to 13.67 for metastatic LC/A medulloblastoma in different national groups.

CONCLUSION

Our results confirm the high frequency of desmoplastic variants of medulloblastomas in early childhood and histopathology as a strong independent prognostic factor. A controlled de-escalation of treatment may be appropriate for young children with DNMB and MBEN in future clinical trials.

Role of high-dose chemotherapy for recurrent medulloblastoma and other CNS primitive neuroectodermal tumors

We summarize data presented on the use of high-dose chemotherapy (HDCT) with stem cell rescue for patients with recurrent medulloblastoma and other primitive neuroectodermal tumors as presented at an international consensus and state of the art workshop held in Milan in 2006. Eight, mainly institutional, studies were presented that included 159 patients who received HDCT of whom 22% were disease-free survivors at the time of reporting. Of those receiving HDCT and who relapsed having received previous radiotherapy, 17.3% were disease-free survivors at the time of reporting. However, from the two national studies that reported results from the time of relapse, only 4.2% were event free survivors. The outlook for previously irradiated patients with recurrent PNETs remains extremely poor and more effective therapeutic approaches are needed.

Double high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation for primary disseminated medulloblastoma: a report of 3 cases

We performed double high-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) in 3 children with medulloblastoma and primary leptomeningial dissemination, including spinal metastasis. After resection of the main tumor mass, 30.6 Gy whole craniospinal radiation therapy and 4 or 5 courses of conventional chemotherapy with vincristine (1.5 mg/m), carboplatin (560 mg/m), ifosfamide (9000 mg/m), and etoposide (500 mg/m), and 2 courses of high-dose thiotepa (680 mg/m) and melphalan (240 mg/m) therapy with PBSCT were administered. Two patients with low erythroblastic leukemia viral oncogene homolog 2 (ERBB2) gene expression achieved long-term survival (41 mo and 40 mo) but the patient with high ERBB2 expression relapsed 9 months after the second PBSCT.

A case report of pseudoprogression followed by complete remission after proton-beam irradiation for a low-grade glioma in a teenager: the value of dynamic contrast-enhanced MRI

A fourteen years-old boy was treated post-operatively with proton therapy for a recurrent low-grade oligodendroglioma located in the tectal region. Six months after the end of irradiation (RT), a new enhancing lesion appeared within the radiation fields. To differentiate disease progression from radiation-induced changes, dynamic susceptibility contrast-enhanced (DSCE) MRI was used with a T2* sequence to study perfusion and permeability characteristics simultaneously. Typically, the lesion showed hypoperfusion and hyperpermeability compared to the controlateral normal brain. Without additional treatment but a short course of steroids, the image disappeared over a six months period allowing us to conclude for a pseudo-progression. The patient is alive in complete remission more than 2 years post-RT.

No salvage using high-dose chemotherapy plus/minus reirradiation for relapsing previously irradiated medulloblastoma

PURPOSE

Myeloablative regimens were frequently used for medulloblastoma relapsing after craniospinal irradiation (CSI): in 1997-2002, we used repeated surgery, standard-dose and myeloablative chemotherapy, and reirradiation.

METHODS AND MATERIALS

In 10 patients, reinduction included sequential high-dose etoposide, high-dose cyclophosphamide/vincristine, and high-dose carboplatin/vincristine, then two myeloablative courses with high-dose thiotepa (+/- carboplatin); 6 other patients received two of four courses of cisplatin/etoposide. Hematopoietic precursor mobilization followed high-dose etoposide or high-dose cyclophosphamide or cisplatin/etoposide therapy. After the overall chemotherapy program, reirradiation was prescribed when possible.

RESULTS

Seventeen patients were treated: previous treatment included CSI of 19.5-36 Gy with posterior fossa/tumor boost and chemotherapy in 16 patients. Fifteen patients were in their first and 2 in their second and third relapses, respectively. First progression-free survival had lasted a median of 26 months. Relapse sites included leptomeninges in 9 patients, spine in 4 patients, posterior fossa in 3 patients, and brain in 1 patient. Three patients underwent complete resection of recurrence, and 10 underwent reirradiation. Twelve of 14 patients with assessable tumor had an objective response after reinduction; 2 experienced progression and were not given the myeloablative courses. Remission lasted a median of 16 months. Additional relapses appeared in 13 patients continuing the treatment. Fifteen patients died of progression and 1 died of pneumonia 13 months after relapse. The only survivor at 93 months had a single spinal metastasis that was excised and irradiated. Survival for the series as a whole was 11-93 months, with a median of 41 months.

CONCLUSIONS

Despite responses being obtained and ample use of surgery and reirradiation, second-line therapy with myeloablative schedules was not curative, barring a few exceptions. A salvage therapy for medulloblastoma after CSI still needs to be sought.

Risk factors for hepatic veno-occlusive disease: a retrospective unicentric study in 116 children autografted after a high-dose BU-thiotepa regimen

At our Institute, during the last decade, the incidence of hepatic veno-occlusive disease (HVOD) appears to be on the increase among pediatric patients treated with BU-thiotepa (BU-TTP)-conditioning regimen. We thus performed a retrospective analysis to identify the risk factors for HVOD, which could explain such a change. In total, 116 patients treated at Institut Gustave Roussy, between May 1998 and December 2005 were eligible for this study having received BU-TTP as their first high-dose chemotherapy regimen, followed by autologous hematopoietic SCT (AHSCT). According to McDonald's clinical criteria, HVOD was diagnosed in 31% of these children. Demographic, clinical, biological and therapeutic parameters were evaluated in uni- and multivariate analyses that showed a significant correlation between previous carboplatin therapy and risk of developing post transplant HVOD (P=0.028). Comparable results were found for etoposide (P=0.048). In addition, a correlation between HVOD and risk of post transplant death was linked to its association with other types of organ failure (P=0.029). This study demonstrates that previous VPCARBO administration in conventional chemotherapy significantly increases the risk of HVOD among brain tumor patients later consolidated with BU-TTP followed by AHSCT.

Recent development in chemotherapy of paediatric brain tumours

PURPOSE OF REVIEW

Chemotherapy has gained a larger importance in the management of brain tumours, especially in children.

RECENT FINDINGS

Converging results were presented in 2005 by the German, French and North-American cooperative groups indicating that a subgroup of young children with medulloblastoma (i.e. those with desmoplastic histology) could be cured with chemotherapy only strategies. The usefulness of high-dose chemotherapy followed by stem-cell transplant was shown not only as salvage strategy but also upfront in high-risk patients with medulloblastoma. Diffuse pontine glioma remains a devastating disease despite numerous attempts to improve on the standard radiotherapy. Targeted therapies have entered the paediatric neuro-oncology field as well.

SUMMARY

In the most frequent paediatric brain tumors (medulloblastoma and low grade gliomas), the improvements have been impressive in recent years. These patients still await new targeted therapies to lower the burden of treatments and their related side-effects. Most of the brain tumours, however, are rare and the development of specific protocols too slow. Likely, they may have very specific biologic abnormalities that could be efficiently targeted in the near future.