Postoperative neoadjuvant chemotherapy before radiotherapy as compared to immediate radiotherapy followed by maintenance chemotherapy in the treatment of medulloblastoma in childhood: results of the German prospective randomized trial HIT '91

Acute toxicity profile of craniospinal irradiation with intensity-modulated radiation therapy in children with medulloblastoma: A prospective analysis

BACKGROUND

To report on the acute toxicity in children with medulloblastoma undergoing intensity-modulated radiation therapy (IMRT) with daily intrafractionally modulated junctions.

METHODS

Newly diagnosed patients, aged 3-21, with standard-risk (SR) or high-risk (HR) medulloblastoma were eligible. A dose of 23.4 or 36.0 Gy in daily fractions of 1.8 Gy was prescribed to the craniospinal axis, followed by a boost to the primary tumor bed (54 or 55.8 Gy) and metastases (39.6-55.8 Gy), when indicated. Weekly, an intravenous bolus of vincristine was combined for patients with SR medulloblastoma and patients participating in the COG-ACNS-0332 study. Common toxicity criteria (CTC, version 2.0) focusing on skin, alopecia, voice changes, conjunctivitis, anorexia, dysphagia, gastro-intestinal symptoms, headache, fatigue and hematological changes were scored weekly during radiotherapy.

RESULTS

From 2010 to 2014, data from 15 consecutive patients (SR, n = 7; HR, n = 8) were collected. Within 72 h from onset of treatment, vomiting (66 %) and headache (46 %) occurred. During week 3 of treatment, a peak incidence in constipation (33 %) and abdominal pain/cramping (40 %) was observed, but only in the subgroup of patients (n = 9) receiving vincristine (constipation: 56 vs 0 %, P = .04; pain/cramping: 67 vs 0 %, P = .03). At week 6, 73 % of the patients developed faint erythema of the cranial skin with dry desquamation (40 %) or moist desquamation confined to the skin folds of the auricle (33 %). No reaction of the skin overlying the spinal target volume was observed.

CONCLUSIONS

Headache at onset and gastro-intestinal toxicity, especially in patients receiving weekly vincristine, were the major complaints of patients with medulloblastoma undergoing craniospinal irradiation with IMRT.

Metastatic medulloblastoma in adults: outcome of patients treated according to the HIT2000 protocol

BACKGROUND

Due to the rarity of metastatic medulloblastoma in adults, knowledge about the efficacy and toxicity of intensified chemotherapy and radiotherapy is limited.

PATIENTS AND METHODS

Adults with disseminated medulloblastoma registered in the HIT2000 trial as observational patients and treated according to one of two different treatment regimens were analysed. The sandwich strategy MET-HIT2000AB4 consists of postoperative chemotherapy, hyperfractionated craniospinal radiotherapy, and maintenance chemotherapy; while the HIT'91 maintenance strategy consists of postoperative craniospinal radiotherapy, and maintenance chemotherapy.

RESULTS

Twenty-three patients (median age: 30.7years), diagnosed from November 2001 to July 2009, and treated in 18 institutions in Germany and Austria, were eligible. The median follow-up of surviving patients was 3.99years. The 4-year event-free survival (EFS) and overall survival (OS)±standard error (SE) were 52%±12% and 91%±6%, respectively. The survival was similar in both treatment groups (HIT'91 maintenance strategy, n=9; MET-HIT2000AB4 sandwich strategy, n=14). Patients with large cell/anaplastic medulloblastoma relapsed and died (n=2; 4-year EFS/OS: 0%) and OS differed compared to patients with classic (n=11; 4-year EFS/OS: 71%/91%) and desmoplastic medulloblastoma (n=10; 4-year EFS/OS: 48%/100%), respectively (p=0.161 for EFS and p=0.033 for OS). Treatment-induced toxicities consisted mainly of neurotoxicity (50% of patients, ⩾ °II), followed by haematotoxicity and nephrotoxicity/ototoxicity. The professional outcome appeared to be negatively affected in the majority of evaluable patients (9/10).

CONCLUSIONS

Treatment of adults with metastatic medulloblastoma according to the intensified paediatric HIT2000 protocol was feasible with acceptable toxicities. EFS rates achieved by both chemotherapeutic protocols were favourable and appear to be inferior to those obtained in older children/adolescents with metastatic disease.

[Evolution of the management of pediatric and adult medulloblastoma]

Medulloblastoma are cerebellar tumours belonging to the group of primitive neuroectodermal tumours (PNET) and are the most common malignant brain tumours of childhood. These tumours are rare and heterogeneous, requiring some multicentric prospective studies and multidisciplinary care. The classical therapeutic approaches are based on clinical, radiological and surgical data. They involve surgery, radiation therapy and chemotherapy. Some histological features were added to characterize risk. More recently, molecular knowledge has allowed to devise risk-adapted strategies and helped to define groups with good outcome and reduce long-term sequelae, improve the prognostic of high-risk medulloblastoma and develop new therapeutic tools.

Management of pediatric and adult patients with medulloblastoma

OPINION STATEMENT

Approximately 70 % of newly diagnosed children with medulloblastoma (MB) will be classified as "standard risk": their tumor is localized to the posterior fossa, they undergo a near or gross total resection, the tumor does not meet the criteria for large cell/anaplastic histology, and there is no evidence of neuroaxis dissemination by brain/spine MRI and lumbar puncture for cytopathology. Following surgical recovery, they are treated with craniospinal radiation therapy with a boost to the posterior fossa or tumor bed. Adjuvant therapy for approximately 1 year follows anchored by the use of alkylators, platinators, and microtubule inhibitors. This approach to standard risk MB works; greater than 80 % of patients will be cured, and such approaches are arguably the standard of care worldwide for such children. Despite this success, some children with standard risk features will relapse and die of recurrent disease despite aggressive salvage therapy. Moreover, current treatment, even when curative causes life-long morbidity in those who survive, and the consequences are age dependent. For the 20-year-old patient, damage to the cerebellum from surgery conveys greater risk than craniospinal radiation; however, for the 3-year-old patient, the opposite is true. The challenge for the neuro-oncologist today is how to identify accurately patients who need less therapy as well as those for whom current therapy is inadequate. As molecular diagnostics comes of age in brain tumors, the question becomes how to best implement novel methods of risk stratification. Are we able to obtain specific information about the tumor's biology in an increasingly rapid and reliable way, and utilize these findings in the upfront management of these tumors? Precision medicine should allow us to tailor therapy to the specific drivers of each patient's tumor. Regardless of how new approaches are implemented, it is likely that we will no longer be able to have a single standard approach to standard risk medulloblastoma in the near future.

New perspectives in the treatment of adult medulloblastoma in the era of molecular oncology

Medulloblastoma is the most common central nervous system tumor in children, while it is extremely rare in adults. Multimodal treatment involving surgery, radiotherapy and chemotherapy can improve the prognosis of this disease, and recent advances in molecular biology have allowed the identification of molecular subgroups (WNT, SHH, Groups 3 and 4), each of which have different cytogenetic, mutational and gene expression signatures, demographics, histology and prognosis. The present review focuses on the state of the art for adult medulloblastoma treatment and on novel molecular advances and their future implications in the treatment of this disease.

[Germ cell and embryonal tumors]

Germ cell tumors, which constitute approximately 3-5% of tumors of the central nervous system (CNS), can be subdivided into germinomas, embryonal carcinomas, yolk sac tumors, choriocarcinomas, teratomas and mixed germ cell tumors. The diagnosis of intracranial germ cell tumor is based on the clinical symptoms, detection of tumor markers, such as alpha fetoprotein (AFP) and the beta subunit of human chorionic gonadotropin (beta-hCG) in blood and cerebrospinal fluid (CSF), magnetic resonance imaging (MRI) of the brain and spinal cord, CSF cytology and histology. The diagnosis of a secreting germ cell tumor, i.e. a non-germinoma, can be made by the determination of AFP and hCG as tumor markers. Germinomas are radiosensitive but are equally as sensitive to chemotherapy. Teratomas of the CNS are mostly diagnosed in newborns and infants. The most decisive role in the treatment of teratomas is played by as complete a resection as possible. Chemotherapy and irradiation play a subordinate role.Embryonal tumors, which constitute approximately 15-20% of CNS tumors, include medulloblastomas, primitive neuroectodermal tumors (PNET) of the CNS and the atypical teratoid rhabdoid tumor of the CNS. Medulloblastoma is the most common malignant brain tumor in childhood and adolescence. The incidence peak is the fifth year of life with a male predisposition in a ratio of 1.5:1. Medulloblastomas constitute 12-25% of all pediatric CNS tumors and 30-40% of pediatric tumors of the posterior cranial fossa. At the time of diagnosis evidence of dissemination in the CSF cavity is found in approximately 40% of patients. The extreme cell density makes medulloblastomas hyperdense in computed tomography (CT) and can therefore be differentiated from hypodense astrocytomas. The PNETs are histologically related to medulloblastomas, pineoblastomas, atypical teratoid rhabdoid tumors and peripheral neuroblastomas. They are relatively rare in children constituting less than 5% of supratentorial neoplasms. Patients are mostly clinically conspicuous due to macrocephalus and signs of brain pressure and/or seizures. In native CT the solid components of PNETs show a hyperdensity compared to the surrounding brain parenchyma probably due to the high cell density. Cysts and calcification are often detectable. The survival rate of children with CNS tumors has continuously increased in recent years. When corresponding clinical symptoms appear, such as headache, nausea or vomiting when fasting, all of which are evidence of increased intracranial pressure, MRI should be carried out as quickly as possible. Children should be treated in centers with departments of pediatric oncology and hematology and within the framework of studies.

SIOP PODC adapted treatment recommendations for standard-risk medulloblastoma in low and middle income settings

Effective treatment of children with medulloblastoma requires a functioning multi-disciplinary team with adequate neurosurgical, neuroradiological, pathological, radiotherapy and chemotherapy facilities and personnel. In addition the treating centre should have the capacity to effectively screen and manage any tumour and treatment-associated complications. These requirements have made it difficult for many low and middle-income countries (LMIC) centres to offer curative treatment. This article provides management recommendations for children with standard-risk medulloblastoma (localised tumours in children over the age of 3-5 years) according to the level of facilities available.

Subsequent neoplasms in survivors of childhood central nervous system tumors: risk after modern multimodal therapy

BACKGROUND

Multimodal therapy has improved survival for some childhood CNS tumors. However, whether risk for subsequent neoplasms (SNs) also increases is unknown. We report the cumulative incidence of, and risk factors for, SNs after a childhood primary CNS tumor and determine whether treatment that combines radiation therapy (RT) with chemotherapy increases risk for SNs.

METHODS

Analyses included 2779 patients with a primary CNS tumor treated at St Jude Children's Research Hospital between 1985 and 2012. Cumulative incidence and standardized incidence ratios (SIRs) were estimated for SNs confirmed by pathology report. Cumulative incidence among the 237 five-year medulloblastoma survivors treated with multimodal therapy (RT + chemotherapy) was compared with a historical cohort of 139 five-year survivors treated with RT but no chemotherapy in the Childhood Cancer Survivor Study.

RESULTS

Eighty-one survivors had 97 SNs. The cumulative incidence of first SN was 3.0% (95% CI: 2.3%-3.9%) at 10 years, and 6.0% (95% CI: 4.6%-7.7%) at 20 years from diagnosis. Risks were highest for subsequent glioma, all grades (SIR = 57.2; 95% CI: 36.2-85.8) and acute myeloid leukemia (SIR = 31.8; 95% CI: 10.2-74.1). Compared with RT alone, RT + chemotherapy did not increase risk for SNs (hazard ratio: 0.64; 95% CI: 0.38-1.06). Among five-year survivors of medulloblastoma treated with multimodal therapy, cumulative incidence of SN was 12.0% (95% CI: 6.4%-19.5%) at 20 years, no different than survivors treated with RT alone (11.3%, P = .44).

CONCLUSION

The cumulative incidence of SNs continues to increase with time from treatment with no obvious plateau, but the risk does not appear to be higher after exposure to multimodal therapy compared with RT alone. Continued follow-up of survivors as they age is essential.

Chemotherapy for children with medulloblastoma

BACKGROUND

Post-surgical radiotherapy (RT) in combination with chemotherapy is considered as standard of care for medulloblastoma in children. Chemotherapy has been introduced to improve survival and to reduce RT-induced adverse effects. Reduction of RT-induced adverse effects was achieved by deleting (craniospinal) RT in very young children and by diminishing the dose and field to the craniospinal axis and reducing the boost volume to the tumour bed in older children.

OBJECTIVES

PRIMARY OBJECTIVES

1. to determine the event-free survival/disease-free survival (EFS/DFS) and overall survival (OS) in children with medulloblastoma receiving chemotherapy as a part of their primary treatment, as compared with children not receiving chemotherapy as part of their primary treatment; 2. to determine EFS/DFS and OS in children with medulloblastoma receiving standard-dose RT without chemotherapy, as compared with children receiving reduced-dose RT with chemotherapy as their primary treatment.

SECONDARY OBJECTIVES

to determine possible adverse effects of chemotherapy and RT, including long-term adverse effects and effects on quality of life.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2013, Issue 7), MEDLINE/PubMed (1966 to August 2013) and EMBASE/Ovid (1980 to August 2013). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing trial databases (August 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating the above treatments in children (aged 0 to 21 years) with medulloblastoma.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, data extraction and risk of bias assessment. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions. Where possible, we pooled results.

MAIN RESULTS

The search identified seven RCTs, including 1080 children, evaluating treatment including chemotherapy and treatment not including chemotherapy. The meta-analysis of EFS/DFS not including disease progression during therapy as an event in the definition showed a difference in favour of treatment including chemotherapy (hazard ratio (HR) 0.70; 95% confidence interval (CI) 0.54 to 0.91; P value = 0.007; 2 studies; 465 children). However, not including disease progression as an event might not be optimal and the finding was not confirmed in the meta-analysis of EFS/DFS including disease progression during therapy as an event in the definition (HR 1.02; 95% CI 0.70 to 1.47; P value = 0.93; 2 studies; 300 children). Two individual studies using unclear or other definitions of EFS/DFS also showed no clear evidence of difference between treatment arms (one study with unclear definition of DFS: HR 1.67; 95% CI 0.59 to 4.71; P value = 0.34; 48 children; one study with other definition of EFS: HR 0.84; 95% CI 0.58 to 1.21; P value = 0.34; 233 children). In addition, it should be noted that in one of the studies not including disease progression as an event, the difference in DFS only reached statistical significance while the study was running, but due to late relapses in the chemotherapy arm, this significance was no longer evident with longer follow-up. There was no clear evidence of difference in OS between treatment arms (HR 1.06; 95% CI 0.67 to 1.67; P value = 0.80; 4 studies; 332 children). Out of eight reported adverse effects, of which seven were reported in one study, two (severe infections and fever/neutropenia) showed a difference in favour of treatment not including chemotherapy (severe infections: risk ratio (RR) 5.64; 95% CI 1.28 to 24.91; P value = 0.02; fever/neutropenia: RR not calculable; Fisher's exact P value = 0.01). There was no clear evidence of a difference between treatment arms for other adverse effects (acute alopecia: RR 1.00; 95% CI 0.92 to 1.08; P value = 1.00; reduction in intelligence quotient: RR 0.78; 95% CI 0.46 to 1.30; P value = 0.34; secondary malignancies: Fisher's exact P value = 0.5; haematological toxicity: RR 0.54; 95% CI 0.20 to 1.45; P value = 0.22; hepatotoxicity: Fisher's exact P value = 1.00; treatment-related mortality: RR 2.37; 95% CI 0.43 to 12.98; P value = 0.32; 3 studies). Quality of life was not evaluated. In individual studies, the results in subgroups (i.e. younger/older children and high-risk/non-high-risk children) were not univocal.The search found one RCT comparing standard-dose RT with reduced-dose RT plus chemotherapy. There was no clear evidence of a difference in EFS/DFS between groups (HR 1.54; 95% CI 0.81 to 2.94; P value = 0.19; 76 children). The RCT did not evaluate other outcomes and subgroups.The presence of bias could not be ruled out in any of the studies.

AUTHORS' CONCLUSIONS

Based on the evidence identified in this systematic review, a benefit of chemotherapy cannot be excluded, but at this moment we are unable to draw a definitive conclusion regarding treatment with or without chemotherapy. Treatment results must be viewed in the context of the complete therapy (e.g. the effect of surgery and craniospinal RT), and the different chemotherapy protocols used. This systematic review only allowed a conclusion on the concept of treatment, not on the best strategy regarding specific chemotherapeutic agents and radiation dose. Several factors complicated the interpretation of results including the long time span between studies with important changes in treatment in the meantime. 'No evidence of effect', as identified in this review, is not the same as 'evidence of no effect'. The fact that no significant differences between treatment arms were identified could, besides the earlier mentioned reasons, also be the result of low power or too short a follow-up period. Even though RCTs are the highest level of evidence, it should be recognised that data from non-randomised studies are available, for example on the use of chemotherapy only in very young children with promising results for children without metastatic disease. We found only one RCT addressing standard-dose RT without chemotherapy versus reduced-dose RT with chemotherapy, so no definitive conclusions can be made. More high-quality research is needed.

Mir-34a mimics are potential therapeutic agents for p53-mutated and chemo-resistant brain tumour cells

Chemotherapeutic drug resistance and relapse remains a major challenge for paediatric (medulloblastoma) and adult (glioblastoma) brain tumour treatment. Medulloblastoma tumours and cell lines with mutations in the p53 signalling pathway have been shown to be specifically insensitive to DNA damaging agents. The aim of this study was to investigate the potential of triggering cell death in p53 mutated medulloblastoma cells by a direct activation of pro-death signalling downstream of p53 activation. Since non-coding microRNAs (miRNAs) have the ability to fine tune the expression of a variety of target genes, orchestrating multiple downstream effects, we hypothesised that triggering the expression of a p53 target miRNA could induce cell death in chemo-resistant cells. Treatment with etoposide, increased miR-34a levels in a p53-dependent fashion and the level of miR-34a transcription was correlated with the cell sensitivity to etoposide. miR-34a activity was validated by measuring the expression levels of one of its well described target: the NADH dependent sirtuin1 (SIRT1). Whilst drugs directly targeting SIRT1, were potent to trigger cell death at high concentrations only, introduction of synthetic miR-34a mimics was able to induce cell death in p53 mutated medulloblastoma and glioblastoma cell lines. Our results show that the need of a functional p53 signaling pathway can be bypassed by direct activation of miR-34a in brain tumour cells.

Treatment developments and the unfolding of the quality of life discussion in childhood medulloblastoma: a review

PURPOSE

To describe how the quality of life (QOL) discussion in childhood medulloblastoma (MB) relates to treatment developments, survival and sequelae from 1920 to 2014.

METHODS

Articles containing "childhood medulloblastoma" and "quality of life" were identified in PubMed. Those containing phrases pertaining to psychological, emotional, behavioral or social adjustment in the title, abstract or keywords were selected. Inclusion of relevant older publications was assured by cross-checking references.

RESULTS

1920-1930s: suction, electro-surgery, kilovolt (KV) irradiation. Survival = months. Focus on operative mortality, symptoms and survival. 1940s: radiotherapy improved. 1950s: chemotherapy and intubation. Survival = years. Opinions oscillated between optimism/awareness of physical sequelae of radiotherapy. 1960s: magnified vision, ventriculo-peritoneal (VP) shunts, megavolt (MV) irradiation. Long-term survival shifted the attention towards neurological problems, disability and carcinogenesis of radiotherapy. 1970s: CT, microscope, bipolar coagulation, shunt filters, neuroanesthesia, chemotherapy trials and staging studies. Operative mortality decreased and many patients (re)entered school; emphasis on neuropsychological sequelae, IQ and academic performance. 1980s: magnetic resonance imaging (MRI), Cavitron ultrasonic aspiration (CUSA), laser surgery, hyper-fractionated radiotherapy (HFRT). Cerebellar mutism, psychological and social issues. 1990s: pediatric neurosurgery, proton beams, stem cell rescue. Reflections on QOL as such. 21st century: molecular genetics. Premature aging, patterns of decline, risk- and resilience factors.

DISCUSSION

QOL is a critical outcome measure. Focus depends on survival and sequelae, determined after years of follow-up. Detailed measurements are limited by time, money and human resources, and self-reporting questionnaires represent a crude measure limited by subjectivity. Therapeutic improvements raise the question of QOL versus cure. QOL is a potential primary research endpoint; multicenter international studies are needed, as are web-based tools that work across cultures.

Kinetics of porphyrin fluorescence accumulation in pediatric brain tumor cells incubated in 5-aminolevulinic acid

BACKGROUND

Fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) enables more complete resections of tumors in adults. 5-ALA elicits accumulation of fluorescent porphyrins in various cancerous tissues, which can be visualized using a modified neurosurgical microscope with blue light. Although this technique is well established in adults, it has not been investigated systematically in pediatric brain tumors. Specifically, it is unknown how quickly, how long, and to what extent various pediatric tumors accumulate fluorescence. The purpose of this study was to determine utility and time course of 5-ALA-induced fluorescence in typical pediatric brain tumors in vitro.

METHODS

Cell cultures of medulloblastoma [DAOY and UW228], cPNET [PFSK] atypical teratoid rhabdoid tumor [BT16] and ependymoma [RES196] were incubated with 5-ALA for either 60 minutes or continuously. Porphyrin fluorescence intensities were determined using a fluorescence-activated cell sorter (FACS) after 1, 3, 6, 9, 12 and 24 hours. C6 and U87 cells served as controls.

RESULTS

All pediatric brain tumor cell lines displayed fluorescence compared to their respective controls without 5-ALA (p < 0.05). Sixty minutes of incubation resulted in peaks between 3 and 6 hours, whereas continuous incubation resulted in peaks at 12 hours or beyond. 60 minute incubation peak levels were between 52 and 91 % of maxima achieved with continuous incubation. Accumulation and clearance varied between cell types.

CONCLUSIONS

We demonstrate that 5-ALA exposure of cell lines derived from typical pediatric central nervous system (CNS) tumors induces accumulation of fluorescent porphyrins. Differences in uptake and clearance indicate that different application modes may be necessary for fluorescence-guided resection, depending on tumor type.

Overcoming multiple drug resistance mechanisms in medulloblastoma

INTRODUCTION

Medulloblastoma (MB) is the most common malignant paediatric brain tumour. Recurrence and progression of disease occurs in 15-20% of standard risk and 30-40% of high risk patients. We analysed whether circumvention of chemoresistance pathways (drug export, DNA repair and apoptotic inhibition) can restore chemotherapeutic efficacy in a panel of MB cell lines.

RESULTS

We demonstrate, by immunohistochemistry in patient tissue microarrays, that ABCB1 is expressed in 43% of tumours and is significantly associated with high-risk. We show that ABCB1, O6-methylguanine-DNA-methyltransferase (MGMT) and BCL2 family members are differentially expressed (by quantitative reverse transcription polymerase chain reaction, Western blotting and flow cytometry) in MB cell lines. Based on these findings, each pathway was then inhibited or circumvented and cell survival assessed using clonogenic assays. Inhibition of ABCB1 using vardenafil or verapamil resulted in a significant increase in sensitivity to etoposide in ABCB1-expressing MB cell lines. Sensitivity to temozolomide (TMZ) was MGMT-dependent, but two novel imidazotetrazine derivatives (N-3 sulfoxide and N-3 propargyl TMZ analogues) demonstrated ≥7 fold and ≥3 fold more potent cytotoxicity respectively compared to TMZ in MGMT-expressing MB cell lines. Activity of the BAD mimetic ABT-737 was BCL2A1 and ABCB1 dependent, whereas the pan-BCL2 inhibitor obatoclax was effective as a single cytotoxic agent irrespective of MCL1, BCL2, BCL2A1, or ABCB1 expression.

CONCLUSIONS

ABCB1 is associated with high-risk MB; hence, inhibition of ABCB1 by vardenafil may represent a valid approach in these patients. Imidazotetrazine analogues of TMZ and the BH3 mimetic obatoclax are promising clinical candidates in drug resistant MB tumours expressing MGMT and BCL2 anti-apoptotic members respectively.

Hyperfractionated Accelerated Radiotherapy (HART) with maintenance chemotherapy for metastatic (M1-3) Medulloblastoma--a safety/feasibility study

BACKGROUND AND PURPOSE

To evaluate feasibility and toxicity of Hyperfractionated Accelerated Radiotherapy (HART) 1.24Gy b.i.d. followed by chemotherapy for M1-3 Medulloblastoma (MB). The aim of HART was to use hyperfractionation to improve therapeutic ratio combined with acceleration to minimise tumour cell repopulation during radiotherapy (RT).

MATERIALS AND METHODS

Between February 2002 and May 2008, 34 eligible patients (22 male, 12 female) aged 3-15years (median 7) with metastatic MB (M1-9; M2-3, M3-22) received HART with a craniospinal radiotherapy (CSRT) dose of 39.68Gy followed by 22.32Gy boost to the whole posterior fossa and 9.92Gy metastatic boosts. The 8th and subsequent patients received vincristine (VCR) 1.5mg/m(2) weekly×8 doses over 8weeks starting during the 1st week of RT. Maintenance chemotherapy comprised 8 six-weekly cycles of VCR 1.5mg/m(2) weekly×3, CCNU 75mg/m(2) and cisplatin 70mg/m(2).

RESULTS

Median duration of HART was 34days (range 31-38). Grade 3-4 toxicities included mucositis (8), nausea (10), anaemia (5), thrombocytopaenia (2), leucopaenia (24). With 4.5-year median follow-up, 3-year EFS and OS were 59% and 71%, respectively. Of 10 relapses, 1 was outside the central nervous system (CNS), 1 posterior fossa alone and 8 leptomeningeal with 3 also associated with posterior fossa.

CONCLUSION

HART with or without VCR was well tolerated and may have a place in the multi-modality management of high-risk MB.

Long-term outcomes and role of chemotherapy in adults with newly diagnosed medulloblastoma

OBJECTIVE

To assess the survival and role of adjuvant chemotherapy in adult medulloblastoma.

METHODS

We reviewed outcomes of 66 patients (aged 18 y or more; median age, 33 y) with medulloblastoma. Forty-four (67%) patients had M0 disease, 9 had M1-M4, and 13 had MX. Thirty-one patients each for whom risk stratification was available were classified as high risk or standard risk. Fifty-six patients had histologic results: classic histology was the most common (n=46 [84%]), followed by desmoplastic (n=9), and large cell/anaplastic (n=1). Overall survival (OS) and progression-free survival (PFS) were estimated with Kaplan-Meier curves and log-rank tests. Cox regression analysis was used to compare recurrences.

RESULTS

Median follow-up was 6.7 years. The estimated 5-year OS and PFS were 74% and 59%, respectively. High-risk versus standard-risk classification was associated with worse OS (61% vs. 86%; P=0.03) and recurrence (hazard ratio, 2.56; P=0.05) and a trend for worse PFS (49% vs. 69%; P=0.13). Gross total resection was associated with improved OS (P=0.03) and a trend toward improved PFS (P=0.09). No chemotherapy benefit could be demonstrated for the group as a whole. For high-risk patients with classic histology (n=25), chemotherapy was associated with a trend for improvement in 5-year PFS from 36% to 71% (P=0.10) and in 5-year OS from 49% to 100% (P=0.08).

CONCLUSIONS

In adult patients with medulloblastoma, the extent of resection and risk classification predicts the outcome. These results suggest a chemotherapy benefit for high-risk patients with classic histology.

Medulloblastoma Down Under 2013: a report from the third annual meeting of the International Medulloblastoma Working Group

Medulloblastoma is curable in approximately 70 % of patients. Over the past decade, progress in improving survival using conventional therapies has stalled, resulting in reduced quality of life due to treatment-related side effects, which are a major concern in survivors. The vast amount of genomic and molecular data generated over the last 5–10 years encourages optimism that improved risk stratification and new molecular targets will improve outcomes. It is now clear that medulloblastoma is not a single-disease entity, but instead consists of at least four distinct molecular subgroups: WNT/Wingless, Sonic Hedgehog, Group 3, and Group 4. The Medulloblastoma Down Under 2013 meeting, which convened at Bunker Bay, Australia, brought together 50 leading clinicians and scientists. The 2-day agenda included focused sessions on pathology and molecular stratification, genomics and mouse models, high-throughput drug screening, and clinical trial design. The meeting established a global action plan to translate novel biologic insights and drug targeting into treatment regimens to improve outcomes. A consensus was reached in several key areas, with the most important being that a novel classification scheme for medulloblastoma based on the four molecular subgroups, as well as histopathologic features, should be presented for consideration in the upcoming fifth edition of the World Health Organization’s classification of tumours of the central nervous system. Three other notable areas of agreement were as follows: (1) to establish a central repository of annotated mouse models that are readily accessible and freely available to the international research community; (2) to institute common eligibility criteria between the Children’s Oncology Group and the International Society of Paediatric Oncology Europe and initiate joint or parallel clinical trials; (3) to share preliminary high-throughput screening data across discovery labs to hasten the development of novel therapeutics. Medulloblastoma Down Under 2013 was an effective forum for meaningful discussion, which resulted in enhancing international collaborative clinical and translational research of this rare disease. This template could be applied to other fields to devise global action plans addressing all aspects of a disease, from improved disease classification, treatment stratification, and drug targeting to superior treatment regimens to be assessed in cooperative international clinical trials.

Technique, outcomes, and acute toxicities in adults treated with proton beam craniospinal irradiation

BACKGROUND

Proton craniospinal irradiation (p-CSI) has been proposed to reduce side effects associated with CSI. We evaluated acute toxicities and preliminary clinical outcomes in a series of adults treated with p-CSI.

METHODS

We reviewed medical records for 50 patients (aged 16-63 y) with malignancies of varying histologies treated consecutively with vertebral body-sparing p-CSI at MD Anderson Cancer Center from 2007 to 2011. Median CSI and total boost doses were 30.6 and 54 Gy. Forty patients received chemotherapy, varying by histology. Median follow-up was 20.1 months (range, 0.3-59).

RESULTS

Median doses to the thyroid gland, pituitary gland, hypothalamus, and cochleae were 0.003 Gy-relative biological effectiveness (RBE; range, 0.001-8.5), 36.1 Gy-RBE (22.5-53.0), 37.1 Gy-RBE (22.3-54.4), and 33.9 Gy-RBE (22.2-52.4), respectively. Median percent weight loss during CSI was 1.6% (range, 10% weight loss to 14% weight gain). Mild nausea/vomiting was common (grade 1 = 46%, grade 2 = 20%); however, only 5 patients experienced grade ≥2 anorexia (weight loss >5% baseline weight). Median percent baseline white blood cells, hemoglobin, and platelets at nadir were 52% (range, 13%-100%), 97% (65%-112%), and 61% (10%-270%), respectively. Four patients developed grade ≥3 cytopenias. Overall and progression-free survival rates were 96% and 82%, respectively, at 2 years and 84% and 68% at 5 years.

CONCLUSIONS

This large series of patients treated with p-CSI confirms low rates of acute toxicity, consistent with dosimetric models. Vertebral body-sparing p-CSI is feasible and should be considered as a way to reduce acute gastrointestinal and hematologic toxicity in adults requiring CSI.

High-risk medulloblastoma: a pediatric oncology group randomized trial of chemotherapy before or after radiation therapy (POG 9031)

PURPOSE

To compare event-free survival (EFS) in children with high-risk medulloblastoma randomly assigned to receive either chemotherapy before radiation or chemotherapy after radiation.

PATIENTS AND METHODS

One hundred twelve patients were randomly assigned to each arm. Criteria used to categorize patients as high risk included M1-4 disease by modified Chang staging classification, T3b/T4 disease, or greater than 1.5 cm3 of residual tumor after surgery. Postoperatively, children with high-risk medulloblastoma were randomly assigned to two arms, either chemotherapy entailing three cycles of cisplatin and etoposide before radiation (chemotherapy first [CT1]) or the same chemotherapy regimen after radiation (radiation therapy first [RT1]). Both groups received consolidation chemotherapy consisting of vincristine and cyclophosphamide.

RESULTS

The median follow-up time was 6.4 years. Five-year EFS was 66.0% in the CT1 arm and 70.0% in the RT1 arm (P = .54), and 5-year overall survival in the two groups was 73.1% and 76.1%, respectively (P = .47). In the CT1 arm, 40 of the 62 patients with residual disease achieved either complete or partial remission.

CONCLUSION

Five-year EFS did not differ significantly whether, after surgery, patients received chemotherapy before or after radiotherapy.

Long-term tumor-free survival case of congenital embryonal tumor with various pathological components

PURPOSE

Treatment strategy of malignant congenital brain tumor is controversial. We report a congenital embryonal tumor case with various pathological components.

METHODS

A normally delivered male infant had an enlarged head circumference at 1 month after birth. The abnormality of the right side of the head was also noted during the routine 4-month health check. The head circumference was 45.1 cm (+2.25, SD); neurological status, however, was normal, with a pediatric GCS of 9 and body weight of 6,370 g (-0.85, SD). Magnetic resonance imaging (MRI) revealed right brain tumor whose size was 99 × 91 × 86 mm. The tumor was enhanced homogeneously with central necrosis, and the margin of the tumor was well circumscribed.

RESULTS

We performed a subtotal removal of the tumor. The pathological diagnosis was meningioma (MIB-1 index was 2 %). The residual tumor gradually shrank, and we performed monthly MRI follow-up. The tumor abruptly recurred 7 months after the operation. The level of patient consciousness deteriorated, and emergency removal surgery was performed. The histological examination showed various types of embryonal components without meningioma-like parts. The pathological diagnosis was an embryonal tumor. The MIB-1 index was 48 %. One month after the second operation, dissemination of the tumor occurred at the right temporal lobe, cerebellum, and in subcutaneous tissue. Chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide) was initiated following radiation therapy (3 Gy/day, 8×). Adjuvant therapies were effective, and no tumor recurrence was detected during 34 months follow-up.

CONCLUSION

Treatment strategies for malignant indefinite diagnosed tumor need to be discussed.

Detection of irreversible changes in susceptibility-weighted images after whole-brain irradiation of children

INTRODUCTION

Whole-brain irradiation is part of the therapy protocol for patients with medulloblastomas. Side effects and complications of radiation can be detected by follow-up magnetic resonance imaging (MRI). Susceptibility-weighted images (SWI) can detect even very small amounts of residual blood that cannot be shown with conventional MRI. The purpose of this study was to determine when and where SWI lesions appear after whole-brain irradiation.

METHODS

MRI follow-up of seven patients with medulloblastoma who were treated with whole-brain irradiation were analyzed retrospectively. SWI were part of the initial and follow-up MRI protocol. De novo SWI lesions, localization, and development over time were documented.

RESULTS

At time of irradiation, mean age of the patients was 13 years (±4 years). Earliest SWI lesions were detected 4 months after radiation treatment. In all patients, SWI lesions accumulated over time, although the individual number of SWI lesions varied. No specific dissemination of SWI lesions was observed.

CONCLUSION

Whole-brain irradiation can cause relatively early dot-like SWI lesions. The lesions are irreversible and accumulate over time. Histopathological correlation and clinical impact of these SWI lesions should be investigated.

A multi-center phase Ib study of oxaliplatin (NSC#266046) in combination with fluorouracil and leucovorin in pediatric patients with advanced solid tumors

BACKGROUND

Platinum agents have been used for a variety of cancers, including pivotal use in pediatric tumors for many years. Oxaliplatin, a third generation platinum, has a different side effect profile and may provide improved activity in pediatric cancers.

PROCEDURE

Patients 21 years or younger with progressive or refractory malignant solid tumors, including tumors of the central nervous system were enrolled on this multi-center open label, non-randomized Phase 1 dose escalation study. The study used a standard 3 + 3 dose escalation design with 2 dose levels (85 and 100 mg/m(2) ) with an expansion cohort of 15 additional patients at the recommended dose. Patients received oxaliplatin at the assigned dose level and 5-fluorouracil (5-FU) bolus 400 mg/m(2) followed by a 46-hour 5-FU infusion of 2,400 mg/m(2) every 14 days. The leucovorin dose was fixed at 400 mg/m(2) for all cohorts.

RESULTS

Thirty-one evaluable patients were enrolled, 8 at 85 mg/m(2) and 23 at 100 mg/m(2) for a total of 121 courses. The median age was 12 years (range 2-19 years). The main toxicities were hematologic, primarily neutrophils and platelets. The most common non-hematologic toxicities were gastrointestinal. Stable disease was noted in 11 patients (54% of evaluable patients) and 1 confirmed partial response in a patient with osteosarcoma.

CONCLUSIONS

The maximum planned dose of oxaliplatin at 100 mg/m(2) per dose in combination with 5-FU and leucovorin was safe and well tolerated and in this patient population. This combination demonstrated modest activity in patients with refractory or relapsed solid tumor and warrants further study. Pediatr Blood Cancer 2013;60:230-236. © 2012 Wiley Periodicals, Inc.

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.

Survival and secondary tumors in children with medulloblastoma receiving radiotherapy and adjuvant chemotherapy: results of Children's Oncology Group trial A9961

The purpose of the trial was to determine the survival and incidence of secondary tumors in children with medulloblastoma receiving radiotherapy plus chemotherapy. Three hundred seventy-nine eligible patients with nondisseminated medulloblastoma between the ages of 3 and 21 years were treated with 2340 cGy of craniospinal and 5580 cGy of posterior fossa irradiation. Patients were randomized between postradiation cisplatin and vincristine plus either CCNU or cyclophosphamide. Survival, pattern of relapse, and occurrence of secondary tumors were assessed. Five- and 10-year event-free survivals were 81 ± 2% and 75.8 ± 2.3%; overall survivals were 87 ± 1.8% and 81.3 ± 2.1%. Event-free survival was not impacted by chemotherapeutic regimen, sex, race, age at diagnosis, or gender. Seven patients had disease relapse beyond 5 years after diagnosis; relapse was local in 4 patients, local plus supratentorial in 2, and supratentorial alone in 1. Fifteen patients experienced secondary tumors as a first event at a median time of 5.8 years after diagnosis (11 >5 y postdiagnosis). All non-CNS solid secondary tumors (4) occurred in regions that had received radiation. Of the 6 high-grade gliomas, 5 occurred >5 years postdiagnosis. The estimated cumulative 10-year incidence rate of secondary malignancies was 4.2% (1.9%-6.5%). Few patients with medulloblastoma will relapse ≥ 5 years postdiagnosis; relapse will occur predominantly at the primary tumor site. Patients are at risk for development of secondary tumors, many of which are malignant gliomas. This may become an increasing issue as more children survive.

Medulloblastoma

OPINION STATEMENT

The mainstay of medulloblastoma treatment is high-quality interdisciplinary collaboration in diagnosis, treatment, and aftercare by all involved disciplines. The first step in treatment of medulloblastoma is a maximal safe surgery, followed by thorough staging. Surgery should only be performed in experienced neurosurgical centers, with age-appropriate postoperative care. As optimal risk stratification is based on histopathological and neuroradiological assessments, these should be performed or confirmed by experienced specialists. Central review of histopathological subtype, as well as review of staging evaluations is highly desirable. For young children with desmoplastic/nodular (DMB), or extensive nodular medulloblastoma, craniospinal or any radiotherapy should be avoided. For young children with classic medulloblastoma (CMB), large cell, or anaplastic medulloblastoma (LC/A MB) optimized strategies with high-dose chemotherapy and autologous stem cell rescue with or without local radiotherapy are under investigation. For older clinical standard risk patients (without metastases, without postoperative residual tumor >1.5 cm(2)) with CMB or DMB, craniospinal radiotherapy with 23.4 Gy and boost to the posterior fossa to 54 Gy, followed by maintenance chemotherapy can be regarded as a standard therapy besides other currently applied regimen, such as the use of intensified chemotherapy after irradiation. Older children with LC/A MB, metastatic medulloblastoma, and/or large residual tumor can be regarded as high-risk patients and should receive intensified treatment: intensified chemotherapeutic regimen before or after radiotherapy with increased dose (36-Gy CSI normofractionated, or 40-Gy hyperfractionated) is used. For treatment to be effective, quality control of radiotherapy is of high relevance. Information on long-term sequelae is essential and appropriate multidisciplinary follow-up and support, including rehabilitation and help for reintegration, is necessary. Whenever possible, patients should be included in prospective studies, and tumor material should be sampled to facilitate further research on medulloblastoma biology, which will significantly influence the stratification criteria and the introduction of targeted therapies in standard treatment recommendations in the future.

Hyperfractionated Versus Conventional Radiotherapy Followed by Chemotherapy in Standard-Risk Medulloblastoma: Results From the Randomized Multicenter HIT-SIOP PNET 4 Trial

Purpose

To compare event-free survival (EFS), overall survival (OS), pattern of relapse, and hearing loss in children with standard-risk medulloblastoma treated by postoperative hyperfractionated or conventionally fractionated radiotherapy followed by maintenance chemotherapy.

Patients and Methods

In all, 340 children age 4 to 21 years from 122 European centers were postoperatively staged and randomly assigned to treatment with hyperfractionated radiotherapy (HFRT) or standard (conventional) fractionated radiotherapy (STRT) followed by a common chemotherapy regimen consisting of eight cycles of cisplatin, lomustine, and vincristine.

Results

After a median follow-up of 4.8 years (range, 0.1 to 8.3 years), survival rates were not significantly different between the two treatment arms: 5-year EFS was 77% ± 4% in the STRT group and 78% ± 4% in the HFRT group; corresponding 5-year OS was 87% ± 3% and 85% ± 3%, respectively. A postoperative residual tumor of more than 1.5 cm2 was the strongest negative prognostic factor. EFS of children with all reference assessments and no large residual tumor was 82% ± 2% at 5 years. Patients with a delay of more than 7 weeks to the start of RT had a worse prognosis. Severe hearing loss was not significantly different for the two treatment arms at follow-up.

Conclusion

In this large randomized European study, which enrolled patients with standard-risk medulloblastoma from more than 100 centers, excellent survival rates were achieved in patients without a large postoperative residual tumor and without RT treatment delays. EFS and OS for HFRT was not superior to STRT, which therefore remains standard of care in this disease.

Concurrent cyclophosphamide and craniospinal radiotherapy for pediatric high-risk embryonal brain tumors

Embryonal tumors are an aggressive subtype of high-grade, pediatric central nervous system (CNS) tumors often with dismal survival rates. The 5-year survival for highest-risk embryonal tumors may be as low as 10 %. We report feasibility and efficacy from our experience using intravenous (IV) cyclophosphamide concurrently with craniospinal radiation (CSI) in high-risk embryonal CNS tumors of childhood. Ten consecutive children (aged: 3.5-15.5 years, median: 10.2 years, six male) with high-risk embryonal tumors, including: large cell/anaplastic medulloblastoma (6), atypical teratoid rhabdoid tumor (1), and leptomeningeal primitive neuroectodermal tumor (3), were treated with IV cyclophosphamide 1 g/M(2) on days 1 and 2 of CSI. Following a median of 36 Gy CSI plus tumor boosts, adjuvant treatment consisted of 21 doses of oral etoposide (7) and alkylator based chemotherapy from five to eight cycles in all. Of the ten patients thus treated, six remain alive with no evidence of disease and four are deceased. Median survival was 3.3 years, with a 3-year progression-free survival of 50 % (5/10). Median follow-up was: 3.3 years (range: 5 months-12.9 years) in the five patients with progression, median time-to-progression was: 1.3 years (range: 1 month-3 years). Median follow-up in the patients without progression is 8.8 years (range: 3-12.9 years). Complications due to adjuvant chemotherapy were typical and included myelosupression (10), necessitating shortened duration of chemotherapy in three, and hemorrhagic cystitis (1). In high-risk embryonal CNS tumors, cyclophosphamide given concurrently with CSI is well tolerated. Early results suggest that a phase II trial is warranted.

Highly cited German research contributions to the fields of radiation oncology, biology, and physics: focus on collaboration and diversity

BACKGROUND AND PURPOSE

Tight budgets and increasing competition for research funding pose challenges for highly specialized medical disciplines such as radiation oncology. Therefore, a systematic review was performed of successfully completed research that had a high impact on clinical practice. These data might be helpful when preparing new projects.

METHODS

Different measures of impact, visibility, and quality of published research are available, each with its own pros and cons. For this study, the article citation rate was chosen (minimum 15 citations per year on average). Highly cited German contributions to the fields of radiation oncology, biology, and physics (published between 1990 and 2010) were identified from the Scopus database.

RESULTS

Between 1990 and 2010, 106 articles published in 44 scientific journals met the citation requirement. The median average of yearly citations was 21 (maximum 167, minimum 15). All articles with ≥ 40 citations per year were published between 2003 and 2009, consistent with the assumption that the citation rate gradually increases for up to 2 years after publication. Most citations per year were recorded for meta-analyses and randomized phase III trials, which typically were performed by collaborative groups.

CONCLUSION

A large variety of clinical radiotherapy, biology, and physics topics achieved high numbers of citations. However, areas such as quality of life and side effects, palliative radiotherapy, and radiotherapy for nonmalignant disorders were underrepresented. Efforts to increase their visibility might be warranted.

Outcome of children with metastatic medulloblastoma treated with carboplatin during craniospinal radiotherapy: a Children's Oncology Group Phase I/II study

PURPOSE

We evaluated the feasibility of administering carboplatin as a radiosensitizer during craniospinal radiation therapy (CSRT) to patients with high-risk medulloblastomas (MBs) and supratentorial primitive neuroectodermal tumors, and we report the outcome in the subset with metastatic (M+) MB.

PATIENTS AND METHODS

After surgery, patients received 36 Gy CSRT with boosts to sites of disease. During radiation, patients received 15 to 30 doses of carboplatin (30-45 mg/m(2)/dose), along with vincristine (VCR) once per week for 6 weeks. Patients on regimen A received 6 months of maintenance chemotherapy (MC) with cyclophosphamide and VCR. Once the recommended phase II dose (RP2D) of carboplatin was determined, cisplatin was added to the MC (regimen B).

RESULTS

In all, 161 eligible patients (median age, 8.7 years; range, 3.1 to 21.6 years) were enrolled. Myelosuppression was dose limiting and 35 mg/m(2)/dose × 30 was determined to be the RP2D of carboplatin. Twenty-nine (36%) of 81 patients with M+ MB had diffuse anaplasia. Four patients were taken off study within 11 months of completing radiotherapy for presumed metastatic progression and are long-term survivors following palliative chemotherapy. Excluding these four patients, 5-year overall survival ± SE and progression-free survival ± SE for M+ patients treated at the RP2D on regimen A was 82% ± 9% and 71% ± 11% versus 68% ± 10% and 59% ± 10% on regimen B (P = .36). There was no difference in survival by M stage. Anaplasia was a negative predictor of outcome.

CONCLUSION

The use of carboplatin as a radiosensitizer is a promising strategy for patients with M+ MB. Early progression should be confirmed by biopsy.

Medulloblastoma/Primitive neuroectodermal tumor and germ cell tumors: the uncommon but potentially curable primary brain tumors

This article presents an overview of medulloblastomas, central nervous system primitive neuroectodermal tumors, and germ cell tumors for the practicing oncologist. Discussion includes the definition of these tumors, histopathologic findings, molecular and genetic characteristics, prognoses, and evolution of treatment.

Long-term results of combined preradiation chemotherapy and age-tailored radiotherapy doses for childhood medulloblastoma

To reduce the sequelae of craniospinal irradiation (CSI) in children under 10 (≥3) years old and to improve the prognosis for high-risk medulloblastoma in adolescents, we adjusted postoperative chemotherapy and CSI doses to patients' stage and age. From 1986 to 1995, 73 patients entered the study. Children under 10 and adolescents with metastases, residual disease (RD) or stage >T3 received postoperative IV vincristine and high-dose (HD) ± intrathecal (IT) methotrexate, while standard-risk adolescents were given IV vincristine and IT methotrexate. Chemotherapy was followed by CSI (19.8 Gy for children <10; 36 Gy for adolescents), with a 54-Gy posterior fossa boost. Maintenance chemotherapy with lomustine and vincristine was administered for a year afterwards. A total of 39 children were under 10 of whom 20 had metastases. Response to chemotherapy was recorded in 70%, but 5-year EFS and OS were only 48 and 56%, respectively. Results were significantly worse for metastatic cases, patients under 10, those with RD, and those staged without MRI (unavailable early in the study). Efforts to preserve survivors' quality of life did not pay off, and most patients over 30 still depended on their parents' income and had severe cognitive/endocrine disabilities. In conclusion, despite a very high response rate with this preradiation HD methotrexate schedule, the outcome for high-risk medulloblastoma patients did not improve (especially when lower CSI doses were used) and patients still developed severe morbidities.

Progressive hearing loss after completion of cisplatin chemotherapy is common and more pronounced in children without spontaneous otoacoustic emissions before chemotherapy

OBJECTIVE

High frequency hearing loss following cisplatin chemotherapy is frequent in children and often necessitates the fitting of hearing aids. During therapy, hearing is usually monitored. Post-therapeutic follow-up does not routinely include monitoring of hearing, although there are indications that hearing thresholds can decline after therapy.

METHODS

Pure-tone audiograms taken from 27 children (17 males, 10 females) treated with cisplatin at Muenster university hospital (mean age 9.84 years, standard deviation 3.67 years) including an audiological follow-up at least 6 months after therapy, were analyzed retrospectively.

RESULTS

In follow-up tests after completion of therapy, 24.1% of all ears showed an increase in mean high frequency hearing thresholds (4-8 kHz). Post-therapeutic hearing deterioration was significant at 4 kHz and significantly more pronounced in children without measurable spontaneous otoacoustic emissions (SOAE) before therapy. Post-therapeutic hearing deterioration did not occur in ears with normal pure tone thresholds (≤ 10dB at all frequencies) after cisplatin therapy. No correlation was found between post-therapeutic hearing deterioration and cranial irradiation.

CONCLUSIONS

Cisplatin chemotherapy follow-up should include audiological monitoring in all children with elevated pure tone thresholds after therapy. Routine SOAE measurements taken as part of baseline audiometry before the start of chemotherapy can be taken into consideration.

Medulloblastomas: update on a heterogeneous disease

PURPOSE OF REVIEW

Medulloblastoma is the main primitive neuroectodermal tumour of the posterior fossa in childhood. The classical therapeutic approach consists of surgical resection, followed by craniospinal irradiation. Because of the good overall survival (75%), the main recent research efforts focus on refining the most relevant prognostic stratification and in decreasing the long-term sequelae.

RECENT FINDINGS

Thanks to the better understanding of the heterogeneity of medulloblastomas, clinical, histological and biological markers have been clearly identified and allow risk-adapted strategies. A subset of tumours of early childhood (<3-5 years), frequently associated with a Sonic Hedgehog signalling, might be cured without irradiation. In older children, several trials have demonstrated the safety of reduced craniospinal irradiation in standard risk tumours. Furthermore, the evidence of an excellent prognosis associated with a subset of tumours characterized by an activation of the WNT pathway leads to forthcoming de-escalating strategies. Reducing long-term sequelae also relies on new surgical approaches aiming at reducing the cerebellar injuries. Tremendous efforts have also been made in defining the most adapted irradiation doses and fields. Intensity-modulated radiotherapy and proton beam therapy might also influence the long-term neurological and endocrine defects of the patients.

SUMMARY

Histological and biological characteristics clearly define various prognostic groups within medulloblastomas; confirming the overall good outcome and reducing long-term sequelae are the main focus of current clinical trials.

Urgent radiotherapy is effective in the treatment of metastatic medulloblastoma causing symptomatic brainstem edema

A 3-year-old male who presented with hydrocephalus symptoms was found to have metastatic medulloblastoma with diffuse spinal disease. Thirteen days following surgical resection of his primary tumor, he clinically deteriorated due to worsening brainstem edema. Following intubation, stress-dose steroids, and mannitol, urgent radiotherapy was initiated to the whole brain and cervical cord. The patient improved clinically with a repeat MRI showing decreased leptomeningeal enhancement in the radiation fields. In the literature, there are no reports of successful urgent radiotherapy in medulloblastoma, but in this instance, it proved to be a viable option.

Appraisal of the current staging system for residual medulloblastoma by volumetric analysis

AIM

This study aims to investigate the accuracy of the current staging system of childhood medulloblastoma by using volumetric image analysis on immediate post-operative MRI scans.

MATERIAL AND METHODS

Tumour volume and maximum cross area of residual medulloblastoma were measured on immediate post-operative MR scans of 37 children operated between 1999 and 2005.

RESULTS

Mean preoperative volume was 32 cm(3) (range 4.5-71.9 cm(3)). Mean post-operative volume was 3.3 cm(3) (range 0-23.3 cm(3)). At mean follow-up of 50.08 months (range 6-129), 15 (40%) patients had died. Cut-off limit for residual post-operative tumour volume employed was maximum cross section of 1.5 cm(2), which corresponds to volume of 1.376 cm(3); 14 patients (38%) had no residual tumour, 7 patients (19%) had less than 1.5 cm(2) and 16 patients (43%) had more than 1.5 cm(2) residual tumour in its maximum cross section area. In three patients (8.2%) there was mismatch between the measured maximum cross section area and volume. In particular, in two patients, the cross section areas were more than 1.5 cm(2) but the residual tumour volumes were less than 1.376 cm(3) (the cross section area overestimated the residual volume) and in one case, the cross section area was less than 1.5 cm(2) but the residual tumour volume was more than 1.376 cm(3) (the cross section area underestimated the residual volume; difference statistically significant, Fisher's exact test, p < 0.01).

CONCLUSIONS

It appears that volumetric measurement of residual medulloblastoma on immediate post-operative MRI scans may further improve the accuracy of staging process.