Abstract Background Posterior Fossa Syndrome/Cerebellar Mutism Syndrome (PFS/CMS) is a serious surgical complication that causes severely debilitating long-term deficits in communication, motor function and cognition in affected children. Despite emerging evidence that injury to efferent cerebellar pathways may account for the wide variety of symptoms observed in PFS/CMS, the underlying pathophysiology remains poorly understood. Here, we aim to identify critical structures that are frequently affected in PFS/CMS using multivariate lesion symptom mapping. Methods Early postoperative cerebellar lesions were analyzed in 154 children with midline intraventricular medulloblastoma from a German medulloblastoma series. 52 children developed postoperative PFS/CMS (34%) defined as complete mutism (PFS1, 41/52) or the inability to string 3-word sentences (PFS2, 11/52). Lesions were manually segmented and defined as new T2-FLAIR hyperintensities surrounding the surgical cavity, reflecting surgery-related tissue damage. Lesion maps were transformed into MNI-152 space using a customized pipeline. Sparse canonical correlation analysis for neuroimaging (SCCAN) was conducted to identify patterns of surgical damage associated with PFS/CMS. 47/154 patients underwent follow-up neuropsychological testing. The surgical approach to tumor resection was evaluated from surgical reports. Results SCCAN identified a pattern of surgical damage significantly associated with PFS/CMS (r=.35, p<.001) with peak voxel weights in the right superior cerebellar peduncle, vermal lobule VI and left lobule IX. PFS/CMS was associated with reduced processing speed (β = −.42, p=.006) and fine motor skills (Purdue Pegboard dominant hand: β = −.42, p=.011; non-dominant hand: β = −.48, p=.004). Vermian incision was not associated with an increased risk for PFS/CMS (OR = 1.78, p=.204). Conclusion Our findings suggest that surgical damage to the cerebellar outflow pathways and superior vermis is associated with PFS/CMS, potentially implicating disrupted cerebello-cortical communication. Surgical techniques that minimize damage to these structures may reduce the incidence and severity of PFS/CMS in the future.

Choroid plexus papilloma (CPP) and atypical choroid plexus papilloma (aCPP) have excellent outcomes. However, some CPP/aCPP relapse and may qualify for postoperative adjuvant treatment. German patients from the International CPT-SIOP Registry diagnosed with CPP/aCPP between 2011 and 2023 were included and analysed according to initial staging (postoperative residual tumor [R+], metastases [M+]), biology, postoperative treatment strategy and outcome. Additionally, patients from the published CPT-SIOP-2000 trial (PMID34997889) were combined with the registry cohort for validation purpose. Ninety-three patients were identified (male: n = 53, female: n = 40). Median age at diagnosis was 1.9 (0.1–17.6) years. Initial staging was R0/M0 in n = 61, R+/M0 in n = 24, R0/M + in n = 5 and R+/M + in n = 3. aCPP was diagnosed in n = 38 patients. Molecular subgroup was available for n = 36: ”adult” n = 3, “pediatric A” n = 21 and “pediatric B” n = 12 (6/12 aCPP). Median follow-up was 5.5 (± 0.99) years. Twelve tumors relapsed: R0/M0 n = 4, R+/M0 n = 7, R+/M + n = 1. One patient with relapse died. Most patients did not receive postoperative treatment (n = 88). Five patients (R0/M + n = 2; R+/M + n = 1; R0/M0 n = 2) received postoperative chemotherapy. None was irradiated during first-line treatment. In the enlarged cohort (n = 197), histological diagnosis had a significant impact on PFS (5y-PFS: CPP 90 ± 3.1, aCPP 78.6 ± 4.6, PFS = 0.01). Both, R+ (5y-PFS: R0 90.6 ± 2.6, R + 69.1 ± 7.0, PFS = 0.01) as well as molecular subgroup “pediatric B” (5y-PFS: pediatric A 95.2

PURPOSE:European Reference Networks (ERN) are collaborative networks connecting healthcare professionals across Europe. A virtual multidisciplinary tumor board (VMTB) for children with central nervous system (CNS) tumors was established within the ERN for pediatric oncology (ERN PaedCan) in 2022. We report the experience with this new format. METHODS:A web-based questionnaire was distributed to physicians for cases presented between November 2022 and November 2023, addressing the implementation of provided recommendations, satisfaction and basic data about the local institution. Baseline information of the presented cases was taken from anonymized VMTB protocols. RESULTS:In the first year, 19 patients from 11 institutions located in nine European countries were discussed in 21 VMTB. The German national reference center for neuroradiology demonstrated MRI findings in 19/21 (91%) conferences. 19 questionnaires were answered by physicians from all participating countries. Main reason for VMTB presentation were questions about therapy (79%). Presenting institutions treated a median of 10 (5-150) neuro-oncological pediatric patients per year. All hospitals conducted own institutional tumor boards. National central review was available in 3/9 countries (33%). Recommendations were followed, at least partly, in all except one patient experiencing unexpected clinical deterioration. Recommendations were considered helpful in 90%. All participants would recommend the VMTB to colleagues. Technical issues regarding data provision were reported as the main obstacle in 56%. CONCLUSION:A European VMTB for pediatric patients with CNS tumors is feasible and perceived as useful by the participants. Recommendations were followed frequently. Optimization of privacy-compliant data exchange is crucial for continuance of the format.

BACKGROUND:Childhood cancer remains a significant psychological burden for parents. Even after end of treatment, parents of childhood cancer survivors remain at high risk of developing anxiety and depression. However, knowledge about the prevalence and changes of these conditions post-treatment is limited. AIMS:This study aimed to assess the proportion of parents exhibiting clinically relevant symptoms of anxiety and/or depression, explore gender differences, examine factors associated with these conditions and their longitudinal data. METHODS:Five hundred and sixteen parents of childhood cancer survivors (aged 0-17 years at diagnosis of leukemia or central nervous system tumors) were evaluated after treatment and again 12-18 months later. Anxiety (GAD-7) and depression (PHQ-9) symptoms were assessed. Generalized linear mixed models were used to analyze factors influencing these conditions and their changes. RESULTS:At baseline, 30% of parents reported clinically relevant depression, and 34% reported anxiety, both decreasing to 16% at follow-up. Mothers reported higher anxiety and depression scores, with more meeting clinically relevant thresholds. Low family functioning, psychotherapy, physical illness, and a recent diagnosis were significant predictors of both conditions. Additional predictors for depression included unemployment, single-parent status, and fear of progression, while female gender was a predictor for anxiety in the final model. Greater symptom improvements were associated with higher baseline symptoms, whereas longer time since diagnosis was linked to less improvement. CONCLUSION:Anxiety and depression represent significant burdens for parents of childhood cancer survivors, with several modifiable risk factors identified. Targeted psychosocial support, early screening, and tailored interventions may reduce distress and improve family well-being.

Ependymomas are tumors of glial origin representing the second most common malignant brain tumors of childhood. Peak incidence in childhood is under 3 years of age. Most paediatric ependymomas arise intracranially and are molecularly divided into four groups, namely supratentorial ependymoma, ZFTA fusion-positive (ST-ZFTA), supratentorial ependymoma, YAP1 fusion-positive (ST-YAP1), posterior fossa group A (PF-A), and posterior fossa group B (PF-B) ependymoma. Spinal ependymomas in children are rare. An integrated diagnosis requires a combination of histological and molecular features as well as tumour localization. Staging with pre- and early post-surgery magnetic resonance imaging of the neuraxis, accompanied by cerebrospinal fluid (CSF) analysis 14 days post surgery must be performed. CSF at primary surgery is highly recommended to both detect and inform biomarkers. Patients should ideally be treated in specialized centers and, whenever possible, within a prospective clinical trial. Molecular classification has become increasingly important and will be applied to enable patient stratification in upcoming clinical trials. However, there are not yet specific treatment recommendations for distinct molecular groups. Apart from the molecular group, the extent of neurosurgical resection is the most consistent prognostic factor. Therefore, the feasibility of second-look surgery targeting complete resection should always be evaluated if residual disease. Adjuvant radiotherapy has been shown to be effective in consolidating local control and is therefore recommended following complete resection. Focal radiotherapy is the standard of care for patients with non-disseminated ependymoma, and craniospinal radiotherapy is recommended in older children with metastatic disease. For very young children with metastatic disease, radiotherapy avoidance strategies using systemic therapy is recommended to reduce the risk of neurocognitive effects. Highly conformal techniques such as proton beam therapy or intensity-modulated radiation therapy are preferred. Chemotherapy bridging therapy may be applied until patients reach 12–18 months of age, or to facilitate complete resections where further surgery is planned.

Purpose Currently, the different types of ependymal neoplasm (EPN) are defined by anatomical localization and genetics. This retrospective multicenter study aimed to analyze the imaging patterns of both local and distant recurrences in supratentorial (ST) and posterior fossa (PF) EPN. Methods We exclusively evaluated patients with recurrent EPN. To form the basis for follow-up evaluations the imaging characteristics for ST-EPN and PF-EPN were assessed and compared to each other. Follow-up assessments included the idenTIFFication of local recurrent tumors, leptomeningeal dissemination, secondary intraparenchymal lesions, and extraneural metastases. MR-signal characteristics of local recurrent tumors were compared to the primary tumor. Results The imaging series included 73 patients (median age at diagnosis 4.6 years; 56 PF-EPN). Recurrences were observed at up to five time points, with a total of 145 recurrence events documented. At first recurrence most PF-EPN recurred locally (29/56), while ST-EPN relapsed by intracranial dissemination (9/17). Local recurrent tumor grew fast and differed in up to one-fifth from the primary (13.2% lower T2-signal, 14.6% brighter T1-signal, 19% less contrast-enhancement). Leptomeningeal dissemination in ST-EPN is mainly restricted to intracranial (90.5%) while PF-EPN more frequently present with spinal spread (45.7%). Transient post-radiogenic lesions ( n = 2) and secondary malignancies ( n = 2) were rare. Extraneural metastases ( n = 3) were found mainly near the surgical access. Conclusion Recurrences can occur multiple times in EPN patients, and the recurrence patterns differ between ST-EPN and PF-EPN. Imaging characteristics of local recurrences can differ from the primary tumor which is crucial for accurate diagnosis and treatment planning.

Purpose To provide a treatment-focused review and develop basic treatment guidelines for patients diagnosed with pineal anlage tumor (PAT). Methods Prospectively collected data of three patients with pineal anlage tumor from Germany was combined with clinical details and treatment information from 17 published cases. Results Overall, 20 cases of PAT were identified (3 not previously reported German cases, 17 cases from published reports). Age at diagnosis ranged from 0.3 to 35.0 (median: 3.2 ± 7.8) years. All but three cases were diagnosed before the age of three years. For three cases, metastatic disease at initial staging was described. All patients underwent tumor surgery (gross-total resection: 9, subtotal resection/biopsy: 9, extent of resection unknown: 2). 15/20 patients were alive at last follow-up. Median follow-up for 10/15 surviving patients with available follow-up and treatment data was 2.4 years (0.3–6.5). Relapse was reported for 3 patients within 0.8 years after diagnosis. Five patients died, 3 after relapse and 2 from early postoperative complications. Two-year-progression-free- and -overall survival were 65.2 ± 12.7% and 49.2 ± 18.2%, respectively. All 4 patients who received intensive chemotherapy including high-dose chemotherapy combined with radiotherapy (2 focal, 2 craniospinal [CSI]) had no recurrence. Focal radiotherapy- and CSI-free survival rates in 13 evaluable patients were 46.2% (6/13) and 61.5% (8/13), respectively. Conclusion PAT is an aggressive disease mostly affecting young children. Therefore, adjuvant therapy using intensive chemotherapy and considering radiotherapy appears to comprise an appropriate treatment strategy. Reporting further cases is crucial to evaluate distinct treatment strategies.

BACKGROUND:This study aims at clarifying the impact of persistent residual lesions following first-line treatment for pediatric medulloblastoma. METHODS:Data on 84 pediatric patients with medulloblastoma and persistent residual lesions on centrally reviewed magnetic resonance imaging (MRI) at the end of first-line therapy were analyzed. RESULTS:Twenty patients (23.8%) had residual lesions in the tumor bed (R+/M0), 51 (60.7%) had distant lesions (R0/M+) and 13 (15.5%) had both (R+/M+). Overall response to first-line therapy was minor or partial (≥ 25% reduction, minor response [MR]/PR) for 64 (76.2%) and stable disease (SD) for 20 patients (23.8%). Five-year post-primary-treatment progression-free (pptPFS) and overall survival (pptOS) were superior after MR/PR (pptPFS: 62.5 ± 7.0%[MR/PR] vs. 35.9 ± 12.8%[SD], P = .03; pptOS: 79.7 ± 5.9[MR/PR] vs. 55.5 ± 13.9[SD], P = .04). Furthermore, R+/M + was associated with a higher risk for progression (5-year pptPFS: 22.9 ± 17.9%[R+, M+] vs. 72.4 ± 12.0%[R+, M0]; P = .03). Watch-and-wait was pursued in 58 patients, while n = 26 received additional treatments (chemotherapy only, n = 19; surgery only, n = 2; combined, n = 3; valproic acid, n = 2), and their outcomes were not superior to watch-and-wait (5-year pptPFS: 58.5 ± 7.7% vs. 51.6 ± 10.7% P = .71; 5-year pptOS: 76.3 ± 6.9% vs. 69.8 ± 9.7%, P = .74). For the whole cohort, 5-year pptPFS by molecular subgroup (58 cases) were WNT: 100%, SHH: 50.0 ± 35.4%, group-4, 52.5 ± 10.5, group-3 54.2 ± 13.8%; (P = .08). CONCLUSIONS:Overall response and extent of lesions can function as surrogate parameters to predict outcomes in pediatric MB patients with persistent lesions after first-line therapy. Especially in the case of solitary persistent medulloblastoma MRI lesions, additional therapy was not beneficial. Therefore, treatment response, extent/kind of residual lesions and further diagnostic information need consideration for indication of additional treatments for persisting lesions.

ZusammenfassungIn den letzten Jahren wurden biologische Subgruppen des Ependymoms (EPN) identifiziert und in die aktuelle WHO-Klassifikation eingeführt, allerdings haben diese derzeit noch keinen Einfluss auf die Therapiestratifizierung. Jedoch finden sich immer mehr Hinweise, dass das klinische Verhalten abhängig von der Tumorbiologie ist: PF-EPN-A mit einem Zugewinn des Chromosom 1q beispielsweise sind mit einem hohen Risiko für Rezidive assoziiert, während das Überleben bei ST-EPN-YAP1 bei>90% liegt. Die insgesamt noch nicht zufriedenstellende Prognose zeigt, dass die Therapiestrategien weiter verbessert werden müssen. Das Ausmaß der Tumorresektion ist der wichtigste klinische Prognosefaktor, weshalb die Evaluation einer erneuten OP bei einem postoperativen Resttumor höchste Priorität hat. Darüber hinaus wird die Wirksamkeit der Lokalbestrahlung als bewiesen angesehen und derzeit im Alter>1 Jahr empfohlen. Der Stellenwert der Chemotherapie ist weiterhin unklar. Ein Ziel der europäischen klinischen Studie SIOP Ependymoma II ist, die Wirksamkeit verschiedener Chemotherapien zu evaluieren, so dass deutsche Patienten im Rahmen dieser Studie behandelt werden sollten, um den Kenntnisstand voranzutreiben. Neue prognostische biologische Parameter werden im Rahmen des Begleitprojekts BIOMECA validiert. Die Erkenntnisse dieser Begleitstudie sollen auch genutzt werden, um zielgerichtete Therapien sog. Targeted Therapies zu entwickeln. Für Patienten, die nicht im Rahmen der interventionellen Strata der Studie behandelt werden können, stellt die HIT-MED Guidance (aktuelle Version 5.2) eine Handlungsempfehlung dar. Der vorliegende Artikel gibt einen Überblick über Empfehlungen zu Diagnostik und Therapie für Kinder- und Jugendliche mit intrakraniellem Ependymom, sowie zur Behandlung im Rahmen der SIOP Ependymoma II Studie.

Abstract The aim of the HIT-HGG-2007 trial (ISRCTN19852453) was to demonstrate therapeutic non-inferiority of temozolomide radiochemotherapy for pediatric patients (3-18 years) with high-grade gliomas (pedHGG) in comparison to the cisplatinum-based radiochemotherapy of the two previous clinical trials HIT-GBM-C/-D. Between 06/2009 and 12/2016, 456 patients were enrolled at 79 centers in Germany, Austria, and Switzerland (n=18 dropouts, remaining patients for confirmatory analysis: n=438). 438 patients from HIT-GBM-C/-D served as historical control. All pedHGG diagnoses had been confirmed by central neuroradiological and neuropathological review. Primary objective was achieved since non-inferiority of HIT-HGG-2007 in comparison to HIT-GBM-C/-D as indicated by 6 months event-free survival (EFS) was statistically confirmed (p=0.0125). Statistical survival analyses even revealed a better overall survival (OS) and EFS for HIT-HGG-2007 patients in comparison to their HIT-GBM-C/-D counterparts (EFS: p<0.0001; OS: p=0.0328). While EFS subgroup analyses for pontine and non-pontine pedHGG also showed a better survival of HIT-HGG-2007 patients (median EFS pontine pedHGG: 8.2 (n=152; confidence interval (CI): 7.6-9.4) versus 6.2 (n=170; CI: 5.5-6.9) months, p=0.0079; median EFS non-pontine pedHGG: 10.7 (n=276; CI: 9.6-12.4) versus 7.4 (n=267; CI: 6.4-9.2) months, p<0.0001), OS was only improved in HIT-HGG-2007 patients with non-pontine pedHGG (median OS non-pontine pedHGG: 19.3 (CI: 16.8-23.3) versus 16.2 (CI: 14.2-19.1) months; p=0.0181) but not with pontine pedHGG (median OS pontine pedHGG: 11.4 months versus 11.3 months, p=0.4021) Toxicity profile of HIT-HGG-2007 seemed very favorable with most CTCAE (common toxicity criteria adverse event) ≥ grade 3 as hematological toxicity, hepatotoxicity, and neurotoxicity. Less toxicity was observed during concomitant radiochemotherapy in comparison to HIT-GBM-C/-D. Further subgroup survival analyses as well as the assessment of the impact of MGMT promoter methylation are ongoing. In conclusion, our data show non-inferiority of the HIT-HGG-2007 trial with increased survival and less toxicity when compared with previous trials HIT-GBM-C/-D.

Relapsed medulloblastoma (rMB) accounts for a considerable, and disproportionate amount of childhood cancer deaths. Recent advances have gone someway to characterising disease biology at relapse including second malignancies that often cannot be distinguished from relapse on imaging alone. Furthermore, there are now multiple international early-phase trials exploring drug–target matches across a range of high-risk/relapsed paediatric tumours. Despite these advances, treatment at relapse in pre-irradiated patients is typically non-curative and focuses on providing life-prolonging and symptom-modifying care that is tailored to the needs and wishes of the individual and their family. Here, we describe the current understanding of prognostic factors at disease relapse such as principal molecular group, adverse molecular biology, and timing of relapse. We provide an overview of the clinical diagnostic process including signs and symptoms, staging investigations, and molecular pathology, followed by a summary of treatment modalities and considerations. Finally, we summarise future directions to progress understanding of treatment resistance and the biological mechanisms underpinning early therapy-refractory and relapsed disease. These initiatives include development of comprehensive and collaborative molecular profiling approaches at relapse, liquid biopsies such as cerebrospinal fluid (CSF) as a biomarker of minimal residual disease (MRD), modelling strategies, and the use of primary tumour material for real-time drug screening approaches.

To evaluate the clinical impact of isolated spread of medulloblastoma cells into cerebrospinal fluid without additional macroscopic metastases (M1-only). The HIT-MED database was searched for pediatric patients with M1-only medulloblastoma diagnosed from 2000 to 2019. Corresponding clinical and molecular data was evaluated. Treatment was stratified by age and changed over time for older patients. 70 patients with centrally reviewed M1-only disease were identified. Clinical data was available for all and molecular data for 45/70 cases. 91% were non-WNT/non-SHH medulloblastoma (Grp3/4). 5-year PFS for 52 patients ≥ 4 years was 59.4 (± 7.1) %, receiving either upfront craniospinal irradiation (CSI) or SKK-sandwich chemotherapy (CT). Outcomes did not differ between these strategies (5-year PFS: CSI 61.7 ± 9.9%, SKK-CT 56.7 ± 6.1%). For patients < 4 years (n = 18), 5-year PFS was 50.0 (± 13.2) %. M1-persistence occurred exclusively using postoperative CT and was a strong negative predictive factor (pPFS/OS < 0.01). Patients with additional clinical or molecular high-risk (HR) characteristics had worse outcomes (5-year PFS 42.7 ± 10.6% vs. 64.0 ± 7.0%, p = 0.03). In n = 22 patients ≥ 4 years with full molecular information and without additional HR characteristics, risk classification by molecular subtyping had an effect on 5-year PFS (HR 16.7 ± 15.2%, SR 77.8 ± 13.9%; p = 0.01). Our results confirm that M1-only is a high-risk condition, and further underline the importance of CSF staging. Specific risk stratification of affected patients needs attention in future discussions for trials and treatment recommendations. Future patients without contraindications may benefit from upfront CSI by sparing risks related to higher cumulative CT applied in sandwich regimen.

Gorlin syndrome is a genetic condition associated with the occurrence of SHH activated medulloblastoma, basal cell carcinoma, macrocephaly and other congenital anomalies. It is caused by heterozygous pathogenic variants in PTCH1 or SUFU. In this study we included 16 patients from the HIT2000, HIT2000interim, I-HIT-MED, observation registry and older registries such as HIT-SKK87, HIT-SKK92 (1987 – 2020) with genetically confirmed Gorlin syndrome, harboring 10 PTCH1 and 6 SUFU mutations. Nine patients presented with desmoplastic medulloblastomas (DMB), 6 with medulloblastomas with extensive nodularity (MBEN) and one patient with classic medulloblastoma (CMB); all tumors affected the cerebellum, vermis or the fourth ventricle. SHH activation was present in all investigated tumors (14/16); DNA methylation analysis (when available) classified 3 tumors as iSHH-I and 4 tumors as iSHH-II. Age at diagnosis ranged from 0.65 to 3.41 years. All but one patient received chemotherapy according to the HIT-SKK protocol. Ten patients were in complete remission after completion of primary therapy; four subsequently presented with PD. No patient received radiotherapy during initial treatment. Five patients acquired additional neoplasms, namely basal cell carcinomas, odontogenic tumors, ovarian fibromas and meningioma. Developmental delay was documented in 5/16 patients. Overall survival (OS) and progression-free survival (PFS) between patients with PTCH1 or SUFU mutations did not differ statistically (10y-OS 90% vs. 100%, p=0.414; 5y-PFS 88.9% ± 10.5% vs. 41.7% ± 22.2%, p=0.139). Comparing the Gorlin patients to all young, SHH activated MBs in the registries (10y-OS 93.3% ± 6.4% vs. 92.5% ± 3.3%, p=0.738; 10y-PFS 64.9%+-16.7% vs. 83.8%+-4.5%, p=0.228) as well as comparing Gorlin M0 SKK-treated patients to all young, SHH activated, M0, SKK-treated MBs in the HIT-MED database did not reveal significantly different clinical outcomes (10y-OS 88.9% ± 10.5% vs. 88% ± 4%, p=0.812; 5y-PFS 87.5% ± 11.7% vs. 77.7% ± 5.1%, p=0.746). Gorlin syndrome should be considered in young children with SHH activated medulloblastoma, especially DMB and MBEN but cannot be ruled out for CMB. Survival did not differ to patients with SHH-activated medulloblastoma with unknown germline status or between PTCH1 and SUFU mutated patients. Additional neoplasms, especially basal cell carcinomas, need to be expected and screened for. Genetic counselling should be provided for families with young medulloblastoma patients with SHH activation.

PURPOSE The HIT-2000-BIS4 trial aimed to avoid highly detrimental craniospinal irradiation (CSI) in children < 4 years of age with nonmetastatic medulloblastoma by systemic chemotherapy, intraventricular methotrexate, and risk-adapted local radiotherapy. PATIENTS AND METHODS From 2001-2011, 87 patients received systemic chemotherapy and intraventricular methotrexate. Until 2006, CSI was reserved for nonresponse or progression. After 2006, local radiotherapy was introduced for nonresponders or patients with classic medulloblastoma (CMB) or large-cell/anaplastic medulloblastoma (LCA). DNA methylation profiles of infantile sonic hedgehog-activated medulloblastoma (SHH-INF) were subdivided into iSHH-I and iSHH-II subtypes in the HIT-2000-BIS4 cohort and a validation cohort (n = 71) from the HIT group and Russia. RESULTS Five years after diagnosis, patients with desmoplastic medulloblastoma (DMB) or medulloblastoma with extensive nodularity (MBEN; n = 42) had 93% progression-free survival (5y-PFS), 100% overall survival (5y-OS), and 93% CSI-free (5y-CSI-free) survival. Patients with CMB/LCA (n = 45) had 37% 5y-PFS, 62% 5y-OS, and 39% 5y-CSI-free survival. Local radiotherapy did not improve survival in patients with CMB/LCA. All DMB/MBEN assessed by DNA methylation profiling belonged to the SHH-INF subgroup. Group 3 patients (5y-PFS, 36%; n = 14) relapsed more frequently than the SHH-INF group (5y-PFS, 93%; n = 28) or group 4 patients (5y-PFS, 83%; n = 6; P < .001). SHH-INF split into iSHH-I and iSHH-II subtypes in HIT-2000-BIS4 and the validation cohort, without prognostic impact (5y-PFS: iSHH-I, 73%, v iSHH-II, 83%; P = .25; n = 99). Intelligence quotient (IQ) was significantly lower in patients after CSI (mean IQ, 90 [no radiotherapy], v 74 [CSI]; P = .012). CONCLUSION Systemic chemotherapy and intraventricular methotrexate led to favorable survival in both iSHH subtypes of SHH-activated DMB/MBEN with acceptable neurotoxicity. Survival in patients with non-wingless (WNT)/non-SHH disease with CMB/LCA was not improved by local radiotherapy. Patients with group 4 disease had more favorable survival rates than those with group 3 medulloblastoma.

Abstract BACKGROUND Cerebrospinal fluid (CSF) dissemination of medulloblastoma (M1 stage) is a high-risk prognostic factor. However, because diagnostic criteria for M1 staging are missing we specified process-related and cytomorphological parameters influencing the predictive value of the CSF status. PATIENTS AND METHODS CSF samples and cytology reports from 405 medulloblastoma patients of the prospective multicenter trial HIT-2000 were reviewed and related to 5-year progression free survival (5y-PFS). RESULTS Tumor cells were detected in 237/1073 CSF cytospins. M1-patients and M2/3 patients with radiologically detected metastases showed a worse 5y-PFS than M0 patients (54% and 52% vs. 76%; p=0.01 and p<0.001). Lumbar sampling was more sensitive than ventricular sampling. M0 diagnosed specimens containing >50% lytic cells and/or less than 10 nucleated cells showed a decreased 5y-PFS (61%). Further investigation of cytological parameters revealed a poor outcome for cases harboring > 3 tumor cell clusters and individual tumor cells (5y-PFS 33%) vs. cases with ≥ 2 individual tumor cells but no clusters (5y-PFS 61%). In bi-variable Cox-regression, ≥ 2 vs. 0 or 1 tumor cells were associated with a Hazard Ratio (HR) of 0.52 (95%-Confidence Interval (CI): 0.12, 2.30; p=0.39), whereas > 3 vs. no tumor cell clusters were associated with a HR of 8.94 (95%-CI: 1.66, 48.22; p=0.01). CONCLUSIONS CSF staging in medulloblastoma should comprise lumbar specimens with <50% lytic cells and a minimum of 10 nucleated cells. The predictive value of CSF cytology in M1 cases may predominantly depend on tumor cell clusters. The latter finding needs to be confirmed in prospective trials.

Abstract OBJECTIVE To avoid craniospinal irradiation (CSI) in children younger than four years with non-metastatic medulloblastoma by chemotherapy, intraventricular methotrexate and risk-adapted local radiotherapy. PATIENTS AND METHODS Eighty-seven patients received systemic chemotherapy and intraventricular methotrexate. Until 2006, CSI was reserved for non-response or progression. After 2006, local radiotherapy was introduced for non-responders or classic (CMB), anaplastic or large-cell medulloblastoma (LCA). Infantile SHH-activated medulloblastomas (SHH_INF) were subdivided by DNA-methylation profiling. Survival in SHH_INF subtypes were also assessed in a validation cohort (n=71). RESULTS Patients with desmoplastic medulloblastoma (DMB) or medulloblastoma with extensive nodularity (MBEN) (n=42) had 93% 5-year PFS, 100% 5-year OS and 93% 5-year CSI-free survival. Patients with CMB/LCA (n=45) had 37% 5y-PFS, 62% 5y-OS and 39% 5y-CSI-free survival. Local radiotherapy did not improve survival in CMB/LCA patients. All DMB/MBEN assessed by DNA methylation profiling belonged to the SHH_INF subgroup. Group 3 patients (5y-PFS 36% [n=14]) relapsed more frequently than SHH_INF (5y-PFS 93% [n=28]) or Group 4 patients (5y-PFS 83% [n=6], p<0.001). SHH_INF split into iSHH-I and iSHH-II subtypes in HIT-2000-BIS4 and the validation cohort, without prognostic impact (5y-PFS: iSHH-I 73% vs. iSHH-II 83%, p=0.25, n=99). Mean IQ was 90 (radiotherapy-free survivors) vs. 74 (patients that received CSI) [p=0.012]. CONCLUSION Systemic chemotherapy and intraventricular methotrexate led to favorable survival in both iSHH-subtypes of SHH-activated DMB/MBEN with acceptable neurotoxicity. Survival in non-WNT/non-SHH CMB/LCA patients was not improved by local radiotherapy. Survival was more favorable in patients with Group 4 than in patients with Group 3 medulloblastoma.

Background. With rising numbers of childhood cancer survivors, somatic and socioeconomic outcome as well as health-related quality of life (QoL) gain increasing relevance. Based on the first nationwide German Survey on Life Situation, State of Health, and Quality of Life of Childhood Cancer Survivors, the VIVE survey, we report the outcome of survivors of childhood brain tumors localized in the posterior fossa. Methods. Two hundred seventy participants with a median follow-up period of 21.9 years completed a questionnaire on socioeconomic and somatic late effects as well as a standardized QoL questionnaire (European Organisation for Research andTreatment of Cancer QLQ-C30). Comparisons were performed between World Health Organization (WHO) grades I-II, WHO grades III-IV brain tumor survivors (BTS), and the general population adjusting for potential confounders. Results. The socioeconomic and QoL results of WHO grades I-II BTS were largely comparable to the general population, while grades III-IV BTS were at higher risk for significantly worse outcomes. Of WHO grades III-IV BTS, 36.8% were still living with their parents or in assisted living facilities compared with 16.1% of grades I-II BTS and 7.8% of the age-adjusted general population. Of grades III-IV BTS, 60.8% achieved at least an intermediate school degree in comparison to 80.5% of grades I-II BTS and 75.6% of the general population. Grades III-IV BTS developed up to 2 times more somatic late effects than survivors of grades I-II tumors. Conclusion. Derived from a large and homogeneous cohort, these results stress the importance of an appropriate follow-up period focusing not only on physical aspects but encompassing the entire living situation to allow patient-tailored support. Importance of the Study Other studies concerning socioeconomic and somatic late effects after treatment for childhood cancer have shown that BTS tend to a poor outcome relating to educational and social attainment in comparison to other childhood cancer survivors. This study not only assesses socioeconomic and somatic late effects in a German BTS cohort but also links these results to health-related QoL, thus allowing a more holistic evaluation of the quality of survival. This might help to provide better patient-tailored care and psychosocial support in individual patients and will contribute to more risk-stratified follow-up concepts.