Open Access

Background: Intracranial choroid plexus tumors (CPT) are rare and primarily affect young children. Leptomeningeal dissemination (LMD) has been reported not only in high-grade choroid plexus carcinoma (CPC) but also in lower histological grades; however, a systematic evaluation of CPT-specific imaging characteristics remains lacking. Methods: We analyzed the imaging characteristics of LMD in a single-center pediatric cohort of 22 CPT patients (thirteen choroid plexus papilloma (CPP), six atypical choroid plexus papilloma (aCPP), three CPC), comparing LMD features with those of the primary tumor. Additionally, we examined the correlation between resection status and LMD development during follow-up. Results: At diagnosis, we observed true LMD in three (two CPCs, one CPP) and pseudo-LMD in one case (CPP). During follow-up, two CPP patients developed cystic LMD, and one aCPP patient developed a solid metastasis. LMD had characteristics of the primary tumor in 3/4 cases. Incomplete resection was associated with a higher risk of LMD ( p = 0.025). Conclusions: LMD can occur in both high- and lower-grade CPT, presenting at diagnosis as well as in relapsed lower-grade cases. Notable MR-imaging features include pseudo-LMD at diagnosis and cystic LMD in relapsed CPP cases. Incomplete tumor resection may increase the risk of LMD, although further validation is needed.

Aims Our objective was to analyse tumour- and treatment-related factors influencing endocrine morbidity and obesity pre- and post-proton beam therapy (PBT) in paediatric patients with craniopharyngioma. Materials and methods A total of 65 patients at the onset of PBT were included in the analysis within our prospective registry study. The data pertaining to endocrine deficits and BMI prior to PBT were retrieved from the medical records on a retrospective basis. Cumulative incidences (CI) of endocrinopathies, age- and sex-adjusted BMI standard deviation scores (BMI-SDS) were calculated. Results Before PBT, 90.8% had ≥1 neuroendocrine deficit. Diabetes insipidus (DI) was attributed to surgery in 96%. Patients with postoperative DI had a higher 3-year CI of adrenocorticotropic hormone and thyroid-stimulating hormone deficiency rates compared to those without DI (p < .001). At PBT start, 47.7% had already panhypopituitarism compared to 67.7% at the last follow-up (FU). Median FU post-PBT was 3.2 years (range, 1.0–9.6). Post-PBT, 38.2% remained free of additional hormone deficiencies. A trend towards lower endocrine morbidity scores for patients who received PBT during their primary treatment compared to irradiation at progression did not reach statistical significance (p = .068). The BMI-SDS increase from diagnosis to the start of radiotherapy was significantly greater than from the start of PBT to the end of FU (mean BMI-SDS increase: 0.61, ±1.16 vs. 0.13, ±0.84, p = 0.019), with a median time of 10.2 and 38.4 months, respectively. In the multivariate analysis, hypothalamic involvement (p = .042) and the BMI-SDS level at diagnosis (p = .006) were identified as clinical factors indicating severe obesity at FU (BMI-SDS ≥+2). Conclusions Panhypopituitarism is frequently observed in paediatric patients with craniopharyngioma prior to PBT. The potential benefits of early PBT on endocrine outcomes require further investigation through longer FU periods. The greatest increase in weight occurred before radiotherapy. Endocrine deficiencies and weight gain are multifactorial and require close monitoring.

Paediatric high-grade gliomas (pedHGGs) are highly invasive brain tumours accounting for approximately 15 % of all central nervous system (CNS) tumours in children and adolescents. The outcome for these tumours is generally poor with 5-year survival rates of less than 20 %. Despite improved biological insights into pedHGGs and the promise of more effective therapies, little progress has been made in the effective treatment and the outcome of these tumours over the last four decades. Much of the evidence for the use of chemotherapy in pedHGGs is extrapolated from adult data, and the evidence for its use in the paediatric population is still weak. This guideline was written by members of the SIOPE HGG Working Group as part of the European Standard Clinical Practice (ESCP) Project. The guideline aims to integrate available evidence-based and expert opinion-based information to assist healthcare professionals in the management of pedHGGs and in an attempt to provide equity in healthcare reflecting the varying resources of each European country.

Choroid plexus tumours (CPT) are rare epithelial brain tumours that primarily affect very young children. They can be classified as benign choroid plexus papilloma (CPP, WHO grade 1), intermediate grade atypical choroid plexus papilloma (aCPP, WHO grade 2) or highly malignant choroid plexus carcinoma (CPC, WHO grade 3). Treatment is dependent on tumour grade, surgical resection, the age of the child and somatic and germline TP53 mutational status. CPP and aCPP have a good prognosis and are frequently curable with surgery alone. In contrast, the prognosis in CPC is often poor, despite intensive multimodal treatment with surgery, chemotherapy and radiotherapy. Management is complicated by the increased incidence of germline TP53 mutations and cancer predisposition (Li-Fraumeni syndrome), especially in CPC, whilst the rarity of the diagnosis means there are a lack of robust clinical data on which to base treatment decisions. Studies generally comprise of retrospective, single arm and centre trials or case series, and patient numbers are small leading to conflicting results that are difficult to interpret. Standardised treatment protocols have historically been lacking. The aim of this document is to provide a reference standard for the treatment of CPT on behalf of the European Society for Paediatric Oncology (SIOPE). We review the previously published literature and provide consensus key recommendations for the management of CPP, aCPP and CPC including surgical approaches and when appropriate, the role of chemotherapy and radiotherapy. Suggested follow-up and possible relapse strategies are also suggested.

Background: Malignant rhabdoid tumors occasionally develop along cranial nerves, but clinical, histopathological, and molecular features have not been examined in larger series. Procedure: We retrospectively interrogated data from the European Rhabdoid Registry, EU-RHAB, to identify malignant rhabdoid tumors affecting cranial nerves. We retrieved clinical information and reviewed magnetic resonance imaging (MRI) data. Furthermore, histopathological review and molecular profiling were performed. Results: Among 425 patients, we identified a total of 14 harboring malignant rhabdoid tumors with cranial nerve involvement. Median age at diagnosis was 28 months (range: 0–13 years). Various cranial nerves were affected, the trigeminal nerve (n = 4) and the facial and/or vestibulocochlear nerve (n = 5) being most frequently involved. In most cases, the initial clinical and neuroradiological suspicion was schwannoma. Neuroradiology review of magnetic resonance imaging studies confirmed a tumor

Purpose 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. Methods 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. Results 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%±3.3%, pediatric B: 69.5 ± 8.6%, PFS = 0.02), were associated with inferior PFS, especially in aCPP. Conclusion Incomplete resection and biology impact on PFS especially in aCPP. These results extend the evidence for current stratification and treatment strategies.