Neurological Surgery最新文献

Due to the sharp decline in the birth rate in Japan, a severe decline in pediatric brain tumor cases is expected. Ependymoma accounts for 5.4% of pediatric brain tumors, and due to its poor prognosis, understanding treatment outcomes is crucial. However, in Japan, it is difficult to accurately understand treatment outcomes. Meanwhile, the World Health Organization's diagnostics have increasingly emphasized molecular diagnosis, making the establishment of a diagnostic system crucial. Although treatment guidelines have been published, due to trends in overseas clinical research, clinical practice does not necessarily conform to the 2022 guidelines. Amid changes in the medical system resulting from the rapid decline in the birthrate, this paper outlines the current status and outlook for clinical trials, both globally and in Japan.

Pediatric brain tumors are the leading cause of cancer-related deaths in children, and cause unique suffering by degrading the neurological functions essential to a child's identity. Palliative care is no longer seen as terminal care, but rather as a crucial approach to improve quality of life (QOL), which should integrated from the time of diagnosis alongside curative therapy. Effective symptom management is fundamental, addressing increased intracranial pressure with steroids, and pain via a stepwise approach using opioids, adjuvant analgesics, seizures, and swallowing difficulties through multidisciplinary collaboration. Palliative intent surgery, such as a cerebrospinal fluid shunt or tumor debulking, and palliative radiotherapy can provide significant symptom relief. There is also a growing desire for home-based care, which requires a seamless transition supported by a close collaboration between hospitals and community medical teams. This was achieved through pre-discharge conferences to share prognoses, specific emergency care plans, and 24-hour support. The principles of shared decision-making (SDM) and Advance Care Planning (ACP) are vital to ensure that care aligns with the patient and family values through ongoing dialogue. The neurosurgeon's role extends beyond technical procedures to coordinate comprehensive care and empower patients and their families throughout the course of illness.

Medulloblastoma is the most common malignant brain tumor in children. Advances in sequencing technologies have allowed the identification of four major molecular subgroups, each defined by distinct genetic alterations, biological features, and clinical courses. Recent studies have shown that medulloblastomas arise following disruptions in normal neurodevelopment, in which genetic abnormalities impair differentiation and lead to the persistence and malignant transformation of normally eliminated progenitor cells. Subgroup-specific cell of origin have since been identified. In Group 3 and Group 4, which were previously poorly understood, genetic alterations were shown to impair neuronal differentiation, revealing their pathogenesis. In SHH medulloblastomas, mutations in genes associated with RNA biology, including ELP1 and U1 snRNA, highlight alternative mechanisms of tumor development. Each subgroup can be further divided into subtypes that enable finer distinctions between clinical outcomes, support treatment intensification in high-risk patients, and de-escalation strategies in favorable groups. Although medulloblastoma is one of the best-studied pediatric brain tumors, its complexity continues to present challenges, and a deeper understanding of its molecular heterogeneity is essential to advance risk-adapted and targeted therapies.

Endoscopy provides a bright, wide field of view in deep surgical corridors, and preserves image quality under continuous irrigation ("underwater" conditions). Pediatric patients tolerate limited blood loss and are vulnerable to retraction injuries; therefore, meticulous hemostasis and brain-sparing techniques are mandatory. As hydrocephalus commonly accompanies pediatric brain tumors, treatment should address both tumor control and cerebrospinal fluid diversion within the same operation. Endoscopy enables access through minimal corridors, and is particularly effective for deep-seated lesions. Safe application requires rigorous preoperative planning and simulation to delineate the lesion, feeding and draining vessels, critical white matter tracts, and deep venous structures near the intended corridor. Patient positioning and operating room setup must be optimized in advance. When underwater techniques are anticipated, the angle of the tubular retractor (cannula/cylinder) should allow the maintenance of a stable fluid column. This article provides a practice-oriented overview of the endoscopic management of pediatric intraventricular and intraparenchymal tumors, emphasizing the importance of planning, workflow discipline, and strategies that minimize blood loss and parenchymal injury, while integrating diagnosis, cytoreduction, and CSF pathway reconstruction.

With the improvement in survival rates, the goal of pediatric oncology is to shift from improving survival rates to living with cancer and surviving in good health without serious late complications. The same is true for pediatric brain tumors. Depending on the individual patient's risk of late complications, long-term follow-up should be conducted with appropriate frequency, intensity, and structure to detect possible intervening factors and implement early intervention, with attention to possible endocrine complications, cognitive dysfunction, organ damage, vascular disease, and secondary tumors in the late stages. Addressing psychosocial issues specific to adolescents and young adults, as well as providing transition support and assistance with learning, employment, and independence difficulties associated with higher brain dysfunction, is also important. As neurosurgeons have limitations in dealing with these problems, it is necessary to establish a continuous and organic medical and support system for the patient's lifetime in collaboration with pediatrics, internal medicine, departments specializing in complication care, nurses, pharmacists, psychologists, rehabilitation centers, social workers, community medicine, and social welfare support. To this end, there appears to be an urgent need to train personnel involved in the long-term follow-up of pediatric brain tumors.

The molecular classification of pediatric brain tumors enables radiotherapy optimization. Proton-beam therapy and reirradiation offer clinical benefits. However, large-scale studies of these issues are ongoing. Once the results are available, careful interpretation of new findings and consensus among expert oncologists will be essential to ensure the safe application of radiotherapy.

Over the past decade, molecular biology techniques have identified numerous key genetic mutations in brain tumors. This has improved understanding of disease pathogenesis, and facilitated prognostic prediction, and the development of effective targeted molecular therapies. In 2021, the World Health Organization published the fifth edition of its classification of CNS tumors(WHO 5^th), recommending a reporting format based on an integrated diagnosis combining histopathological and molecular genetic information. The classification of pediatric brain tumors has also advanced significantly, clarifying the disease backgrounds specific to childhood and differences in prevalence. The WHO 5^th classification represents a significant advancement in selecting optimal treatments and recognizing patient groups that share similar clinical characteristics. However, some challenges remain for its implementation in routine clinical practice, including establishing access to molecular genetic testing. Herein, we reviewed the tumor types listed in the WHO 5^th edition that predominantly affect children and adolescents, referring to recently published reports and concepts.

Pediatric brain tumors result in diverse neurological and functional impairments arising from both the tumor itself and its treatment, including surgery, radiotherapy, and chemotherapy. Advances in oncological therapies have improved long-term survival rates, creating an increasing need for comprehensive rehabilitation throughout the acute, recovery, and community phases. Rehabilitation must address motor, cognitive, swallowing, communication, and psychosocial challenges through a multidisciplinary and developmentally informed approach. The International Classification of Functioning, Disability, and Health framework provides a useful structure for integrating interventions targeting body functions, activities, and participation. Early intervention, developmental alignment, and environmental modification are essential to optimize outcomes and promote participation in daily life and education. Long-term follow-up is required, as late effects and higher-order cognitive dysfunction often emerge during growth and school-age years. Effective coordination among medical, educational, and social services is critical to ensure continuity of care, including transition and vocational support during adolescence and adulthood. Despite growing recognition of its importance, evidence-based rehabilitation protocols and interinstitutional collaboration remain limited. Further research is needed to standardize assessment and intervention practices, develop longitudinal care models, and establish networks linking oncology, rehabilitation, and community resources to support each child in achieving a meaningful and self-directed life.

Precision medicine in pediatric brain tumors aims to transcend traditional organ-based therapy by customizing treatment according to each patient's tumor molecular and genomic profiles. By leveraging comprehensive genomic profiling and expert panel reviews, actionable mutations may direct the use of targeted therapies or immunotherapies. In July 2025, three oncology societies in Japan released a joint briefing report outlining 12 reform proposals to optimize the cancer gene panel testing system. Included among these are timing restrictions on testing, loosening the expert panel criteria. These reforms are designed to enhance test utility, improve patient access, and ultimately improve survival outcomes of pediatric patients with brain tumors.

After leukemia, pediatric brain tumors are the second most common childhood malignancies and are associated with significant neurologic and developmental sequelae, rendering accurate and early diagnosis critical. The 2021 World Health Organization classification for central nervous system tumors emphasizes the utility of molecular pathology in distinguishing between pediatric and adult brain tumors. Imaging studies, including magnetic resonance imaging (T1-, T2-, diffusion-, and perfusion-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy) and positron emission tomography using fluorodeoxyglucose or amino acid tracers, integrate structural assessment with functional and quantitative techniques, enabling the evaluation of cellularity, perfusion, and metabolism. Characteristic imaging patterns support diagnosis and prognosis across tumor types, including diffuse gliomas (adult- and pediatric-type, low- and high-grade subtypes), circumscribed astrocytic gliomas, ependymomas, glioneuronal tumors, choroid plexus tumors, embryonal tumors (e.g., medulloblastoma), pineal region tumors, craniopharyngiomas, nerve sheath tumors, germ cell tumors, meningiomas, Langerhans cell histiocytosis, hamartomas, and cavernous malformations. Molecular features increasingly guide treatment strategies. Emerging technologies, such as radiomics and artificial intelligence (AI), are improving tumor classification, segmentation, and recurrence prediction, with advances such as federated learning and explainable AI supporting privacy-preserving and interpretable models. Imaging also plays roles beyond detection, including surgical planning, treatment monitoring, and prognostication. Future integration of multimodal imaging and AI is expected to improve precision, standardization, and individualized pediatric neuro-oncology care through rapid, noninvasive diagnostics.