The efficacy of immune checkpoint inhibitors against brain metastases from non-small cell lung cancer remains suboptimal, potentially owing to differences in the tumor immune microenvironment between primary tumors and brain metastases. We characterized the tumor immune microenvironment of 26 paired samples to evaluate the impact of metastatic timing (synchronous brain metastasis vs. metachronous brain metastasis). Immunohistochemistry was performed for CD163, CD3, CD8, programmed cell death 1, FoxP3, programmed cell death ligand 1, and peripheral lymph node addressin. Paired analysis of primary tumors and brain metastases within each group revealed distinct immunological shifts. In the metachronous brain metastasis group, brain metastases exhibited significantly decreased CD3+ density compared with their matched primary tumors and larger CD163+ areas, yielding a relatively higher FoxP3/CD3. Conversely, in the synchronous brain metastasis group, the CD8/CD3 was significantly higher in brain metastases, whereas CD3+ density showed a decreasing trend. Comparisons of groups revealed that the synchronous brain metastasis group had a significantly higher FoxP3/CD3 in primary tumors and higher programmed cell death ligand 1 expression in brain metastases. Notably, primary tumor FoxP3/CD3 correlated significantly with programmed cell death ligand 1 expression in both primary tumors and brain metastases. Survival analysis revealed that higher CD3+ densities in both sites were associated with prolonged overall survival. In conclusion, metastatic timing serves as a clinical surrogate for distinct biological tumor immune microenvironment profiles. Synchronous metastasis is characterized by an immunosuppressive state involving FoxP3+ cells and programmed cell death ligand 1 expression originating from the primary tumor stage. Furthermore, the relative maintenance of FoxP3+ cells in brain metastases across both groups highlights the unique immunosuppressive nature of the brain. These findings provide a rationale for the basis of future research on patient stratification strategies.
Aneurysmal subarachnoid hemorrhage requires prompt aneurysm securing and coordinated perioperative management to prevent delayed cerebral ischemia and systemic complications. We evaluated whether implementation of a standardized perioperative management protocol incorporating neurointensivist co-management was associated with improved outcomes. This single-center retrospective observational cohort study included consecutive patients treated between January 2012 and July 2023. Patients managed with the standardized protocol from April 2015 to July 2023 were compared with those receiving conventional care from January 2012 to March 2015. The primary outcome was the modified Rankin Scale score at 6 months. Secondary outcomes included favorable functional outcome, mortality, delayed cerebral ischemia, angiographic vasospasm, delayed cerebral ischemia-related cerebral infarctions, permanent neurological complications, composite respiratory outcome, and culture-confirmed hospital-onset infection. Multivariable analyses were adjusted for prespecified covariates. Among 455 patients, 100 were in the control group and 355 in the protocol-based group. The protocol-based group had better 6-month modified Rankin Scale scores (adjusted odds ratio, 0.43; 95% confidence interval, 0.28-0.65), a higher rate of favorable functional outcome, and lower mortality. The protocol-based group also had lower odds of delayed cerebral ischemia (adjusted odds ratio, 0.41; 95% confidence interval, 0.21-0.81) and the composite respiratory outcome (adjusted odds ratio, 0.33; 95% confidence interval, 0.19-0.58). Angiographic vasospasm and culture-confirmed hospital-onset infection did not differ significantly. Standardized perioperative management with neurointensivist co-management was associated with improved 6-month functional outcomes and lower rates of selected complications.
We developed and evaluated a neuroendoscopic training system using a 3-dimensional printed brain model with a water-filled ventricular environment and a side-view visualization structure. A 3-dimensional printed neuroendoscopic training model was fabricated from preoperative computed tomography and magnetic resonance imaging data. A soft polyurethane brain model immersed in water within a transparent container was used to simulate cerebrospinal fluid conditions. Ten neurosurgeons evaluated anatomical reproducibility and neuroendoscopic manipulation skills using a 4-point scale. Evaluated items included identification of intraventricular anatomical structures, use of basic neuroendoscopic manipulation techniques, and avoidance of ventricular wall contact. Anatomical structures within the lateral and third ventricles were generally well reproduced, although several deep structures in the posterior third ventricle received lower ratings. Basic neuroendoscopic manipulation techniques received favorable self-evaluations, whereas ventricular wall contact avoidance scores were lower. Favorable ratings were observed in 92.5% of evaluations for basic neuroendoscopic manipulation techniques compared with 37.5% for ventricular wall contact avoidance, demonstrating a significant difference between the 2 categories (p = 0.002). Educational usefulness of the training system received a median score of 3 (interquartile range, 3-4), with a favorable evaluation rate of 80%. This exploratory study suggests that this training system may be useful not only for acquiring basic neuroendoscopic skills but also for visualizing and learning how to avoid ventricular wall contact during neuroendoscopic procedures.
Lateral suboccipital craniotomy is frequently used for cerebellopontine angle lesions, during which the mastoid air cells may be opened. This study evaluated whether the autologous bone paste technique prevents postoperative cerebrospinal fluid leakage and anatomically reconstructs the mastoid air cells. Eighty-six patients who underwent lateral suboccipital craniotomy with opened mastoid air cells were included in this study. The opened cells were sealed with various methods, including the autologous bone paste technique, in which bone dust harvested during the craniotomy was mixed with fibrinogen solution and stabilized with thrombin solution. We compared the postoperative incidence of cerebrospinal fluid leakage and infectious complications between patients who underwent reconstruction using autologous bone paste and those treated with alternative materials. Furthermore, in cases with over 1 year of postoperative follow-up using computed tomography, we evaluated the degree of mastoid air-cell reconstruction and longitudinal changes in computed tomography values. Histological analyses were also performed on the reconstructed areas from 2 reoperation cases. Postoperative cerebrospinal fluid leakage and infectious complications were comparable between the groups. However, the degree of mastoid air-cell reconstruction was significantly better in the bone paste group than in the non-bone paste group. Histological analyses revealed that the reconstructed sites contained osteoblasts, osteocytes, and osteophytes without an inflammatory response, and osseous lamellae around the Haversian canal were observed. In conclusion, autologous bone paste is a simple osteogenic sealant that effectively seals the opened mastoid air cells in lateral suboccipital craniotomy.
Background: Emergency surgery for brain tumors is regarded as a life-saving intervention, but in contemporary neuro-oncological practice it may also serve diagnostic, stabilizing, and treatment-enabling roles. Methods: We retrospectively reviewed consecutive patients who underwent emergency surgery for brain tumors at a single institution between January 2020 and December 2025. Results: Among 352 brain tumor operations, 59 cases (16.8%) met the study definition of emergency surgery. The frequency of emergency surgery varied by tumor type, being highest in primary central nervous system lymphoma (11/18, 61.1%), followed by brain metastases (25/74, 33.8%), hemangioblastoma (2/7, 28.6%), glioma (15/83, 18.1%), pituitary neuroendocrine tumor (1/15, 6.7%), and meningioma (5/106, 4.7%). Emergency cases were stratified into four operational categories: life-saving surgery, malignant oncological emergency surgery, intentional delayed surgery after stabilization, and semi-urgent surgery. Tumor resection was performed in 42 patients (71.2%) and biopsy was performed in 17 (28.8%); all primary central nervous system lymphoma cases underwent diagnostic biopsy with intraoperative rapid pathology. Regarding operative timing, 34 procedures (57.6%) were completed within the 08:00-17:00 time frame, 17 (28.8%) started within the 08:00-17:00 time frame but extended beyond 17:00, and eight (13.6%) started at or after 17:00. Median preoperative and discharge modified Rankin Scale scores were both 3, with improvement in 21 patients, no change in 29, worsening in 7, and in-hospital death in two. Time to treatment initiation was evaluable in 41 malignant tumor cases requiring subsequent tumor-specific therapy, and differed according to tumor type. Conclusions: Capacity-aware triage may help balance neurological urgency, tumor-specific therapeutic goals, preoperative stabilization, patient safety, and surgical quality under structured work-hour management.
