Implantation of biodegradable wafers near the brain surgery site to deliver anti-cancer agents which target residual tumor cells by bypassing the blood-brain barrier has been a promising method for brain tumor treatment. However, further improvement in the prognosis is still necessary. We herein present novel materials and device technologies for drug delivery to brain tumors, i.e., a flexible, sticky, and biodegradable drug-loaded patch integrated with wireless electronics for controlled intracranial drug delivery through mild-thermic actuation. The flexible and bifacially-designed sticky/hydrophobic device allows conformal adhesion on the brain surgery site and provides spatially-controlled and temporarily-extended drug delivery to brain tumors while minimizing unintended drug leakage to the cerebrospinal fluid. Biodegradation of the entire device minimizes potential neurological side-effects. Application of the device to the mouse model confirms tumor volume suppression and improved survival rate. Demonstration in a large animal model (canine model) exhibited its potential for human application.

Objectives: To evaluate patient outcome and investigate the prognostic factors of high-grade meningiomas by adopting the 2000 World Health Organization (WHO) classification system. Methods: Between 1986 and 2004, 74 patients were diagnosed with high-grade meningioma: 33 with atypical and 41 with anaplastic meningioma. The mean follow-up was 58.5 months. We reclassified all surgical specimens, according to the 2000 WHO classification system, using two expert neuropathologists. Results: Forty of 74 meningiomas were reclassified as atypical meningioma and 24 as anaplastic meningioma. Overall and recurrence-free survivals were significantly longer in patients with atypical than in those with anaplastic meningioma: 142.5 versus 39.8 months and 138.5 versus 32.2 months, respectively (p<0.001). In patients with atypical meningiomas, brain invasion and adjuvant radiotherapy were not associated with survival; however, in the brain invasion subgroup, adjuvant radiotherapy improved patients’ survival. In patients with anaplastic meningioma, the prognostic factors were brain invasion, adjuvant radiotherapy, malignant progression, p53 overexpression and extent of resection. The p53 overexpression was the only factor associated with malignant progression (p = 0.009). Conclusions: The 2000 WHO classification has identified the truly aggressive meningiomas better than did the previous criteria. A precise meningioma grading system may help to avoid over-treatment of patients with an atypical meningioma as, once the tumour has “declared itself” by recurrence and histological features, it becomes a tumour that is poorly amenable to current therapies.

BACKGROUND: To evaluate the hearing preservation rate and to determine its prognostic factors after gamma knife (GK) stereotactic radiosurgery (SRS) in patients with vestibular schwannoma, the authors used a prospective study design to analyze these patients.METHODS: Between December 1997 and January 2002, 25 patients with vestibular schwannoma with serviceable hearing were enrolled in the current study. The median tumor volume was 3.0 cc (0.16–9.1 cc). The prescription dose was 12.0 ± 0.7 gray at an isodose line of 49.8 ± 1.1%. The tumor control rate and complications were evaluated by focusing on hearing preservation and its prognostic factors.RESULTS: Based on radiologic study, the tumor control rate was 92% during the median follow‐up period of 45 months. The trigeminal and facial nerve preservation rates were 95% and 100%, respectively. Thirteen (52%) of the 25 patients preserved serviceable hearing and 9 (36%) patients retained their pre‐GK G‐R grade levels after GK SRS. However, 16 patients showed hearing deterioration > 20 dB within 3–6 months and this trend continued for 24 months after the treatment. The maximum radiotherapy dose delivered to the cochlear nucleus was the single, significant prognostic factor of hearing deterioration.CONCLUSIONS: The authors concluded that a more sophisticated strategy to prevent hearing deterioration during the first 6 months post‐GK SRS is necessary to improve long‐term hearing preservation. Cancer 2005. © 2005 American Cancer Society.