Prabhu, Vikram C.

BACKGROUND AND OBJECTIVES: Symptomatic hydrocephalus (HCP) requiring cerebrospinal fluid diversion by shunting is routinely performed through ventriculoperitoneal or ventriculoatrial (VA) shunting. The optimal method of distal catheter placement for a VA shunt is not well defined. We detail a novel surgical technique for VA shunt placement using intraoperative digital subtraction angiography (DSA). METHODS: The aim of this single-institution, retrospective review was to describe a unique technique of distal catheter placement in a series of the initial 50 consecutive adult patients who underwent VA shunt placement with DSA at our institution between 2021 and 2024. Detailed procedural techniques and outcomes are described. RESULTS: Accurate surgical placement of the distal VA shunt was achieved in 48 patients (96%). Five patients required shunt revisions for delayed shearing of distal catheter (1), suboptimal distal catheter placement (3), and suboptimal proximal catheter placement (1). Four instances of post-VA shunt bacteremia were found when patients were routinely cultured for febrile episodes; all completed appropriate antibiotic course, and none resulted in meningitis or required shunt revision. Kaplan-Meier analysis demonstrated overall VA shunt success of 92% at 3 years after initial surgery. CONCLUSION: This series of 50 consecutive patients demonstrated use of intraoperative DSA yields safe and accurate placement VA shunts with acceptable long-term outcomes. As more neurosurgeons have endovascular training, this surgical technique may be more readily adopted.

Abstract Recurrence pattern in high grade glioma is classified as local and distant recurrence based on distance from original resection cavity and radiation field. We report the first series of three cases of O6-methylguanine-DNA methyltransferase (MGMT) promoter methylated high grade glioma with distant recurrence without local recurrence throughout the disease course. Patient 1: 65 year-old female with WHO grade 4 glioblastoma, isocitrate dehydrogenase enzyme (IDH) wild type (WT), MGMT methylated. She underwent gross total resection followed by Stupp protocol. Postoperative ischemic volume was < 1 ml. Distant recurrence occurred 4 months after completion of Stupp protocol. Patient 2: 55 year-old male with WHO grade 4 glioblastoma, IDH wild type, MGMT methylated. He underwent gross total resection followed by Stupp protocol. Postoperative ischemic volume was 18 ml. Distant recurrence occurred 5 months after completion of Stupp protocol. Patient 3: 31 year-old male with WHO grade 4 astrocytoma, IDH mutant, MGMT promoter methylated. He underwent gross total resection followed by Stupp protocol. Postoperative ischemic volume was 2 ml. Distant recurrence occurred 10 months after completion of Stupp protocol. Distant recurrence is more common in MGMT promoter methylated tumors. All 3 patients in our case series had poor outcomes after distant recurrence without local recurrence at the original tumor site. This observation indicates good local control in MGMT promoter methylated high grade glioma with current standard treatment. For one patient, next generation sequencing (NGS) was available for both original and recurrent tumor and did not reveal any major differences in the genetics of original tumor and distant recurrent tumor other than temozolomide induced high tumor mutational burden in the distant recurrent tumor. Understanding risk factors for distant recurrence in MGMT promoter methylated high grade gliomas and investigating correlations between recurrences will help plan therapeutic strategies to prevent distant recurrence and improve outcomes.

Abstract Background Advanced age is a major risk factor for the development of many diseases including those affecting the central nervous system. Wild-type isocitrate dehydrogenase glioblastoma (IDHwt GBM) is the most common primary malignant brain cancer and accounts for ≥90% of all adult GBM diagnoses. Patients with IDHwt GBM have a median age of diagnosis at 68–70 years of age, and increasing age is associated with an increasingly worse prognosis for patients with this type of GBM. Methods The Surveillance, Epidemiology, and End Results, The Cancer Genome Atlas, and the Chinese Glioma Genome Atlas databases were analyzed for mortality indices. Meta-analysis of 80 clinical trials was evaluated for log hazard ratio for aging to tumor survivorship. Results Despite significant advances in the understanding of intratumoral genetic alterations, molecular characteristics of tumor microenvironments, and relationships between tumor molecular characteristics and the use of targeted therapeutics, life expectancy for older adults with GBM has yet to improve. Conclusions Based upon the results of our analysis, we propose that age-dependent factors that are yet to be fully elucidated, contribute to IDHwt GBM patient outcomes.