Coexisting Biopsy-Diagnosed Dementia and Glioblastoma.

Both glioblastoma (GBM) and dementia are devastating diseases with limited treatments that are usually not curative. Having clinically diagnosed dementia with an associated biopsy-proven etiology and a coexisting GBM diagnosis is a rare occurrence. The relationship between the development of neurodegenerative dementia and GBM is unclear, as there are conflicting reports in the literature. We present two cases of simultaneous biopsy-proven dementia, one with Alzheimer's disease (AD) and GBM, and one with cerebral amyloid angiopathy (CAA) and GBM. We discuss how these diseases may be associated. Whether one pathologic process begins first or develops concurrently is unknown, but certain molecular pathways of dementia and GBM appear directly related while others inversely related. Further investigations of these close molecular relationships between dementia and GBM could lead to development of improved diagnostic tools and therapeutic interventions for both diseases.

Tumor sound, auditory cues, and tissue pathology in glioma surgery: a proof-of-concept study.

OBJECTIVE: Visual, tactile, and auditory cues are used during surgery to differentiate tissue type. Auditory cues in glioma surgery have not been studied previously. The objectives of this study were 1) to evaluate the feasibility of recording sound generated by the suction device during glioma surgery in matched tissue samples, and 2) to characterize the acoustic variation that occurs in different tissue samples. METHODS: This was a prospective observational proof-of-concept study. Recordings were attempted in 20 patients in order meet the accrual target of 10 patients with matched sound and tissue data. For each patient, three 30- to 60-second recordings were made at these sites: normal white matter, infiltrative margin, and tumor. Tissue samples at each site were then reviewed by experienced neuropathologists, and agreement with surgical identification was estimated with the kappa statistic. Acoustic parameters were characterized for each sample. RESULTS: Data from 20 patients were analyzed. Patient-related or technical issues resulted in missing data for 10 patients, but the final 10 patients had both audio and tissue data for analysis. Among all tissue samples, fair agreement was observed between surgeon identification and actual pathology (κ = 0.24, standard error 0.096, p = 0.006). Acoustic data suggested that 1) the acoustic stimulus is broadband, 2) acoustic features are somewhat consistent within cases, 3) high-entropy values indicate irregularity of sound over time, and 4) bimodal pitch distributions could differentially reflect cues of interest. CONCLUSIONS: This study supports the feasibility of collecting intraoperative data on acoustic features during glioma surgery, and it provides an example of how an analysis could be performed to compare different types of tissues.

Next-generation sequencing reveals novel mutations in a collision tumor of glioblastoma and meningioma.

Primary intracranial collision tumors are rare in patients without predisposing factors. We report such a case in a 42-year-old female who presented with headaches and altered mental status. Imaging revealed a single heterogeneous, rim-enhancing lesion in the left parieto-occipital periventricular region, involving the corpus callosum. Stereotactic biopsy demonstrated glioblastoma. Subsequent tumor resection showed histologic evidence of glioblastoma and meningioma. Next-generation sequencing was performed on both tumor components. The glioblastoma exhibited a CDKN2A homozygous deletion and novel missense mutations in TAF1L and CSMD3, while no definitive genetic alterations were identified in the meningioma. Next-generation sequencing may yield insight into molecular drivers of intracranial collision tumors and aid in identifying future therapeutic targets.