Next, I'd like to invite up Dr. Igor Oskolou for risk-adjusted overall survival for pediatric high-grade astrocytomas by location and treatment in a national cohort. Thank you. I'm Brian. I apologize for my voice. I'll be discussing quickly the survival outcomes associated with high-grade astrocytomas in the pediatric population. In the last 10 years, there's been quite a bit of expansion in our knowledge of the molecular underpinnings and the behavior of pediatric high-grade gliomas. But the specific and precise impacts of treatment and tumor characteristics on their survival, particularly for the anaplastic astrocytomas and the glioblastomas in the small population remains unclear. So we sought to investigate these questions using a national cohort. For that, we selected the National Cancer Database, which notably includes more than 70% of all newly diagnosed cancers in the United States. The NCDB has a number of key limitations which will affect our methodology, namely that all of the diagnoses are based on the old histology-only WHO definitions. And so it importantly will lack precise molecular information like IDH, histone, and BRAF mutational status. So we then queried for all newly diagnosed pediatric high-grade astrocytomas, that's either WHO grade 3 or 4, anaplastic astros, or GBMs involving the CNS. And we assessed their overall survival using Kaplan-Meier techniques, log-rank tests, and we suggested using proportional hazards. We identified more than 1,600 pediatric HGAs, a majority of which were located in the cerebral hemispheres. And their characteristics are all summarized here. For treatment, a majority of all tumors, regardless of location, receive chemo and radiation. But only a majority of the cerebral hemispheric and the cerebellar hemispheric tumors underwent resection. So here if we depict the overall survival by the location of the HGA, we see here in blue, the hemispheric tumors had the best overall survival, with a median about 24 months. And the brainstem gliomas here in green had the worst overall survival, with a median overall survival less than a year. And the diencephalic, cerebellar, and spinal cord lesions all clustering in between. We'll focus a bit on the hemispheric HGAs, the cerebrum, of which a third underwent gross total resection. And here in green, we see that they had a significantly improved overall survival compared to non-resected and subtotally resected tumors, with a median of about three years. Chemotherapy also was associated with improved survival, although these benefits might be most pronounced early on in the disease course. Whereas radiotherapy was not significantly associated with improved survival. And so in risk-adjusted multivariable analyses that included all the clinical pathological variables, we see that gross total resection was an independent predictor of improved overall survival, whereas the clinical pathological characteristics were not, other than who grade four had worse overall survival. So I'll just summarize that extended resection showed a improved benefit for overall survival in only the hemispheric tumors, whereas chemotherapy had an overall survival benefit in the hemispheric brainstem and diencephalic tumors. And then these findings and conclusions suggest that the patient characteristics and survival vary by the HGA location. That's especially relevant as we increasingly learn that different localizations have different molecular pathways that drive them. And for those tumors that were in accessible regions of the cerebral hemispheres, maximal resection should be the goal of therapy, and chemotherapy still plays a very important role in the promoted survival of these tumor types. Thank you so much. Thank you.

Dr. Igor Oskolou

pediatric high-grade astrocytomas

overall survival rates

tumor location

treatment strategies