EXTH-74. COOLING GLIOBLASTOMA WITH A NEURAL IMPLANT

Abstract Survival rates for glioblastoma (GBM) patients are low due to the difficulty in eradicating all tumor cells, leading to frequent recurrence. This recurrence is frequently within 2-cm from the original site. Studies indicate that supra-total resection improves survival, and non-destructive local therapies show promise in preventing GBM recurrence. Our research demonstrates that non-freezing, ‘cytostatic’ hypothermia is effective against GBM in rats and can be scaled to pig models. This method, unlike ablative cryogenic hypothermia, safely inhibits GBM growth without damaging healthy tissue. Using in vitro culture models and in vivo rat models via a Peltier device, we tested cytostatic hypothermia. This was followed by finite-element modeling (FEM) to simulate bioheat transfer in human and pig brains. The system consists of a neural implant with a multiprobe array, a Peltier chip, a water block, and an artificial internal circulation system with a piezoelectric pump. In vitro tests identified a cytostatic window of 20–25°C. Miniature Peltier devices were fabricated to achieve this in rats to inhibit GBM growth and extend survival. Rats whose tumors received cytostatic levels of hypothermia survived their full study period. FEM simulations confirmed that multiprobe arrays could cool brain tissue to 25°C without significantly raising skin temperature. Portable systems were successfully fabricated and tested in pigs, achieving safe target temperatures with minimal EEG and OCTA changes. Our findings suggest that cytostatic hypothermia can be scaled to larger animals and made implantable and portable, offering a promising non-destructive approach to halting GBM growth and prolonging survival, moving closer to becoming a viable treatment option for patients with GBM.