2025 Poster Presentations
P089: GAMMATILE THERAPY COMBINED WITH MICROVASCULAR FREE FLAP RECONSTRUCTION IN MGMT GLIOBLASTOMA MULTIFORME: A NOVEL APPROACH TO ONCOLOGIC AND RECONSTRUCTIVE INTEGRATION
Russel T Wagner, BS; Amin B Kassam, MD; Julian E Bailes, MD; Sammy Khalili, MD; George Bobustuc, MD; Neilkamal Mundi, MD; Intent Medical Group Neurosciences, Endeavor Health
Background: Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor in adults, notorious for its rapid progression and high recurrence rates. Standard treatments involve surgery followed by chemoradiation. Delays in adjuvant treatment can result in recurrence at the resection site.
Methods: We report a novel integrative approach combining GammaTile therapy with microvascular free flap reconstruction in a 37-year-old female patient with unmethylated MGMT GBM. Post initial resection and chemoradiation, the patient presented with wound healing complications necessitating further intervention. This procedure involved tumor re-resection with implantation of cesium-131 seed-embedded GammaTiles directly into the tumor bed. Given a lack of adequate scalp soft tissue to perform primary closure, this procedure also included a microvascular free flap to ensure wound closure.
Results: This approach provided immediate and localized radiation, reducing the likelihood of tumor regrowth during the typical delay before external beam radiation therapy (EBRT). The Cs-131 GammaTiles targeted residual tumor cells with minimal exposure to surrounding healthy tissues, enhancing safety and efficacy. Importantly, immediate free flap reconstruction over the site of GammaTile implantation did not result in any wound healing complications and did not compromise the viability of the transplanted tissue.
Conclusion: We report the first case of GammaTile implantation with immediate reconstruction of the overlaying soft tissue defect with a free flap. Despite the immediate local radiation produced by the tiles abutting the free flap, there were no complications noted in the vascularity of the transplanted tissue. This finding establishes the safety of utilizing free tissue transfer during the same stage as GammaTile implantation for complex reconstruction.
Pre-operative MRI showing the tumor site before GammaTile placement and free flap reconstruction.
Post-operative MRI demonstrating the surgical site with the free flap intact following GammaTile implantation and reconstruction.
Post-operative Axial CT scan showing the placement of the titanium mesh following GammaTile implantation and free flap reconstruction.
Radiation exposure (mR/hr) at varying distances from the GammaTile, with the highest dose recorded at 3 inches. The data approximates the exposure to the free flap, which remained viable despite the proximity to the radiation source.