TMIC-12. LITT RESULTS IN ROBUST T CELL INFILTRATION WITHIN THE TUMOR MICROENVIRONMENT IN A BRAIN METASTASIS MURINE MODEL

• Published in: Neuro-oncology (Charlottesville, Va.) Va.), 2024-11, Vol.26 (Supplement_8), p.viii300-viii300
• Main Authors: Chauhan, Anjali, Thomas, Nagheme, Frain, Matthew, Otero, Oriana Cristina, Kumar, Ravi, Tomdio, Macaulay Y, Packham, Olivia R, Bova, Frank J, Deleyrolle, Loic, Takacs, Gregory Pal, Harrison, Jeffrey K, Rahman, Maryam
• Format: Article
• Language: English
• ISSN: 1522-8517; 1523-5866
• DOI: 10.1093/neuonc/noae165.1190

Abstract INTRODUCTION Laser interstitial thermal therapy (LITT) is a novel minimally invasive neurosurgical technique used to ablate intra-axial brain tumors with real-time thermometry. The impact of LITT on the brain metastatic tumor microenvironment (TME) is unknown in patients due to limitations of tumor tissue collection post-LITT. The primary objective of this study was to describe the kinetics of immunologic infiltration within the TME in a melanoma brain metastasis model. METHOD: C57BL6 mice underwent intra-cranial implantation of B16F10-OVA tumor cells and treated with LITT using a custom-made murine LITT system developed in our laboratory. The tumors were treated to 42°C (near infra-red 1064 nm DPSS laser system) 7 days post-surgery. Tumors were collected 2 days and 10 days post-LITT for immune-phenotyping using flow cytometry. Blood was collected 6 h and 48 h post-LITT to perform the ELISA for IFN-g and TNF-a. RESULTS LITT treatment triggered a cascade of local infiltration of immune cells at different time points. 2-days post-LITT resulted in increased CD8 T cells (p