SURG-22. STAGED LASER INTERSTITIAL THERAPY (LITT) FOR THE SURGICAL TREATMENT OF INSULAR GLIOMA: A CASE SERIES WITH A NOVEL TREATMENT PARADIGM

Abstract

Abstract BACKGROUND Insular gliomas pose a significant surgical challenge due to the insula’s delicate surrounding functional and vascular anatomy. Insular gliomas are conventionally treated with open surgical resection augmented by several surgical adjuvants. Despite advancements in technology and surgical techniques, surgical resection of insular gliomas has been associated with frequent and potentially severe morbidity. Laser interstitial thermal therapy (LITT) is a novel, cytoreductive, and less-invasive treatment option for glioma. OBJECTIVE We describe the first-ever series of patients with insular glioma treated with staged LITT with or without subsequent craniotomy. METHODS A retrospective institutional database identified patients with insular glioma who underwent staged LITT treatments. Clinical, histopathological, and volumetric lesional characteristics were obtained. Procedural characteristics, morbidity, overall survival (OS), and progression-free survival (PFS) were determined. RESULTS Between 2019-2022, 11 patients with insular glioma were treated in stages with a total of 21 LITT procedures with or without subsequent craniotomy. Four patients had Diffuse Astrocytoma (IDHmt/TP53+), one Gemistocytic Astrocytoma (IDHmt/TP53+), three Anaplastic Astrocytoma (IDHmt/TP53+), one Anaplastic Oligodendroglioma (IDHmt/1p19q codel), one secondary GBM (IDHmt/TP53+), and one GBM (IDHwt/TP53-). Six patients were treated with LITT alone, while five patients were treated with LITT followed by a craniotomy for complete resection. Patients had a median tumor volume of 31.5 cm3 (9.58, 97) and a mean extent of ablation±resection of 97.68% (S.D. 5.4). At a median follow-up of 12.59 months, patients had a median PFS of 12.88 months and an OS of 14.46 months. No patients had a change in KPS following LITT. Two patients had a decrease in KPS following surgery. CONCLUSION We present the first-ever reported series of insular glioma treated with staged LITT with/without subsequent resection. We found that staged treatment of insular gliomas with LITT is safe, effective, and a minimally invasive option that avoids the potentially significant morbidity associated with conventional surgery.