Introduction: Treatment strategies for deep intracranial gliomas remain limited to stereotactic biopsy in many cases due to the morbidity of aggressive surgical resection. Since no cytoreductive therapy is offered, outcomes have been demonstrably poor compared to patients who are able to undergo primary surgical resection. In an effort to reduce morbidity and still offer cytoreductive treatment, we offer the possibility of laser interstitial thermal therapy (LITT) for the primary treatment of intracranial deep gliomas that would be otherwise unamenable for surgical resection.

Methods: We conducted an exploratory volumetric analysis on patients (n=7) who have undergone contemporaneous biopsy and laser ablation for the treatment of deep gliomas with a median tumor volume of 28 cc (range 1.2– 155 cc).

Results: In our cohort, median extent of ablation (EOA) was 98% on postoperative MRI; mean PFS was 10.2 months, and all patients remained alive at mean follow-up time of 14.4 months without any complications.

Conclusions: Although our patient series is small, we suggest that LITT (laser) for these patients can be a safe alternative cytoreductive therapy for deep surgically inaccessible gliomas. Given the known benefit of near gross total resection for high-grade gliomas, we believe LITT may improve survival for these patients and complement adjuvant treatments if patients are appropriately selected.

Patient Care: Currently, many patients with deep gliomas only receive stereotactic biopsy and adjuvant treatment without any surgical debulking. We offer LITT as an adjunct to biopsy for these lesions in hopes to improve outcomes. LITT not only offers cytoreduction but also valuable potentiation of adjuvant chemoradition by transiently disrupting the blood brain barrier. Our data demonstrated optimal ablation volumes (>98%) and suggests improved outcomes with this treatment approach.

Learning Objectives: By the conclusion of this session, participants should be able to identify a useful and safe primary treatment modality for deep surgically inaccessible intracranial gliomas.

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