Laser Interstitial Thermal Therapy in Glioblastoma

Abstract

Laser interstitial thermal therapy is a minimally invasive ablative technique that continues to gain popularity in treatment of a variety of intracranial and spinal disorders. In the field of neuro-oncology it continues to be used for treatment of a variety of intracranial neoplasms, including glioblastoma—the most common malignant primary brain tumor. Maximizing the extent of resection in patients with glioblastoma was shown to prolong patient survival. Many patients present, however, with tumors that are nonresectable due to proximity to eloquent cortical or subcortical areas, or involvement of deep brain struc - tures. LITT procedure, on the other hand, is minimally invasive and involves placing a laser catheter under stereotactic guidance and monitoring the size of the lesion produced as a result of laser ablation using MR thermography in real time. Therefore, a number of studies explored the potential of laser ablation to accomplish significant cytoreduction and thus potentially improve patient’s outcomes and prolong survival. The following chapter will review the principles of laser ablation and its current role in treatment of glioblastoma. was started on Keppra. Laser ablation of the lesion with a concurrent biopsy was recom-mended given the deep-seated location of the tumor. A single trajectory was used employ-ing a side firing laser (Monteris). Complete tumor coverage was achieved as indicated by inclusion of the entire tumor volume within the blue thermal damage threshold lines. She had an uneventful postoperative course. No new postoperative deficits were associated with the procedure. Pathology showed a hypercellular glial tumor with marked nuclear atypia, frequent mitoses, and vascular proliferative changes, consistent with the diagnosis of glio blastoma. A Ki-67 labeling index in excess of 30% was focally noted. Greater than 80% of tumor cells stained positively with antibody to p53. 1p/19q chromosomes were intact, and EGFR was non-amplified. Following laser treatment, the patient received chemotherapy and radiation according to Stupp protocol, followed by adjuvant temozolomide for eight cycles that was stopped due to persistent myelosuppression. She was followed with regular MRI scans of brain with great local control with nearly complete resolution of the treated lesion. Unfortunately, at 2.5 years after procedure she developed disease progression at a remote site.