Introduction: Surgery for thalamic neoplasms often proves challenging due to anatomical complexity and significant risk of morbidity and mortality. Prognosis for high-grade glioma (HGG) of the thalamus remains poor. We report minimally invasive cytoreductive therapy using intraoperative real-time iMRI thermometry-guided laser interstitial thermal therapy (LITT; Neuroblate System, Monteris Medical).

Methods: Five patients with recurrent glioma or thalamic metastases (3 HGG, 2 NSCCA) underwent a total of six LITT treatments. Those with high-grade glioma had been treated with radiation and chemotherapy. Both with brain metastases had been treated with systemic chemotherapy. One underwent prior radiosurgery, and one whose tumor was too large for radiosurgery refused pre-surgical WBRT.

Results: Median age was 57; median pre-operative tumor size was 22.6 +/-9.4 cm3. All demonstrated increased regional swelling for up to 72 hours postoperatively. The median post-treatment tumor size at 72 hours was 22.6 +/-7.8 cm3; EBL <10cc; median length of stay was 5.5 days. One patient with high-grade glioma underwent bilateral treatments in two separate sessions developed hydrocephalus and expired shortly after family withdrew ventriculostomy. Another experienced transient aphasia and hemiparesis, which improved by postoperative day 14. Three had no adverse events. One with HGG was subsequently treated with bevacizumab, and the patient with adenocarcinoma, who chose to forego preoperative WBRT, underwent radiosurgical treatment. Excluding the patient transferred to hospice, median survival for the remaining patients was 109+/-278 days.

Conclusions: Laser interstitial thermotherapy (LITT) is a minimally invasive option for patients with otherwise inoperable thalamic neoplasms. All patients had transient early postoperative swelling. Nevertheless, median survival in this subset of patients was 109 days and one patient survived more than 2 years. Larger studies are necessary to identify the therapeutic efficacy, complications, and optimal indication for LITT treatment of difficult to access (DTA) tumors.

Patient Care: Presents another means for the treatment of difficult to access surgical lesions.

Learning Objectives: By the conclusion of this session, participants should be able to 1) identify the risk factors associated with treatment of thalamic neoplasms, 2) identify another effective means of treatment of these lesions, and 3) understand the risks associated with treatment with Laser Interstitial Thermotherapy (LITT).

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