Laser Interstitial Thermal Therapy Induces Robust Local Immune Response for Newly Diagnosed Glioblastoma With Long-term Survival and Disease Control.

Laser interstitial thermal therapy (LITT) is a minimally invasive neurosurgical technique used to ablate intra-axial brain tumors. The impact of LITT on the tumor microenvironment is scarcely reported. Nonablative LITT-induced hyperthermia (33-43˚C) increases intra-tumoral mutational burden and neoantigen production, promoting immunogenic cell death. To understand the local immune response post-LITT, we performed longitudinal molecular profiling in a newly diagnosed glioblastoma and conducted a systematic review of anti-tumoral immune responses after LITT. A 51-year-old male presented after a fall with progressive dizziness, ataxia, and worsening headaches with a small, frontal ring-enhancing lesion. After clinical and radiographic progression, the patient underwent stereotactic needle biopsy, confirming an IDH-WT World Health Organization Grade IV Glioblastoma, followed by LITT. The patient was subsequently started on adjuvant temozolomide, and 60 Gy fractionated radiotherapy to the post-LITT tumor volume. After 3 months, surgical debulking was conducted due to perilesional vasogenic edema and cognitive decline, with H&E staining demonstrating perivascular lymphocytic infiltration. Postoperative serial imaging over 3 years showed no evidence of tumor recurrence. The patient is currently alive 9 years after diagnosis. Multiplex immunofluorescence imaging of pre-LITT and post-LITT biopsies showed increased CD8 and activated macrophage infiltration and programmed death ligand 1 expression. This is the first depiction of the in-situ immune response to LITT and the first human clinical presentation of increased CD8 infiltration and programmed death ligand 1 expression in post-LITT tissue. Our findings point to LITT as a treatment approach with the potential for long-term delay of recurrence and improving response to immunotherapy.

Towards the definition of progressive disease in brain metastasis treated with laser ablation: an evidence-based study.

PURPOSE: The postoperative period after laser interstitial thermal therapy (LITT) is marked by a temporary increase in volume, which can impact the accuracy of radiographic assessment. The current criteria for progressive disease (PD) suggest that a 20% increase in size of brain metastasis (BM) assessed in 6-12 weeks intervals should be considered as local progression (LP). However, there is no agreement on how LP should be defined in this context. In this study, we aimed to statistically analyze which tumor volume variations were associated with LP. METHODS: We analyzed 40 BM that underwent LITT between 2013 and 2022. For this study, LP was defined following radiographic features. A ROC curve was generated to evaluate volume change as a predictor of LP and find the optimal cutoff point. A logistic regression analysis and Kaplan Meier curves were performed to assess the impact of various clinical variables on LP. RESULTS: Out of 40 lesions, 12 (30%) had LP. An increase in volume of 25.6% from baseline within 120-180 days after LITT presented a 70% sensitivity and 88.9% specificity for predicting LP (AUC: 0.78, p = 0.041). The multivariate analysis showed a 25% increase in volume between 120 and 180 days as a negative predictive factor (p = 0.02). Volumetric changes within 60-90 days after LITT did not predict LP (AUC: 0.57; p = 0.61). CONCLUSION: Volume changes within the first 120 days after the procedure are not independent indicators of LP of metastatic brain lesions treated with LITT.

Surgical Approaches to Thalamic Gliomas: A Systematic Review.

BACKGROUND: Adult thalamic gliomas (ATGs) present a surgical challenge given their depth and proximity to eloquent brain regions. Choosing a surgical approach relies on different clinical variables such as anatomical location and size of the tumor. However, conclusive data regarding how these variables influence the balance between extent of resection and complications are lacking. We aim to systematically review the literature to describe the current surgical outcomes of ATG and to provide tools that may improve the decision-making process. METHODS: Literature regarding the surgical management of ATG patients was reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four databases were queried and a description of clinical characteristics and survival analysis were performed. An individual patient data analysis was conducted when feasible. RESULTS: A total of 462 patients were included from 13 studies. The mean age was 39.8 years with a median preoperative Karnofsky performance scale of 70. The lateral approaches were most frequently used (74.9%), followed by the interhemispheric (24.2%). Gross total and subtotal/partial resections were achieved in 81%, and 19% of all cases, respectively. New permanent neurological deficits were observed in 51/433 patients (11.8%). individual patient data was pooled from 5 studies (n = 71). In the multivariate analysis, tumors located within the posterior thalamus had worse median overall survival compared to anterior gliomas (14.5 vs. 27 months, P = 0.003). CONCLUSIONS: Surgical resection of ATGs can increase survival but at the risk of operative morbidity. Knowing which factors impact survival may allow neurosurgeons to propose a more evidence-based treatment to their patients.

Design-development of an at-home modular brain-computer interface (BCI) platform in a case study of cervical spinal cord injury.

OBJECTIVE: The objective of this study was to develop a portable and modular brain-computer interface (BCI) software platform independent of input and output devices. We implemented this platform in a case study of a subject with cervical spinal cord injury (C5 ASIA A). BACKGROUND: BCIs can restore independence for individuals with paralysis by using brain signals to control prosthetics or trigger functional electrical stimulation. Though several studies have successfully implemented this technology in the laboratory and the home, portability, device configuration, and caregiver setup remain challenges that limit deployment to the home environment. Portability is essential for transitioning BCI from the laboratory to the home. METHODS: The BCI platform implementation consisted of an Activa PC + S generator with two subdural four-contact electrodes implanted over the dominant left hand-arm region of the sensorimotor cortex, a minicomputer fixed to the back of the subject's wheelchair, a custom mobile phone application, and a mechanical glove as the end effector. To quantify the performance for this at-home implementation of the BCI, we quantified system setup time at home, chronic (14-month) decoding accuracy, hardware and software profiling, and Bluetooth communication latency between the App and the minicomputer. We created a dataset of motor-imagery labeled signals to train a binary motor imagery classifier on a remote computer for online, at-home use. RESULTS: Average bluetooth data transmission delay between the minicomputer and mobile App was 23 ± 0.014 ms. The average setup time for the subject's caregiver was 5.6 ± 0.83 min. The average times to acquire and decode neural signals and to send those decoded signals to the end-effector were respectively 404.1 ms and 1.02 ms. The 14-month median accuracy of the trained motor imagery classifier was 87.5 ± 4.71% without retraining. CONCLUSIONS: The study presents the feasibility of an at-home BCI system that subjects can seamlessly operate using a friendly mobile user interface, which does not require daily calibration nor the presence of a technical person for at-home setup. The study also describes the portability of the BCI system and the ability to plug-and-play multiple end effectors, providing the end-user the flexibility to choose the end effector to accomplish specific motor tasks for daily needs. Trial registration ClinicalTrials.gov: NCT02564419. First posted on 9/30/2015.

Supralesional Ablation Volumes Are Feasible in the Posterior Fossa and May Provide Enhanced Symptomatic Relief.

BACKGROUND: Laser interstitial thermal therapy (LITT) for posterior fossa lesions remains rare as the small size of the infratentorial compartment, proximity to the brainstem, and thickness/angulation of the occipital bone creates barriers to procedural success. Furthermore, evaluation of the effect of ablation volume on outcomes is limited. OBJECTIVE: To analyze our institutional experience with LITT in the posterior fossa stratifying perioperative and long-term outcomes by ablation volumes. METHODS: Seventeen patients with posterior fossa lesions treated with LITT from 2013 to 2020 were identified. Local progression-free survival (PFS), overall survival, steroid dependence, and edema reduction were evaluated with Kaplan-Meier analysis grouped by ablation volume. Preoperative, postoperative, and last known Karnofsky Performance Status (KPS) were compared using a matched paired t test. RESULTS: No differences in pathology, preoperative KPS, or preoperative lesion volume were found between patients with total (100%-200% increase in pre-LITT lesion volume) versus radical (>200% increase in pre-LITT lesion volume) ablations. Patients who underwent radical ablation had a higher postoperative KPS (93 vs 82, P = .02) and higher KPS (94 vs 87, P = .04) and greater reduction in perilesional edema at last follow-up (P = .01). Median follow-up was 80.8 wk. CONCLUSION: Despite obvious anatomical challenges, our results demonstrate that radical ablations are both feasible and safe in the posterior fossa. Furthermore, radical ablations may lead to greater decreases in perilesional edema and improved functional status both immediately after surgery and at last follow-up. Thus, LITT should be considered for patients with otherwise unresectable or radioresistant posterior fossa lesions.

The role of neutrophil-to-lymphocyte ratio in predicting overall survival in patients undergoing laser interstitial thermal therapy for glioblastoma.

Laser interstitial thermal therapy (LITT) offers a minimally-invasive treatment option for glioblastomas (GBM) which are relatively small or in eloquent areas. While laser ablation for malignant gliomas has been shown to be safe and effective, the role of the subsequent immune response in not well established. In this study we aim to analyze the prognostic potential of edema volume and acute inflammation, quantified as neutrophil-to-lymphocyte ratio (NLR), in predicting overall survival. Twenty-one patients were identified with new or recurrent GBMs that were candidates for LITT. Laser ablation was performed using standard solid tumor protocol for treatment volume, intensity and duration. Edema volume was quantified using MRI imaging, while retrospective chart review was performed to calculate NLR and survival. In patients treated with LITT for GBM, peri-tumoral vasogenic edema volumes did not significantly change post-operatively, p > 0.200, while NLR significantly increased, p = 0.0002. The degree of NLR increase correlated with longer overall survivals, and ROC analysis demonstrated an area under the curve of 0.827, p = 0.0112. A delta-NLR cutoff of 7.0 results in positive and negative predictive values of 78% and 75%, respectively, in predicting overall survival >1 year. Patients with with delta-NLR > 7.0 lived significantly longer that those with delta-NLR < 7.0, median survival 440 days compared to 239 days, p = 0.0297. We demonstrate preliminary data that monitoring the inflammatory response after LITT in GBM patients offers a potential prognostic measurement to assist in predicting treatment efficacy and overall survival.

Magnetic Resonance-Guided Laser Interstitial Thermal Therapy for Mesial Temporal Epilepsy: A Case Series Analysis of Outcomes and Complications at 2-Year Follow-Up.

BACKGROUND: Laser interstitial thermal therapy (LITT) presents an important new minimally invasive tool in the management of drug-resistant mesial temporal epilepsy (MTE). However, because of its relative novelty, not much is known about long-term seizure freedom rates. The objective of this study was to evaluate the postsurgical seizure outcome following LITT after a minimum follow-up period of 2 years. METHODS: Medical records of all patients who underwent LITT for MTE from 2013 to 2018 at our comprehensive epilepsy center under a single surgeon were retrospectively reviewed. Data related to demographics, presurgical evaluations, and seizure outcome were compared between seizure-free (SF) and non-seizure-free (NSF) patients. RESULTS: In all, 26 patients were identified with at least 2 years of follow-up. Mean age was 43.8 years ± 11.6 years, and 46.2% were female. After a mean follow-up time of 42.9 months (range, 24.3-58.8 months), 61.5% (16/26) were free of disabling seizures, and 26.9% (7/26) had only rare disabling seizures. Whereas seizure-freedom rates between patients with and without mesial temporal sclerosis (MTS) were not statistically different (68% vs. 43%, P = 0.23), NSF patients without MTS had a shorter median time to first seizure than did NSF patients with MTS (0.55 month vs. 10 months, log-rank test P = 0.007). Postoperative complications occurred in 2 patients (7.7%), consisting of 1 permanent and 1 transient homonymous hemianopia. CONCLUSIONS: LITT appears to be a safe and effective initial surgical option for treatment-resistant MTE. Among patients who have seizures after treatment, those without MTS appear to have seizures earlier than those with MTS.

Treatment of adult and pediatric high-grade gliomas with Withaferin A: antitumor mechanisms and future perspectives.

Resistance mechanisms employed by high-grade gliomas allow them to successfully evade current standard treatment of chemotherapy and radiation treatment. Withaferin A (WA), utilized in Ayurvedic medicine for centuries, is attracting attention for its antitumor capabilities. Here we review pertinent literature on WA as a high-grade glioma treatment, and discuss the cancerous mechanisms it affects. WA is relatively nontoxic and has shown potential in crossing the blood-brain barrier. WA prevents p53 alterations and inactivates overexpressed MDM2 through ARF and ROS production. Furthermore, WA upregulates Bax, inducing mitochondrial death cascades, inhibits mutated Akt, mTOR, and NF-κB pathways, and inhibits angiogenesis in tumors. Therapy with WA for high-grade gliomas is supported through the literature. Further investigation is warranted and encouraged to fully unearth its abilities against malignant gliomas.

Magnetic Resonance-Guided Laser Ablation for the Treatment of Recurrent Dural-Based Lesions: A Series of Five Cases.

BACKGROUND AND OBJECTIVE: Magnetic resonance-guided laser-induced thermotherapy (MR-LITT) is a minimally invasive technique that shows promise in neuro-oncology because of its superiority in delivering precise minimally invasive thermal energy with minimal collateral damage. In this analysis, we investigate initial data on the effect of MR-LITT on dural-based lesions. METHODS: Five patients were identified with dural-based lesions (4 meningiomas, 1 solitary fibrous tumor) with clear evidence of radiologic progression. In all 5 cases, the tumors were localized to the lateral convexity or paramedian locations in the supratentorial space. All patients received MR-LITT and then a follow-up magnetic resonance imaging scan at 24 hours after treatment, at 1 month, and at each subsequent follow-up visit. Local control of the ablated tumor was evaluated with radiographic follow-up and symptomatic progression-free survival was recorded. RESULTS: Five LITT treatments were performed on 5 patients with an average age of 65.2 years. The average tumor volume was 29.7 cm3 and ablation dosage was 12.4 W. On average, 80% of the pretreatment lesion volume was ablated. The mean follow-up time was 59.3 weeks. In total, 2 patients (1 with an anaplastic meningioma and 1 with a solitary fibrous tumor) had radiographic evidence of disease progression. In the observed time of the 3 patients with no progression, there was a 52% reduction in tumor volume. There were no major perioperative complications. CONCLUSIONS: MR-LITT is a promising technology for dural-based lesion treatment. This initial study demonstrates that MR-LITT is safe and offers several advantages over open surgical treatment. Randomized studies are needed to evaluate its role as a treatment adjunct.

Laser Interstitial Thermal Therapy: Lighting the Way to a New Treatment Option in Neurosurgery.

ABBREVIATIONS: LITT, laser interstitial therapyNd:YAG, neodymium-doped yttrium aluminum.

Laser Ablation of Newly Diagnosed Malignant Gliomas: a Meta-Analysis.

BACKGROUND: Magnetic resonance-guided laser-interstitial thermotherapy (MR-LITT) is a minimally invasive technique that shows promise in neuro-oncology because of its superiority in delivering precise minimally invasive thermal energy with minimal collateral damage. OBJECTIVE: In this analysis, we investigate initial data on the use of MR-LITT in the treatment of newly diagnosed high-grade gliomas. METHODS: With the use of the PubMed, OVID, and Google-scholar database systems, a comprehensive search of the English literature was performed. Eighty-five articles were identified plus 1 that is pending publication. Four articles were accounted for in this review, including 25 patients with newly diagnosed high-grade gliomas who underwent MR-LITT treatment. We evaluated safety, progression-free survival, and overall survival. RESULTS: Twenty-five patients with a mean age of 53.8 years underwent LITT treatments. On average, 82.9% of the pretreatment lesion volume was ablated. The average tumor volume treated was 16.5 cm. The mean follow-up time was 7.6 months. Median overall survival was found to be 14.2 months (range 0.1-23 months). The median progression-free survival was 5.1 months (range 2.4-23 months); however, these data are limited by the relatively short follow-up of the patients reviewed and small sample size of only 25 patients. There was 1 (3.4%) major perioperative complication, which was a central nervous system infection. CONCLUSION: MR-LITT is a promising technology for the treatment of small, yet difficult-to-treat newly diagnosed high-grade gliomas. This study demonstrates that MR-LITT is safe, and future randomized studies are needed to evaluate its role as a treatment adjunct for newly diagnosed high-grade gliomas. ABBREVIATIONS: BBB, blood-brain barrierHGG, high-grade gliomaLITT, laser-interstitial thermal therapyWHO, World Health Organization.

Use of a Mobile Intraoperative Computed Tomography Scanner for Navigation Registration During Laser Interstitial Thermal Therapy of Brain Tumors.

OBJECTIVE: In recent years laser interstitial thermal therapy (LITT) has become the ablative neurosurgical procedure of choice. Multiple methods for registration and laser fiber verification have been described, with each method requiring multiple steps and significant time expenditure. We evaluated the use of a commercially available mobile computed tomography (CT) scanner for stereotactic registration during LITT for brain tumors in an attempt to simplify the procedure and improve intraoperative awareness of laser position. METHODS: This is a retrospective chart review comparing LITT of brain tumors in 23 patients undergoing a standard protocol requiring skull pins and transport of the patient to a CT suite to obtain a reference scan compared with 14 patients in whom the Medtronic O-arm was used intraoperatively for navigation registration and confirmation of laser position. RESULTS: Total ablation of the target was achieved in all patients with no surgical complications. Total surgery time was shorter for the O-arm group than for the standard protocol group, once experience was gained with bringing the O-arm in and out of the surgical field. Return from the magnetic resonance imaging suite to the operating room for repositioning of the laser was required for 1 patient in the standard protocol group, but for no patients in the O-arm group. Once experience was gained with using the O-arm, estimated surgical costs were lower for this group. CONCLUSIONS: Use of a mobile intraoperative CT scanner for navigation registration and confirmation of laser position during LITT may play a role in streamlining the procedure and improving patient safety and comfort.

The role of magnetic resonance-guided laser ablation in neurooncology.

INTRODUCTION: The use of magnetic resonance-guided laser-induced thermal therapy (MR-LITT) as a minimally invasive method of treating intra-cranial pathology is a rapidly growing field. The use of MR-LITT in neurooncology has shown promising results; however, there has been no review to date of the current literature. METHODS: A review of the published literature regarding MR-LITT in neurooncology was performed. Studies on PubMed were included if at least one patient with a cerebral tumour or radiation necrosis was treated using quantitative MR thermography-guided LITT, as well as if either safety or outcomes were discussed. RESULTS: In treating recurrent Grade-III and -IV gliomas, we found improved median overall survival of 20.9 months from diagnosis of recurrence, which is comparable with that of 18.9 months for high-dose-rate brachytherapy and 24.4 months for repeated open surgery. Median progression-free survival (PFS) of recurrent glioma is noted to be 4.5 months. For metastatic lesions, we found a median overall survival (OS) to vary between 9.0 and 19.8 months with a PFS between 3.8 and 8.5 months. Current literature reports median OS in similar patients to lie between 7.0 and 28.6 months. Severe complication rates (with permanent deficits) are found to be between 12 and 16.7%, comparable with 11% found in literature for open surgery. CONCLUSIONS: The current literature shows that MR-LITT is safe and shows promising local tumour control rates. Larger randomised studies are warranted to further investigate this adjuvant therapy in the treatment of recurrent high-grade gliomas and metastases.