Laser interstitial thermal therapy for first-line treatment of insular glioma.

OBJECTIVE: Insular gliomas pose a significant surgical challenge due to the complex surrounding functional and vascular anatomy. The authors report their experience using a novel framework for the treatment of insular gliomas with laser interstitial thermal therapy (LITT) and provide representative case examples emphasizing indications, rationale, and technical pearls. METHODS: A prospectively gathered institutional database was used to identify patients with newly diagnosed insular gliomas who underwent LITT between 2015 and 2023. The proposed framework of insular glioma management is guided by tumor size and extent of extra-insular tumor involvement. Patients with tumors localized to the insula (insula-only) were treated with single-session or staged LITT. Patients with insular tumors with frontotemporal involvement (insular+) were treated with insular LITT and standard frontotemporal resection of extra-insular tumor. Clinical and volumetric lesional characteristics were analyzed, with particular emphasis on extent of cytoreductive treatment and safety. RESULTS: Of the 261 patients treated at the authors' institution with LITT between 2015 and 2023, 33 LITT procedures were identified involving 22 unique patients with treatment-naive insular gliomas. Of the 22 patients, 12 had insular-only tumors and were treated with LITT alone, while 10 patients had insular+ lesions and were treated with LITT and resection. The median tumor volume for insular-only tumors was 13.4 cm3 (IQR 10.6, 26.3 cm3), with a median extent of treatment of 100% (IQR 92.1%, 100%). Insular+ lesions were significantly larger, with a median volume of 81.2 cm3 (IQR 51.9, 97 cm3) and median extent of treatment of 96.6% (IQR 93.7%, 100%). All patients with insular-only tumors were discharged the day after ablation, while insular+ patients had significantly longer hospital stays, with 50% staying more than 3 days. Overall, 8% of insular-only patients had permanent neurological deficits compared with 33% of insular+ patients. Two patients' tumors progressed during follow-up: one patient with WHO grade 4 astrocytoma and the other with diffuse glioma not otherwise specified. Patients with grade 4 tumors had the highest rate of permanent neurological deficit (43%) and a larger decline in postoperative Karnofsky Performance Status score (p = 0.046). CONCLUSIONS: The authors present their experience using a novel insular glioma treatment paradigm that incorporates LITT into the broader framework of insular glioma surgery. Their findings suggest that insular LITT is feasible and may allow for high rates of cytoreduction while potentially ameliorating the risks of conventional insular glioma surgery.

Laser interstitial thermal therapy for deep-seated perivascular brain tumors is not associated with distal ischemia.

PURPOSE: Laser interstitial thermal therapy (LITT) is a minimally invasive cytoreductive treatment option for brain tumors with a risk of vascular injury from catheter placement or thermal energy. This may be of concern with deep-seated tumors that have surrounding end-artery perforators and critical microvasculature. The purpose of this study was to assess the risk of distal ischemia following LITT for deep-seated perivascular brain tumors. METHODS: A retrospective review of a multi-institution database was used to identify patients who underwent LITT between 2013 and 2022 for tumors located within the insula, thalamus, basal ganglia, and anterior perforated substance. Demographic, clinical and volumetric tumor characteristics were collected. The primary outcome was radiographic evidence of distal ischemia on post-ablation magnetic resonance imaging (MRI). RESULTS: 61 LITT ablations for deep-seated perivascular brain tumors were performed. Of the tumors treated, 24 (39%) were low-grade gliomas, 32 (52%) were high-grade gliomas, and 5 (8%) were metastatic. The principal location included 31 (51%) insular, 14 (23%) thalamic, 13 (21%) basal ganglia, and 3 (5%) anterior perforated substance tumors. The average tumor size was 19.6 cm3 with a mean ablation volume of 11.1 cm3. The median extent of ablation was 92% (IQR 30%, 100%). Two patients developed symptomatic intracerebral hemorrhage after LITT. No patient had radiographic evidence of distal ischemia on post-operative diffusion weighted imaging. CONCLUSION: We demonstrate that LITT for deep-seated perivascular brain tumors has minimal ischemic risks and is a feasible cytoreductive treatment option for otherwise difficult to access intracranial tumors.

Laser Interstitial Thermal Therapy for First-Line Treatment of Surgically Accessible Recurrent Glioblastoma: Outcomes Compared With a Surgical Cohort.

BACKGROUND: Laser interstitial thermal therapy (LITT) for glioblastoma (GBM) has been reserved for poor surgical candidates and deep "inoperable" lesions. We present the first reported series of LITT for surgically accessible recurrent GBM (rGBM) that would otherwise be treated with surgical resection. OBJECTIVE: To evaluate the use of LITT for unifocal, lobar, first-time rGBM compared with a similar surgical cohort. METHODS: A retrospective institutional database was used to identify patients with unifocal, lobar, first-time rGBM who underwent LITT or resection between 2013 and 2020. Clinical and volumetric lesional characteristics were compared between cohorts. Subgroup analysis of patients with lesions ≤20 cm 3 was also completed. Primary outcomes were overall survival and progression-free survival. RESULTS: Of the 744 patients with rGBM treated from 2013 to 2020, a LITT cohort of 17 patients were compared with 23 similar surgical patients. There were no differences in baseline characteristics, although lesions were larger in the surgical cohort (7.54 vs 4.37 cm 3 , P = .017). Despite differences in lesion size, both cohorts had similar extents of ablation/resection (90.7% vs 95.1%, P = .739). Overall survival (14.1 vs 13.8 months, P = .578) and progression-free survival (3.7 vs 3.3 months, P = 0. 495) were similar. LITT patients had significantly shorter hospital stays (2.2 vs 3.0 days, P = .004). Subgroup analysis of patients with lesions ≤20 cm 3 showed similar outcomes, with LITT allowing for significantly shorter hospital stays. CONCLUSION: We found no difference in survival outcomes or morbidity between LITT and repeat surgery for surgically accessible rGBM while LITT resulted in shorter hospital stays and more efficient postoperative care.

Genomic Biomarkers of Meningioma: A Focused Review.

Meningiomas represent a phenotypically and genetically diverse group of tumors which often behave in ways that are not simply explained by their pathologic grade. The genetic landscape of meningiomas has become a target of investigation as tumor genomics have been found to impact tumor location, recurrence risk, and malignant potential. Additionally, targeted therapies are being developed that in the future may provide patients with personalized chemotherapy based on the genetic aberrations within their tumor. This review focuses on the most common genetic mutations found in meningiomas of all grades, with an emphasis on the impact on tumor location and clinically relevant tumor characteristics. NF-2 and the non-NF-2 family of genetic mutations are summarized in the context of low-grade and high-grade tumors, followed by a comprehensive discussion regarding the genetic and embryologic basis for meningioma location and phenotypic heterogeneity. Finally, targeted therapies based on tumor genomics currently in use and under investigation are reviewed and future avenues for research are suggested. The field of meningioma genomics has broad implications on the way meningiomas will be treated in the future, and is gradually shifting the way clinicians approach this diverse group of tumors.

Developing Real-world Evidence-Ready Datasets: Time for Clinician Engagement.

PURPOSE OF REVIEW: Real-world data (RWD) applications in healthcare that support learning health systems and pragmatic clinical trials are gaining momentum, largely due to legislation supporting real-world evidence (RWE) for drug approvals. Clinical notes are thought to be the cornerstone of RWD applications, particularly for conditions with limited effective treatments, extrapolation of treatments from other conditions, or heterogenous disease biology and clinical phenotypes. RECENT FINDINGS: Here, we discuss current issues in applying RWD captured at the point-of-care and provide a framework for clinicians to engage in RWD collection. To achieve clinically meaningful results, RWD must be reliably captured using consistent terminology in the description of our patients. RWD complements traditional clinical trials and research by informing the generalizability of results, generating new hypotheses, and creating a large data network for scientific discovery. Effective clinician engagement in the development of RWD applications is necessary for continued progress in the field.