Search

Background Glioblastoma (GBM) is a malignant brain tumor that is common and fatal among adults. The standard treatment for GBM involves chemoradiation per Stupp's protocol and additional chemotherapy regimens. However, Stereotactic Radiosurgery (SRS) is frequently used as a single-fraction treatment for punctate recurrent GBM to the contrast-enhancing target on T1 MRI scan without prior assessment of its efficacy. Objective This study aimed to evaluate the safety and efficacy of SRS for patients with distant punctate recurrent IDH-wild type (wt) GBM. Method This retrospective study analyzed the clinical and radiological outcomes of patients with distant punctate recurrent IDH-wt GBM who underwent CyberKnife SRS at the institute between 2013 and 2022. Results A total of five patients (median age of 53 years) with nine lesions were treated with a median margin dose of 20 Gy. The results indicated that SRS, delivered as a single fraction, did not provide good local tumor control. The 3-, 6-, and 12-month local tumor control rates were 77.8%, 66.7%, and 26.7%, respectively. Median progression-free survival (PFS) was 7 months, and median overall survival (OS) was 35 months. Interestingly, the only lesion that did not show radiological progression was not associated with the T2-FLAIR hyperintense area surrounding the original tumor in the MRI. None of the patients presented adverse radiation effects. Conclusion SRS as a treatment for distant punctate recurrent IDH-wt GBM may lead to limited benefit in terms of local tumor control. Expanding the radiosurgical field to consider the T2-FLAIR hyperintense area may be necessary to improve local tumor control and survival outcomes. Further research is needed to improve SRS outcomes by developing new contouring and dosing strategies.

Introduction Stereotactic radiosurgery (SRS) has been an attractive treatment modality for both cranial and spinal hemangioblastomas, especially for multiple lesions commonly associated with von Hippel-Lindau (VHL) disease. This study aims to provide the largest long-term analysis of treatment efficacy and adverse effects of SRS for cranial and spinal hemangioblastomas at a single institution. Methods We evaluated the clinical and radiological outcomes of patients with hemangioblastomas treated with CyberKnife SRS at our institute from 1998 to 2022. The follow-up data were available for 135 hemangioblastomas in 35 patients. Twenty-eight patients had 123 hemangioblastomas associated with VHL and 7 had 12 sporadic hemangioblastomas. The median age was 36 years and the median tumor volume accounted for 0.4 cc. The SRS was administered with the median single-fraction equivalent dose (SFED) of 18 Gy to the 77% median isodose line. Results At a median follow-up of 57 months (range: 3-260), only 20 (16.2%) of the VHL-associated and 1 (8.3%) sporadic hemangioblastomas progressed. The 5-year local tumor control (LTC) rate was 91.3% for all hemangioblastomas, 91.7% among the sporadic lesions, and 92.9% in VHL patients. SRS improved tumor-associated symptoms of 98 (74.8%) of 131 symptomatic hemangioblastomas, including headache, neck pain, dizziness, visual disturbances, dysesthesia, ataxia, motor impairment, seizures, and dysphagia. Two patients developed radiation necrosis (5.7%) and 1 of them required surgical resection. Conclusion SRS is a safe and effective treatment option for patients with hemangioblastomas in critical locations such as the brainstem, cervicomedullary junction, and spinal cord, and in patients with multiple hemangioblastomas associated with VHL disease.

Immune checkpoint inhibitors (ICIs) are an emerging tool in the treatment of brain metastases (BMs), Stereotactic radiosurgery (SRS), traditionally used for BMs, elicits an immune brain response and can act synergistically with ICIs. We aim to investigate the efficacy of ICI administered with SRS and determine the impact of timing on BM response.A systematical search was performed to identify potential studies concerning BMs managed with SRS alone or with SRS + ICI with relative timing administration (ICI concurrent with SRS, ICI nonconcurrent with SRS, SRS before ICI, SRS after ICI). The overall survival (OS), 12-month OS, local progression-free survival (LPFS), 12-month local brain control (LBC), distant progression-free survival (DPFS), 12-month distant brain control (DBC), and adverse events (intracranial hemorrhage, radionecrosis) were analyzed using the random-effects model.A total of 16 retrospective studies with 1356 BM patients were included. Compared to nonconcurrent therapy, concurrent therapy revealed a significantly longer OS (HR= 1.43;The combination of SRS with ICI improves patients' clinical and radiological outcomes. The effectiveness of the combination is subject to the identification of an optimal therapeutic window.

OBJECTIVE Microsurgical resection of arteriovenous malformations (AVMs) can be aided by staged treatment consisting of stereotactic radiosurgery followed by resection in a delayed fashion. This approach is particularly useful for high Spetzler-Martin (SM) grade lesions because radiosurgery can reduce flow through the AVM, downgrade the SM rating, and induce histopathological changes that additively render the AVM more manageable for resection. The authors present their 28-year experience in managing AVMs with adjunctive radiosurgery followed by resection. METHODS The authors retrospectively reviewed records of patients treated for cerebral AVMs at their institution between January 1990 and August 2019. All patients who underwent stereotactic radiosurgery (with or without embolization), followed by resection, were included in the study. Of 1245 patients, 95 met the eligibility criteria. Univariate and multivariate regression analyses were performed to assess relationships between key variables and clinical outcomes. RESULTS The majority of lesions treated (53.9%) were high grade (SM grade IV–V), 31.5% were intermediate (SM grade III), and 16.6% were low grade (SM grade I–II). Hemorrhage was the initial presenting sign in half of all patients (49.5%). Complete resection was achieved among 84% of patients, whereas 16% had partial resection, the majority of whom received additional radiosurgery. Modified Rankin Scale (mRS) scores of 0–2 were achieved in 79.8% of patients, and 20.2% had poor (mRS scores 3–6) outcomes. Improved (44.8%) or stable (19%) mRS scores were observed among 63.8% of patients, whereas 36.2% had a decline in mRS scores. This includes 22 patients (23.4%) with AVM hemorrhage and 6 deaths (6.7%) outside the perioperative period but prior to AVM obliteration. CONCLUSIONS Stereotactic radiosurgery is a useful adjunct in the presurgical management of cerebral AVMs. Multimodal therapy allowed for high rates of AVM obliteration and acceptable morbidity rates, despite the predominance of high-grade lesions in this series of patients.

OBJECTIVE The CyberKnife (CK) has emerged as an effective frameless and noninvasive method for treating a myriad of neurosurgical conditions. Here, the authors conducted an extensive retrospective analysis and review of the literature to elucidate the trend for CK use in the management paradigm for common neurosurgical diseases at their institution. METHODS A literature review (January 1990–June 2019) and clinical review (January 1999–December 2018) were performed using, respectively, online research databases and the Stanford Research Repository of patients with intracranial and spinal lesions treated with CK at Stanford. For each disease considered, the coefficient of determination (r2) was estimated as a measure of CK utilization over time. A change in treatment modality was assessed using a t-test, with statistical significance assessed at the 0.05 alpha level. RESULTS In over 7000 patients treated with CK for various brain and spinal lesions over the past 20 years, a positive linear trend (r2 = 0.80) in the system's use was observed. CK gained prominence in the management of intracranial and spinal arteriovenous malformations (AVMs; r2 = 0.89 and 0.95, respectively); brain and spine metastases (r2 = 0.97 and 0.79, respectively); benign tumors such as meningioma (r2 = 0.85), vestibular schwannoma (r2 = 0.76), and glomus jugulare tumor (r2 = 0.89); glioblastoma (r2 = 0.54); and trigeminal neuralgia (r2 = 0.81). A statistically significant difference in the change in treatment modality to CK was observed in the management of intracranial and spinal AVMs (p < 0.05), and while the treatment of brain and spine metastases, meningioma, and glioblastoma trended toward the use of CK, the change in treatment modality for these lesions was not statistically significant. CONCLUSIONS Evidence suggests the robust use of CK for treating a wide range of neurological conditions.

Purpose/Objectives Combination BRAF (vemurafenib, dabrafenib, or encorafenib) plus MEK (trametinib, cobimetinib, or binimetinib) inhibitor therapy is now widely used in the treatment of metastatic melanoma. However, data for intracranial response to these drugs are limited. We aimed to evaluate the intracranial efficacy of BRAF plus MEK inhibitors in patients with BRAF-mutant melanoma with brain metastases (BM) and to determine patterns of failure of these new agents to inform optimal integration of local intracranial therapy. Materials and methods We retrospectively reviewed charts of patients with BRAF-mutant melanoma with metastasis to the brain with at least one untreated brain metastasis at the time of initiation of BRAF plus MEK inhibitors at our institution from 2006 to 2020. We collected per-patient and per-lesion data on demographics, treatment modality, and outcomes. The cumulative incidence of local (LF), distant intracranial (DF), and extracranial failure (EF) were calculated with competing risk analysis with death as a competing risk and censored at the last brain MRI follow-up. LF was calculated on a per-lesion basis while DF and EF were calculated on a per-patient basis. DF was defined as any new intracranial lesions. Overall survival (OS) was analyzed using Kaplan-Meier. Logistic regression was used to identify predictors for LF. Results We identified 10 patients with 63 untreated brain metastases. The median age was 50.5 years. The median sum of the diameters of the five largest untreated brain metastases per patient was 20 mm (interquartile range 15-39 mm) and the median diameter for all measurable lesions was 4 mm. Median follow-up time was 9.0 months (range 1.4 months-46.2 months). Median OS was 13.6 months. The one-year cumulative incidence of LF, DF, and EF was 17.1%, 88.6, and 71.4%, respectively. The median time to LF, DF, and EF from the start of BRAF plus MEK inhibitors was 9.0 months, 4.7 months, and 7.0 months, respectively. The larger size of the BM was associated with LF on univariate analysis (odds ratio 1.13 per 1 mm increase in diameter, 95% confidence interval 1.019 to 1.308, p0.02). Two (20%) patients eventually received stereotactic radiosurgery, and 2 (20%) received whole-brain radiotherapy for intracranial progression. Conclusion Although patients with BRAF-mutant melanoma with BM had fair local control on BRAF plus MEK inhibitors, the competing risk of death and distant intracranial and extracranial progression was high. Patients with larger brain metastases may benefit from local therapy.

OBJECTIVES We investigated differences in quality of life (QoL) in patients enrolled on a phase I/II dose-escalation study of 3-fraction resection cavity stereotactic radiosurgery (SRS) for large brain metastases. METHODS Eligible patients had 1 to 4 brain metastases, one of which was a resection cavity 4.2 to 33.5 cm3. European Organization for Research and Treatment of Cancer (EORTC) quality of life questionnaires core-30 (QLQ-30) and brain cancer specific module (QLQ-BN20) were obtained before SRS and at each follow-up. Nine scales were analyzed (global health status; physical, social, and emotional functioning; motor dysfunction, communication deficit, fatigue, insomnia, and future uncertainty). QoL was assessed with mixed effects models. Differences ≥10 points with q-value (adjusted P-value to account for multiplicity of testing)

BACKGROUND To better counsel vestibular schwannoma patients, it is necessary to understand the tumor control rates of stereotactic radiosurgery (SRS). OBJECTIVES To determine tumor control rates, factors determining control and complication rates following SRS. METHODS Tertiary hospital retrospective cohort. RESULTS 579 tumors (576 patients) were treated with SRS. 477 tumors (474 patients, 82%) had ≥1 year follow up and 60% (344) ≥3 years follow up. 88% of tumors had primary SRS and 6.7% salvage SRS. Median follow up time was 4.6 years. At 3 years, the tumor control rate of primary SRS was 89% (258 of 290) in sporadic tumors compared to 43% in Neurofibromatosis type II (3 of 17) (p

Objective Financial toxicity associated with cancer treatment has a deleterious impact on patient outcomes but has not been well characterized among patients with metastatic cancers. We characterize the extent of financial toxicity among this population and identify factors associated with financial toxicity. Methods We prospectively surveyed adult patients with brain and spine metastases who received radiosurgery at a large academic medical center between January 2018 and December 2019. Financial toxicity was measured with the Personal Financial Wellness (PFW) scale. Results In total, 93 patients were included, with a median survival of 17.7 months. Most patients had private insurance (47%) or Medicare with supplementary insurance (42%), whereas 11% of patients were uninsured or insured by Medicaid/Medicare/Veterans Affairs. Of patients, 60% were primary income earners, of whom 52% had dependents. The median PFW score was 7.0 (interquartile range, 5.1–9.1), with financial toxicity reported in 23 patients (25%). After adjusting for age and education level, private insurance (odds ratio [OR], 0.28; P = 0.080) was associated with a lower likelihood of financial toxicity. Having ≥1 emergency department visit (OR, 3.87; P = 0.024) and a cancer-related change in employment status (OR, 3.63; P = 0.036) were associated with greater likelihood of reporting financial toxicity. Conclusions Most patients with cancer with brain and spine metastases with a poor prognosis treated at a tertiary center are primary income earners and experience financial toxicity. Further studies are warranted to assess the longitudinal impact of financial toxicity in patients with metastatic cancer, particularly those with ≥1 emergency department visit and a cancer-related change in employment status.

Background Radiation therapy for intracranial lesions is constrained by dose to neurologic organs at risk. Case Description We report 2 cases, a newly diagnosed chondrosarcoma and a previously irradiated meningioma, with tumors that abutted the optic chiasm following subtotal resection. Definitive radiotherapy would have required either undercoverage of the tumor or treatment of the chiasm with doses posing an unacceptable risk of blindness. Therefore, the patients underwent open surgery with placement of an abdominal fat autograft to provide space between the tumor and the optic structures at risk. Patients received definitive fractionated stereotactic radiotherapy. For each patient, we retrospectively compared the treated plan (with fat autograft) to a second plan generated using the pre-autograft imaging, maintaining similar tumor coverage. For the chondrosarcoma, the fat autograft reduced the optic chiasm maximum dose by 21% (70.4 Gy to 55.3 Gy). For the reirradiated peri-optic meningioma, the optic chiasm maximum dose was reduced by 10% (50.8 Gy to 45.9 Gy), the left optic nerve by 17% (48.9 Gy to 40.4 Gy), and the right optic nerve by 30% (32.3 Gy to 22.6 Gy). Conclusions We demonstrate the utility of abdominal fat autograft placement to maximize coverage of tumor while minimizing dose to intracranial organs at risk.

Objective Immunotherapy for patients with melanoma with brain metastasis has significantly improved outcomes; however, it has also been characterized by potentially dangerous immune-related adverse events (IRAEs). Several reports have suggested that these reactions can precede improved treatment responses. For intracranial disease control, we sought to identify if such an association exists. Methods We conducted a retrospective chart review of patients with melanoma who underwent immunotherapy treatment after diagnosis of brain metastasis. The study cohort was then stratified into 2 groups based on their history of developing an IRAE that prompted discontinuation of that regimen. The primary outcome variable included intracranial progression-free survival (PFS). Kaplan-Meier and Cox proportional hazard analyses were used to evaluate survival and predictors of outcomes. Results Fifty-two patients met the inclusion criteria, 17 of whom experienced severe IRAEs that led to discontinuation of immunotherapy. Median intracranial PFS was 19.9 versus 10.5 months (P = 0.053) in patients who did and did not experience severe IRAEs prompting discontinuation, respectively. No additional outcome benefits were identified for systemic PFS or overall survival (mean, 33.1 months and 27.6 months, respectively). Multivariable analysis identified BRAF mutation status as a negative prognosticator of brain progression (P = 0.013; hazard ratio, 3.90). Initial treatment with BRAF inhibitor was also a negative predictor of all-cause mortality (P = 0.015; hazard ratio, 10.73). Conclusions Immune-related adverse events may signify an underlying immunogenic response that has intracranial disease control benefits. Despite their associated side effects, immunotherapies continue to show promising outcomes as a first-line agent for melanoma with brain metastasis.

Introduction Dural arteriovenous fistulae (DAVF) are vascular lesions with arteriovenous shunting that may be treated with surgical obliteration or endovascular embolization. Some DAVF, such as anterior cranial fossa DAVF (AC-DAVF) derive their arterial supply from ophthalmic artery branches in nearly all cases, and trans-arterial embolization carries a risk of vision loss. We determined the efficacy and safety of trans-ophthalmic artery embolization of DAVF. Materials and methods We performed a retrospective cohort study of all patients with DAVF treated by trans-ophthalmic artery embolization from 2012 to 2020. Primary outcome was angiographic cure of the DAVF. Secondary outcomes included vision loss, visual impairment, orbital cranial nerve injury, stroke, modified Rankin Scale at 90-days, and mortality. Results 12 patients met inclusion criteria (9 males; 3 females). 10 patients had AC-DAVF. Patient age was 59.7 ± 9.5 (mean ± SD) years. Patients presented with intracranial hemorrhage (4 patients), headache (4 patients), amaurosis fugax (1 patients), or were incidentally discovered (2 patients). DAVF Cognard grades were: II (1 patient), III (6 patients), and IV (5 patients). DAVF were embolized with Onyx (10 patients), nBCA glue (1 patient), and a combination of coils and Onyx (1 patient). DAVF cure was achieved in 11 patients (92%). No patients experienced vision loss, death, or permanent disability. One patient experienced a minor complication of blurry vision attributed to posterior ischemic optic neuropathy. 90-day mRS was 0 (10 patients) and 1 (2 patients). Conclusions Trans-ophthalmic artery embolization is an effective and safe treatment for DAVF.

Purpose Although consensus guidelines for postresection stereotactic radiosurgery (SRS) for brain metastases recommend the surgical corridor leading to the resection cavity be included in the SRS plan, no study has reported patterns of tumor recurrence based on inclusion or exclusion of the corridor as a target. We reviewed tumor control and toxicity outcomes of postresection SRS for deep brain metastases based on whether or not the surgical corridor was targeted. Materials and Methods We retrospectively reviewed patients who had resected brain metastases treated with SRS between 2007 and 2018 and included only “deep” tumors (defined as located ≥1.0 cm from the pial surface before resection). Results In 66 deep brain metastases in 64 patients, the surgical corridor was targeted in 43 (65%). There were no statistical differences in the cumulative incidences of progression at 12 months for targeting versus not targeting the corridor, respectively, for overall local failure 2% (95% confidence interval [CI], 0%-11%) versus 9% (95% CI, 1%-25%; P = .25), corridor failure 0% (95% CI, 0%-0%) versus 9% (95% CI, 1%-25%; P = .06), cavity failure 2% (95% CI, 0%-11%) versus 0% (95% CI, 0%-0%; P = .91), and adverse radiation effect 5% (95% CI, 1%-15%) versus 13% (95% CI, 3%-30%; P = .22). Leptomeningeal disease (7%; 95% CI, 2%-18%) versus 26% (95% CI, 10%-45%; P = .03) was higher in those without the corridor targeted. Conclusions Omitting the surgical corridor in postoperative SRS for resected brain metastases was not associated with statistically significant differences in corridor or cavity recurrence or adverse radiation effect. As seen in recent prospective trials of postresection SRS, the dominant pattern of progression is within the resection cavity; omission of the corridor would yield a smaller SRS volume that could allow for dose escalation to potentially improve local cavity control.

Head and neck paragangliomas (HNPs) are rare, usually benign hyper vascularized neuroendocrine tumors that traditionally have been treated by surgery, with or without endovascular embolization, or, more recently stereotactic radiosurgery (SRS). The aim of our study is to determine the clinical and radiographic effectiveness of SRS for treatment of HNPs. A systematic search of electronic databases was performed, and 37 articles reporting 11,174 patients (1144 tumors) with glomus jugulare (GJT: 993, 86.9%), glomus tympanicum (GTT: 94, 8.2%), carotid body tumors (CBTs: 28, 2.4%), and glomus vagale (GVT: 16, 1.4%) treated with SRS definitively or adjuvantly were included. The local control (LC) was estimated from the pooled analysis of the series, and its association with SRS technique as well as demographic and clinical factors was analyzed. The median age was 56 years (44–69 years). With a median clinical and radiological follow-up of 44 months (9–161 months), LC was 94.2%. Majority of the patients (61.0%) underwent Gamma Knife Radiosurgery (GKS), but there was no statistically significant difference in LC depending upon the SRS technique (p = 0.9). Spearmen’s correlation showed that LC was strongly and negatively correlated with multiple parameters, which included female gender (r = − 0.4, p = 0.001), right-sided tumor (r = − 0.3, p = 0.03), primary SRS (r = − 0.5, p ≤ 0.001), and initial clinical presentation of hearing loss (r = − 0.4, p = 0.001). To achieve a LC ≥ 90%, a median marginal dose (Gy) of 15 (range, 12–30 Gy) was required. The results corroborate that SRS in HNPs is associated with good clinical and radiological outcome.

Background and purpose Brain arteriovenous malformation (AVM) treatment by stereotactic radiosurgery (SRS) is effective, but AVM obliteration following SRS may take two years or longer. MRI with arterial-spin labeling (ASL) may detect brain AVMs with high sensitivity. We determined whether brain MRI with ASL may accurately detect residual AVM following SRS treatment. Materials and methods We performed a retrospective cohort study of patients who underwent brain AVM evaluation by DSA between June 2010 and June 2015. Inclusion criteria were: (1) AVM treatment by SRS, (2) follow-up MRI with ASL at least 30 months after SRS, (3) DSA within 3 months of the follow-up MRI with ASL, and (4) no intervening AVM treatment between the MRI and DSA. Four neuroradiologists blindly and independently reviewed follow-up MRIs. Primary outcome measure was residual AVM indicated by abnormal venous ASL signal. Results 15 patients (12 females, mean age 29 years) met inclusion criteria. There were three posterior fossa AVMs and 12 supratentorial AVMs. Spetzler–Martin (SM) Grades were: SM1 (8%), SM2 (33%), SM3 (17%), SM4 (25%), and SM5 (17%). DSA demonstrated residual AVM in 10 patients. The pooled sensitivity, specificity, positive predictive value, and negative predictive value of venous ASL signal for predicting residual AVM were 100% (95% CI: 0.9-1.0), 95% (95% CI: 0.7–1.0), 98% (95% CI: 0.9–1.0), and 100% (95% CI: 0.8–1.0), respectively. High inter-reader agreement as found by Fleiss’ Kappa analysis (k = 0.92; 95% CI: 0.8–1.0; P Conclusions ASL is highly sensitive and specific in the detection of residual cerebral AVM following SRS treatment.

Background Historically, it is stated that large intracranial tumors, herein defined as a maximum dimension of ≥3 cm or tumor volume ≥14.2 cm3, are not candidates for stereotactic radiosurgery (SRS). We report outcomes of patients with large benign intracranial tumors treated with SRS. Methods With institutional review board approval, we retrospectively identified 74 patients with large benign intracranial tumors (59 meningiomas, 9 vestibular schwannomas, and 6 glomus jugulare tumors) treated with robotic SRS (2007–2018). Patients received definitive SRS in 47.3% of the cases, adjuvant to surgical resection in 44.6%, and salvage after past radiation treatment in 8.1%. A median tumor volume of 16.0 cm3 (range, 10.1–65.5 cm3) received a median dose of 24.0 Gy (range, 14.0–30.0 Gy) in a median of 3 fractions (range, 1–5), for a median single fraction equivalent dose (with alpha/beta of 3) of 14.8 Gy (range, 11.3–18.0 Gy). The Kaplan-Meier estimate of tumor local control (LC) was calculated from date of SRS. Results With a median clinical follow-up of 32.8 months (range, 0.6–125.9 months) and median radiologic follow-up of 28.5 months (range, 0.6–121.4 months), LC was 96.5% (95% confidence interval, 92.4%–100%) at 3 years and 91.7% (95% confidence interval, 87.6%–95.7%) at 5 years. Adverse radiation effect (ARE) was seen in 10 patients (13.5%) at a median of 13.5 months (range, 7.8–34.5 months). ARE occurred in 9% of those with prior treatment compared with 5% who were radiation-naive (P = 0.23). With 236.4 person-years of follow-up, no secondary malignancies were seen. Conclusions Despite the historical adage, we find that SRS provides high rates of LC for these large tumors, with rates of ARE similar to historical reports of SRS for smaller benign tumors.

BACKGROUND Radiosurgical treatment of brain metastases is usually performed without brain tissue confirmation. While it is extremely rare for glioblastoma to develop concurrently in patients with brain metastases, they can look radiographically similar, and recognition is important because it alters management and prognosis. The synchronous presence of brain metastases and glioblastoma has not been published to date in the literature, making this a rare illustrative case. OBSERVATIONS A 70-year-old female had lung biopsy-proven metastatic lung adenocarcinoma and multiple brain metastases. Her treatment course included initial carboplatin, pemetrexed, and bevacizumab followed by maintenance nivolumab, and she underwent stereotactic radiosurgery to the multiple brain metastases. During interval radiological surveillance, one lesion in the right temporal lobe was noted to slowly progress associated with development of significant perilesional edema causing midline shift despite repeated stereotactic radiosurgical treatments. Biopsy of this lesion revealed glioblastoma, IDH wildtype. LESSONS Glioblastomas and brain metastases have similar radiological features, so the possibility of incorrect diagnosis needs to be considered for all lesions with interval growth poststereotactic radiosurgery. Biopsy and/or resection/laser ablation should be considered prior to reirradiation.

OBJECTIVE Trigeminal neuralgia (TN) secondary to tumor represents a rare and diverse entity, and treatment for secondary TN remains controversial. This report reviews a single institution’s experience in treating secondary TN with stereotactic radiosurgery (SRS) and focuses on the durability of pain relief with respect to various treatment targets, i.e., the trigeminal nerve, offending tumor, or both. METHODS Between the years 2009 and 2021, 21 patients with TN secondary to benign (n = 13) or malignant (n = 8) tumors underwent SRS. Barrow Neurological Institute (BNI) pain intensity scale scores were collected from patient electronic medical records at baseline, initial follow-up, and 1 and 3 years post-SRS. The interval change in BNI scale score (ΔBNI) at the various follow-up time points was also calculated to assess the durability of pain relief following SRS. RESULTS The median follow-up period was 24 (range 0.5–155) months. Five patients (24%) received treatment to the trigeminal nerve only, 10 (48%) received treatment to the tumor only, and 6 (29%) had treatment to both the nerve and tumor. The overall radiation dosage ranged from 14 to 60 Gy delivered in 1–5 fractions, with a median overall dose of 26 Gy. The median dose to the tumor was 22.5 (range 14–35) Gy, delivered in 1–5 fractions. Of the treatments targeting the tumor, 25% were delivered in a single fraction with doses ranging from 14 to 20 Gy, 60% were delivered in 3 fractions with doses ranging from 18 to 27 Gy, and 15% were delivered in 5 fractions with doses ranging from 25 to 35 Gy. The most common dose regimen for tumor treatment was 24 Gy in 3 fractions. The median biologically effective dose (with an assumed alpha/beta ratio of 10 [BED10]) for tumor treatments was 43.1 (range 13.3–60.0) Gy. There was a significant difference in the proportion of patients with recurrent pain (ΔBNI score ≥ 0) at the time of last follow-up across the differing SRS treatment targets: trigeminal nerve only, tumor only, or both (p = 0.04). At the time of last follow-up, the median ΔBNI score after SRS to the nerve only was −1, 0 after SRS to tumor only, and −2 after SRS to both targets. CONCLUSIONS SRS offers clinical symptomatic benefit to patients with TN secondary to tumor. For optimal pain relief and response durability, treatment targeting both the tumor and the trigeminal nerve appears to be most advantageous.

To better counsel vestibular schwannoma patients, it is necessary to understand the tumor control rates of stereotactic radiosurgery (SRS).To determine tumor control rates, factors determining control and complication rates following SRS.Tertiary hospital retrospective cohort.579 tumors (576 patients) were treated with SRS. 477 tumors (474 patients, 82%) had ≥1 year follow up and 60% (344) ≥3 years follow up. 88% of tumors had primary SRS and 6.7% salvage SRS. Median follow up time was 4.6 years. At 3 years, the tumor control rate of primary SRS was 89% (258 of 290) in sporadic tumors compared to 43% in Neurofibromatosis type II (3 of 17) (p 0.01). Our bivariable survival data analysis showed that Neurofibromatosis type II, documented pre-SRS growth, tumor measured by maximum dimension, SRS given as nonprimary treatment increased hazard of failure to control. There was one case of malignancy and another of rapid change following intra-tumoral hemorrhage. For tumors undergoing surgical salvage (25 of 59), 56% had a total or near-total resection, 16% had postoperative CSF leak, with 12% new facial paralysis (House-Brackmann grade VI) and worsening of facial nerve outcomes (House-Brackmann grade worse in 59% at 12 mo).Control of vestibular schwannoma after primary SRS occurs in the large majority. Salvage surgical treatment was notable for higher rates of postoperative complications compared to primary surgery reported in the literature.

OBJECTIVEArteriovenous malformations (AVMs) of the basal ganglia and thalamus are particularly difficult lesions to treat, accounting for 3%–13% of all AVMs in surgical series and 23%–44% of malformations in radiosurgery series. The goal of this study was to report the results of multimodal management of basal ganglia and thalamic AVMs and investigate the factors that influence radiographic cure and good clinical outcomes.METHODSThis study was a retrospective analysis of a prospectively maintained database of all patients treated at the authors’ institution. Clinical, radiological, follow-up, and outcome data were analyzed. Univariate and multivariate analyses were conducted to explore the influence of various factors on outcome.RESULTSThe results and data analysis pertaining to 123 patients treated over 32 years are presented. In this cohort, radiographic cure was achieved in 50.9% of the patients. Seventy-five percent of patients had good clinical outcomes (stable or improved performance scores), whereas 25% worsened after treatment. Inclusion of surgery and radiosurgery independently predicted obliteration, whereas nidus diameter and volume predicted clinical outcomes. Nidus volume/diameter and inclusion of surgery predicted the optimal outcome, i.e., good clinical outcomes with lesion obliteration.CONCLUSIONSGood outcomes are possible with multimodal treatment in these complex patients. Increasing size and, by extension, higher Spetzler-Martin grade are associated with worse outcomes. Inclusion of multiple modalities of treatment as indicated could improve the chances of radiographic cure and good outcomes.

Background Immune checkpoint inhibitors (ICIs) and stereotactic radiosurgery (SRS) are increasingly used together to manage brain metastases (BMs). We assessed adverse radiation effect, disease control, and overall survival in patients with BMs who received SRS with anticytotoxic T-lymphocyte–associated protein 4 and/or anti– programmed cell death protein receptor/ligand therapies. Methods We retrospectively reviewed the records of patients with intact or resected BMs treated with SRS and ICIs within 5 months of SRS between 2010 and 2018. Patients were defined as receiving concurrent SRS and ICI if a dose of ICI was given within 4 weeks of SRS. Local failure, distant intracranial failure, extracranial failure, and adverse radiation effect were assessed using cumulative incidence rates and competing risk regressions with death as a competing risk. Overall survival was assessed using the Kaplan-Meier method and Cox proportional hazards models. Results A total of 97 patients with 580 BMs were included in our analysis. Competing risk analyses showed that concurrent SRS-ICI therapy is associated with higher rates of adverse radiation effect (6.4% vs. 2.0% at 1 year; multivariable hazard ratio [HR], 4.47; 95% confidence interval [CI], 1.57–12.73; P = 0.005), lower rates of extracranial failure (69.7% vs. 80.8% at 1 year; multivariable HR, 0.60; 95% CI, 0.42–0.87; P = 0.007), and better overall survival (48.6% vs. 25.4% at 1 year; multivariable HR, 0.57; 95% CI, 0.33–0.99; P = 0.044) compared with nonconcurrent therapy. SRS-ICI timing was not associated with local failure or distant intracranial failure. Conclusions Concurrent SRS-ICI therapy has a tolerable adverse event profile and may improve extracranial disease control and overall survival, supporting concurrent use in the management of BMs.

Introduction The CyberKnife, a frameless, robotic, stereotactic device, has been developed to radiosurgically treat arteriovenous malformations (AVMs). While most AVMs are obliterated within two-to-three years, a subset remain recalcitrant; long-term data on these difficult to treat AVMs are limited in the neurosurgical literature. Materials and methods A retrospective analysis of all patients who underwent CyberKnife treatment for intracranial AVMs at a single U.S. institution between 2002 and 2012, whose AVMs had failed to obliterate within 48 months or longer from the treatment start date, were eligible for inclusion. Results Eleven patients (9 AVMs; 7 males, 2 females) were followed for an average of 85.2 months (range 56.2–119.4). The median lesion size was 3.5 cm (range: 2.8–8.0 cm) and median Spetzler-Martin grade was 3 (range: 2–5). All AVMs were treated with one radiation dose (median prescribed dose was 18.0 Gy; median Dmax: 23.7 Gy). Six (66.7%) were obliterated in a median time of 84 months (range: 52–94 months), while 3 (33.3%) remained active after a median of 90.8 months (range 69.7–119.4). Transient, post-radiosurgery adverse radiation effects occurred in 5 (55.6%) cases. One (11.1%) patient had an acute hemorrhage from the AVM after radiosurgery. Four (44.4%) patients underwent repeat radiosurgery and/or embolization. Three of these lesions eventually obliterated, while 1 did not. Conclusion The median time to obliteration was 84 months. Two-thirds of AVMs which persisted for over 4 years following initial radiosurgery treatment eventually obliterated. Transient post-radiosurgery adverse effects were common; delayed hemorrhages were rare in our case series.

Introduction Since Lars Leksell developed the first stereotactic radiosurgery (SRS) device in 1951, there has been growth in the technologies available and clinical indications for SRS. This expansion has been reflected in the medical literature, which is built upon key articles and institutions that have significantly impacted SRS applications. Our aim was to identify these prominent works and provide an educational tool for training and further inquiry. Method A list of search phrases relating to central nervous system applications of stereotactic radiosurgery was compiled. A topic search was performed using PubMed and Scopus databases. The journal, year of publication, authors, treatment technology, clinical subject, study design and level of evidence for each article were documented. Influence was proposed by citation count and rate. Results Our search identified a total of 10,211 articles with the top 10 publications overall on the study of SRS spanning 443–1313 total citations. Four articles reported on randomized controlled trials, all of which evaluated intracranial metastases. The most prominent subtopics included SRS for arteriovenous malformation, glioblastoma, and acoustic neuroma. Greatest representation by treatment modality included Gamma Knife, LINAC, and TomoTherapy. Conclusions This systematic reporting of the influential literature on SRS for intracranial and spinal pathologies underscores the technology’s rapid and wide reaching clinical applications. Moreover the findings provide an academic guide to future health practitioners and engineers in their study of SRS for neurosurgery.

Background Stereotactic radiosurgery (SRS) for benign intracranial tumors is an established standard of care. The widespread implementation of SRS for benign spinal tumors has been limited by lack of long-term data. Objective To update our institutional experience of safety and efficacy outcomes after SRS for benign spinal tumors. Methods We performed a retrospective cohort study of 120 patients with 149 benign spinal tumors (39 meningiomas, 26 neurofibromas, and 84 schwannomas) treated with SRS between 1999 and 2016, with follow-up magnetic resonance imaging available for review. The primary endpoint was the cumulative incidence of local failure (LF), with death as a competing risk. Secondary endpoints included tumor shrinkage, symptom response, toxicity, and secondary malignancy. Results Median follow-up was 49 mo (interquartile range: 25-103 mo, range: 3-216 mo), including 61 courses with >5 yr and 24 courses with >10 yr of follow-up. We observed 9 LF for a cumulative incidence of LF of 2%, 5%, and 12% at 3, 5, and 10 yr, respectively. Excluding 10 tumors that were previously irradiated or that arose within a previously irradiated field, the 3-, 5-, and 10-yr cumulative incidence rates of LF were 1%, 2%, and 8%, respectively. At last follow-up, 35% of all lesions had decreased in size. With a total of 776 patient-years of follow-up, no SRS-related secondary malignancies were observed. Conclusion Comparable to SRS for benign intracranial tumors, SRS provides longer term local control of benign spinal tumors and is a standard-of-care alternative to surgical resection.

Purpose Foramen magnum meningiomas (FMMs) are a major surgical challenge, due to relevant surgical morbidity and mortality. The paper aims to review the clinical (symptomatic improvement, complication rate, length of hospital stay) and radiological outcome (completeness of resection) of microsurgical resection of FMMs, and to identify predictors of complications. Methods A multi-institutional retrospective review of prospectively maintained database of FMMs included 51 patients (74.5% females) with a median tumor volume of 8.18 cm3 (range, 1.77–57.9 cm3) and median follow-up of 36 months (range, 0.30–180.0 months). Tumors were resected though suboccipital approach (58.8%) or transcondylar approach (39.3%). Results Gross-total resection (GTR) was achieved in 80.4%, while local tumor control in 98% of cases. Clinical symptoms improved in 34 patients (66.7%) and worsened in 5 (9.8%). The median length of hospital stay was 5 days. Mortality was null. Postoperative complications developed in 15 patients (29.4%), with cerebrospinal fluid leak (7.8%) and lower cranial nerves deficits (7.8%) as the most frequent. Craniospinal location (p = 0.03), location anterior to the dentate ligament (DL) (p = 0.02), involvement of vertebral artery (VA) (p = 0.03) were significantly associated with complication rate. These three elements allow calculating the Foramen Magnum Meningioma Risk Score (FRMMRS), to estimate the risk of post-operative complications. Conclusion Microsurgical resection allows for high GTR rate and local tumor control rate, despite complications in one third of the patients. The FMMRS allows classifying FMMs and estimating the risk of post-operative complications.

Foramen magnum meningiomas (FMMs) are a major surgical challenge, due to relevant surgical morbidity and mortality. The paper aims to review the clinical (symptomatic improvement, complication rate, length of hospital stay) and radiological outcome (completeness of resection) of microsurgical resection of FMMs, and to identify predictors of complications.A multi-institutional retrospective review of prospectively maintained database of FMMs included 51 patients (74.5% females) with a median tumor volume of 8.18 cmGross-total resection (GTR) was achieved in 80.4% and 98% of cases did not present tumor regrowth or recurrence. Clinical symptoms improved in 34 patients (66.7%) and worsened in 5 (9.8%). The median length of hospital stay was 5 days. Mortality was null. Postoperative complications developed in 15 patients (29.4%), with cerebrospinal fluid leak (7.8%) and lower cranial nerves deficits (7.8%) as the most frequent. Craniospinal location (p = 0.03), location anterior to the dentate ligament (DL) (p = 0.02), involvement of vertebral artery (VA) (p = 0.03) were significantly associated with complication rate. These three elements allow calculating the Foramen Magnum Meningioma Risk Score (FRMMRS), to estimate the risk of post-operative complications.Microsurgical resection allows for high GTR rate and low rate of tumor regrowth or recurrence, despite complications in one third of the patients. The FMMRS allows classifying FMMs and estimating the risk of post-operative complications.

INTRODUCTION: Immune checkpoint inhibitors have become standard of care for many patients with non-small cell lung cancer (NSCLC). These agents often cause immune-related adverse events (IRAEs), which have been associated with increased overall survival (OS). Intracranial disease control and OS for patients experiencing IRAEs with metastatic NSCLC and brain metastases have not yet been described. METHODS: We performed a single-institution, retrospective review of patients with NSCLC and existing diagnosis of brain metastasis, who underwent pembrolizumab treatment and developed any grade IRAE. The primary outcome of the study was intracranial time to treatment failure (TTF), defined from time of pembrolizumab initiation to new intracranial disease progression or death. Kaplan-Meier and Cox proportional hazard analyses were performed. RESULTS: A total of 63 patients with NSCLC brain metastasis were identified, and 24 developed IRAEs. Patients with any grade IRAEs had longer OS (21 versus 10 months (p=0.004), systemic TTF (15 versus 4 months, p