Olson, Jeffrey J.

PURPOSE GBM AGILE (ClinicalTrials.gov identifier: NCT03970447 ) is a phase II/III Bayesian adaptive platform registration trial testing multiple arms against a common control; the primary end point is overall survival (OS). Regorafenib, a multikinase inhibitor, showed OS benefit in recurrent (RD) glioblastoma in the phase II REGOMA trial and entered GBM AGILE as the first investigational arm. METHODS Patient subtypes included in the regorafenib arm of GBM AGILE were newly diagnosed unmethylated (NDU) and RD glioblastoma. Prospective defined sets of subtypes, or arm signatures, were NDU, RD, and all (NDU + RD). As the first investigational arm in GBM AGILE, regorafenib was equally randomized to the control arm. Treatment in the control arm is temozolomide + radiotherapy (in newly diagnosed) or lomustine (in RD). Efficacy was assessed by OS hazard ratio (HR), arm/control, and demonstrated when the Bayesian probability of benefit (HR <1.00) was ≥98%. Analysis was performed monthly for limited efficacy, which occurs when the Bayesian predictive power is <25% for all signatures, and determines stopping enrollment. Follow-up continued for 12 months after accrual stopped. RESULTS When the predictive power was <25% in all predefined signatures for regorafenib, accrual stopped for limited efficacy. The final analysis did not demonstrate OS improvement in the regorafenib arm in RD nor NDU glioblastoma. Median HRs were 1.05 (NDU), 1.07 (RD), and 1.07 (all) with final probabilities of benefit (HR <1.00) of 0.421 (NDU), 0.312 (RD), and 0.296 (all). Regorafenib was associated with increased toxicity relative to control. CONCLUSION GBM AGILE did not show superiority of regorafenib over control in RD (lomustine) or NDU (temozolomide + radiotherapy) glioblastoma, yet caused increased toxicities. Regorafenib has been removed from National Comprehensive Cancer Network guidelines as a treatment option for RD.

BACKGROUND: Surgical intervention remains an important option in the management of vestibular schwannoma (VSs). Development of a systematic approach to choose the most appropriate route for this intervention, based on existing published evidence, is an important goal. OBJECTIVE: To review the literature published since the 2018 Congress of Neurological Surgeons Guideline on surgical intervention for patients with sporadic VSs and use this information to update that set of recommendations. METHODS: The literature in the PubMed and MEDLINE databases from January 2015 through May 20, 2022, was searched for manuscripts pertaining to surgical intervention for VSs. Those manuscripts meeting inclusion criteria were then analyzed for creation of recommendations in response to a set of updated questions. RESULTS: The resultant findings included a considerable amount of data that did not alter the recommendations form the 2018 publication on this topic. Thus, recommendations stating hearing preservation surgery through the middle fossa or retrosigmoid approach may be considered in individuals with good preoperative hearing as an alternative to simple observation remain. In addition, if microsurgical resection is necessary after stereotactic radiosurgery, it is recommended that patients be counseled that there is an increased likelihood of a subtotal resection and decreased facial nerve function. In some questions, insufficient data were present to create an answer and that is stated. CONCLUSION: This guideline demonstrates surgical intervention for VSs and represents a range of options, and the choice of the intervention depends on the specific aspects of the lesion and the individual that harbors them. Objective refinement of those choices will require thoughtful research design by investigations that wish to address those items for which we still have insufficient information. The full guideline can be seen online at https://www.cns.org/guidelines/treatment-adults-vestibular-schwannoma/7-surgical-resection-treatment-of-patients-with-ve-2

BACKGROUND: Given the increasing prevalence and shifting disease demographic of vestibular schwannoma toward smaller tumors in people with less advanced symptoms, increasing emphasis has been placed on functional hearing preservation. OBJECTIVE: To provide an update to the 2018 CNS Guideline on hearing preservation outcomes in patients with sporadic vestibular schwannoma. METHODS: Systematic review and clinical practice guideline summarizing data pertaining to hearing preservation outcomes within the first 10 years after contemporary stereotactic radiation, microsurgery, or observation with serial imaging. The analysis incorporates studies included in the 2018 guideline and additional literature published up to May 20, 2022, providing a comprehensive up-to-date review of published clinical outcome data over time. RESULTS: Pooled estimated rates of serviceable hearing preservation are presented for observation, radiosurgery, and microsurgery for adults with sporadic vestibular schwannoma who have documented serviceable hearing in the ipsilateral ear at the time of diagnosis. Overall estimated rates of maintaining serviceable hearing are 78% at 2 years, 59% at 5 years, and 47% at 10 years during observation; 71% at 2 years, 59% at 5 years, and 38% at 10 years after radiosurgery; and 48% at 2 years, 40% at 5 years, and 32% at 10 years after microsurgery. In addition, features portending hearing outcome among management modalities are reported to guide accurate patient counseling. CONCLUSION: Regardless of treatment modality, fewer than half of patients with sporadic vestibular schwannoma who present with serviceable hearing will maintain useful hearing by 10 years. Across all studies, microsurgery and radiosurgery seem to accelerate this decline over the natural history, although further research is needed given limitations of available evidence. The full guideline can be seen online at https://www.cns.org/guidelines/treatment-adults-vestibular-schwannoma/4-hearing-preservation-outcomes-in-patients-with-s

BACKGROUND: Intraoperative neuromonitoring (IONM) has become vital in the management of vestibular schwannoma (VS) with the paradigm shift from tumor eradication to functional preservation. Several facial nerve (FN) monitoring strategies have been explored over the past few decades ranging from free-running electromyography, direct nerve stimulation, continuous nerve stimulation, facial motor evoked potentials, blink reflex, and others. Hearing preservation surgery is guided primarily by far-field auditory brainstem response and real-time cochlear nerve action potentials. Given the heterogeneity in tumor and patient factors, it remains very difficult to accurately predict cranial nerve outcomes, regardless of the monitoring strategy. OBJECTIVE: To critically appraise literature regarding IONM during VS surgery and update the previous evidence-based clinical practice guideline. METHODS: This is a systematic review of the literature, incorporating articles from March 2015 to May 2022. Literature published before 2015 that would have been included in the previous Congress of Neurological Surgeons guideline was not searched again in this update. RESULTS: FN monitoring provides better functional outcomes compared with anatomic dissection alone and may guide the extent of tumor resection. While facial motor evoked potentials and free-running electromyography can provide continuous noninvasive FN monitoring, there are insufficient data to determine which more strongly correlates with facial function outcomes. Both electrophysiological data and tumor size correlate with facial function outcomes. The ideal hearing monitoring strategy remains unclear as there are insufficient data comparing cochlear nerve action potentials with far-field auditory brainstem response. All studies were graded as Class III evidence. CONCLUSION: IONM should be used in all VS cases. While the optimal FN and hearing monitoring strategy remains elusive, available data support the use of a combination of strategies, including preoperative tumor size, to maximize sensitivity and specificity. There remains a significant need for high-quality comparative studies to determine which intraoperative monitoring scheme can provide intraoperative guidance and predict postoperative outcome. The full guideline can be seen online at https://www.cns.org/guidelines/treatment-adults-vestibular-schwannoma/3-intraoperative-cranial-nerve-monitoring-in-manag

BACKGROUND: Stereotactic radiosurgery (SRS) is an established modality for treatment of adult patients with vestibular schwannomas (VS). The aim of this work was to provide an updated literature review on this topic. OBJECTIVE: To review the literature published since the last guideline on this topic. METHODS: OVID MEDLINE and Embase were searched for the period January 1, 2015, to May 20, 2022, using search terms and search strategies to identify pertinent abstracts. These were then screened using published exclusion/inclusion criteria to identify full-text review articles. Evidence tables were constructed using data derived from full-text reviews and recommendations made from the evidence derived. RESULTS: From the total 1035 abstracts identified, 26 full-text articles met inclusion/exclusion criteria and were included in this update. Four new level III recommendations stemmed from this work. In adult patients with sporadic intracanalicular or <2 cm VS, SRS should not be recommended as superior to observation alone for hearing preservation. In adult patients with sporadic VS treated with SRS, cochlear dose constraint should be considered because it provides better hearing preservation than no constraint. In the same population, single fraction SRS should be recommended rather than hypofractionated SRS (>1 and ≤5 fractions) because it results in decreased cranial nerve dysfunction. Finally, adult patients with sporadic VS undergoing SRS should be informed that SRS does not result in an increased number of secondary malignancies compared with the rate expected in the overall population. CONCLUSION: Recent published literature provides new recommendations for the treatment of adult patients with VS with SRS. The full guideline can be seen online at https://www.cns.org/guidelines/treatment-adults-vestibular-schwannoma/6-role-of-radiosurgery-srs-radiation-therapy-in-ma

Objective The objective of the current study was to present the results of an international working group survey identifying perceived limitations of existing facial nerve grading scales to inform the development of a novel grading scale for assessing early postoperative facial paralysis that incorporates regional scoring and is anchored in recovery prognosis and risk of associated complications. Study Design Survey. Setting A working group of 48 multidisciplinary clinicians with expertise in skull base, cerebellopontine angle, temporal bone, or parotid gland surgery. Results House-Brackmann grade is the most widely used system to assess facial nerve function among working group members (81%), although more than half (54%) agreed that the system they currently use does not adequately estimate the risk of associated complications, such as corneal injury, and confidence in interrater and intrarater reliability is generally low. Simplicity was ranked as the most important attribute of a novel postoperative facial nerve grading system to increase the likelihood of adoption, followed by reliability and accuracy. There was widespread consensus (91%) that the eye is the most critical facial region to focus on in the early postoperative setting. Conclusions Members were invited to submit proposed grading systems in alignment with the objectives of the working group for subsequent validation. From these data, we plan to develop a simple, clinically anchored, and reproducible staging system with regional scoring for assessing early postoperative facial nerve function after surgery of the skull base, cerebellopontine angle, temporal bone, or parotid gland.

Abstract The CD8 + T-cell response is prognostic for survival outcomes in several tumor types. However, whether this extends to tumors in the brain, an organ with barriers to T cell entry, remains unclear. Here, we analyzed immune infiltration in 67 brain metastasis (BrM) and found high frequencies of PD1 + TCF1 + stem-like CD8 + T-cells and TCF1- effector-like cells. Importantly, the stem-like cells aggregate with antigen presenting cells in immune niches, and niches were prognostic for local disease control. Standard of care for BrM is resection followed by stereotactic radiosurgery (SRS), so to determine SRS’s impact on the BrM immune response, we examined 76 BrM treated with pre-operative SRS (pSRS). pSRS acutely reduced CD8 + T cells at 3 days. However, CD8 + T cells rebounded by day 6, driven by increased frequency of effector-like cells. This suggests that the immune response in BrM can be regenerated rapidly, likely by the local TCF1 + stem-like population.

BACKGROUND: The Institute of Medicine best practice recommendation to review guidelines every 5 years is followed by the Congress of Neurological Surgeons Guidelines Committee. The aim of this work was to provide an updated literature review and evidence-based recommendations on the topic of diagnosis and treatment of patients with progressive glioblastoma (pGBM). OBJECTIVE: To review the literature published since the last guidelines on pGBM dated 2014, with literature search ending in June 2012. METHODS: PubMed, Embase, and Cochrane were searched for the period July 1, 2012, to March 31, 2019, using search terms and search strategies to identify pertinent abstracts. These were then screened using published exclusion/inclusion criteria to identify full-text review articles. Evidence tables were constructed using data derived from full-text reviews and recommendations made from the evidence derived. RESULTS: From the total 8786 abstracts identified by the search, 237 full-text articles met inclusion/exclusion criteria and were included in this update. Two new level II recommendations derived from this work. For the diagnosis of patients with GBM, the use of diffusion-weighted images is recommended to be included in the magnetic resonance images with and without contrast used for surveillance to detect pGBM. For the treatment of patients with pGBM, repeat cytoreductive surgery is recommended to improve overall survival. An additional 21 level III recommendations were provided. CONCLUSION: Recent published literature provides new recommendations for the diagnosis and treatment of pGBM. The Central Nervous System Guidelines Committee will continue to pursue timely updates to further improve the care of patients with diagnosis. https://www.cns.org/guidelines/browse-guidelines-detail/guidelines-management-of-progressive-glioblastoma

Abstract Background Stereotactic radiosurgery (SRS) is often the primary treatment modality for patients with intracranial metastatic disease. Despite advances in magnetic resonance imaging, including use of perfusion and diffusion sequences and molecular imaging, distinguishing radiation necrosis from progressive tumor remains a diagnostic and clinical challenge. We investigated the sensitivity and specificity of 18F-fluciclovine PET to accurately distinguish radiation necrosis from recurrent intracranial metastatic disease in patients who had previously undergone SRS. Methods Fluciclovine PET imaging was performed in 8 patients with a total of 15 lesions that had previously undergone SRS and had subsequent MRI and clinical features suspicious for recurrent disease. The SUVmax of each lesion and the contralateral normal brain parenchyma were summated and evaluated at 4 different time points (5 minutes, 10 minutes, 30 minutes, and 55 minutes). Lesions were characterized as either recurrent disease (11 of 15 lesions) or radiation necrosis (4 of 15 lesions) and confirmed with histopathological correlation (7 lesions) or through serial MRI studies (8 lesions). Results Time activity curve analysis found statistically greater radiotracer accumulation for all lesions, including radiation necrosis, when compared to contralateral normal brain. While the mean and median SUVmax for recurrent disease was statistically greater than that of radiation necrosis at all time points, the difference was more significant at the earlier time points (p = 0.004 at 5 min – 0.025 at 55 min). Using a SUVmax threshold of ≥1.3, fluciclovine PET demonstrated a 100% accuracy in distinguishing recurrent disease from radiation necrosis up to 30 minutes after injection and an accuracy of 87% (sensitivity = 0.91, specificity = 0.75) at the last time point of 55 minutes. However, tumor to brain ratios (TBRmax) were not significantly different between recurrent disease and radiation necrosis at any time point due to variable levels of fluciclovine uptake in the background brain parenchyma. Conclusions Fluciclovine PET may play an important role in distinguishing active intracranial metastatic lesions from radiation necrosis in patients previously treated with SRS but needs to be validated in larger studies.

Abstract Background Stereotactic radiosurgery (SRS) is often the primary treatment modality for patients with intracranial metastatic disease. Despite advances in magnetic resonance imaging, including use of perfusion and diffusion sequences and molecular imaging, distinguishing radiation necrosis from progressive tumor remains a diagnostic and clinical challenge. We investigated the sensitivity and specificity of 18F-fluciclovine PET to accurately distinguish radiation necrosis from recurrent intracranial metastatic disease in patients who had previously undergone SRS. Methods Fluciclovine PET imaging was performed in 8 patients with a total of 15 lesions that had previously undergone SRS and had subsequent MRI and clinical features suspicious for recurrent disease. The SUVmax of each lesion and the contralateral normal brain parenchyma were summated and evaluated at 4 different time points (5 minutes, 10 minutes, 30 minutes, and 55 minutes). Lesions were characterized as either recurrent disease (11 of 15 lesions) or radiation necrosis (4 of 15 lesions) and confirmed with histopathological correlation (7 lesions) or through serial MRI studies (8 lesions). Results Time activity curve analysis found statistically greater radiotracer accumulation for all lesions, including radiation necrosis, when compared to contralateral normal brain. While the mean and median SUVmax for recurrent disease was statistically greater than that of radiation necrosis at all time points, the difference was more significant at the earlier time points (p = 0.004 at 5 min – 0.025 at 55 min). Using a SUVmax threshold of ≥ 1.3, fluciclovine PET demonstrated a 100% accuracy in distinguishing recurrent disease from radiation necrosis up to 30 minutes after injection and an accuracy of 87% (sensitivity = 0.91, specificity = 0.75) at the last time point of 55 minutes. However, tumor to brain ratios (TBRmax) were not significantly different between recurrent disease and radiation necrosis at any time point due to variable levels of fluciclovine uptake in the background brain parenchyma. Conclusions Fluciclovine PET may play an important role in distinguishing active intracranial metastatic lesions from radiation necrosis in patients previously treated with SRS but needs to be validated in larger studies.