Brain metastases from renal cell carcinoma: Effects of novel systemic agents on brain metastasis outcomes

OBJECTIVE

The objective of this study was to examine survival outcomes in 136 patients with renal cell carcinoma with metastases to the brain who were treated with radiation combined with immunotherapy or tyrosine kinase inhibitor compared to those who were treated with radiation therapy alone.

METHODS

The Wake Forest Gamma Knife prospective database was searched for all patients with renal cell carcinoma brain metastases. Outcome measurements included overall survival, determined via the Kaplan-Meier Method, and cumulative incidence of local and distant failure, determined using the Fine Gray competing risks analysis with death as a competing risk for the 136 patients included.

RESULTS

Overall survival for the entire population at 6 months, 12 months, and 24 months was 67%, 47% and 30%, respectively. For the TKI (non-immunotherapy-treated) population (n = 37), overall survival was 75%, 61%, and 40% at 6 months, 12 months, and 24 months, respectively. For the immunotherapy-treated population (n = 35), overall survival was 85%, 64%, and 50% at 6 months, 12 months, and 24 months, respectively. Overall survival was significantly increased for patients who received radiation with either immunotherapy or TKI (p < 0.0001).

CONCLUSION

Prior series of patients with brain metastases of multiple histologies have demonstrated an improvement in the local efficacy of stereotactic radiosurgery when combined with systemic agents. We found that patients treated with targeted agents and patients treated with immunotherapy demonstrated a trend towards improvement over patients treated in the era prior to the advent of either classes of novel therapies.

Sub-second and multi-second dopamine dynamics underlie variability in human time perception

Timing behaviour and the perception of time are fundamental to cognitive and emotional processes in humans. In non-human model organisms, the neuromodulator dopamine has been associated with variations in timing behaviour, but the connection between variations in dopamine levels and the human experience of time has not been directly assessed. Here, we report how dopamine levels in human striatum, measured with sub-second temporal resolution during awake deep brain stimulation surgery, relate to participants' perceptual judgements of time intervals. Fast, phasic, dopaminergic signals were associated with underestimation of temporal intervals, whereas slower, tonic, decreases in dopamine were associated with poorer temporal precision. Our findings suggest a delicate and complex role for the dynamics and tone of dopaminergic signals in the conscious experience of time in humans.

Delayed Imaging Changes 18 Months or Longer After Stereotactic Radiosurgery for Brain Metastases: Necrosis or Progression

OBJECTIVE

Imaging changes after stereotactic radiosurgery (SRS) can occur for years after treatment, although the available data on the incidence of tumor progression and adverse radiation effects (ARE) are generally limited to the first 2 years after treatment.

METHODS

A single-institution retrospective review was conducted of patients who had >18 months of imaging follow-up available. Patients who had ≥1 metastatic brain lesions treated with Gamma Knife SRS were assessed for the time to radiographic progression. Those with progression ≥18 months after the initial treatment were included in the present study. The lesions that progressed were characterized as either ARE or tumor progression based on the tissue diagnosis or imaging characteristics over time.

RESULTS

The cumulative incidence of delayed imaging radiographic progression was 35% at 5 years after the initial SRS. The cumulative incidence curves of the time to radiographic progression for lesions determined to be ARE and lesions determined to be tumor progression were not significantly different statistically. The cumulative incidence of delayed ARE and delayed tumor progression was 17% and 16% at 5 years, respectively. Multivariate analysis indicated that the number of metastatic brain lesions present at the initial SRS was the only factor associated with late radiographic progression.

CONCLUSIONS

The timing of late radiographic progression does not differ between ARE and tumor progression. The number of metastatic brain lesions at the initial SRS is a risk factor for late radiographic progression.

Subsecond fluctuations in extracellular dopamine encode reward and punishment prediction errors in humans

In the mammalian brain, midbrain dopamine neuron activity is hypothesized to encode reward prediction errors that promote learning and guide behavior by causing rapid changes in dopamine levels in target brain regions. This hypothesis (and alternatives regarding dopamine's role in punishment-learning) has limited direct evidence in humans. We report intracranial, subsecond measurements of dopamine release in human striatum measured, while volunteers (i.e., patients undergoing deep brain stimulation surgery) performed a probabilistic reward and punishment learning choice task designed to test whether dopamine release encodes only reward prediction errors or whether dopamine release may also encode adaptive punishment learning signals. Results demonstrate that extracellular dopamine levels can encode both reward and punishment prediction errors within distinct time intervals via independent valence-specific pathways in the human brain.

Genomic Signature for Oligometastatic Disease in Non-Small Cell Lung Cancer Patients with Brain Metastases

PURPOSE/OBJECTIVE(S)

Biomarkers for oligometastatic disease remain elusive and few studies have attempted to correlate genomic data to the presence of true oligometastatic disease.

MATERIALS/METHODS

Patients with non-small cell lung cancer (NSCLC) and brain metastases were identified in our departmental database. Electronic medical records were used to identify patients for whom liquid biopsy-based comprehensive genomic profiling (Guardant Health) was available. Oligometastatic disease was defined as patients having ≤5 non-brain metastases without diffuse involvement of a single organ. Widespread disease was any spread beyond oligometastatic. Fisher's exact tests were used to identify mutations statistically associated (p<0.1) with either oligometastatic or widespread extracranial disease. A score of +1 was assigned for every mutation present associated with oligometastatic disease, and -1 was assigned for mutations associated with widespread disease. Scores were summed for each patient to create a risk score for the likelihood of oligometastatic disease, with scores subsequently correlated to the likelihood of having oligometastatic disease vs widespread disease. For oligometastatic patients, a competing risk analysis was done to assess for cumulative incidence of oligometastatic progression accounting for the potential competing risks of widespread progression of extracranial disease or death. Cox regression was used to determine the association between oligometastatic risk score and oligometastatic progression.

RESULTS

One hundred thirty patients met study criteria and were included in the analysis. 51 patients (39%) had oligometastatic disease. Genetic mutations included in the Guardant panel associated (p<0.1) with the presence of oligometastatic extracranial disease included ATM, JAK2, MAP2K2, and NTRK1; ARID1A and CCNE1 were associated with widespread disease. Patients with a positive, neutral and negative risk score for oligometastatic disease had a 78%, 41% and 11.5% likelihood of having oligometastatic disease, respectively (p<0.0001). Overall survival for patients with positive, neutral and negative risk scores for oligometastatic disease was 86% vs 82% vs 64% at 6 months (p = 0.2). The competing risk analysis found that the oligometastatic risk score was significantly associated with the likelihood of oligometastatic progression based on the Wald Chi-square test. Patients with positive, neutral and negative risk scores for oligometastatic disease had a cumulative incidence of oligometastatic progression of 77% vs 35% vs 33% at 6 months (p = 0.03 from competing risk model).

CONCLUSION

Elucidation of a genomic signature for oligometastatic disease derived from non-invasive liquid biopsy appears feasible for NSCLC patients. Patients with the oligometastatic signature exhibited higher rates of early oligometastatic progression. Validation of this signature could lead to a biomarker that has the potential to direct local therapies in oligometastatic patients.

Sub-second Dopamine Signals during Risky Decision-Making in Patients with Impulse Control Disorder

Background

Impulse Control Disorder (ICD) in Parkinson's disease is a behavioral addiction arising secondary to dopaminergic therapies, most often dopamine receptor agonists. Prior research implicates changes in striatal function and heightened dopaminergic activity in the dorsal striatum of patients with ICD. However, this prior work does not possess the temporal resolution required to investigate dopaminergic signaling during real-time progression through various stages of decision-making involving anticipation and feedback.

Methods

We recorded high-frequency (10Hz) measurements of extracellular dopamine in the striatum of patients with (N=3) and without (N=3) a history of ICD secondary to dopamine receptor agonist therapy for Parkinson's disease symptoms. These measurements were made using carbon fiber microelectrodes during awake DBS neurosurgery and while participants performed a sequential decision-making task involving risky investment decisions and real monetary gains and losses. Per clinical standard-of-care, participants withheld all dopaminergic medications prior to the procedure.

Results

Patients with ICD invested significantly more money than patients without ICD. On each trial, patients with ICD made smaller adjustments to their investment levels compared to patients without ICD. In patients with ICD, dopamine levels rose or fell on sub-second timescales in anticipation of investment outcomes consistent with increased or decreased confidence in a positive outcome, respectively; dopamine levels in patients without ICD were significantly more stable during this phase. After outcome revelation, dopamine levels in patients with ICD rose significantly more than in inpatients without ICD for better-than-expected gains. For worse-than-expected losses, dopamine levels in patients with ICD remained level whereas dopamine levels in patients without ICD fell.

Conclusion

We report significantly increased risky behavior and exacerbated phasic dopamine signaling, on sub-second timescales, anticipating and following the revelation of the outcomes of risky decisions in patients with ICD. Notably, these results were obtained when patients who had demonstrated ICD in the past but were, at the time of surgery, in an off-medication state. Thus, it is unclear whether observed signals reflect an inherent predisposition for ICD that was revealed when dopamine receptor agonists were introduced or whether these observations were caused by the introduction of dopamine receptor agonists and the patients having experienced ICD symptoms in the past. Regardless, future work investigating dopamine's role in human cognition, behavior, and disease should consider the signals this system generates on sub-second timescales.

Intracranial subsecond dopamine measurements during a "sure bet or gamble" decision-making task in patients with alcohol use disorder suggest diminished dopaminergic signals about relief

OBJECTIVE

To the authors' knowledge, no data have been reported on dopamine fluctuations on subsecond timescales in humans with alcohol use disorder (AUD). In this study, dopamine release was monitored in 2 patients with and 2 without a history of AUD during a "sure bet or gamble" (SBORG) decision-making task to begin to characterize how subsecond dopamine responses to counterfactual information, related to psychological notions of regret and relief, in AUD may be altered.

METHODS

Measurements of extracellular dopamine levels were made once every 100 msec using human voltammetric methods. Measurements were made in the caudate during deep brain stimulation electrode implantation surgeries (for treatment of movement disorders) in patients who did (AUD, n = 2) or did not (non-AUD, n = 2) have a history of AUD. Participants performed an SBORG decision-making task in which they made choices between sure bets and 50%-chance monetary gamble outcomes.

RESULTS

Fast changes were found in dopamine levels that appear to be modulated by "what could have been" and by patients' AUD status. Positive counterfactual prediction errors (related to relief) differentiated patients with versus without a history of AUD.

CONCLUSIONS

Dopaminergic encoding of counterfactual information appears to differ between patients with and without AUD. The current study has a major limitation of a limited sample size, but these data provide a rare insight into dopaminergic physiology during real-time decision-making in humans with an addiction disorder. The authors hope future work will expand the sample size and determine the generalizability of the current results.

Five-Year Survivors from Brain Metastases Treated with Stereotactic Radiosurgery: Biology, Improving Treatments or Just Plain Luck?

Background

Improvements in therapies have led to an increasing number of long-term survivors of brain metastases. The present series compares a population of five-year survivors of brain metastases to a generalized brain metastases population to assess for factors attributable to long-term survival.

Methods

A single institution retrospective review was performed to identify five-year survivors of brain metastases who received stereotactic radiosurgery (SRS). A historical control population of 737 patients with brain metastases was used to assess similarities and differences between the long-term survivor population and the general population treated with SRS.

Results

98 patients with brain metastases were found to have survived over 60 months. No differences between long term survivors and controls were identified with regards to age at first SRS (P=0.19), primary cancer distribution (P=0.80), and number of metastases at first SRS (P=0.90). Cumulative incidence of neurologic death at six, eight and ten years for the long-term survivor cohort was 4.8%, 16%, and 16% respectively. In the historical controls, cumulative incidence of neurologic death reached a plateau at 40% after 4.9 years. A significant difference in the distribution of burden of disease at the time of first SRS was found between the five-year survivors and the control (P=0.0049). 58% of five-year survivors showed no evidence of clinical disease at the last follow-up.

Conclusion

Five-year survivors of brain metastases represent a diverse histologic population, suggesting a small population of oligometastatic and indolent cancers exist for each cancer type.

Immersion bioprinting of hyaluronan and collagen bioink-supported 3D patient-derived brain tumor organoids

Organoids, and in particular patient-derived organoids, have emerged as crucial tools for cancer research. Our organoid platform, which has supported patient-derived tumor organoids (PTOs) from a variety of tumor types, has been based on the use of hyaluronic acid (HA) and collagen, or gelatin, hydrogel bioinks. One hurdle to high throughput PTO biofabrication is that as high-throughput multi-well plates, bioprinted volumes have increased risk of contacting the sides of wells. When this happens, surface tension causes bioinks to fall flat, resulting in 2D cultures. To address this problem, we developed an organoid immersion bioprinting method-inspired by the FRESH printing method-in which organoids are bioprinted into support baths in well plates. The bath-in this case an HA solution-shields organoids from the well walls, preventing deformation. Here we describe an improvement to our approach, based on rheological assessment of previous gelatin baths versus newer HA support baths, combined with morphological assessment of immersion bioprinted organoids. HA print baths enabled more consistent organoid volumes and geometries. We optimized the printing parameters of this approach using a cell line. Finally, we deployed our optimized immersion bioprinting approach into a drug screening application, using PTOs derived from glioma biospecimens, and a lung adenocarcinoma brain metastasis. In these studies, we showed a general dose dependent response to an experimental p53 activator compound and temozolomide (TMZ), the drug most commonly given to brain tumor patients. Responses to the p53 activator compound were effective across all PTO sets, while TMZ responses were observed, but less pronounced, potentially explained by genetic and epigenetic states of the originating tumors. The studies presented herein showcase a bioprinting methodology that we hope can be used in increased throughput settings to help automate biofabrication of PTOs for drug development-based screening studies and precision medicine applications.

Intensity-modulated radiotherapy with planned Gamma Knife radiosurgery boost for head and neck cancer with extensive disease in proximity to critical structures

BACKGROUND

To describe intensity-modulated radiotherapy (IMRT) with Gamma Knife Radiosurgery (GKRS) boost for locally advanced head and neck cancer (HNC) with disease near dose-limiting structures.

METHODS

Patients with HNC treated with IMRT/GKRS as part of a combined modality approach between 2011 and 2021 were reviewed. Local control, overall survival and disease-specific survival were estimated using the Kaplan Meier method.

RESULTS

Twenty patients were included. Nineteen patients had T3-4 tumors. Median follow-up was 26.3 months. GKRS site control was 95%. Two patients progressed at the treated primary site, one patient failed at the edge of the GKRS treatment volume, with no perineural or intracranial failure. 2-year OS was 94.7% (95% CI: 85.2%-100%). Concurrent chemotherapy was given in nine patients (45%). One patient (5%) received induction/concurrent chemotherapy. Brain radionecrosis occurred in three patients, one of which was biopsy-proven.

CONCLUSIONS

IMRT plus GKRS boost results in excellent disease control near critical structures with minimal toxicity.

A transformer-based deep-learning approach for classifying brain metastases into primary organ sites using clinical whole-brain MRI images

Treatment decisions for brain metastatic disease rely on knowledge of the primary organ site and are currently made with biopsy and histology. Here, we develop a deep-learning approach for accurate non-invasive digital histology with whole-brain magnetic resonance imaging (MRI) data. Contrast-enhanced T1-weighted and fast spoiled gradient echo brain MRI exams (n = 1,582) were preprocessed and input to the proposed deep-learning workflow for tumor segmentation, modality transfer, and primary site classification into one of five classes. Tenfold cross-validation generated an overall area under the receiver operating characteristic curve (AUC) of 0.878 (95% confidence interval [CI]: 0.873,0.883). These data establish that whole-brain imaging features are discriminative enough to allow accurate diagnosis of the primary organ site of malignancy. Our end-to-end deep radiomic approach has great potential for classifying metastatic tumor types from whole-brain MRI images. Further refinement may offer an invaluable clinical tool to expedite primary cancer site identification for precision treatment and improved outcomes.

Clinical Outcomes of Dose Escalated Re-Irradiation in Patients with Recurrent High Grade Glioma

Background

Reirradiation for recurrent gliomas is a controversial treatment option with no clear standard dose or concurrent systemic therapy.

Methods

This series represents a single institution retrospective review of patients treated with re-irradiation for recurrent high grade glioma. After 2012, patients were commonly offered concurrent bevacizumab as a cytoprotective agent against radiation necrosis. Kaplan Meier method was used to estimate overall and progression-free survival. Cox proportional hazards regression was used to identify factors associated with overall and progression-free survival.

Results

Between 2001 and 2021, 52 patients underwent re-irradiation for a diagnosis of recurrent high grade glioma. 36 patients (69.2%) had a histologic diagnosis of glioblastoma at time of re-irradiation. The median BED10 (biologic equivalent dose 10 Gy) of re-irradiation was 53.1 Gy . Twenty-one patients (40.4%) received concurrent bevacizumab with re-irradiation. Median survival for the entire cohort and for glioblastoma at time of recurrence patients was 6.7 months and 6.0 months , respectively. For patients with glioblastoma at time of recurrence, completing re-irradiation (HR 0.03, p &lt; 0.001), use of concurrent bevacizumab (HR 0.3, p=0.009), and the BED10 (HR 0.9, p=0.005) were predictive of overall survival. Nine patients developed Grade 3-5 toxicity; of these, 2 received concurrent bevacizumab and 7 did not (p=0.15).

Conclusion

High dose re-irradiation with concurrent bevacizumab is feasible in patients with recurrent gliomas. Concurrent bevacizumab and increasing radiation dose may improve survival in recurrent glioblastoma patients.

Efficacy of Laser Interstitial Thermal Therapy (LITT) for Newly Diagnosed and Recurrent IDH Wild-type Glioblastoma

Background

Treatment options for unresectable new and recurrent glioblastoma remain limited. Laser ablation has demonstrated safety as a surgical approach to treat primary brain tumors. The LAANTERN prospective multicenter registry (NCT02392078) data was analyzed to determine clinical outcomes for patients with new and recurrent IDH wild-type glioblastoma.

Methods

Demographics, intraprocedural data, adverse events, KPS, health-economics, and survival data were prospectively collected then analyzed on IDH wild-type newly diagnosed and recurrent glioblastoma patients who were treated with laser ablation at 14 US centers between January 2016 and May 2019. Data was monitored for accuracy. Statistical analysis included individual variable summaries, multivariable differences in survival, and median survival numbers.

Results

A total of 29 new and 60 recurrent IDH wild-type WHO grade 4 glioblastoma patients were treated. Positive MGMT promoter methylation status was present in 5/29 of new and 23/60 of recurrent patients. Median physician-estimated extent of ablation was 91-99%. Median overall-survival was 9.73 months (95% confidence interval: 5.16, 15.91) for newly diagnosed patients and median post-procedure survival was 8.97 (6.94, 12.36) months for recurrent patients. Median overall-survival for newly diagnosed patients receiving post-LITT chemo/radiation was 16.14 months (6.11, not reached). Factors associated with improved survival were MGMT promoter methylation, adjuvant chemotherapy within 12 weeks, and tumor volume &lt;3cc.

Conclusions

Laser ablation is a viable option for patients with new and recurrent glioblastoma. Median overall survival for IDH wild type newly diagnosed glioblastoma is comparable to outcomes observed in other tumor resection studies when those patients undergo radiation and chemotherapy following LITT.

Local control outcomes for combination of stereotactic radiosurgery and immunotherapy for non-small cell lung cancer brain metastases

BACKGROUND

Previous series have demonstrated CNS activity for immune checkpoint inhibitors, yet no prior data exists regarding whether this activity can improve outcomes of stereotactic radiosurgery.

METHODS

In this single institution retrospective series, the clinical outcomes of 80 consecutive lung cancer patients treated with concurrent immune checkpoint inhibitors and stereotactic radiosurgery were compared to 235 in the historical control cohort in which patients were treated prior to immune checkpoint inhibition being standard upfront therapy. Overall survival was estimated using the Kaplan Meier method. Cumulative incidence of local progression was estimated using a competing risk model.

RESULTS

Median overall survival time was improved in patients receiving upfront immunotherapy compared to the historical control group (40 months vs 8 months, p < 0.001). Factors affected overall survival include concurrent immunotherapy (HR 0.23, p < 0.0001) and KPS (HR 0.97, p = 0.0001). Cumulative incidence of local failure in the historical control group was 10% at 1 year, compared to 1.1% at 1 year in the concurrent immunotherapy group (p = 0.025). Factors affected local control included use of concurrent immunotherapy (HR 0.09, p = 0.012), and lowest margin dose delivered to a metastasis (HR 0.8, p = 0.0018).

CONCLUSION

Local control and overall survival were both improved in patients receiving concurrent immune checkpoint inhibitors with radiosurgery compared to historical controls. While these data remain to be validated, they suggest that brain metastasis patients may benefit from concurrent use of immunotherapy with SRS.

Upfront immunotherapy leads to lower brain metastasis velocity in patients undergoing stereotactic radiosurgery for brain metastases

Background

While immunotherapy has been shown to improve survival and decrease neurologic death in patients with brain metastases, it remains unclear whether this improvement is due to prevention of new metastasis to the brain.

Method

We performed a retrospective review of patients presenting with brain metastases simultaneously with the first diagnosis of metastatic disease and were treated with upfront immunotherapy as part of their treatment regimen and stereotactic radiosurgery (SRS) to the brain metastases. We compared this cohort with a historical control population (prior to the immunotherapy era) who were treated with pre-immunotherapy standard of care systemic therapy and with SRS to the brain metastases.

Results

Median overall survival time was improved in the patients receiving upfront immunotherapy compared to the historical cohort (48 months vs 8.4 months, p=0.001). Median time to distant brain failure was statistically equivalent (p=0.3) between the upfront immunotherapy cohort and historical control cohort (10.3 vs 12.6 months). Brain metastasis velocity was lower in the upfront immunotherapy cohort (median 3.72 metastases per year) than in the historical controls (median 9.48 metastases per year, p=0.001). Cumulative incidence of neurologic death at one year was 12% in the upfront immunotherapy cohort and 28% in the historical control cohort (p=0.1).

Conclusions

Upfront immunotherapy appears to improve overall survival and decrease BMV compared to historical controls. While these data remain to be validated, they suggest that brain metastasis patients may benefit from concurrent immunotherapy with SRS.

A Single-Institution Retrospective Study of Patients Treated With Laser-Interstitial Thermal Therapy for Radiation Necrosis of the Brain

Object

Laser-interstitial thermal therapy (LITT) has been proposed as an alternative treatment to surgery for radiation necrosis (RN) in patients treated with stereotactic radiosurgery (SRS) for brain metastases. The present study sought to retrospectively analyze LITT outcomes in patients with RN from SRS.

Methods

This was a single-institution retrospective study of 30 patients treated from 2011-2018 with pathologically-proven RN after SRS for brain metastases (n=28) or proximally treated extracranial lesions treated with external beam radiotherapy (n=2). Same-day biopsy was performed in all cases. Patients were prospectively followed with Functional Assessment of Cancer Therapy - Brain (FACT-Br), EuroQol-5 Dimension (EQ-5D), Hopkins Verbal Learning Test (HVLT) and clinical history and examination. Adjusted means, standard errors and tests comparing visits to pre-LITT were generated. Kaplan-Meier method was used to estimate time overall survival. Competing risk analysis was used to estimate cumulative incidence of LITT failure.

Results

In our patient population, median time from radiotherapy to LITT was 13.1 months. Median SRS dose and median LITT treatment target volume were 20 Gy (IQR 18-22) and 3.5 cc (IQR 2.2-4.6), respectively. Seventy-seven percent of our patients tapered off steroids within one month. There were only two instances of RN recurrence after LITT, with recurrence defined as recurrence of symptoms after initial improvement. These recurrences occurred at 1.9 and 3.4 months. The three-, six- and nine-month freedom from recurrence rates were 95.7%, 90.9%, and 90.9%. Median survival in our patient population with pathologically confirmed RN treated with LITT was 2.1 years. Regarding the quality of life questionnaires with which some patients were followed as part of different prospective studies, completion rates were 22/30 for FACT-Br, 16/30 for the EQ-5D and 8/30 for HVLT. Quality of life questionnaire results were overall stable from baseline. Mean FACT-Br scores were stable from baseline (17.9, 16.6, 21.4 and 22.8) to three months (18.8, 15.4, 18.4 and 23.4) (p=0.38, 0.53, 0.09 and 0.59). The mean EQ-5D Aggregate score was stable from baseline (7.1) to one month (7.6) (p=0.25). Mean HVLT-R Total Recall was stable from baseline (20.6) to three months (18.4) (p=0.09). There was a statistically significant decrease in mean Karnofsky Performance Scale (KPS) score from baseline (84) to three-month follow-up (75) (p=0.03).

Conclusions

LITT represents a safe and durably effective treatment option for RN in the brain. Results demonstrate a median survival of 2.1 years from LITT with only two recurrences, both within four months of treatment and salvageable. Patient-reported outcomes showed no severe declines after LITT. Quality of life questionnaires demonstrated stable well-being and functionality from baseline. LITT should be considered for definitive treatment of RN, especially in cases where patients have significant side effects from standards medical therapies such as steroids or if steroids are minimally effective. 

Phase I trial of convection-enhanced delivery of IL13RA2 and EPHA2 receptor targeted cytotoxins in dogs with spontaneous intracranial gliomas

Background

The interleukin-13 receptor alpha 2 (IL13RA2) and ephrin type A receptor 2 (EPHA2) are attractive therapeutic targets, being expressed in ~90% of canine and human gliomas, and absent in normal brain. Clinical trials using an earlier generation IL-13 based cytotoxin showed encouraging clinical effects in human glioma, but met with technical barriers associated with the convection-enhanced delivery (CED) method. In this study, IL-13 mutant and ephrin A1 (EFNA1)–based bacterial cytotoxins targeted to IL13RA2 and EPHA2 receptors, respectively, were administered locoregionally by CED to dogs with intracranial gliomas to evaluate their safety and preliminary efficacy.

Methods

In this phase I, 3 + 3 dose escalation trial, cytotoxins were infused by CED in 17 dogs with gliomas expressing IL13RA2 or EPHA2 receptors. CED was performed using a shape-fitting therapeutic planning algorithm, reflux-preventing catheters, and real-time intraoperative MRI monitoring. The primary endpoint was to determine the maximum tolerated dose of the cytotoxic cocktail in dogs with gliomas.

Results

Consistent intratumoral delivery of the cytotoxic cocktail was achieved, with a median target coverage of 70% (range, 40–94%). Cytotoxins were well tolerated over a dose range of 0.012–1.278 μg/mL delivered to the target volume (median, 0.099 μg/mL), with no dose limiting toxicities observed. Objective tumor responses, up to 94% tumor volume reduction, were observed in 50% (8/16) of dogs, including at least one dog in each dosing cohort >0.05 μg/mL.

Conclusions

This study provides preclinical data fundamental to the translation of this multireceptor targeted therapeutic approach to the human clinic.

Multi-Omics Analysis of Brain Metastasis Outcomes Following Craniotomy

Background

The incidence of brain metastasis continues to increase as therapeutic strategies have improved for a number of solid tumors. The presence of brain metastasis is associated with worse prognosis but it is unclear if distinctive biomarkers can separate patients at risk for CNS related death.

Methods

We executed a single institution retrospective collection of brain metastasis from patients who were diagnosed with lung, breast, and other primary tumors. The brain metastatic samples were sent for RNA sequencing, proteomic and metabolomic analysis of brain metastasis. The primary outcome was distant brain failure after definitive therapies that included craniotomy resection and radiation to surgical bed. Novel prognostic subtypes were discovered using transcriptomic data and sparse non-negative matrix factorization.

Results

We discovered two molecular subtypes showing statistically significant differential prognosis irrespective of tumor subtype. The median survival time of the good and the poor prognostic subtypes were 7.89 and 42.27 months, respectively. Further integrated characterization and analysis of these two distinctive prognostic subtypes using transcriptomic, proteomic, and metabolomic molecular profiles of patients identified key pathways and metabolites. The analysis suggested that immune microenvironment landscape as well as proliferation and migration signaling pathways may be responsible to the observed survival difference.

Conclusion

A multi-omics approach to characterization of brain metastasis provides an opportunity to identify clinically impactful biomarkers and associated prognostic subtypes and generate provocative integrative understanding of disease.

The Original Cushing Society: A Historical Review of the Senior Society's First 6 Meetings

The Society of Neurological Surgeons (SNS), founded in 1920, is one of the oldest neurosurgical society in the world. The founding members were prominent surgeons that met with the idea of furthering the field of neurosurgery. Initial meetings were forums to observe and discuss new surgeries. During the first 6 meetings of the SNS, surgical cases from the areas of cranial trauma, epilepsy, spinal cord tumors, brain tumors, pituitary tumor, trigeminal neuralgia, and cerebellar tumors were discussed. Publications from the members during that time included articles on the use of intracranial hypertonic saline, trigeminal neuralgia, brachial plexus injuries, management of head injury, spinal cord tumors, cervical spine trauma, and intracranial hemorrhage in the newborn. The members also invited lecturers from other specialties, such as neurology, ophthalmology, radiology, and pathology, typifying the interdisciplinary nature of neurosurgical practice. The meetings served as a forum to build consensus on neurosurgical treatment methods. Cases that ultimately changed the practice of neurosurgery at that time will be profiled. The SNS began as a traveling club of neurosurgical leaders who learned from each other's clinical experience to mold this burgeoning new field. However, the members made an impact on how neurosurgery was practiced nationally.

Laser Ablation of Abnormal Neurological Tissue Using Robotic Neuroblate System (LAANTERN): Procedural Safety and Hospitalization

BACKGROUND

Stereotactic laser ablation (SLA) has demonstrated potential utility for a spectrum of difficult to treat neurosurgical pathologies in multiple small and/or retrospective single-institutional series. Here, we present the safety profile of SLA of intracranial lesions from the Laser Ablation of Abnormal Neurological Tissue using Robotic NeuroBlate System (LAANTERN; Monteris Medical) multi-institutional, international prospective observational registry.

OBJECTIVE

To determine the procedural safety of SLA for intracranial lesions.

METHODS

Prospective procedural safety and hospitalization data from the first 100 treated LAANTERN patients was collected and analyzed.

RESULTS

Mean age and baseline Karnofsky Performance Status (KPS) were 51(± 17) yr and 83(± 15), respectively. In total, 81.2% of patients had undergone prior surgical or radiation treatment. Most patients had a single lesion (79%) ablated through 1 burr hole (1.2 ± 0.7 per patient), immediately following a lesion biopsy. In total, >90% of the lesion was ablated in 72% of treated lesions. Average total procedural time was 188.2 ± 69.6 min, and average blood loss was 17.7 ± 55.6 ccs. The average length of intensive care unit (ICU) and hospital stays before discharge were 38.1 ± 62.7 h and 61.1 ± 87.2 h, respectively. There were 5 adverse events (AEs) attributable to SLA (5/100; 5%). After the procedure, 84.8% of patients were discharged home. There was 1 mortality within 30 d of the procedure (1/100; 1%), which was not attributable to SLA.

CONCLUSION

SLA is a safe, minimally invasive procedure with favorable postprocedural ICU and hospital utilization profiles.

Sub-second Dopamine and Serotonin Signaling in Human Striatum during Perceptual Decision-Making

Recent animal research indicates that dopamine and serotonin, neuromodulators traditionally linked to appetitive and aversive processes, are also involved in sensory inference and decisions based on such inference. We tested this hypothesis in humans by monitoring sub-second striatal dopamine and serotonin signaling during a visual motion discrimination task that separates sensory uncertainty from decision difficulty in a factorial design. Caudate nucleus recordings (n = 4) revealed multi-scale encoding: in three participants, serotonin tracked sensory uncertainty, and, in one participant, both dopamine and serotonin tracked deviations from expected trial transitions within our factorial design. Putamen recordings (n = 1) supported a cognition-action separation between caudate nucleus and putamen—a striatal sub-division unique to primates—with both dopamine and serotonin tracking decision times. These first-of-their-kind observations in the human brain reveal a role for sub-second dopamine and serotonin signaling in non-reward-based aspects of cognition and action.

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Dopamine and serotonin are measured in human striatum during awake decision-making

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Serotonin tracks sensory uncertainty in caudate nucleus

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Dopamine and serotonin track sensory statistics in caudate nucleus

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Dopamine and serotonin track decision times in putamen

Attenuating hypoxia driven malignant behavior in glioblastoma with a novel hypoxia-inducible factor 2 alpha inhibitor

Hypoxia inducible factor (HIFs) signaling contributes to malignant cell behavior in glioblastoma (GBM). We investigated a novel HIF2α inhibitor, PT2385, both in vitro, with low-passage patient-derived cell lines, and in vivo, using orthotopic models of glioblastoma. We focused on analysis of HIF2α expression in situ, cell survival/proliferation, and survival in brain tumor-bearing mice treated with PT2385 alone and in combination with standard of care chemoradiotherapy. HIF2α expression increased with glioma grade, with over half of GBM specimens HIF2α positive. Staining clustered in perivascular and perinecrotic tumor regions. Cellular phenotype including proliferation, viability, migration/invasion, and also gene expression were not altered after PT2385 treatment. In the animal model, PT2385 single-agent treatment did improve median overall survival compared to placebo (p = 0.04, n = 21) without a bioluminescence correlate (t = 0.67, p = 0.52). No difference in animal survival was seen in combination treatment with radiation (RT)/temozolomide (TMZ)/PT2385 (p = 0.44, n = 10) or mean tumor bioluminescence (t 1.13, p = 0.32). We conclude that HIF2α is a reasonable novel therapeutic target as expressed in the majority of glioblastomas in our cohort. PT2385 as a single-agent was efficacious in vivo, however, an increase in animal survival was not seen with PT2385 in combination with RT/TMZ. Further study for targeting HIF2α as a therapeutic approach in GBM is warranted.

An envelope of linear and rotational head motion during everyday activities

Various studies have characterized head kinematics in specific everyday activities by looking at linear and/or rotational acceleration characteristics, but each has evaluated a limited number of activities. Furthermore, these studies often present dissimilar and sometimes incomplete descriptions of the resulting kinematics, so the characteristics of normal everyday activities as a whole are not easily collectively summarized. The purpose of this study was to evaluate the literature investigating head kinematics associated with everyday activities and to generate a comprehensive kinematic boundary envelope describing these motions. The envelope constructed constitutes the current state of published knowledge regarding 'normally occurring' head accelerations. The envelope of kinematics represents activities commonly encountered and posing zero to minimal risk of injury to healthy individuals. Several kinematic measures, including linear accelerations, rotational velocities, and rotational accelerations, one may encounter as a result of normal everyday activities are summarized. A total of 11 studies encompassing 49 unique activities were evaluated. Examples of activities include sitting in a chair, jumping off a step, running, and walking. The peak resultant linear accelerations of the head reported in the literature were all less than 15 g, while the peak resultant rotational accelerations and rotational velocities approach 1375 rad/s2 and 12.8 rad/s, respectively. The resulting design envelope can be used to understand the range of acceleration magnitudes a typical active person can expect to experience. The results are also useful to compare to other activities exposing the head to motion or impact including sports, military, automotive, aerospace and other sub-injurious and injurious events.

Subthalamic nucleus deep brain stimulation with a multiple independent constant current-controlled device in Parkinson's disease (INTREPID): a multicentre, double-blind, randomised, sham-controlled study

BACKGROUND

Deep brain stimulation (DBS) of the subthalamic nucleus is an established therapeutic option for managing motor symptoms of Parkinson's disease. We conducted a double-blind, sham-controlled, randomised controlled trial to assess subthalamic nucleus DBS, with a novel multiple independent contact current-controlled (MICC) device, in patients with Parkinson's disease.

METHODS

This trial took place at 23 implanting centres in the USA. Key inclusion criteria were age between 22 and 75 years, a diagnosis of idiopathic Parkinson's disease with over 5 years of motor symptoms, and stable use of anti-parkinsonian medications for 28 days before consent. Patients who passed screening criteria were implanted with the DBS device bilaterally in the subthalamic nucleus. Patients were randomly assigned in a 3:1 ratio to receive either active therapeutic stimulation settings (active group) or subtherapeutic stimulation settings (control group) for the 3-month blinded period. Randomisation took place with a computer-generated data capture system using a pre-generated randomisation table, stratified by site with random permuted blocks. During the 3-month blinded period, both patients and the assessors were masked to the treatment group while the unmasked programmer was responsible for programming and optimisation of device settings. The primary outcome was the difference in mean change from baseline visit to 3 months post-randomisation between the active and control groups in the mean number of waking hours per day with good symptom control and no troublesome dyskinesias, with no increase in anti-parkinsonian medications. Upon completion of the blinded phase, all patients received active treatment in the open-label period for up to 5 years. Primary and secondary outcomes were analysed by intention to treat. All patients who provided informed consent were included in the safety analysis. The open-label phase is ongoing with no new enrolment, and current findings are based on the prespecified interim analysis of the first 160 randomly assigned patients. The study is registered with ClinicalTrials.gov, NCT01839396.

FINDINGS

Between May 17, 2013, and Nov 30, 2017, 313 patients were enrolled across 23 sites. Of these 313 patients, 196 (63%) received the DBS implant and 191 (61%) were randomly assigned. Of the 160 patients included in the interim analysis, 121 (76%) were randomly assigned to the active group and 39 (24%) to the control group. The difference in mean change from the baseline visit (post-implant) to 3 months post-randomisation in increased ON time without troublesome dyskinesias between the active and control groups was 3·03 h (SD 4·52, 95% CI 1·3-4·7; p<0·0001). 26 serious adverse events in 20 (13%) patients occurred during the 3-month blinded period. Of these, 18 events were reported in the active group and 8 in the control group. One death was reported among the 196 patients before randomisation, which was unrelated to the procedure, device, or stimulation.

INTERPRETATION

This double-blind, sham-controlled, randomised controlled trial provides class I evidence of the safety and clinical efficacy of subthalamic nucleus DBS with a novel MICC device for the treatment of motor symptoms of Parkinson's disease. Future trials are needed to investigate potential benefits of producing a more defined current field using MICC technology, and its effect on clinical outcomes.

FUNDING

Boston Scientific.

Results of a third Gamma Knife radiosurgery for trigeminal neuralgia

OBJECTIVE

Gamma Knife radiosurgery (GKRS) is a commonly used procedure for medically refractory trigeminal neuralgia (TN), with repeat GKRS routinely done in cases of pain relapse. The results of a third GKRS in cases of further pain relapse have not been well described. In this study, the authors report the largest series of patients treated with a third GKRS for TN to date.

METHODS

Retrospective review of institutional electronic medical records and a GKRS database was performed to identify patients who had been treated with a third GKRS at the authors' institution in the period from 2010 to 2018. Telephone interviews were used to collect long-term follow-up data. Pain outcomes were measured using the Barrow Neurological Institute (BNI) pain intensity scale, with a score ≤ IIIb indicating successful treatment.

RESULTS

Twenty-two nerves in 21 patients had sufficient follow-up to determine BNI pain score outcomes. Eighteen of 22 cases had a successful third GKRS, with a median durability of pain relief of 3.88 years. There was no significant difference in the durability of pain relief after a third GKRS compared with those of institutional historical controls of prior series of first and second GKRS procedures. Ten cases had new or worsening facial numbness, with 1 case being bothersome. Four cases of toxicity other than facial numbness were reported, including 1 case of corneal abrasions and possible neurotrophic keratopathy. No cases of anesthesia dolorosa were reported. No factors predicting treatment success or the durability of pain relief were identified. Nonnumbness toxicity was more common in those with a proximally placed shot at the third GKRS.

CONCLUSIONS

A third GKRS is an effective treatment option for TN patients who have pain relapse after repeat GKRS. Pain outcomes of a third GKRS are similar to those following a first or second GKRS. Toxicity is tolerable in patients with a distally placed shot at the third GKRS.

Clinical Outcomes of Upfront Stereotactic Radiosurgery Alone for Patients With 5 to 15 Brain Metastases

BACKGROUND

The role of primary stereotactic radiosurgery (SRS) for patients with >4 brain metastases (BM) remains controversial.

OBJECTIVE

To compare the outcomes of patients treated with upfront SRS alone for 1, 2 to 4, and 5 to 15 BM and assess for predictors of clinical outcomes in the 5 to 15 BM group.

METHODS

A total of 478 patients treated with upfront SRS were stratified by number of lesions: 220 had 1 BM, 190 had 2 to 4 BM, and 68 patients had 5 to 15 BM. Overall survival and whole brain radiotherapy-free survival were estimated using the Kaplan-Meier method. The cumulative incidences of local failure and distant brain failure (DBF) were estimated using competing risks methodology. Clinicopathologic and dosimetric parameters were evaluated as predictors of survival and DBF in patients with 5 to 15 BM using Cox proportional hazards.

RESULTS

Median overall survival was 8.0, 6.3, and 4.7 mo for patients with 1, 2 to 4, and 5 to 15 BM, respectively (P = .14). One-year DBF was 27%, 44%, and 40%, respectively (P = .01). Salvage SRS and whole brain radiotherapy rates did not differ. Progressive extracranial disease and gastrointestinal primary were associated with poor survival while RCC primary was associated with increased risk of DBF. No evaluated dose-volume parameters predicted for death, neurologic death or toxicity.

CONCLUSION

SRS for 5 to 15 BM is well tolerated without evidence of an associated increase in toxicity, treatment failure, or salvage therapy. Further prospective, randomized studies are warranted to clarify the role of SRS for these patients.

Successful application of stereotactic radiosurgery for multiply recurrent Rathke’s cleft cysts

OBJECTIVE

Rathke’s cleft cysts (RCCs) are benign lesions of the sella turcica that usually come to neurosurgical attention due to compression of the optic apparatus (OA) and headaches. Treatment options for these lesions include observation, aspiration of cyst contents, or open resection of the cyst with the cyst wall. All of these options involve the potential for cyst recurrence or enlargement. In this study the authors report on a potential new therapeutic option for RCCs, i.e., stereotactic radiosurgery (SRS).

METHODS

A retrospective review was conducted of 5 patients with histologically confirmed, multiply recurrent RCCs who were treated with single-fraction SRS at a tertiary referral academic medical center.

RESULTS

The total cohort consisted of 5 female patients with an average age of 31.8 years. The most common presenting symptom was headache followed by blurry vision. The symptoms were present on average for 7 months before intervention. The median number of surgeries prior to radiosurgery was 2. The average volume of lesion treated was 0.34 cm3. The median SRS dose was 12.5 Gy prescribed to the 50% isodose line with an average prescription coverage of 96.6%. The median dose to the OA was 5 Gy. At last follow-up, 3 of 5 cysts had completely regressed, 1 had regressed by more than 50% but was still present, and 1 was stable, with an overall mean follow-up duration of 34.2 months. There were no neurological, endocrinological, or visual complications attributable to SRS during the follow-up period.

CONCLUSIONS

RCCs can be a challenging clinical entity to treat, especially when they are multiply recurrent. In patients with an average of 2 previous surgeries for resection, a single SRS session prevented recurrence universally, with an average follow-up of almost 3 years. These results indicate that further investigation of the treatment of RCCs with SRS is indicated.

Immersion Bioprinting of Tumor Organoids in Multi-Well Plates for Increasing Chemotherapy Screening Throughput

The current drug development pipeline takes approximately fifteen years and $2.6 billion to get a new drug to market. Typically, drugs are tested on two-dimensional (2D) cell cultures and animal models to estimate their efficacy before reaching human trials. However, these models are often not representative of the human body. The 2D culture changes the morphology and physiology of cells, and animal models often have a vastly different anatomy and physiology than humans. The use of bioengineered human cell-based organoids may increase the probability of success during human trials by providing human-specific preclinical data. They could also be deployed for personalized medicine diagnostics to optimize therapies in diseases such as cancer. However, one limitation in employing organoids in drug screening has been the difficulty in creating large numbers of homogeneous organoids in form factors compatible with high-throughput screening (e.g., 96- and 384-well plates). Bioprinting can be used to scale up deposition of such organoids and tissue constructs. Unfortunately, it has been challenging to 3D print hydrogel bioinks into small-sized wells due to well-bioink interactions that can result in bioinks spreading out and wetting the well surface instead of maintaining a spherical form. Here, we demonstrate an immersion printing technique to bioprint tissue organoids in 96-well plates to increase the throughput of 3D drug screening. A hydrogel bioink comprised of hyaluronic acid and collagen is bioprinted into a viscous gelatin bath, which blocks the bioink from interacting with the well walls and provides support to maintain a spherical form. This method was validated using several cancerous cell lines, and then applied to patient-derived glioblastoma (GBM) and sarcoma biospecimens for drug screening.

External jugular venous sampling for Cushing's disease in a patient with hypoplastic inferior petrosal sinuses

The authors report the case of a 30-year-old female patient with suspected Cushing's disease with an anatomical variation of hypoplastic inferior petrosal sinuses and nearly exclusive anterior drainage from the cavernous sinus, who underwent external jugular venous blood sampling with successful disease confirmation and microadenoma localization. The patient presented with signs and symptoms consistent with Cushing's syndrome, but with discordant preliminary diagnostic testing. She underwent attempted bilateral inferior petrosal sinus sampling; however, she had hypoplastic inferior petrosal sinuses bilaterally and predominantly anterior drainage from the cavernous sinus into the external jugular circulation. Given this finding, the decision was made to proceed with external jugular venous access and sampling in addition to internal jugular venous sampling. A positive adrenocorticotropic hormone (ACTH) response to corticotropin-releasing factor was obtained in the right external jugular vein alone, suggesting a right-sided pituitary microadenoma as the cause of her Cushing's disease. The patient subsequently underwent a transsphenoidal hypophysectomy that confirmed the presence of a right-sided ACTH-secreting microadenoma, which was successfully resected. She was hypocortisolemic on discharge and has had no signs of recurrence or relapse at 6 months postoperation.

Impact of brain metastasis velocity on neurologic death for brain metastasis patients experiencing distant brain failure after initial stereotactic radiosurgery

PURPOSE

Patients with high rates of developing new brain metastases have an increased likelihood of dying of neurologic death. It is unclear, however, whether this risk is affected by treatment choice following failure of primary stereotactic radiosurgery (SRS).

METHODS

From July 2000 to March 2017, 440 patients with brain metastasis were treated with SRS and progressed to have a distant brain failure (DBF). Eighty-seven patients were treated within the immunotherapy era. Brain metastasis velocity (BMV) was calculated for each patient. In general, the institutional philosophy for use of salvage SRS vs whole brain radiotherapy (WBRT) was to postpone the use of WBRT for as long as possible and to treat with salvage SRS when feasible. No further treatment was reserved for patients with poor life expectancy and who were not expected to benefit from salvage treatment.

RESULTS

Two hundred and eighty-five patients were treated with repeat SRS, 91 patients were treated with salvage WBRT, and 64 patients received no salvage radiation therapy. One-year cumulative incidence of neurologic death after salvage SRS vs WBRT was 15% vs 23% for the low- (p = 0.06), 30% vs 37% for the intermediate- (p < 0.01), and 31% vs 48% (p < 0.01) for the high-BMV group. Salvage WBRT was associated with increased incidence of neurologic death on multivariate analysis (HR 1.64, 95% CI 1.13-2.39, p = 0.01) when compared to repeat SRS. One-year cumulative incidence of neurologic death for patients treated within the immunotherapy era was 9%, 38%, and 38% for low-, intermediate-, and high-BMV groups, respectively (p = 0.01).

CONCLUSION

Intermediate and high risk BMV groups are predictive of neurologic death. The association between BMV and neurologic death remains strong for patients treated within the immunotherapy era.

Gamma Knife radiosurgery for bilateral trigeminal neuralgia

OBJECTIVE

A small subset of patients with trigeminal neuralgia (TN) will experience bilateral symptoms. Treatment in these patients is controversial because the population is heterogeneous and patients may have nonvascular etiologies of their pain. This study reports treatment outcomes in the largest cohort of patients with bilateral TN who have undergone Gamma Knife radiosurgery (GKRS) to date.

METHODS

A retrospective chart review identified 51 individual nerves in 34 patients with bilateral TN who were treated with GKRS at the authors’ institution between 2001 and 2015, with 12 nerves in 11 patients undergoing repeat GKRS for recurrent or persistent symptoms. Long-term follow-up was obtained by telephone interview. Pain outcomes were measured using the Barrow Neurological Institute (BNI) pain scale, with BNI IIIb or better considered a successful treatment.

RESULTS

There was sufficient follow-up to determine treatment outcomes for 48 individual nerves in 33 patients. Of these nerves, 42 (88%) achieved at least BNI IIIb pain relief. The median duration of pain relief was 1.9 years, and 1-, 3-, and 5-year pain relief rates were 64%, 44%, and 44%, respectively. No patients experienced bothersome facial numbness, and 1 case of anesthesia dolorosa and 2 cases of corneal dryness were reported. Patients with a history of definite or possible multiple sclerosis were significantly more likely to experience BNI IV–V relapse. There was no statistically significant difference in treatment outcomes between patients in this series versus a large cohort of patients with unilateral TN treated at the authors’ institution. There was sufficient follow-up to determine treatment outcomes for 11 individual nerves in 10 patients treated with repeat GKRS. Ten nerves (91%) improved to at least BNI IIIb after treatment. The median duration of pain relief was 2.8 years, with 1-, 3-, and 5-year rates of pain relief of 79%, 53%, and 53%, respectively. There was no statistically significant difference in outcomes between initial and repeat GKRS. One case of bothersome facial numbness and 1 case of corneal dryness were reported, with no patients developing anesthesia dolorosa with retreatment.

CONCLUSIONS

GKRS is a safe, well-tolerated treatment for patients with medically refractory bilateral TN. Efficacy of treatment appears similar to that in patients with unilateral TN. GKRS can be safely repeated in this population if necessary.

Gamma Knife Radiosurgery for Multiple Sclerosis-Associated Trigeminal Neuralgia

BACKGROUND

Trigeminal neuralgia in the setting of multiple sclerosis (MS-TN) is a challenging condition to manage that is commonly treated with Gamma Knife radiosurgery (GKRS; Elekta AB). However, data regarding the efficacy of this treatment are somewhat limited, particularly for repeat GKRS.

OBJECTIVE

To report outcomes of GKRS for MS-TN from a cohort study.

METHODS

Retrospective review of our GKRS database identified 77 cases of unilateral MS-TN (UMSTN) in 74 patients treated with GKRS between 2001 and 2016, with 37 cases undergoing repeat GKRS. Background medical history, treatment outcomes and complications, and dosimetric data were obtained by retrospective chart reviews and telephone interviews.

RESULTS

Eighty-two percent of UMSTN cases achieved Barrow Neurological Institute (BNI) IIIb or better pain relief following initial GKRS for a median duration of 1.1 yr. Estimated rates of pain relief at 1, 3, and 5 yr were 51, 39, and 29% respectively. Eighty-eight percent achieved BNI IIIb or better pain relief after repeat GKRS for a median duration of 4.0 yr. Estimated rates of pain relief at 1 and 3 yr were 70 and 54%, respectively. Median doses for initial and repeat GKRS were 85 and 80 Gy to the 100% isodose line, respectively. Those with MS-TN had a shorter duration of BNI IIIb or better pain relief after initial (4.6 vs 1.1 yr), but not repeat GKRS (3.8 vs 4.0 yr) compared to a historical cohort from our institution.

CONCLUSION

GKRS is an effective, well-tolerated treatment for patients with MS-TN. More durable relief is often achieved with repeat GKRS.

Multi-institutional validation of brain metastasis velocity, a recently defined predictor of outcomes following stereotactic radiosurgery

INTRODUCTION

Brain metastasis velocity (BMV) is a prognostic metric that describes the recurrence rate of new brain metastases after initial treatment with radiosurgery (SRS). We have previously risk stratified patients into high, intermediate, and low-risk BMV groups, which correlates with overall survival (OS). We sought to externally validate BMV in a multi-institutional setting.

METHODS

Patients from nine academic centers were treated with upfront SRS; the validation cohort consisted of data from eight institutions not previously used to define BMV. Patients were classified by BMV into low (<4 BMV), intermediate (4-13 BMV), and high-risk groups (>13 BMV). Time-to-event outcomes were estimated using the Kaplan-Meier method. Cox proportional hazards methods were used to estimate the effect of BMV and salvage modality on OS.

RESULTS

Of 2829 patients, 2092 patients were included in the validation dataset. Of these, 921 (44.0%) experienced distant brain failure (DBF). Median OS from initial SRS was 11.2 mo. Median OS for BMV < 4, BMV 4-13, and BMV > 13 were 12.5 mo, 7.0 mo, and 4.6 mo (p < 0.0001). After multivariate regression modeling, melanoma histology (β: 10.10, SE: 1.89, p < 0.0001) and number of initial brain metastases (β: 1.52, SE: 0.34, p < 0.0001) remained predictive of BMV (adjusted R² = 0.06).

CONCLUSIONS

This multi-institutional dataset validates BMV as a predictor of OS following initial SRS. BMV is being utilized in upcoming multi-institutional randomized controlled trials as a stratification variable for salvage whole brain radiation versus salvage SRS after DBF.

Immunogenicity of high-dose influenza vaccination in patients with primary central nervous system malignancy

Background

For cancer patients, rates of influenza-associated hospitalization and death are 4 times greater than that of the general population. Previously, we reported reduced immunogenicity to the standard-dose influenza vaccine in patients with central nervous system malignancy. In other poorly responding populations (eg, elderly patients), high-dose vaccination has improved efficacy and immunogenicity.

Methods

A prospective cohort study was designed to evaluate the immunogenicity of the Fluzone^® high-dose influenza vaccine in brain tumor patients. Data on diagnosis, active oncologic treatment, and immunologic status (eg, CD4 count, CD8 count, CD4:CD8 ratio) were collected. All patients received the high-dose vaccine (180 µg). Hemagglutination inhibition titers were measured at baseline, day 28, and 3 months following vaccination to determine seroconversion (≥4-fold rise) and seroprotection (titer ≥1:40), which were compared to our prior results.

Results

Twenty-seven patients enrolled. Diagnoses included high-grade glioma (85%), CNS lymphoma (11%), and meningioma (4%). Treatment at enrollment included glucocorticoids (n = 8, 30%), radiation (n = 2, 7%), and chemotherapy (n = 9, 33%). Posttreatment lymphopenia (PTL, CD4 ≤ 200) was observed in 4 patients (15%). High-dose vaccination was well tolerated with no grade III-IV toxicity. Overall, seroconversion rates for the A/H1N1, A/H3N2, and B vaccine strains were significantly higher than in our prior study: 65% vs 37%, 69% vs 23%, and 50% vs 23%, respectively (all P < .04). Seroconversion was universally poor in patients with PTL. While seroprotection at 3 months declined in our prior study, no drop was observed following high-dose vaccination in this cohort.

Conclusions

The immunologic response to HD influenza vaccination was higher in this cohort than standard-dose influenza vaccination in our prior report. These findings mirror those in elderly patients where high-dose vaccination is the standard of care and raise the possibility of an immunosenescence phenotype.

Laser ablation after stereotactic radiosurgery: a multicenter prospective study in patients with metastatic brain tumors and radiation necrosis

OBJECTIVE

Laser Ablation After Stereotactic Radiosurgery (LAASR) is a multicenter prospective study of laser interstitial thermal (LITT) ablation in patients with radiographic progression after stereotactic radiosurgery for brain metastases.

METHODS

Patients with a Karnofsky Performance Scale (KPS) score ≥ 60, an age > 18 years, and surgical eligibility were included in this study. The primary outcome was local progression-free survival (PFS) assessed using the Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria. Secondary outcomes were overall survival (OS), procedure safety, neurocognitive function, and quality of life.

RESULTS

Forty-two patients—19 with biopsy-proven radiation necrosis, 20 with recurrent tumor, and 3 with no diagnosis—were enrolled. The median age was 60 years, 64% of the subjects were female, and the median baseline KPS score was 85. Mean lesion volume was 6.4 cm3 (range 0.4–38.6 cm3). There was no significant difference in length of stay between the recurrent tumor and radiation necrosis patients (median 2.3 vs 1.7 days, respectively). Progression-free survival and OS rates were 74% (20/27) and 72%, respectively, at 26 weeks. Thirty percent of subjects were able to stop or reduce steroid usage by 12 weeks after surgery. Median KPS score, quality of life, and neurocognitive results did not change significantly for either group over the duration of survival. Adverse events were also similar for the two groups, with no significant difference in the overall event rate. There was a 12-week PFS and OS advantage for the radiation necrosis patients compared with the recurrent tumor or tumor progression patients.

CONCLUSIONS

In this study, in which enrolled patients had few alternative options for salvage treatment, LITT ablation stabilized the KPS score, preserved quality of life and cognition, had a steroid-sparing effect, and was performed safely in the majority of cases.

Clinical trial registration no.: NCT01651078 (clinicaltrials.gov)

Immunotherapy is associated with improved survival and decreased neurologic death after SRS for brain metastases from lung and melanoma primaries

Background

The effect of immunotherapy on brain metastasis patients remains incompletely understood. Our goal was to evaluate its effect on survival, neurologic death, and patterns of failure after stereotactic radiosurgery (SRS) without prior whole-brain radiation therapy (WBRT) in patients with lung and melanoma primaries metastatic to the brain.

Methods

We performed a retrospective analysis of 271 consecutive lung or melanoma patients treated with upfront SRS for brain metastases between 2013 and 2018. Of these patients, 101 (37%) received immunotherapy and 170 (63%) did not. Forty-three percent were treated with nivolumab. Thirty-seven percent were treated with pembrolizumab. Fifteen percent were treated with ipilimumab. One percent were treated with a combination of nivolumab and ipilimumab. One percent were treated with atezolizumab. Three percent were treated with another immunotherapy regimen. Survival was estimated by the Kaplan-Meier method and cumulative incidences of neurologic death, and local and distant brain failure were estimated using death as a competing risk.

Results

The median overall survival (OS) of patients treated with immunotherapy vs without was 15.9 (95% CI: 13.3 to 24.8) vs 6.1 (95% CI: 5.1 to 8.8) months (P < .01). The 1-year cumulative incidence of neurologic death was 9% in patients treated with immunotherapy vs 23% in those treated without (P = .01), while nonneurologic death was not significantly different (29% vs 41%, P = .51). Median brain metastasis velocity (BMV) did not differ between groups, and rates of salvage SRS and WBRT were similar.

Conclusions

The use of immunotherapy in patients with lung cancer or melanoma metastatic to the brain treated with SRS is associated with improved OS and decreased incidence of neurologic death.

Staged Stereotactic Radiosurgery for Large Brain Metastases: Local Control and Clinical Outcomes of a One-Two Punch Technique

BACKGROUND

Treatment options are limited for large, unresectable brain metastases.

OBJECTIVE

To report a single institution series of staged stereotactic radiosurgery (SRS) that allows for tumor response between treatments in order to optimize the therapeutic ratio.

METHODS

Patients were treated with staged SRS separated by 1 mo with a median dose at first SRS of 15 Gy (range 10-21 Gy) and a median dose at second SRS of 14 Gy (range 10-18 Gy). Overall survival was evaluated using the Kaplan-Meier method. Cumulative incidences were estimated for neurological death, radiation necrosis, local failure (marginal or central), and distant brain failure. Absolute cumulative dose-volume histogram was created for each treated lesion. Logistic regression and competing risks regression were performed for each discrete dose received by a certain volume.

RESULTS

Thirty-three patients with 39 lesions were treated with staged radiosurgery. Overall survival at 6 and 12 mo was 65.0% and 60.0%, respectively. Cumulative incidence of local failure at 6 and 12 mo was 3.2% and 13.3%, respectively. Of the patients who received staged therapy, 4 of 33 experienced local failure. Radiation necrosis was seen in 4 of 39 lesions. Two of 33 patients experienced a Radiation Therapy Oncology Group toxicity grade > 2 (2 patients had grade 4 toxicities). Dosimetric analysis revealed that dose (Gy) received by volume of brain (ie, VDose(Gy)) was associated with radiation necrosis, including the range V44.5Gy to V87.8Gy.

CONCLUSION

Staged radiosurgery is a safe and effective option for large, unresectable brain metastases. Prospective studies are required to validate the findings in this study.

Initial brain metastasis velocity: does the rate at which cancers first seed the brain affect outcomes?

PURPOSE/OBJECTIVE(S)

Brain metastasis velocity (BMV) is a metric that describes the rate of development of new brain metastases (BM) after initial stereotactic radiosurgery (SRS). A limitation in the application of BMV is it cannot be applied until time of first BM failure after SRS. We developed initial BM velocity (iBMV), a new metric that accounts for the number of BM at first SRS and the time since initial cancer diagnosis.

MATERIALS/METHODS

We reviewed patients with BM treated at our institution with upfront SRS without WBRT. iBMV was calculated as the number of BM at initial SRS divided by time (years) from initial cancer diagnosis to first SRS. We performed a linear regression to correlate BMV as a continuous variable and with low, intermediate, and high BMV risk groups. Kaplan-Meier estimation of OS was calculated from time of first SRS to death. iBMV was not calculated for patients who presented with BM at initial cancer diagnosis.

RESULTS

994 patients were treated with upfront SRS without WBRT between 2000 and 2017. Median OS was 8.5 mos. 595 (60%) patients developed BM after cancer diagnosis and median time to first SRS from time of initial diagnosis was 2.2 years. Median iBMV was 0.79 BM/year. iBMV correlated with BMV (β = 1.57 p = 0.021) and independently predicted for mortality [Cox proportional hazard ratio (HR) 1.11, p = 0.036] after accounting for histology, number of initial brain metastases (HR 1.03, p = 0.32), time from cancer diagnosis to SRS (HR 0.98, p = 0.157) in a multivariate model.

CONCLUSION

iBMV correlates with BMV and OS. With further validation, iBMV could serve as a metric to risk stratify patients for WBRT or SRS at time of first BM presentation.

The Protective Action Encoding of Serotonin Transients in the Human Brain

The role of serotonin in human brain function remains elusive due, at least in part, to our inability to measure rapidly the local concentration of this neurotransmitter. We used fast-scan cyclic voltammetry to infer serotonergic signaling from the striatum of 14 brains of human patients with Parkinson's disease. Here we report these novel measurements and show that they correlate with outcomes and decisions in a sequential investment game. We find that serotonergic concentrations transiently increase as a whole following negative reward prediction errors, while reversing when counterfactual losses predominate. This provides initial evidence that the serotonergic system acts as an opponent to dopamine signaling, as anticipated by theoretical models. Serotonin transients on one trial were also associated with actions on the next trial in a manner that correlated with decreased exposure to poor outcomes. Thus, the fluctuations observed for serotonin appear to correlate with the inhibition of over-reactions and promote persistence of ongoing strategies in the face of short-term environmental changes. Together these findings elucidate a role for serotonin in the striatum, suggesting it encodes a protective action strategy that mitigates risk and modulates choice selection particularly following negative environmental events.

Gamma Knife Stereotactic Radiosurgery for the Treatment of Brain Metastases from Primary Tumors of the Urinary Bladder

BACKGROUND/AIMS

Brain metastases from bladder cancer are rare and published outcomes data are sparse. To date, no institutions have reported a series of patients with brain metastases from bladder cancer treated with stereotactic radiosurgery (SRS). Our aim was to identify patients with brain metastases from bladder primaries treated with SRS with or without surgical resection and report the clinical outcomes.

METHODS

Patients meeting eligibility criteria at our institution between 2000 and 2017 were included. The clinical variables of interest, including overall survival (OS), local recurrence, V12, distant brain failure (DBF), and initial brain metastases velocity, were calculated. Cox proportional hazards analysis was performed to identify predictors of time-to-event outcomes.

RESULTS

A total of 14 patients were included. The median OS from the time of treatment was 2.1 months. Factors predictive of OS include intracranial resection (HR 0.21, p = 0.03). The cumulative incidence of local failure was 21% at 6 months and 30% at 12 months. The cumulative incidence of DBF at 6 and 12 months was 23 and 31%, respectively.

CONCLUSIONS

The prognosis in this patient population remains guarded. Factors associated with improved survival include intracranial resection. Future, prospective work is needed to further define optimal management.

Surgical Considerations in the Optimal Management of Patients with Malignant Brain Tumors

OPINION STATEMENT

Advances in technology are revolutionizing medicine and the limits of what we can offer to our patients. In neurosurgery, technology continues to reduce morbidity, increase surgical accuracy, facilitate tissue acquisition, and promote novel techniques for prolonging survival in patients with neuro-oncologic disease. Surgery has been the backbone of glioma diagnosis and treatment by providing adequate, high quality material for precise histologic diagnosis, and genomic characterization in the setting of significant intratumoral heterogeneity, thus allowing personalized treatment selection in the clinic. The ability to obtain and accurately measure the maximal extent of resection in glioma surgery also remains a central role of the neurosurgeon in managing this cancer. To meet these goals, today's operating room has transformed from the traditional operating table and anesthesia machine to include neuronavigation instrumentation, intraoperative computed tomography, and magnetic resonance imaging scanners, advanced surgical microscopes fitted with fluorescent light filters, and electrocorticography machines. While surgeons, oncologists, and radiation oncologists all play unique critical roles in the care of patients with malignant gliomas, familiarity with developing techniques in complimentary subspecialties can enhance coordination of patient care, research productivity, professional interactions, and patient confidence and comfort with the physician team. Herein, we provide a summary of the advances in the field of neurosurgical oncology which allow more precise and optimal surgical resection for patients with malignant gliomas.