Bilateral Laser Interstitial Thermal Therapy for Butterfly Gliomas Compared With Needle Biopsy: A Preliminary Survival Study

BACKGROUND AND OBJECTIVES

Bilateral/butterfly glioblastoma (bGBM) has a poor prognosis. Resection of these tumors is limited due to severe comorbidities that arise from surgical procedures. Laser interstitial thermal therapy (LITT) offers a minimally invasive cytoreductive therapy for deep-seated tumors such as bGBM. The objective of this study was to evaluate the safety of bilateral LITT in patients with bGBM.

METHODS

Medical records of all consecutive patients diagnosed with bGBM by a single surgeon at a single institution from January 2014 to August 2022 were reviewed. Clinical, safety, and radiographic volumetric data were obtained. In addition, an exploratory analysis of survival was performed.

RESULTS

A total of 25 patients were included; 14 underwent biopsy only, and 11 underwent biopsy + LITT (7 underwent bilateral and 4 underwent unilateral LITT). No (0%) intraoperative or postoperative complications were recorded in the treatment group. Tumor volume negatively correlated with extent of treatment (r 2 = 0.44, P = .027). The median progression-free survival was 2.8 months in the biopsy-only group and 5.5 months in the biopsy + LITT group ( P = .026). The median overall survival was 4.3 months in the biopsy-only group and 10.3 months in the biopsy + LITT group ( P = .035).

CONCLUSION

Bilateral LITT for bGBM can be safely performed and shows early improvement of the progression-free survival and long-term survival outcomes of these patients.

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

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

Treatment of Chiari malformations with craniovertebral junction anomalies: Where do we stand today?

Background

Chiari malformation type 1 (CM-1) is characterized by cerebellar tonsil herniation through the foramen magnum and can be associated with additional craniovertebral junction anomalies (CVJA). The pathophysiology and treatment for CM-1 with CVJA (CM-CVJA) is debated.

Objective

To evaluate the trends and outcomes of surgical interventions for patients with CM-CVJA.

Methods

A systematic review of the literature was performed to obtain articles describing surgical interventions for patients with CM-CVJA. Articles included were case series describing surgical approach; reviews were excluded. Variables evaluated included patient characteristics, approach, and postoperative outcomes.

Results

The initial query yielded 403 articles. Twelve articles, published between 1998-2020, met inclusion criteria. From these included articles, 449 patients underwent surgical interventions for CM-CVJA. The most common CVJAs included basilar invagination (BI) (338, 75.3%), atlantoaxial dislocation (68, 15.1%) odontoid process retroflexion (43, 9.6%), and medullary kink (36, 8.0%). Operations described included posterior fossa decompression (PFD), transoral (TO) decompression, and posterior arthrodesis with either occipitocervical fusion (OCF) or atlantoaxial fusion. Early studies described good results using combined ventral and posterior decompression. More recent articles described positive outcomes with PFD or posterior arthrodesis in combination or alone. Treatment failure was described in patients with PFD alone that later required posterior arthrodesis. Additionally, reports of treatment success with posterior arthrodesis without PFD was seen.

Conclusion

Patients with CM-CVJA appear to benefit from posterior arthrodesis with or without decompressive procedures. Further definition of the pathophysiology of craniocervical anomalies is warranted to identify patient selection criteria and ideal level of fixation.

The Neurosurgery Match: COVID-19 Comparison and Bibliometric Analysis

BACKGROUND

Because of the effect of COVID-19 on academic opportunities, as well as limitations on travel, away rotations and in-person interviews, COVID-19-related changes could impact the neurosurgical resident demographics. Our aim was to retrospectively review the demographics of the previous 4 years of neurosurgery residents, provide bibliometric analysis of successful applicants, and analyze for the effects of COVID-19 on the match cycle.

METHODS

All American Association of Neurological Surgeons' residency program websites were examined for a list of demographic characteristics for current postgraduate years 1 to 4. Gathered information included gender, undergraduate and medical institution and state, medical degree status, and prior graduate programs.

RESULTS

A total of 114 institutions and 946 residents were included in the final review. Most (676, or 71.5%) of the residents included in the analysis were male. Of the 783 who studied within the United States, 221 (28.2%) residents stayed within the same state of his or her medical school. Fewer residents (104 of 555, or 18.7%) stayed within the same state of his or her undergraduate school. Demographic information and geographic switching relative to medical school, undergraduate school, and hometown showed no significant changes between pre-COVID-19 and COVID-19-matched cohorts overall. The median number of publications per resident significantly increased for the COVID-19-matched cohort (median, 1; interquartile range [IQR], 0-4.75) when compared with the non-COVID-19-matched cohort (median, 1; IQR, 0-3, P = 0.004), as did first author publications (median, 1; IQR, 0-1 vs. median, 1; IQR, 0-1; P = 0.015), respectively. The number of residents matching into the same region in the Northeast relative to undergraduate degree was significantly greater after COVID-19 (56 [58%] versus 36 [42%], P = 0.026). The West demonstrated a significant increase in the mean number of total publications (4.0 ± 8.5 vs. 2.3 ± 4.2, P = 0.02) and first author publications (1.24 ± 2.33 vs. 0.68 ± 1.47, P = 0.02) after COVID-19, with the increase in first author publications being significant in a test of medians.

CONCLUSIONS

Herein we characterized the most recently matched neurosurgery applicants, paying particular attention to changes over time in relation to the onset of the pandemic. Apart from publication volume, characteristics of residents and geographical preferences did not change with the influence of COVID-19-induced changes in the application process.

Surgical management of brain metastasis from ovarian cancer: a systematic review and case series

OBJECTIVE

Ovarian cancer is a rare origin of brain metastasis (BM), with an incidence of only 1%-3%. Consequently, the literature is sparse, and no treatment consensus guideline is available for ovarian BM. The authors conducted a systematic review of ovarian BM and performed a combined pooled cohort survival analysis with their case series.

METHODS

A systematic review of PubMed, Scopus, and Web of Science consistent with PRISMA guidelines along with an institutional retrospective chart review was conducted. Inclusion criteria for the systematic review included patients with confirmed BM and primary ovarian cancer, reported perioperative complications and outcomes, differentiated histology, and explicitly reported individual patient data. Reviews, commentaries, technical notes, and articles without English-language translations were excluded. The Newcastle-Ottawa Quality Assessment Scale was used independently by the first and second authors to assess the quality of each article. The authors performed univariate and multivariate analyses of several survival prognostic factors. Kaplan-Meier curves were generated for significant prognostic factors in the univariate analysis.

RESULTS

A total of 48 patients with individual data across 34 studies and 8 patients from the authors' institution were included. All patients (n = 56) underwent resection for BM; 83.9% received adjuvant radiotherapy following surgery and 41.1% of patients received adjuvant chemotherapy. The median progression-free survival was 12 months (range 2-43 months). The median overall survival was 9 months (range 1-49 months). On univariate analysis, a single BM and no extracranial metastasis conferred a survival benefit, while clear cell carcinoma as the primary histology corresponded to worsened OS. Multivariable analysis showed that age > 50 years (p = 0.002) and > 1 BM (p < 0.001) were risk factors for poor prognosis. Protective factors included the addition of the following multimodal adjuvant therapy with surgery: radiotherapy (p = 0.002), chemotherapy and radiotherapy (p = 0.005), and stereotactic radiosurgery (p = 0.002).

CONCLUSIONS

Although the scarcity of published individual patient data hinders the determination of optimal management, the authors' analysis highlights that multimodal therapies, a single cranial lesion, and age < 50 years are associated with increased survival for patients with ovarian BMs.

Two-stage radiosurgery for large brain metastases: a systematic review and meta-analysis of clinical outcomes

OBJECTIVE

Brain metastases (BMs) are the most common intracranial tumors. In several cases, they present as large masses, which are related to a worse prognosis and more complex therapeutic alternatives. Staged radiosurgery is reported to achieve local control with minimal radiation-related adverse events in BMs. However, no methodological consensus has been achieved in its use for large brain metastases (LBMs; > 2 cm). Therefore, the authors aimed to determine the effectiveness and safety of 2-stage Gamma Knife radiosurgery (GKRS) for LBMs, in order to optimize patients' postoperative course.

METHODS

A systematic review of available literature was run in PubMed/MEDLINE, Scopus, Web of Science, Cochrane (OvidSP), and Google Scholar for works published up to December 14, 2022. Nonrandomized clinical trials, case series, and cohort studies were included. The risk of bias was assessed using the Risk of Bias in Nonrandomized Studies-of Interventions (ROBINS-I) and Joanna Briggs Institute tools. Pooled mean difference and rates estimates were calculated by a random-effects model meta-analysis. The degree of heterogeneity was expressed using the I2 statistic. A subgroup analysis was performed. Ultimately, the certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessment.

RESULTS

Fourteen studies met the eligibility criteria (cohorts, case series, and nonrandomized clinical trials), including 958 patients. A total pooled mean volume reduction of 6.27 cm3 (95% CI 5.67-6.88 cm3) and 54.36% (95% CI 39.92%-68.79%) after 2-stage GKRS was reported. Pooled rates of complete response (44.63%; 95% CI 26.50%-64.31%), neurological mortality (16.19%; 95% CI 7.68%-30.98%), and all-cause mortality (47.92%; 95% CI 28.04%-68.49%) were calculated. Overall certainty of evidence ranged from very low to moderate.

CONCLUSIONS

Two-stage GKRS is an effective and safe approach for the treatment of LBMs. Nevertheless, the lack of available literature and the weak methodological approaches used determine a low to very low certainty of evidence and cannot provide robust evidence to recommend this intervention. Therefore, it is necessary to conduct higher-quality primary studies.

Human endogenous retrovirus K contributes to a stem cell niche in glioblastoma

Human endogenous retroviruses (HERVs) are ancestral viral relics that constitute nearly 8% of the human genome. Although normally silenced, the most recently integrated provirus HERV-K (HML-2) can be reactivated in certain cancers. Here, we report pathological expression of HML-2 in malignant gliomas in both cerebrospinal fluid and tumor tissue that was associated with a cancer stem cell phenotype and poor outcomes. Using single-cell RNA-Seq, we identified glioblastoma cellular populations with elevated HML-2 transcripts in neural progenitor-like cells (NPC-like) that drive cellular plasticity. Using CRISPR interference, we demonstrate that HML-2 critically maintained glioblastoma stemness and tumorigenesis in both glioblastoma neurospheres and intracranial orthotopic murine models. Additionally, we demonstrate that HML-2 critically regulated embryonic stem cell programs in NPC-derived astroglia and altered their 3D cellular morphology by activating the nuclear transcription factor OCT4, which binds to an HML-2-specific long-terminal repeat (LTR5Hs). Moreover, we discovered that some glioblastoma cells formed immature retroviral virions, and inhibiting HML-2 expression with antiretroviral drugs reduced reverse transcriptase activity in the extracellular compartment, tumor viability, and pluripotency. Our results suggest that HML-2 fundamentally contributes to the glioblastoma stem cell niche. Because persistence of glioblastoma stem cells is considered responsible for treatment resistance and recurrence, HML-2 may serve as a unique therapeutic target.

Management of Atypical and Anaplastic Meningiomas

Meningiomas are the most prevalent primary tumor of central nervous system origin, and although most of these neoplasms are benign, a small proportion exemplifies an aggressive profile characterized by high recurrence rates, pleomorphic histology, and overall resistance to standard treatment. Standard initial therapy for malignant meningiomas includes maximal safe surgical resection followed by focal radiation. The role for chemotherapy during recurrence of these aggressive meningiomas is less clear. Prognosis is poor, and recurrence of malignant meningiomas is high. This article provides an overview of atypical and anaplastic "malignant" meningiomas, their treatment, and ongoing research looking for more effective treatments.

Oncolytic Virotherapy for High-Grade Glioma and Current Evidence and Factors to Consider for Incorporation into Clinical Practice

Brain tumor incidence is on the rise, and glioblastoma comprises the majority of primary tumors. Despite maximal safe resection and adjuvant chemoradiation, median survival for high-grade glioma remains poor. For this reason, it is important to develop and incorporate new treatment strategies. Oncolytic virotherapy has emerged as a viable new therapeutic entity to fill this gap. Preclinical research has shown oncolytic virotherapy to be a robust and effective treatment option for brain tumors, and clinical trials for both adult and pediatric high-grade glioma are underway. The unique and protected environment of the nervous system, in part due to the blood-brain barrier, prevents traditional systemic therapies from achieving adequate penetration. Brain tumors are also heterogenous in nature due to their diverse molecular profiles, further complicating systemic treatment efforts. Oncolytic viruses may serve to fill this gap in brain tumor treatment given their amenability to genetic modification and ability to target unique tumor epitopes. In addition, direct inoculation of the oncolytic virus agent to the tumor bed following surgical resection absolves risk of systemic side effects and ensures adequate delivery. As virotherapy transitions from bench to bedside, it is important to discuss factors to make this transition more seamless. In this article, we describe the current clinical evidence as it pertains to oncolytic virotherapy and the treatment of brain tumors as well as factors to consider for its incorporation into neurosurgical workflow.

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

PURPOSE

The postoperative period after laser interstitial thermal therapy (LITT) is marked by a temporary increase in volume, which can impact the accuracy of radiographic assessment. The current criteria for progressive disease (PD) suggest that a 20% increase in size of brain metastasis (BM) assessed in 6-12 weeks intervals should be considered as local progression (LP). However, there is no agreement on how LP should be defined in this context. In this study, we aimed to statistically analyze which tumor volume variations were associated with LP.

METHODS

We analyzed 40 BM that underwent LITT between 2013 and 2022. For this study, LP was defined following radiographic features. A ROC curve was generated to evaluate volume change as a predictor of LP and find the optimal cutoff point. A logistic regression analysis and Kaplan Meier curves were performed to assess the impact of various clinical variables on LP.

RESULTS

Out of 40 lesions, 12 (30%) had LP. An increase in volume of 25.6% from baseline within 120-180 days after LITT presented a 70% sensitivity and 88.9% specificity for predicting LP (AUC: 0.78, p = 0.041). The multivariate analysis showed a 25% increase in volume between 120 and 180 days as a negative predictive factor (p = 0.02). Volumetric changes within 60-90 days after LITT did not predict LP (AUC: 0.57; p = 0.61).

CONCLUSION

Volume changes within the first 120 days after the procedure are not independent indicators of LP of metastatic brain lesions treated with LITT.

Development of an enhanced recovery protocol after laser ablation surgery protocol: a preliminary analysis

Background

Enhanced recovery after surgery (ERAS) programs are a model of care that aim to improve patient outcomes, reduce complications, and facilitate recovery while reducing healthcare-associated costs and admission length. While such programs have been developed in other surgical subspecialties, there have yet to be guidelines published specifically for laser interstitial thermal therapy (LITT). Here we describe the first multidisciplinary ERAS preliminary protocol for LITT for the treatment of brain tumors.

Methods

Between the years 2013 and 2021, 184 adult patients consecutively treated with LITT at our single institution were retrospectively analyzed. During this time, a series of pre, intra, and postoperative adjustments were made to the admission course and surgical/anesthesia workflow with the goal of improving recovery and admission length.

Results

The mean age at surgery was 60.7 years with a median preoperative Karnofsky performance score of 90 ± 13. Lesions were most commonly metastases (50%) and high-grade gliomas (37%). The mean length of stay was 2.4 days, with the average patient being discharged 1.2 days after surgery. There was an overall readmission rate of 8.7% with a LITT-specific readmission rate of 2.2%. Three of 184 patients required repeat intervention in the perioperative period, and there was one perioperative mortality.

Conclusions

This preliminary study shows the proposed LITT ERAS protocol to be a safe means of discharging patients on postoperative day 1 while preserving outcomes. Although future prospective work is needed to validate this protocol, results show the ERAS approach to be promising for LITT.

Synchronous Posterior and Anterior Pituitary Tumors: A Case Report of a Hypothetic Paracrine Relationship

Tumors of the posterior pituitary are a distinct group of low-grade sellar neoplasms. Furthermore, the coexistence with an anterior pituitary tumor is extremely unlikely and could not be a mere coincidence and could be a paracrine relationship. Here, we present a case of 41-year-old woman with Cushing syndrome and two pituitary masses on magnetic resonance imaging. Histologic examination shows two distinct lesions. The first consisted of a pituitary adenoma with intense adrenocorticotropic hormone immunostaining and the second lesion consisted of a proliferation of pituicytes arranged in vague fascicles or pituicytoma. After a narrative review of the literature, we found that synchronous pituitary adenoma and a thyroid transcription factor 1 (TTF-1) pituitary tumor were only reported eight times in the past. These patients included two granular cell tumors and six pituicytomas and all of them coexisted with pituitary adenomas, seven functioning and one nonfunctioning. We analyze the hypothesis of a possible paracrine relationship for this concomitance, but this exceedingly rare situation is still a matter of debate. To the best of our knowledge, our case represents the ninth case of a TTF-1 pituitary tumor coexisting with a pituitary adenoma.

Newly Diagnosed Adult Basal Ganglia Gliomas Treated With Laser Interstitial Thermal Therapy: A Comparative Cohort With Needle Biopsy

BACKGROUND

Few cytoreductive surgical tools are available for newly diagnosed basal ganglia gliomas. Current reports showed high associated morbidity and mortality. Given their deep localization, laser interstitial thermal therapy (LITT) is still a rare indication. Moreover, few reports account for which of the available options have better outcomes.

OBJECTIVE

To retrospectively analyze our experience with LITT and compare its safety, feasibility, and efficacy with needle biopsy for the management of adult basal ganglia gliomas.

METHODS

Twenty-two patients with gliomas from the midline (e.g. thalamus and lenticular nucleus) managed with either LITT/biopsy or needle biopsy from 2015 to 2021 were included. Records regarding location, diagnosis, Karnofsky Performance Score, length of hospital stay, preoperative lesion and ablation volume, perioperative complications, and data of adjuvant treatment were collected. Overall survival was evaluated with Kaplan-Meier analysis.

RESULTS

Seven patients had LITT, and 15 underwent biopsy. The overall mean age was 60.9 years (25-82 years). The average tumor volume in the former was 16.99 cm 3 and 17.65 cm 3 in the latter. No postsurgical complications were found in the LITT group, and 1 patient had a postsurgical hemorrhage after biopsy. The mean overall survival was 20.28 ± 9.63 months in the LITT group, which was greater but not statistically significant than in the biopsy group (13.85 ± 4.48 months; P = .78).

CONCLUSION

Our results show that laser ablation may be both feasible and safe in adult basal ganglia gliomas. Given the lack of safe cytoreductive treatment options, LITT should be considered as a valid choice for these patients.

Trends in Leadership Among Neurosurgical Oncology Fellowships

OBJECTIVE

To examine current neurosurgical oncology leadership trends and provide a guide for those interested in obtaining fellowship directorship, we investigated fellowship director (FD) demographic, educational and leadership characteristics.

METHODS

The American Association of Neurological Surgeons (AANS) Academic Fellowship Directory and Committee on Advanced Subspecialty Training (CAST) websites were reviewed for current U.S. program FDs for which data was collected using online resources and surveys.

RESULTS

23 total FDs (20 males and 3 females) were represented whose mean age was 52.4 years (SD = 8.7). Our analysis found 65% of current neurosurgical oncology FD's to be singularly trained in neurosurgical oncology, with 8.7% possessing multiple fellowships and 34.8% possessing additional degrees. Fellowship programs producing the most FDs were University of Texas MD Anderson (4), Memorial Sloan Kettering (3) and University of Miami (2). FDs possessed an average of 148 publications, 6423 citations, and an h-index of 33.9. H-index had a high-positive correlation with age and time from residency graduation, but not duration of FD appointment. Among survey respondents, 91.7% reported membership and 75% reported leadership positions among national academic societies, while 66.7% reported holding journal-editorial positions. The mean age of FD appointment was 46.8 years with a mean time from fellowship completion to FD appointment of 10.0 years.

CONCLUSIONS

Through the characterization of current leaders in the field, we provide valuable information with regards to training location trends, research productivity goals, career timelines, and target journal/national academic society involvement worth consideration among young trainees when making career decisions and plans.

Surgical Approaches to Thalamic Gliomas: A Systematic Review

BACKGROUND

Adult thalamic gliomas (ATGs) present a surgical challenge given their depth and proximity to eloquent brain regions. Choosing a surgical approach relies on different clinical variables such as anatomical location and size of the tumor. However, conclusive data regarding how these variables influence the balance between extent of resection and complications are lacking. We aim to systematically review the literature to describe the current surgical outcomes of ATG and to provide tools that may improve the decision-making process.

METHODS

Literature regarding the surgical management of ATG patients was reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four databases were queried and a description of clinical characteristics and survival analysis were performed. An individual patient data analysis was conducted when feasible.

RESULTS

A total of 462 patients were included from 13 studies. The mean age was 39.8 years with a median preoperative Karnofsky performance scale of 70. The lateral approaches were most frequently used (74.9%), followed by the interhemispheric (24.2%). Gross total and subtotal/partial resections were achieved in 81%, and 19% of all cases, respectively. New permanent neurological deficits were observed in 51/433 patients (11.8%). individual patient data was pooled from 5 studies (n = 71). In the multivariate analysis, tumors located within the posterior thalamus had worse median overall survival compared to anterior gliomas (14.5 vs. 27 months, P = 0.003).

CONCLUSIONS

Surgical resection of ATGs can increase survival but at the risk of operative morbidity. Knowing which factors impact survival may allow neurosurgeons to propose a more evidence-based treatment to their patients.

Frontal lobe low-grade tumors seizure outcome: a pooled analysis of clinical predictors

OBJECTIVE

Seizures present in 50-90 % of cases with low-grade brain tumors. Frontal lobe epilepsy is associated with dismal seizure outcomes compared to temporal lobe epilepsy. Our objective is to conduct a systematic review, report our case series, and perform a pooled analysis of clinical predictors of seizure outcomes in frontal lobe low-grade brain tumors.

METHODS

Searches of five electronic databases from January 1990 to June 2022 were reviewed following PRISMA guidelines. Individual patient data was extracted from 22 articles that fit the inclusion criteria. A single-surgeon case series from our institution was also retrospectively reviewed and analyzed through a pooled cohort of 127 surgically treated patients with frontal lobe low-grade brain tumors.

RESULTS

The mean age at surgery was 30.8 years, with 50.4 % of patients diagnosed as oligodendrogliomas. The majority of patients (81.1 %) were seizure-free after surgery (Engel I). On the multivariate analysis, gross total resection (GTR) (OR = 8.77, 95 % CI: 1.99-47.91, p = 0.006) and awake resection (OR = 9.94, 95 % CI: 1.93-87.81, p = 0.015) were associated with seizure-free outcome. A Kaplan-Meier curve showed that the probability of seizure freedom fell to 92.6 % at 3 months, and to 85.5 % at 27.3 months after surgery.

CONCLUSION

Epilepsy from tumor origin demands a balance between oncological management and epilepsy cure. Our pooled analysis suggests that GTR and awake resections are positive predictive factors for an Engel I at more than 6 months follow-up. To validate these findings, a longer-term follow-up and larger cohorts are needed.

Management of a Growth Hormone-Secreting Pituitary Macroadenoma Associated With Idiopathic Intracranial Hypertension and an Empty Sella

Idiopathic intracranial hypertension (IIH) is a -condition associated with elevated intracranial pressure (ICP) and frequently presents with headaches, papilledema, and visual loss. Rarely, IIH has been reported in association with acromegaly. Although removal of the tumor may reverse this process, elevated ICP, especially in the setting of an otherwise empty sella, may result in a cerebrospinal fluid (CSF) leak that is exceedingly difficult to manage. We present the first case of a patient with a functional pituitary adenoma causing acromegaly associated with IIH and an otherwise empty sella and discuss our management paradigm for this rare condition.

Radical supramaximal resection for newly diagnosed left-sided eloquent glioblastoma: safety and improved survival over gross-total resection

OBJECTIVE

Supramaximal resection (SMR) has arisen as a possible surrogate to gross-total resection (GTR) to improve survival in newly diagnosed glioblastoma (nGBM). However, SMR has traditionally been limited to noneloquent regions and its feasibility in eloquent nGBM remains unclear. The authors conducted a retrospective multivariate propensity-matched analysis comparing survival outcomes for patients with left-sided eloquent nGBM undergoing SMR versus GTR.

METHODS

A retrospective review was performed of all patients at our institution who underwent SMR or GTR of a left-sided eloquent nGBM during the period from 2011 to 2020. All patients underwent some form of preoperative or intraoperative functional mapping and underwent awake or asleep craniotomy (craniotomy under general anesthesia); however, awake craniotomy was performed in the majority of patients and the focus of the study was SMR achieved via awake craniotomy and functional mapping with lesionectomy and additional peritumoral fluid attenuated inversion recovery (FLAIR) resection. Propensity scores were generated controlling for age, tumor location, and preoperative Karnofsky Performance Status (KPS) score with the nearest-neighbor algorithm.

RESULTS

A total of 102 patients (48 SMR, 54 GTR) were included in this study. The median overall survival (OS) and progression-free survival (PFS) for patients receiving SMR were 22.9 and 5.1 months, respectively. Propensity matching resulted in a final cohort of 27 SMR versus 27 GTR patients. SMR conferred improved OS (21.55 vs 15.49 months, p = 0.0098) and PFS (4.51 vs 3.59 months, p = 0.041) compared to GTR. There was no significant difference in postoperative complication rates or KPS score in SMR compared with GTR patients (p = 0.236 and p = 0.736, respectively). In patients receiving SMR, improved OS and PFS showed a dose-dependent relationship with extent of FLAIR resection (EOFR) on log-rank test for trend (p < 0.001).

CONCLUSIONS

SMR by means of awake craniotomy with functional mapping for left-sided eloquent nGBM is safe and confers a survival benefit compared to GTR obtained with lesionectomy alone while preserving postoperative neurological integrity. When tolerated, greater EOFR with SMR may be associated with improved survival.

Multidisciplinary Postoperative Care Pathway to Reduce Readmissions following Endoscopic Transsphenoidal Pituitary Surgery: Improving Quality of Patient Care

Background  Thirty-day unplanned readmission following endoscopic transsphenoidal pituitary surgery (ETPS) occurs in up to 14% of patients. Delayed hyponatremia is one of the most common causes, accounting for 30% of readmissions and often occurs within 1 week of surgery. The authors' prior retrospective review identified endocrinology follow-up as protective factor. Objectives  Implementation of a multidisciplinary postoperative care (POC) pathway: (1) to reduce 30-day hospital readmissions following ETPS and (2) improve inpatient and outpatient coordination of care with endocrinologist. Methods  This study is a single institution temporal cohort study of patients prior to (control cohort) and after implementation of the POC pathway (intervention cohort). The POC pathway utilized postdischarge 1 to 1.5 L/d fluid restriction, postoperative days 5 to 7 serum sodium, and endocrinology follow-up within 1 week of discharge to stratify patients into tiered hyponatremia regimens. Results  A total of 542 patients were included in the study, 409 (75%) in the control cohort and 133 (25%) in the intervention cohort. All-cause readmission was significantly reduced following implementation of the POC pathway (14 vs. 6%, p  = 0.015). Coordination with endocrinologist significantly increased in the inpatient (96 vs. 83%, p  < 0.001) and outpatient (77 vs. 68%, p  = 0.042) settings. Patients who were not in the POC pathway had the highest risk of readmission (odds ratio: 2.5; 95% confidence interval: 1.1-5.5). Conclusion  A multidisciplinary POC pathway incorporating endocrinologist in conjunction with postdischarge weight-based fluid restriction and postoperative serum sodium levels can safely be used to reduce 30-day readmissions following ETPS.

Concurrent intraventricular intracranial myxoid mesenchymal tumor and ependymoma in a long-term Ewing sarcoma survivor

Intracranial myxoid mesenchymal tumor, FET::CREB fusion positive is a rare, recently described central nervous system neoplasm. It is characterized by EWSR1::CREB family transcription factor fusion, typically arises in children and adolescents, and is locally aggressive even after gross total resection. Currently, there are little data available to guide management and gauge long-term prognosis. Furthermore, there have been no reports of these lesions occurring simultaneously with other intracranial neoplasms or in patients with a history of malignancy. Here we describe the first case of a very unusual patient with intracranial myxoid mesenchymal tumor of the right lateral ventricle with a concurrent fourth ventricular ependymoma who had a remote history of Ewing sarcoma of the right fibula.

Survival and Yield of Surveillance Imaging in Long-Term Survivors of Brain Metastasis Treated with Stereotactic Radiosurgery

OBJECTIVES

The optimal frequency of surveillance brain magnetic resonance imaging (MRI) in long-term survivors with brain metastases after stereotactic radiosurgery (SRS) is unknown. Our aim was to identify the optimal frequency of surveillance imaging in long-term survivors with brain metastases after SRS.

METHODS

Eligible patients were identified from a cohort treated with SRS definitively or postoperatively at our institution from 2014 to 2019 with no central nervous system (CNS) failure within 12 months from SRS. Time to CNS disease failure diagnosis and cost per patient were estimated using theoretical MRI schedules of 2, 3, 4, and 6 months starting 1 year after SRS until CNS failure. Time to diagnosis was calculated from the date of CNS progression to the theoretical imaging date on each schedule.

RESULTS

This cohort included 55 patients (median follow-up from SRS: 2.48 years). During the study period, 20.0% had CNS disease failure (median: 2.26 years from SRS treatment). In this cohort, a theoretical 2-month, 3-month, 4-month, and 6-month MRI brain surveillance schedule produced a respective estimated time to diagnosis of CNS disease failure of 1.11, 1.74, 1.65, and 3.65 months. The cost of expedited diagnosis for the cohort (dollars/month) for each theoretical imaging schedule compared with a 6-month surveillance schedule was $6600 for a 2-month protocol, $4496 for a 3-month protocol, and $2180 for a 4-month protocol.

CONCLUSIONS

Based on cost-benefit, a 4-month MRI brain schedule should be considered in patients with metastatic disease to the brain treated definitively or postoperatively with SRS without evidence of CNS recurrence at 1 year.

Brain Metastasis from Pancreatic Cancer: Our Experience and Systematic Review

OBJECTIVE

To systematically review existing literature on the neurosurgical management and outcomes of brain metastasis from pancreatic cancer in comparison with our institutional experience of this patient cohort.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic literature review was performed using PubMed, Ovid Embase, Scopus, and Web of Science databases from date of database inception to March 2022. Studies were selected based on predetermined inclusion and exclusion criteria. Simultaneously, a retrospective analysis was conducted of patients who underwent neurosurgical evaluation and treatment for intracranial metastatic lesions from pancreatic origin at a single institution.

RESULTS

The original literature search yielded 292 articles, of which 17 studies comprising 23 patients with brain metastases of pancreatic origin were ultimately selected. Median overall survival from primary diagnosis of pancreatic cancer was 22 months (interquartile range: 3-84) and 3 months (interquartile range: 1-36) after diagnosis of brain metastasis. In our institutional cohort, 4 patients were identified with a median overall survival of 30.5 months (interquartile range: 2-108). Our institutional cohort experienced a prolonged median overall survival (3 months vs. 30.5 months, P = 0.03) compared with the literature.

CONCLUSIONS

Brain metastasis from pancreatic cancer is rare and associated with a fatal outcome. However, based on the data presented in this review, patient-specific and treatment-related factors could signal better prognosis. Further studies are needed to elucidate multimodal therapy and survival to suggest a more personalized decision-making process.