National trends in the treatment of adult diffuse midline gliomas: a rare clinical scenario.

PURPOSE: Diffuse midline gliomas (DMG) include all midline gliomas with a point mutation to the histone H3 gene resulting in the substitution of a lysine with a methionine (K27M). These tumors are classified as World Health Organization grade 4 with a mean survival between 9- and 19-months following diagnosis. There is currently no standard of care for DMG, and palliative radiation therapy has been proven to only extend survival by months. Our current study aims to report current treatment trends and predictors of the overall survival of DMG. METHODS: We searched the National Cancer Database for adult patients treated for DMG from 2016 to 2020. Patients were required to have been treated with primary radiation directed at the brain with or without concurrent chemotherapy. Univariable and multivariable Cox regressions were used to determine predictors of overall survival. RESULTS: Of the 131 patients meeting the inclusion criteria, 113 (86%) received radiation and chemotherapy. Based on multivariable Cox regression, significant predictors of survival were Charlson-Deyo comorbidity index and race. Patients with a Charlson-Deyo score of 1 had 2.72 times higher odds of mortality than those with a score of 0. Patients not identifying as White or Black had 2.67 times higher odds of mortality than those identifying as White. The median survival for all patients was 19 months. CONCLUSIONS: Despite being considered ineffective, chemotherapy is still administered in most adult patients diagnosed with DMG. Significant predictors of survival were Charlson-Deyo comorbidity index and race.

Social media insights for neurosurgical oncologists: a survey of the American Association of Neurological Surgeons and Congress of Neurological Surgeons Joint Section on Tumors.

PURPOSE: There is a paucity in the literature regarding the characteristics and attitudes of social media (SM) utilization in a professional manner by neurosurgical oncologists. METHODS: A 34-question electronic survey was created using Google Forms and disseminated via email to members of the AANS/CNS Joint Section on Tumors. Demographic data were compared amongst those who utilize social media versus those who do not. Factors associated with positive effects of professional SM use and with having more followers on SM were analyzed. RESULTS: The survey received 94 responses, of which 64.9% reported that they currently use SM in a professional manner. Age < 50 years was found to be associated with SM use (p = 0.038). Facebook (54.1%), Twitter (60.7%), Instagram (41%), and LinkedIn (60.7%) were the most used SM platforms. Having a higher number of followers was associated with practicing in academics (p = 0.005), using Twitter (p = 0.013), posting about their own research publications (p = 0.018), posting interesting cases (p = 0.022), and posting about upcoming events (p = 0.001). Having a higher number of followers on SM was also associated with positive effects, specifically new patient referrals (p = 0.04). CONCLUSION: Neurosurgical oncologists can benefit by using social media professionally for increased patient engagement and networking within the medical community. Practicing in academics, making use of Twitter, and posting about interesting cases, upcoming academic events, and one's own research publications can help gain followers. In addition, having a large following on social media could lead to positive effects such as new patient referrals.

Utilization of neoadjuvant stereotactic radiosurgery for the treatment of brain metastases requiring surgical resection: a topic review.

PURPOSE: Following surgical resection of brain metastases (BMs), adjuvant stereotactic radiosurgery (SRS) has become the standard of care post-operative cavity irradiation. Recent studies, however, have demonstrated that with the current sequence of surgery and radiation, risk of leptomeningeal disease (LMD) and radiation necrosis (RN) remains high. Pre-operative, or neoadjuvant, SRS (nSRS) has been proposed as an alternative treatment strategy which not only minimizes local recurrence (LR) but also LMD and RN. It is thought that nSRS sterilizes the tumor, allowing for minimal spillage of viable tumor cells during resection, creating less favorable conditions for LMD. Furthermore, nSRS allows for easier contouring and decreased margin irradiation during planning and treatment, respectively, diminishing the risk of symptomatic RN. While nSRS has already been adopted for treating other extra-cranial tumors, its role in treating BMs is yet to be defined. We aim to summarize recent studies in nSRS usage for BMs and the rationale of this treatment strategy. METHODS: We performed a search for articles regarding nSRS for BMs published in PubMed from 2018 to 2022 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. We summarized a total of 14 retrospective reviews, case series, dose/timing studies, and ongoing Phase II & III clinical trials. CONCLUSION: In this review, we describe the findings of current studies and identify prospective clinical trials with the aim of understanding the efficacy of nSRS over current treatment standards. Herein, we also discuss the theoretical advantages and limitations of nSRS (both biologic and clinical) to help guide future clinical investigations.

Trends in radiation dose for low grade gliomas across the United States.

PURPOSE: Adjuvant radiation is often used in patients with low grade gliomas with high-risk characteristics with a recommended dose of 45-54 Gy. We used the National Cancer Database (NCDB) to see which doses were being used, and if any difference was seen in outcome. METHODS: We queried the NCDB for patients with WHO Grade 2 primary brain tumors treated with surgery and adjuvant radiotherapy. We divided the cohort into dose groups: 45-50 Gy, 50.4-54 Gy, and > 54 Gy. Multivariable logistic regression was used to identify predictors of low and high dose radiation. Propensity matching was used to account for indication bias. RESULTS: We identified 1437 patients meeting inclusion criteria. Median age was 45 years and 62% of patients were > 40 years old. Nearly half of patients (48%) had astrocytoma subtype and 70% had subtotal resection. The majority of patients (69%) were treated to doses between 50.4 and 54 Gy. Predictors of high dose radiation (> 54 Gy) were increased income, astrocytoma subtype, chemotherapy receipt, and treatment in later year (2014). The main predictors of survival were age > 40, astrocytoma subtype, and insurance type. Patients treated to a dose of > 54 Gy had a median survival of 73.5 months and was not reached in those treated to a lower dose (p = 0.0041). CONCLUSIONS: This analysis shows that 50.4-54 Gy is the most widely used radiation regimen for the adjuvant treatment of low-grade gliomas. There appeared to be no benefit to higher doses, although unreported factors may impact interpretation of the results.

Long term outcomes following surgery for pineal region tumors.

PURPOSE: Pineal region tumors are surgically demanding tumors to resect. Long term neuro-oncologic outcomes following surgical excision of tumors from this region have been underreported. We sought to define the long term outcomes of patients undergoing resection of pineal region tumors. METHODS: A retrospective analysis of a prospectively maintained database was performed on patients who underwent intended surgical excision of pineal region tumors. Overall survival (OS) and progression free survival (PFS) were the primary endpoints of this study. Factors associated with OS, PFS and the degree of resection were analyzed, along with 30-day complication rates and dependence on CSF diversion. RESULTS: Sixty-eight patients with a mean age of 30.9 ± 15.3 years were analyzed. The median clinical and radiographic follow-up was 95.7 and 48.2 months, respectively. The supracerebellar infratentorial and the occipital transtentorial corridors were utilized in the majority of cases (80.9%). The gross total resection (GTR) rate was 52.9% (n=36). The 5-year OS and PFS rates were 70.2% and 58.5%, respectively. Achieving GTR was associated with improved OS (HR 0.39, p = 0.03) and PFS (HR 0.4, p = 0.006). The 30-day mortality rate was 5.9%. The need for CSF diversion was high with 77.9% of patients requiring a shunt or ETV by last follow-up. CONCLUSIONS: This is the first modern surgical series providing long term follow-up for patients undergoing surgical resection of pineal region tumors. Obtaining a GTR of these challenging tumors is beneficial with regards to PFS/OS. Higher grade tumors have diminished PFS/OS and are treated with adjuvant chemotherapy and/or radiotherapy.

Whole-exome sequencing of oral mucosal melanoma reveals mutational profile and therapeutic targets.

Oral mucosal melanoma (OMM) is a rare and aggressive subtype of melanoma with little known about its pathogenesis or carcinogenesis. We therefore performed whole-exome sequencing (WES) on 19 matched OMM tumor/normal pairs in order to gain insight into potential genetic drivers of tumor formation. For the first time, we describe the comprehensive mutational profile of OMM. Our data suggest that the genetic background of OMM differs from those of other melanoma subtypes. We identified recurrent mutations involving KIT, POLE, PTPRD, PTCHD2, and DMXL2. Notably, copy number analysis revealed recurrently amplified regions of 12q14 (57.9%, containing CDK4) and 5p15 (47.4%, containing TERT). CNV analysis in a separate cohort of 15 samples validated the frequent CNV in CDK4 and TERT. We also observed that the melanocyte development and pigmentation signaling pathway is frequently altered in OMM. Furthermore, our data suggest several altered genes that may be amenable for targeted therapy. We identified one patient with metastatic OMM in our cohort who was identified to harbor a targetable KIT mutation using our WES results. This patient was able to achieve complete remission following implementation of KIT-targeted therapy. These findings provide further insight into the genetic underpinnings of OMM development and suggest that patients with OMM may benefit from WES analysis to identify potential targetable genetic mutations. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Enhancement of mitochondrial biogenesis and paradoxical inhibition of lactate dehydrogenase mediated by 14-3-3η in oncocytomas.

Oncocytomas represent a subset of benign pituitary adenomas that are characterized by significant mitochondrial hyperplasia. Mitochondria are key organelles for energy generation and metabolic intermediate production for biosynthesis in tumour cells, so understanding the mechanism underlying mitochondrial biogenesis and its impact on cellular metabolism in oncocytoma is vital. Here, we studied surgically resected pituitary oncocytomas by using multi-omic analyses. Whole-exome sequencing did not reveal any nuclear mutations, but identified several somatic mutations of mitochondrial DNA, and dysfunctional respiratory complex I. Metabolomic analysis suggested that oxidative phosphorylation was reduced within individual mitochondria, and that there was no reciprocal increase in glycolytic activity. Interestingly, we found a reduction in the cellular lactate level and reduced expression of lactate dehydrogenase A (LDHA), which contributed to mitochondrial biogenesis in an in vitro cell model. It is of note that the hypoxia-response signalling pathway was not upregulated in pituitary oncocytomas, thereby failing to enhance glycolysis. Proteomic analysis showed that 14-3-3η was exclusively overexpressed in oncocytomas, and that 14-3-3η was capable of inhibiting glycolysis, leading to mitochondrial biogenesis in the presence of rotenone. In particular, 14-3-3η inhibited LDHA by direct interaction in the setting of complex I dysfunction, highlighting the role of 14-3-3η overexpression and inefficient oxidative phosphorylation in oncocytoma mitochondrial biogenesis. These findings deepen our understanding of the metabolic changes that occur within oncocytomas, and shine a light on the mechanism of mitochondrial biogenesis, providing a novel perspective on metabolic adaptation in tumour cells. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Gamma knife radiosurgery for the treatment of gynecologic malignancies metastasizing to the brain: clinical article.

Gynecologic malignancies represent some of the commonest causes of cancer in the female population. Despite their overall high prevalence, gynecologic malignancies have seldom been reported to metastasize to the brain. The incidence of gynecologic cancers spreading to the brain has been rising, and the optimal management of these patients is not well defined. A retrospective analysis of patients treated over the past ten years with gamma knife radiosurgery (GKRS) for metastatic gynecologic cancer to the brain was performed. Radiographic treatment response, tumor control, metastatic disease progression and survival data were analyzed. Eight patients with ovarian cancer, six patients with endometrial cancer and two separates who carried a diagnosis of cervical cancer or leiomyosarcoma harbored metastatic disease to the brain that was treated with GKRS. The median dose to the tumor margin was 20 Gy (range 10-22 Gy), and the median maximum radiosurgical dose was 31 Gy (range 16-52.9 Gy). Tumor control was achieved in all patients who had follow up imaging studies. Patients with ovarian cancer had prolonged median survival following GKRS compared to patients with endometrial cancer (22.3 vs 8.3 months, p = 0.02). The patient with cervical cancer survived 8 months following her GKRS in the setting of metastatic brain tumor progression, whereas the patient with leiomyosarcoma passed away within several weeks of treatment secondary to disseminated extracranial primary disease. GKRS is a safe and effective means of achieving intracranial tumor control for patients with gynecologic cancer that has spread to the brain.

Lateral retroperitoneal transpsoas approach to the lumbar spine for the treatment of spondylodiscitis.

Spondylodiscitis is an infection of the intervertebral disc and adjacent vertebrae. With the advent of minimally invasive spinal surgery, less invasive approaches have been considered for the treatment of discitis. To date, however, there have been no reported cases of a minimally invasive lateral retroperitoneal transpsoas approach for the treatment of spondylodiscitis. The authors report a case of medically refractory discitis in a patient with multiple comorbidities who underwent a successful limited debridement via a lateral transpsoas corridor. This case describes a minimally invasive approach used to treat a patient with lumbar discitis/osteomyelitis who was otherwise a suboptimal surgical candidate.

Cost of Treatment for Brain Metastases Using Data From a National Health Insurance.

Purpose: In the United States, brain metastases (BMs) affect 10% to 20% of patients with cancer, presenting a significant health care challenge and necessitating intricate, high-cost treatments. Few studies have explored the comprehensive care cost for BMs, and none have used real insurance claims data. Partnering with a northeastern health care insurer, we investigated the true costs of various brain-directed radiation methods, aiming to shed light on treatment expenses, modalities, and their efficacy. Methods and Materials: We analyzed medical claims from Highmark Health-insured patients in Pennsylvania, Delware, West Virginia, and New York diagnosed with BMs (ICD-10 code C79.31) and treated with radiation from January 1, 2020 to July 1, 2022. Costs for radiation techniques were grouped by specific current procedural terminology claim codes. We subdivided costs into technical and physician components and separated hospital from freestanding costs for some modalities. Results: From January 1, 2020 to July 1, 2022, 1048 Highmark Health members underwent treatment for BMs. Females (n = 592) significantly outnumbered males (n = 456), with an average age of 64.4 years. Each member had, on average, 5.309 claims costing $2015 per claim. Total cost totaled $10,697,749. Per-treatment analysis showed that hippocampal avoidance intensity modulated radiation therapy was the costliest treatment at $47,748, followed by stereotactic radiation therapy at $37,230, linear accelerator stereotactic radiosurgery (SRS) at $30,737, Gamma Knife SRS at $30,711, and whole-brain radiation therapy at $5225. Conclusions: Whole-brain radiation therapy was the least costly radiation technique. Similar per-treatment prices for Gamma Knife and linear accelerator SRS support their use in treating BMs. Stereotactic radiation therapy in general was costlier on a per-use basis than SRS, prompting further scrutiny on its frequent use. Hippocampal avoidance intensity modulated radiation therapy was the costliest radiation therapy on a per-use basis by a moderate amount, prompting further discussion about its comparative cost effectiveness against other radiation modalities. This study underscores the importance of multiple considerations in treating BMs, such as tumor control, survival, side effects, and costs.

The 5-factor modified frailty index as a prognostic factor of stereotactic radiosurgery for metastatic disease to the brain.

OBJECTIVE: Frailty, a state of increased vulnerability to adverse health outcomes, is associated with poor neurosurgical outcomes. The relationship between frailty and stereotactic radiosurgery (SRS) for brain metastases (BMs), however, has not been adequately described. In this study, the authors attempted to examine the connection between frailty and outcomes for patients receiving SRS for BMs. METHODS: A single-center retrospective cohort study was performed. The 5-factor modified frailty index (mFI-5) was used to stratify patients into pre-frail (mFI-5 score 0-1), frail (mFI-5 score 2), and severely frail (mFI-5 score ≥ 3) cohorts at the time of SRS treatment. Both overall survival (OS) and progression-free survival (PFS) were evaluated. Factors associated with OS/PFS were assessed using Kaplan-Meier analysis and a Cox proportional hazards model. RESULTS: Two hundred three patients met the inclusion criteria and received SRS to one or more BMs. Fifty-six patients (27.6%) received SRS as an adjuvant treatment. The 12-month OS and PFS rates were 58.6% and 45.5%, respectively. One hundred twenty-six patients (62.1%) were classified as pre-frail, 58 (28.6%) as frail, and 19 (9.4%) as severely frail. Significantly less OS was demonstrated in frailer groups (frail hazard ratio [HR] 3.14, p < 0.005; severely frail HR 3.13, p < 0.005). Compared with pre-frail patients, frail patients had shorter intervals of PFS (frail HR 2.05, p < 0.005). Five patients (2.5%) had symptomatic radiation necrosis (RN) and 60 (29.6%) required repeat radiation. CONCLUSIONS: Higher frailty scores at the time of SRS treatment were predictive of shorter OS and PFS intervals.

Occipital-interhemispheric transtentorial pineal mass resection.

The occipital approach for pineal tumors was first described by James Poppen in 1966. Since then, it has been widely used for accessing deep-seated tumors as it offers a wider surgical view than the supracerebellar transtentorial approach. This video demonstrates the technical nuances of the occipital transtentorial approach and the exoscopic dissection of a pineal gland tumor in a 66-year-old male. Use of the exoscope over the microscope provides certain ergonomic advantages and improves surgical workflow, as demonstrated here. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23161.

Intratumoral Hemorrhage in Vestibular Schwannomas After Stereotactic Radiosurgery: Multi-Institutional Study.

BACKGROUND AND OBJECTIVES: Intratumoral hemorrhage (ITH) in vestibular schwannoma (VS) after stereotactic radiosurgery (SRS) is exceedingly rare. The aim of this study was to define its incidence and describe its management and outcomes in this subset of patients. METHODS: A retrospective multi-institutional study was conducted, screening 9565 patients with VS managed with SRS at 10 centers affiliated with the International Radiosurgery Research Foundation. RESULTS: A total of 25 patients developed ITH (cumulative incidence of 0.26%) after SRS management, with a median ITH size of 1.2 cm 3 . Most of the patients had Koos grade II-IV VS, and the median age was 62 years. After ITH development, 21 patients were observed, 2 had urgent surgical intervention, and 2 were initially observed and had late resection because of delayed hemorrhagic expansion and/or clinical deterioration. The histopathology of the resected tumors showed typical, benign VS histology without sclerosis, along with chronic inflammatory cells and multiple fragments of hemorrhage. At the last follow-up, 17 patients improved and 8 remained clinically stable. CONCLUSION: ITH after SRS for VS is extremely rare but has various clinical manifestations and severity. The management paradigm should be individualized based on patient-specific factors, rapidity of clinical and/or radiographic progression, ITH expansion, and overall patient condition.

Stereotactic radiosurgery for nonfunctioning pituitary tumor: A multicenter study of new pituitary hormone deficiency.

BACKGROUND: Stereotactic radiosurgery (SRS) is used to treat recurrent or residual nonfunctioning pituitary neuroendocrine tumors (NFPA). The objective of the study was to assess imaging and development of new pituitary hormone deficiency. METHODS: Patients treated with single-session SRS for a NFPA were included in this retrospective, multicenter study. Tumor control and new pituitary dysfunction were evaluated using Cox analysis and Kaplan-Meier curves. RESULTS: A total of 869 patients (male 476 [54.8%], median age at SRS 52.5 years [Interquartile range (IQR): 18.9]) were treated using a median margin dose of 14Gy (IQR: 4) for a median tumor volume of 3.4 cc (IQR: 4.3). With a median radiological follow-up of 3.7 years (IQR: 4.8), volumetric tumor reduction occurred in 451 patients (51.9%), stability in 364 (41.9%) and 54 patients (6.2%) showed tumor progression.The probability of tumor control was 95.5% (95% Confidence Interval [CI]: 93.8-97.3) and 88.8% (95%CI: 85.2-92.5) at 5 and 10 years, respectively. A margin dose >14 Gy was associated with tumor control (Hazard Ratio [HR]:0.33, 95% CI: 0.18-0.60, P < 0.001). The probability of new hypopituitarism was 9.9% (95% CI: 7.3-12.5) and 15.3% (95% CI: 11-19.4) at 5 and 10 years, respectively. A maximum point dose >10 Gy in the pituitary stalk was associated with new pituitary hormone deficiency (HR: 3.47, 95% CI: 1.95-6.19). The cumulative probability of new cortisol, thyroid, gonadotroph, and growth hormone deficiency was 8% (95% CI: 3.9-11.9), 8.3% (95% CI: 3.9-12.5), 3.5% (95% CI: 1.7-5.2), and 4.7% (95% CI: 1.9-7.4), respectively at 10 years. CONCLUSIONS: SRS provides long-term tumor control with a 15.3% risk of hypopituitarism at 10 years.