Retraction Note to: Cerebrospinal fluid ferritin in glioblastoma: evidence for tumor synthesis The Editor-in-Chief has retracted this article [1]. An investigation by Kurume University has not been able to establish what the appropriate authorship should be because one of the authors, Yoshihiro Sato, is now deceased. As the appropriate authorship cannot be determined the Editor-in-Chief no longer has confidence in this article. Kurume University has also stated that it has not been possible to verify the data presented as none of the research material is available for investigation. We have not been able to contact Yoshiaki Honda, Takeshi Asoh, Kotaro Oizumi, Yuki Ohshima and Eiichiro Honda about this retraction.

Correction to: Incidental intracranial meningiomas: a systematic review and meta-analysis of prognostic factors and outcomes Issues with data analysis have recently been highlighted by a reader of our article. These have been addressed with changes to Tables 2&4, as shown below, and Online Resources 5-7. T2 and peritumoral signal are no longer prognostic factors on simple pooled (Online Resource 5) and IPD (Table 4) analyses respectively. In Table 5, the number of patients which informed the outcomes symptom development and intervention were 575 and 947 respectively; 69 developed symptoms (pooled proportion %8.4 [95% CI 2.8-16.7], I2 = 88.9%). These included motor and cognitive deficits (n = 1). We apologise to the readership of the Journal of Neuro-Oncology for these errors and thank the reader for helping us identify them.

Evidence-based dexamethasone dosing in malignant brain tumors: what do we really know? Abstract Purpose The present study aims to conduct a systematic review of literature reporting on the dose and dosing schedule of dexamethasone (DXM) in relation to clinical outcomes in malignant brain tumor patients, with particular attention to evidence-based practice. Methods A systematic search was performed in PubMed, Embase, Web of Science, Cochrane, Academic Search Premier, and PsycINFO to identify studies that reported edema volume reduction, symptomatic relief, adverse events and survival in relation to dexamethasone dose in glioma or brain metastasis (BM) patients. Results After screening 1812 studies, fifteen articles were included for qualitative review. Most studies reported a dose of 16 mg, mostly in a schedule of 4 mg four times a day. Due to heterogeneity of studies, it was not possible to perform quantitative meta-analysis. For BMs, best available evidence suggests that higher doses of DXM may give more adverse events, but may not necessarily result in better clinical condition. Some studies suggest that higher DXM doses are associated with shorter survival in the palliative setting. For glioma, DXM may lead to symptomatic improvement, yet no studies directly compare different doses. Results regarding edema reduction and survival in glioma patients are conflicting. Conclusions Evidence on the safety and efficacy of different DXM doses in malignant brain tumor patients is scarce and conflicting. Best available evidence suggests that low DXM doses may be noninferior to higher doses in certain circumstances, but more comparative research in this area is direly needed, especially in light of the increasing importance of immunotherapy for brain tumors.

Multidimensional assessment of fatigue in patients with brain metastases before and after Gamma Knife radiosurgery Abstract Purpose Fatigue is a common and distressing symptom in cancer patients which negatively affects patients’ daily functioning and health-related quality of life. The aim of this study was to assess multidimensional fatigue in patients with brain metastases (BM) before, and after Gamma Knife radiosurgery (GKRS). Methods Patients with BM, an expected survival > 3 months, and a Karnofsky Performance Status ≥ 70 and 104 Dutch non-cancer controls were recruited. The Multidimensional Fatigue Inventory (MFI), measuring general fatigue, physical fatigue, mental fatigue, reduced activity and reduced motivation, was used. Baseline levels of fatigue between patients and controls were compared using independent-samples t-tests. The course of fatigue over time, and clinical and psychological predictors thereof, were analyzed using linear mixed models (within-group analyses). Results Ninety-two, 67 and 53 patients completed the MFI at baseline, and 3 and 6 months after GKRS. Before GKRS, patients with BM experienced significantly higher levels of fatigue on all subscales compared to controls (medium to large effect sizes). Over 6 months, general and physical fatigue increased significantly (p = .009 and p < .001), and levels of mental fatigue decreased significantly (p = .027). No significant predictors of the course of fatigue over time could be identified. Conclusions Fatigue is a major problem for patients with BM. Different patterns over time were observed for the various aspects of fatigue in patients with BM. Information on the various aspects of fatigue is important because fatigue may negatively affect patients' functional independence, health-related quality of life, and adherence to therapy.

MPC1 deletion is associated with poor prognosis and temozolomide resistance in glioblastoma Abstract Object Mitochondrial pyruvate carrier (MPC) proteins MPC1 and MPC2 form a transporter complex to control rate-limiting pyruvate transportation through the inner mitochondrial membrane. MPC1 plays a crucial role in the tumor metabolite and biosynthesis process. However, the role of MPC1 in glioblastoma (GBM) is unknown. Methods The Cancer Genome Atlas (TCGA) data set, which included 631 cases of GBM with genomic and clinical data, was obtained from the UCSC Xena browser. The clinical data set contained demographic, survival rate, and histological and pathological information. The association between MPC1 gene copy number segments and GBM patient overall survival was analyzed by Kaplan–Meier survival analysis, which was performed using the R2 web-based platform to identify the best cut-off. GraphPad Prism 7 was used to compare the differences in MPC1 gene copy number segments between various groups and subtypes. Results A total of 631 patients with glioblastoma (mean age 57.78 ± 14.36 years, 59% of males) were examined in this study, including 438 cases with MPC1 intact (MPC1 copy number segments > − 0.1, 69.4%) and 157 cases with MPC1 deletion (24.9%) tumors. Among the four GBM subtypes, the proneural group had the highest MPC1 copy number segments and GBM patients diagnosed with proneural subtype showed the best outcome. The expression of MPC1 transcripts was different in the TCGA-GBM dataset compared with the GTEx dataset. MPC1 copy number segments showed a significant correlation with MGMT copy number segments (r = 0.1322, p = 0.0012). MGMT gene expression level in MPC1 intact tumors was significantly lower than that in MPC1 deletion tumors (p = 0.0003). Significant relevancy was observed between better OS and the MPC1 intact group compared with the MPC1 deletion group (p = 0.020). Moreover, patients with MPC1 deletion tumors treated with temozolomide (TMZ) had worse survival than patients with MPC1 intact tumors (p = 0.027). Conclusions Our results suggest a role of decreased MPC1 copy number segments in reducing overall survival in glioblastoma. MPC1 deletion is associated with poor response to TMZ chemotherapy in GBM.

Long-term survival in patients with recurrent glioblastoma treated with bevacizumab: a multicentric retrospective study Abstract Purpose Recurrence of glioblastoma (GB) occurs in most patients after standard concomitant temozolomide-based radiochemotherapy (CTRC). Bevacizumab (BV), an anti-VEGF antibody, has an effect on progression-free survival (PFS) but not on overall survival (OS). However, a small part of the patients experience a survival, longer than expected. This retrospective study aims to characterize long responder (LR) patients treated with BV for a first or second GBM recurrence. Methods Medical records from patients (814) who received BV for a first or second recurrence of primary glioblastoma between September 2010 and September 2015, and initially treated by CTRC were analyzed. Patients, who had at least a stable disease according to RANO criteria at 12 months from the start of BV, were included. Patients who had, a secondary GB, or received BV in neoadjuvant or adjuvant setting were excluded. Results We focused on 65 LR patients without progression 12 months after the first injection of BV (8%). Median PFS was 21.7 months [95% CI (19.3; 27.2)] and median OS was 31.1 months [95% CI (24.3; 37.5)] from the start of BV. No prognostic factor was associated with OS in multivariate analysis. Karnofsky performance status, neurological status and corticosteroid dose were stable at 12 months. Conclusions Our results highlight that among patients receiving bevacizumab in first or second recurrence, one patient out of twelve could be classified as LR. A median OS of 31.1 months from the start of BV could be expected in this subpopulation. These findings reinforce the potential benefit of the use of BV in the situation of recurrence. 256 words

Fractionated stereotactic radiotherapy for local control of resected brain metastases Abstract Purpose Postoperative stereotactic radiosurgery (SRS) has been shown to establish local control in patients with resected brain metastases, yet its efficacy may be limited, particularly for resected lesions with large post-operative resection cavities. We describe the efficacy of postoperative fractionated stereotactic radiotherapy (FSRT) for local control in patients who have undergone resection for brain metastases. Methods In this retrospective cohort study, we analyzed patients who received FSRT for resected brain metastases in 3 or 5 fractions. Time to local recurrence was the primary endpoint in this study. Results Sixty-seven patients (n = 29 female, n = 38 male) met study criteria for review. The median age of the cohort was 62 years (range 18–79 years). Median preoperative tumor volume was 11.1 cm3 (range 0.4–77.0 cm3). The rate of local control was 91.0% at 6 months, 85.1% at 12 months, and 85.1% at 18 months. Estimates of freedom from local recurrence at 6 and 12 months were 90.9% and 84.3%, respectively. Higher biologically equivalent doses (BED10) were found to be predictive of longer freedom from local recurrence on univariate and multivariable analysis. Larger cavity volumes were found to correspond to longer time to local recurrence on univariate and multivariable analysis. Conclusion Our results suggest that postoperative FSRT may be an effective method for providing local control to the surgical bed in patients with resected brain metastases, particularly for larger tumors not amenable to conventional, single-fraction SRS. Additional prospective studies are needed to confirm these findings.

Comparison of ABC/2 estimation and a volumetric computerized method for measurement of meningiomas using magnetic resonance imaging Abstract Introduction Measurement of tumor growth rates over time for patients with meningiomas has important prognostic and therapeutic implications. Our objective was to compare two methods of measuring meningioma volume: (1) the simplified ellipsoid (ABC/2) method; and (2) perimetric volume measurements using imaging software modules. Methods Patients with conservatively managed meningiomas for at least 1.5 years were retrospectively identified from the VCU Brain and Spine Tumor Registry over a 10-year period (2005–2015). Tumor volumes were independently measured using the simplified ellipsoid and computerized perimetric methods. Intra class correlations (CC) and Bland–Altman analyses were performed. Results A total of 26 patients representing 29 tumors were identified. Across 146 images, there were 24 (16%) images that were non-measurable using standard application commands with the computerized perimetric method. The mean volume obtained using the ABC/2 and computerized perimetric methods were 3.2 ± 3.4 cm3 and 3.4 ± 3.5 cm3, respectively. The mean volume difference was 0.2 cm3 (SE = 0.12; p = 0.10) across measurement methods. The concordance correlation coefficient (CCC) between methods was 0.95 (95% CI 0.91, 0.98). Conclusions There is excellent correlation between the simplified ellipsoid and computerized perimetric methods of volumetric analysis for conservatively managed meningiomas. The simplified ellipsoid method remains an excellent method for meningioma volume assessment and had an advantage over the perimetric method which failed to allow measurement of roughly one in six tumors on imaging.

Between-hospital variation in mortality and survival after glioblastoma surgery in the Dutch Quality Registry for Neuro Surgery Abstract Purpose Standards for surgical decisions are unavailable, hence treatment decisions can be personalized, but also introduce variation in treatment and outcome. National registrations seek to monitor healthcare quality. The goal of the study is to measure between-hospital variation in risk-standardized survival outcome after glioblastoma surgery and to explore the association between survival and hospital characteristics in conjunction with patient-related risk factors. Methods Data of 2,409 adults with first-time glioblastoma surgery at 14 hospitals were obtained from a comprehensive, prospective population-based Quality Registry Neuro Surgery in The Netherlands between 2011 and 2014. We compared the observed survival with patient-specific risk-standardized expected early (30-day) mortality and late (2-year) survival, based on age, performance, and treatment year. We analyzed funnel plots, logistic regression and proportional hazards models. Results Overall 30-day mortality was 5.2% and overall 2-year survival was 13.5%. Median survival varied between 4.8 and 14.9 months among hospitals, and biopsy percentages ranged between 16 and 73%. One hospital had lower than expected early mortality, and four hospitals had lower than expected late survival. Higher case volume was related with lower early mortality (P = 0.031). Patient-related risk factors (lower age; better performance; more recent years of treatment) were significantly associated with longer overall survival. Of the hospital characteristics, longer overall survival was associated with lower biopsy percentage (HR 2.09, 1.34–3.26, P = 0.001), and not with academic setting, nor with case volume. Conclusions Hospitals vary more in late survival than early mortality after glioblastoma surgery. Widely varying biopsy percentages indicate treatment variation. Patient-related factors have a stronger association with overall survival than hospital-related factors.

Single-fraction stereotactic radiosurgery for spindle cell oncocytoma: preliminary experience and systematic review of the literature Abstract Purpose Spindle cell oncocytoma (SCO) is a rare benign pituitary tumor. No patient series regarding stereotactic radiosurgery (SRS) for SCO has been published. We report the clinical outcomes of SCO treated with single-fraction SRS, as well as a systematic review of the literature. Methods Retrospective cohort series and systematic literature review. Results Five patients (four male, one female) having single-fraction SRS for persistent or recurrent SCO between 2002 and 2018. Median age was 56 (range 54–79) years. Pre-SRS treatments included transsphenoidal resection (TSR) (n = 3), multiple TSR (n = 1), and TSR, radiotherapy, and craniotomy (n = 1). Median target volume was 4.7 (range 1.8–8.4) cm3, with a median tumor margin dose of 17 (range 14–20) Gy. Median follow-up was 24 (range 10–69) months. All radiation-naïve patients achieved tumor control after SRS; tumor progression was noted 24 months after SRS in one patient who failed prior radiotherapy. No radiation-induced complications were observed after SRS. Systematic literature review of 43 cases in addition to the five cases presented here showed that tumor progression/recurrence was more frequent after STR compared to GTR (P < 0.001). Ten previous cases of radiotherapy for SCO have been reported, but most did not detail radiation volumes, doses, or outcomes. Conclusions SCO are uncommon sellar lesions with a propensity for progression or recurrence. Based on the clinically aggressive course of these tumors, adjuvant SRS after STR or at the time of tumor recurrence should be considered. Further case accumulation and follow-up is required to better understand the long-term treatment outcomes after single-fraction SRS for these rare tumors.