Association of extent of resection and functional outcomes in diffuse low-grade glioma: systematic review & meta-analysis.

BACKGROUND: Surgical resection offers survival benefits in patients with diffuse low-grade glioma (DLGG) but its association with functional outcomes is uncertain. This systematic review assessed functional outcomes associated with extent of resection (EoR) in adults with DLGG. METHODS: We searched Medline, Embase and CENTRAL on the 19th of February 2021 for observational studies reporting functional outcomes after surgical resection for patients aged ≥ 18 years with a new diagnosis of supratentorial DLGG according to any World Health Organization classification of primary brain tumors. The Newcastle-Ottawa Scale (NOS) informed our risk of bias assessments. The proportion of patients returning to work within 12 months entered a random-effects meta-analysis. PROSPERO registration number CRD42021238387. RESULTS: There were seven eligible moderate to high-quality (NOS > 6) observational studies identified from 1,183 records involving 234 patients with DLGG. Functional outcomes reported included neurocognition (n = 2 studies), performance status (n = 3), quality of life (QoL) (n = 1) and return to work (n = 6). The proportion of patients who returned to work within 12 months of surgery was 84% (95% confidence interval [CI] 50-96%, I-squared = 38%, 5 studies) for gross total resection, 66% (95% CI 14-96%, I2 = 57%, 5 studies) for subtotal resection, and 31% (95% CI 4-82%, I2 = 0%, 4 studies) for partial resection. There was insufficient data on other functional outcomes for quantitative synthesis. CONCLUSION: A higher proportion of DLGG patients returned to work following gross total resection compared with those who had a subtotal or partial resection. Further studies with standardized assessments can clarify the association between EoR and different functional outcomes.

Drains result in greater reduction of subdural width and midline shift in burr hole evacuation of chronic subdural haematoma.

BACKGROUND: Drain insertion following chronic subdural haematoma (CSDH) evacuation reduces recurrence and improves outcomes. The mechanism of this improvement is uncertain. We assessed whether drains result in improved postoperative imaging, and which radiological factors are associated with recurrence and functional outcome. METHODS: A multi-centre, prospective cohort study of CSDH patients was performed between May 2013 and January 2014. Patients aged > 16 years undergoing burr hole evacuation of primary CSDH with pre- and postoperative imaging were included in this subgroup analysis. Baseline and clinical details were collected. Pre- and postoperative maximal subdural width and midline shift (MLS) along with clot density were recorded. Primary outcomes comprised mRS at discharge and symptomatic recurrence requiring re-drainage. Comparisons were made using multiple logistic regression. RESULTS: Three hundred nineteen patients were identified for inclusion. Two hundred seventy-two of 319 (85%) patients underwent drain insertion at the time of surgery versus 45/319 (14%) who did not. Twenty-nine of 272 patients who underwent drain insertion experienced recurrence (10.9%) versus 9 of 45 patients without drain insertion (20.5%; p = 0.07). Overall change in median subdural width was significantly greater in the drain versus 'no drain' groups (11 mm versus 6 mm, p < 0.01). Overall change in median midline shift (MLS) was also significantly greater in the drain group (4 mm versus 3 mm, p < 0.01). On multivariate analysis, change in maximal width and MLS were significant predictors of recurrence, although only the former remained a significant predictor for functional outcome. CONCLUSIONS: The use of subdural drains results in significantly improved postoperative imaging in burr hole evacuation of CSDH, thus providing radiological corroboration for their recommended use.

Prospective, multicentre study of external ventricular drainage-related infections in the UK and Ireland.

OBJECTIVES: External ventricular drain (EVD) insertion is a common neurosurgical procedure. EVD-related infection (ERI) is a major complication that can lead to morbidity and mortality. In this study, we aimed to establish a national ERI rate in the UK and Ireland and determine key factors influencing the infection risk. METHODS: A prospective multicentre cohort study of EVD insertions in 21 neurosurgical units was performed over 6 months. The primary outcome measure was 30-day ERI. A Cox regression model was used for multivariate analysis to calculate HR. RESULTS: A total of 495 EVD catheters were inserted into 452 patients with EVDs remaining in situ for 4700 days (median 8 days; IQR 4-13). Of the catheters inserted, 188 (38%) were antibiotic-impregnated, 161 (32.5%) were plain and 146 (29.5%) were silver-bearing. A total of 46 ERIs occurred giving an infection risk of 9.3%. Cox regression analysis demonstrated that factors independently associated with increased infection risk included duration of EVD placement for ≥8 days (HR=2.47 (1.12-5.45); p=0.03), regular sampling (daily sampling (HR=4.73 (1.28-17.42), p=0.02) and alternate day sampling (HR=5.28 (2.25-12.38); p<0.01). There was no association between catheter type or tunnelling distance and ERI. CONCLUSIONS: In the UK and Ireland, the ERI rate was 9.3% during the study period. The study demonstrated that EVDs left in situ for ≥8 days and those sampled more frequently were associated with a higher risk of infection. Importantly, the study showed no significant difference in ERI risk between different catheter types.

Long-term prognosis after intracerebral haemorrhage: systematic review and meta-analysis.

BACKGROUND AND AIM: There is uncertainty about the long-term prognosis after spontaneous intracerebral haemorrhage (ICH). Therefore, we systematically reviewed the literature for studies reporting long-term survival and ICH recurrence, and their predictors. METHODS: We searched Ovid Medline 1946-2011 inclusive for cohort studies of ≥50 patients reporting long-term (>30 days) outcome after ICH. Two reviewers independently extracted data from each study. We meta-analysed 1-year and 5-year survival data from population-based studies using a random effects model (and quantified inconsistency using the I2 statistic). RESULTS: We identified 122 eligible studies. The pooled estimate of 1-year survival was 46% (95% CI 43% to 49%; nine population-based studies (n=2408); I2=27%) and 5-year survival was 29% (95% CI 26% to 33%; three population-based studies (n=699); I2=6%). In 27 cohort studies, predictors most consistently associated with death were increasing age, decreasing Glasgow Coma Scale score, increasing ICH volume, presence of intraventricular haemorrhage, and deep/infratentorial ICH location. The annual risk of recurrent ICH varied from 1.3% to 7.4% in nine studies and this risk was higher after lobar ICH than non-lobar ICH in two of three hospital-based studies. Four studies reporting the risks of recurrent ICH and ischaemic stroke after ICH found no significant differences between these risks. CONCLUSIONS: Less than a half of patients with ICH survive 1 year and less than a third survive 5 years. Risks of recurrent ICH and ischaemic stroke after ICH appear similar after ICH, provoking uncertainties about the use of antithrombotic drugs.

Outcome of elderly patients undergoing intracranial meningioma resection--a systematic review and meta-analysis.

BACKGROUND: Intracranial meningioma is a common condition in the elderly population. Surgical resection in this group of patients may be rendered more hazardous due to the patients' ageing physiology and to multiple comorbidities. This systematic review and meta-analysis aimed to summarise outcome data of elderly patients undergoing intracranial meningioma resection. METHODS: Using Ovid Medline, longitudinal studies published from 2002 to October 2012 with patients aged ≥ 65 years that described outcomes after intracranial meningioma resection were reviewed. Outcome data included mortality, recurrence, complication rate and length of hospital stay (LoS). Grading score systems and covariates for predicting outcome were collected. Pooled estimates of mortality data were calculated in StatsDirect using a random effects method. I(2) statistic was used to assess heterogeneity. RESULTS: Thirteen eligible studies with a total of 7010 patients (mean age, 73.6 years) were included, in which 82% patients came from one study. The pooled estimates of 90-day and 1-year mortality from available data were 6.6% (95% confidence interval [CI], 4.6-9.1%; n = 735; I(2) = 32.1) and 9.6% (95% CI, 7.0-12.6%; n = 564; I(2) = 24.3), respectively. The overall complication rates ranged from 2.7% to 29.8%, and the overall incidence of complications was 20% per patient (range, 3-61%). Other outcome data were heterogeneous mainly due to incomparable study designs. CONCLUSIONS: Current evidence indicates satisfactory surgical outcomes in the elderly with intracranial meningiomas, though the risks of complications necessitate careful consideration when deciding to operate. Risk factor analysis emphasised the importance of considering pre-operative status and comorbidities during patient selection. Future research should address the causes and prevention of complications, and compare outcomes between younger and older patients using detailed stratifications of tumour characteristics.

Outcome comparison between younger and older patients undergoing intracranial meningioma resections.

Studies directly comparing the outcomes of intracranial meningioma resection between elderly and younger patients are currently limited. This study aimed to assess the perioperative complications, mortalities and functional outcomes in these two groups. Consecutive elderly patients (aged ≥ 65) and tumor-location-matched younger patients who underwent intracranial meningioma resections were retrospectively reviewed. Outcomes were assessed at 30-day, 90-day, 6-month and 1-year. We used a standardized classification of operative complications, and conducted subgroup analyses based on tumor location [convexity, parasagittal and falcine (CPF) as one group; skull base (SB) as another]. There were 92 patients in each group. The mean age was 74.6 ± 6.4 years in the elderly and 49.3 ± 10.1 years in the younger groups. The cumulative 30-day, 90-day and 1-year mortality rates were 0, 2.2 and 4.3 % for the elderly, respectively, and 1.1 % for all time points in the young. These differences were not statistically significant. Overall, the elderly suffered from more perioperative complications (P = 0.010), and these were mostly minor complications according to the classification of operative complications. However, these differences were observed only in the SB but not in the CPF subgroup. More elderly patients had impaired functional outcome 1-year after surgery. Significantly more elderly patients had new neurological deficits 1-year after surgery (26.1 vs. 6.6 %; P = 0.001). Comparable mortality rates were observed in elderly and younger patients. However, the elderly had more minor complications and poorer functional outcomes. Patient selection remains key to good clinical outcome.

Analytic approaches to clinical validation of results from preclinical models of glioblastoma: A systematic review.

INTRODUCTION: Analytic approaches to clinical validation of results from preclinical models are important in assessment of their relevance to human disease. This systematic review examined consistency in reporting of glioblastoma cohorts from The Cancer Genome Atlas (TCGA) or Chinese Glioma Genome Atlas (CGGA) and assessed whether studies included patient characteristics in their survival analyses. METHODS: We searched Embase and Medline on 02Feb21 for studies using preclinical models of glioblastoma published after Jan2008 that used data from TCGA or CGGA to validate the association between at least one molecular marker and overall survival in adult patients with glioblastoma. Main data items included cohort characteristics, statistical significance of the survival analysis, and model covariates. RESULTS: There were 58 eligible studies from 1,751 non-duplicate records investigating 126 individual molecular markers. In 14 studies published between 2017 and 2020 using TCGA RNA microarray data that should have the same cohort, the median number of patients was 464.5 (interquartile range 220.5-525). Of the 15 molecular markers that underwent more than one univariable or multivariable survival analyses, five had discrepancies between studies. Covariates used in the 17 studies that used multivariable survival analyses were age (76.5%), pre-operative functional status (35.3%), sex (29.4%) MGMT promoter methylation (29.4%), radiotherapy (23.5%), chemotherapy (17.6%), IDH mutation (17.6%) and extent of resection (5.9%). CONCLUSION: Preclinical glioblastoma studies that used TCGA for validation did not provide sufficient information about their cohort selection and there were inconsistent results. Transparency in reporting and the use of analytic approaches that adjust for clinical variables can improve the reproducibility between studies.

Might changes in diagnostic practice explain increasing incidence of brain and central nervous system tumors? A population-based study in Wales (United Kingdom) and the United States.

BACKGROUND: Increasing incidence of central nervous system (CNS) tumors has been noted in some populations. However, the influence of changing surgical and imaging practices has not been consistently accounted for. METHODS: We evaluated average annual percentage change (AAPC) in age- and gender-stratified incidence of CNS tumors by tumor subtypes and histological confirmation in Wales, United Kingdom (1997-2015) and the United States (2004-2015) using joinpoint regression. FINDINGS: In Wales, the incidence of histologically confirmed CNS tumors increased more than all CNS tumors (AAPC 3.62% vs 1.63%), indicating an increasing proportion undergoing surgery. Grade II and III glioma incidence declined significantly (AAPC -3.09% and -1.85%, respectively) but remained stable for those with histological confirmation. Grade IV glioma incidence increased overall (AAPC 3.99%), more markedly for those with histological confirmation (AAPC 5.36%), suggesting reduced glioma subtype misclassification due to increased surgery. In the United States, the incidence of CNS tumors increased overall but was stable for histologically confirmed tumors (AAPC 1.86% vs 0.09%) indicating an increase in patients diagnosed without surgery. An increase in grade IV gliomas (AAPC 0.28%) and a decline in grade II gliomas (AAPC -3.41%) were accompanied by similar changes in those with histological confirmation, indicating the overall trends in glioma subtypes were unlikely to be caused by changing diagnostic and clinical management. CONCLUSIONS: Changes in clinical practice have influenced the incidence of CNS tumors in the United Kingdom and the United States. These should be considered when evaluating trends and in epidemiological studies of putative risk factors for CNS tumors.

Does Drain Position and Duration Influence Outcomes in Patients Undergoing Burr-Hole Evacuation of Chronic Subdural Hematoma? Lessons from a UK Multicenter Prospective Cohort Study.

BACKGROUND: Drain insertion following chronic subdural hematoma (CSDH) evacuation improves patient outcomes. OBJECTIVE: To examine whether this is influenced by variation in drain location, positioning or duration of placement. METHODS: We performed a subgroup analysis of a previously reported multicenter, prospective cohort study of CSDH patients performed between May 2013 and January 2014. Data were analyzed relating drain location (subdural or subgaleal), position (through a frontal or parietal burr hole), and duration of insertion, to outcomes in patients aged >16 yr undergoing burr-hole drainage of primary CSDH. Primary outcomes comprised modified Rankin scale (mRS) at discharge and symptomatic recurrence requiring redrainage within 60 d. RESULTS: A total of 577 patients were analyzed. The recurrence rate of 6.7% (12/160) in the frontal subdural drain group was comparable to 8.8% (30/343) in the parietal subdural drain group. Only 44/577 (7.6%) patients underwent subgaleal drain insertion. Recurrence rates were comparable between subdural (7.7%; 41/533) and subgaleal (9.1%; 4/44) groups (P = .95). We found no significant differences in discharge mRS between these groups. Recurrence rates were comparable between patients with postoperative drainage for 1 or 2 d, 6.4% and 8.4%, respectively (P = .44). There was no significant difference in mRS scores between these 2 groups (P = .56). CONCLUSION: Drain insertion after CSDH drainage is important, but position (subgaleal or subdural) and duration did not appear to influence recurrence rate or clinical outcomes. Similarly, drain location did not influence recurrence rate nor outcomes where both parietal and frontal burr holes were made. Further prospective cohort studies or randomized controlled trials could provide further clarification.