Association Between Perioperative Hyperglycemia and Survival in Patients With Glioblastoma

Dexamethasone in Patients with Glioblastoma: A Systematic Review and Meta-Analysis

OBJECTIVE

Glioblastomas are the most common primary central nervous system (CNS) tumors. Although modern management strategies have modestly improved overall survival, the prognosis remains dismal, with treatment side effects often impinging on the clinical course. Glioblastomas cause neurological dysfunction by infiltrating CNS tissue and via perifocal oedema formation. The administration of steroids such as dexamethasone is thought to alleviate symptoms by reducing oedema. However, despite its widespread use, the evidence for the administration of dexamethasone is limited and conflicting. Therefore, we aimed to review the current evidence concerning the use and outcomes of dexamethasone in patients with glioblastoma.

METHODS

We performed a systematic review and meta-analysis according to the PRISMA-P guidelines. We performed a restricted search using the keywords "Dexamethasone" and "Glioblastoma" on PubMed, Web of Science, Cochrane Library, and Academic Search Premier. We included studies reporting on overall survival (OS) and progression-free survival (PFS) in glioblastoma patients receiving higher or lower dexamethasone doses. The risk of bias was assessed using ROBINS-I. We performed a meta-analysis using a random effects model for OS and PFS.

RESULTS

Twenty-two retrospective studies were included. Higher doses of dexamethasone were associated with poorer OS (hazard ratio 1.62, confidence interval 1.40-1.88) and PFS (1.49, 1.23-1.81). OS remained worse even when studies corrected for clinical status (1.52, 1.38-1.67).

CONCLUSION

Despite the widespread use of dexamethasone in glioblastoma patients, its use is correlated with worse long-term outcomes. Consequently, Dexamethasone administration should be restricted to selected symptomatic patients. Future prospective studies are crucial to confirm these findings.

The need for paradigm shift: prognostic significance and implications of standard therapy-related systemic immunosuppression in glioblastoma for immunotherapy and oncolytic virotherapy

Despite significant advances in our knowledge regarding the genetics and molecular biology of gliomas over the past two decades and hundreds of clinical trials, no effective therapeutic approach has been identified for adult patients with newly diagnosed glioblastoma, and overall survival remains dismal. Great hopes are now placed on combination immunotherapy. In clinical trials, immunotherapeutics are generally tested after standard therapy (radiation, temozolomide, and steroid dexamethasone) or concurrently with temozolomide and/or steroids. Only a minor subset of patients with progressive/recurrent glioblastoma have benefited from immunotherapies. In this review, we comprehensively discuss standard therapy-related systemic immunosuppression and lymphopenia, their prognostic significance, and the implications for immunotherapy/oncolytic virotherapy. The effectiveness of immunotherapy and oncolytic virotherapy (viro-immunotherapy) critically depends on the activity of the host immune cells. The absolute counts, ratios, and functional states of different circulating and tumor-infiltrating immune cell subsets determine the net immune fitness of patients with cancer and may have various effects on tumor progression, therapeutic response, and survival outcomes. Although different immunosuppressive mechanisms operate in patients with glioblastoma/gliomas at presentation, the immunological competence of patients may be significantly compromised by standard therapy, exacerbating tumor-related systemic immunosuppression. Standard therapy affects diverse immune cell subsets, including dendritic, CD4+, CD8+, natural killer (NK), NKT, macrophage, neutrophil, and myeloid-derived suppressor cell (MDSC). Systemic immunosuppression and lymphopenia limit the immune system's ability to target glioblastoma. Changes in the standard therapy are required to increase the success of immunotherapies. Steroid use, high neutrophil-to-lymphocyte ratio (NLR), and low post-treatment total lymphocyte count (TLC) are significant prognostic factors for shorter survival in patients with glioblastoma in retrospective studies; however, these clinically relevant variables are rarely reported and correlated with response and survival in immunotherapy studies (e.g., immune checkpoint inhibitors, vaccines, and oncolytic viruses). Our analysis should help in the development of a more rational clinical trial design and decision-making regarding the treatment to potentially improve the efficacy of immunotherapy or oncolytic virotherapy.

Metformin use is associated with longer survival in glioblastoma patients with MGMT gene silencing

PURPOSE

New treatments are needed to improve the overall survival of patients with glioblastoma Metformin is known for anti-tumorigenic effects in cancers, including breast and pancreas cancers. In this study, we assessed the association between metformin use and overall survival in glioblastoma patients.

METHODS

We retrospectively studied 241 patients who underwent surgery at diagnosis of glioblastoma between 2014 and 2018. Metformin was used for pre-existing type 2 diabetes mellitus or in the prevention or management of glucocorticoid induced hyperglycemia. Kaplan-Meier curves and log-rank p test were used for univariate analysis. Cox-proportional hazards model was used to generate adjusted hazard ratios for multivariate analysis.

RESULTS

Metformin use was associated with longer survival in patients with tumors that had a methylated O6-methylguanine DNA methyltransferase gene (MGMT) promoter (484 days 95% CI: 56-911 vs. 394 days 95% CI: 249-538, Log-Rank test: 6.5, p = 0.01). Cox regression analysis shows that metformin associates with lower risk of death at 2 years in patients with glioblastoma containing a methylated MGMT promoter (aHR = 0.497, 95% CI 0.26-0.93, p = 0.028).

CONCLUSION

Our findings suggest a survival benefit with metformin use in patients with glioblastomas having methylation of the MGMT promoter.

Could Metformin and Resveratrol Support Glioblastoma Treatment? A Mechanistic View at the Cellular Level

Glioblastoma, a malignant brain tumor, is a common primary brain tumor in adults, with diabetes mellitus being a crucial risk factor. This review examines how the antidiabetic drug metformin and dietary supplement resveratrol can benefit the treatment of glioblastoma. Metformin and resveratrol have demonstrated action against relevant pathways in cancer cells. Metformin and resveratrol inhibit cell proliferation by downregulating the PI3K/Akt pathway, activating mTOR, and increasing AMPK phosphorylation, resulting in lower proliferation and higher apoptosis levels. Metformin and resveratrol both upregulate and inhibit different cascades in the MAPK pathway. In vivo, the drugs reduced tumor growth and volume. These actions show how metformin and resveratrol can combat cancer with both glucose-dependent and glucose-independent effects. The pre-clinical results, alongside the lack of clinical studies and the rise in novel delivery mechanisms, warrant further clinical investigations into the applications of metformin and resveratrol as both separate and as a combination complement to current glioblastoma therapies.

Characterization of perioperative glycemic status and dexamethasone use with associated postoperative complications in glioblastoma patients

PURPOSE

Postoperative morbidity in glioblastoma (GBM) patients can be due to the disease course but can also come from postoperative complications. Our objective was to study the association of dexamethasone use and perioperative hyperglycemia with postoperative complications in GBM patients.

METHODS

A single-center, retrospective cohort study was conducted in patients who underwent surgery for primary GBM from 2014-2018. Patients with perioperative fasting blood glucose (FBG) measurements and adequate follow-up to assess for complications were included.

RESULTS

A total of 199 patients were included. More than half (53%) had poor perioperative glycemic control (FBG ≥ 7 mM for ≥ 20% perioperative days). Higher dexamethasone dose (≥ 8 mg) was associated with higher FBG on postoperative days 2-4 and 5 (p = 0.02,0.05,0.004,0.02, respectively). Poor glycemic control was associated with increased odds of 30-day any complication and 30-day infection on univariate analysis (UVA), and 30-day any complication and increased length of stay (LOS) on multivariate analysis (MVA). Higher average perioperative daily dexamethasone dose was associated with increased odds of 30-day any complication and 30-day infection on MVA. Elevated hemoglobin A1c (HgbA1c, ≥ 6.5%) was associated with increased odds of 30-day any complication, 30-day infection, and LOS on UVA. In a multivariate linear regression model, only the diagnosis of diabetes mellitus predicted perioperative hyperglycemia.

CONCLUSIONS

Perioperative hyperglycemia, higher average dexamethasone use and elevated preoperative HgbA1c are associated with increased risk of postoperative complications in GBM patients. Avoiding hyperglycemia and limiting dexamethasone use in postoperative period may decrease the risk of complications. Select HgbA1c screening may allow the identification of a group of patients at higher risk of complications.

Significant Systemic Insulin Resistance is Associated With Unique Glioblastoma Multiforme Phenotype

Background

Some glioblastoma multiforme (GBM) are characterized by the presence of gemistocytes (GCs), a unique phenotype of reactive astrocytes. Certain GCs can be identified as neoplastic cells but these cells were also found to be associated with diabetes in non-neoplastic lesions of the central nervous system. Our aim was to find a correlation between insulin - resistance metabolic features and the presence of GCs in patients with newly diagnosed GBM.

Methods

Medical records from histologically confirmed GBM patients were retrospectively extracted for different systemic metabolic variables. A statistic-based comparison was made between GBM, diabetic patients with and without GC. Patients with poorly controlled diabetes (ie, hemoglobin A1C ⩾ 8.0) were also compared between the 2 groups.

Results

A total of 220 newly diagnosed GBM patients were included in our study. 58 (26.3%) patients had a history of diabetes mellitus type 2 (DM2) at the time of admission. The rate of poorly-controlled DM2 was nearly as twice in the GC-GBM group than in the non-GC GBM group (18.75% vs 9.5%; P = .130). In the DM2 cohort, the subgroup of GC-GBM was significantly associated with demographic and metabolic features related to insulin resistance such as male gender predominance (89% vs 50%, P = .073) and morbid obesity (weight ⩾85 kg: OR 6.16; P = .0019 and mean BMI: 34.1 ± 11.42 vs 28.7 ± 5.44; P = .034 for group with and without GCs, respectively). In the poorly-controlled DM2 group, none of the GC-GBM patients were using insulin prior to diagnosis, compared to 61.1% in the non-GC GBM patients (OR = 0.04, P = .045).

Conclusion

Systemic metabolic factors related to marked insulin resistance (DM2, morbid obesity, male gender) are associated with a unique histologic phenotype of GBM, characterized by the presence of GCs. This feature is prominent in poorly-controlled DM2 GBM patients who are not using synthetic insulin. This novel finding may add to the growing data on the relevance of glucose metabolism in astrocytes and in astrocytes associated with high-grade gliomas. In GBM patients, a correlation between patients' metabolic status, tumor's histologic phenotype, tumor's molecular changes, use of anti-diabetic drugs and the respective impact of these factor on survival warrants further investigation.

Hyperglycemia induces miR-26-5p down-regulation to overexpress PFKFB3 and accelerate epithelial–mesenchymal transition in gastric cancer

Gastric cancer (GC) is one of the most deadly malignancies with high morbidity worldwide. Cancer cells exhibited higher level of glucose catabolism than normal cells to meet the needs for rapid growth. Emerging evidences indicated that hyperglycemia has positive effects on the progression of tumor. As a vital regulator of glycolysis, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) was confirmed to have a higher expression level in tumor tissue and correlated with the prognosis of GC patients. However, the role of PFKFB3 in GC patients with hyperglycemia remains unclear. The data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were utilized to analyze the expression level of PFKFB3 and conducted survival analysis of GC patients. Western blot assay was used to detect gene expression at the protein level. Small interfering RNA (siRNA) transfection assay was conducted to down-regulate the expression of PFKFB3. Cell functional assays were carried out to reflect the ability of cell proliferation and migration. The results indicated that PFKFB3 was significantly upregulated and its overexpression was associated with poor prognosis of GC patients. Besides, hyperglycemia stimulated the higher expression of PFKFB3 along with the enhanced proliferation, migration and epithelial–mesenchymal transition (EMT) in GC cells. Knocking down of PFKFB3 effectively reversed the effects of high glucose concentration on GC malignant phenotype and the opposite results were gained when miR-26-5p was inhibited. Therefore, PFKFB3 down-regulated by miR-26-5p inhibited the malignant phenotype of GC with hyperglycemia.

Preoperative Predictors of Early Mortality Risk in Isocitrate Dehydrogenase-Wild-Type Glioblastoma Patients Treated with Standard Therapy

Purpose

Early identification of early mortality for glioblastoma (GBM) patients based on laboratory findings at the time of diagnosis could improve the overall survival. The study aimed to explore preoperative factors associated with higher risk of early death (within 1 year after surgery) for isocitrate dehydrogenase (IDH) -wild-type (wt) GBM patients.

Patients and Methods

We conducted a retrospective analysis of 194 IDH-wt GBM patients who underwent standard treatment. The probability of dying within 1 year after gross total resection (GTR) was defined as the end point “early mortality”. Retrospective collection of predictive factors including clinical characteristics and laboratory data at diagnosis.

Results

Median follow-up time after GTR was 16 months (3–41 months). Forty-two patients died within 1 year after surgery (1‐year mortality rate: 21.6%). All potential predictive factors were assessed on univariate analyses, which revealed the following factors as associated with higher risk of early death: older age (P = 0.013), occurrence of non-seizures symptoms (P = 0.042), special tumor positions (P = 0.046), higher neutrophil-to-lymphocyte ratio (NLR) (P = 0.015), higher red blood cell distribution width (RDW) (P = 0.019), higher lactate dehydrogenase (LDH) (P = 0.005), and higher fibrinogen (FIB) (P = 0.044). In a multivariate analysis, tumor location (P = 0.012), NLR (P = 0.032) and LDH (P = 0.002) were independent predictors of early mortality. The C-index of the nomogram was 0.795. The calibration curve showed good agreement between prediction by nomogram and actual observation.

Conclusion

Tumor location, preoperative elevated NLR and serum LDH level were independent predictors for 1‐year mortality after GTR. We indicate that increased preoperative NLR or LDH may guide patients to review head magnetic resonance imaging (MRI) more frequently and regularly to monitor tumor progression.

A Hematological-Related Prognostic Scoring System for Patients With Newly Diagnosed Glioblastoma

Background

Glioblastoma is the most common primary malignant brain tumor. Recent studies have shown that hematological biomarkers have become a powerful tool for predicting the prognosis of patients with cancer. However, most studies have only investigated the prognostic value of unilateral hematological markers. Therefore, we aimed to establish a comprehensive prognostic scoring system containing hematological markers to improve the prognostic prediction in patients with glioblastoma.

Patients and Methods

A total of 326 patients with glioblastoma were randomly divided into a training set and external validation set to develop and validate a hematological-related prognostic scoring system (HRPSS). The least absolute shrinkage and selection operator Cox proportional hazards regression analysis was used to determine the optimal covariates that constructed the scoring system. Furthermore, a quantitative survival-predicting nomogram was constructed based on the hematological risk score (HRS) derived from the HRPSS. The results of the nomogram were validated using bootstrap resampling and the external validation set. Finally, we further explored the relationship between the HRS and clinical prognostic factors.

Results

The optimal cutoff value for the HRS was 0.839. The patients were successfully classified into different prognostic groups based on their HRSs (P < 0.001). The areas under the curve (AUCs) of the HRS were 0.67, 0.73, and 0.78 at 0.5, 1, and 2 years, respectively. Additionally, the 0.5-, 1-y, and 2-y AUCs of the HRS were 0.51, 0.70, and 0.79, respectively, which validated the robust prognostic performance of the HRS in the external validation set. Based on both univariate and multivariate analyses, the HRS possessed a strong ability to predict overall survival in both the training set and validation set. The nomogram based on the HRS displayed good discrimination with a C-index of 0.81 and good calibration. In the validation cohort, a high C-index value of 0.82 could still be achieved. In all the data, the HRS showed specific correlations with age, first presenting symptoms, isocitrate dehydrogenase mutation status and tumor location, and successfully stratified them into different risk subgroups.

Conclusions

The HRPSS is a powerful tool for accurate prognostic prediction in patients with newly diagnosed glioblastoma.

Clinical Risk and Overall Survival in Patients with Diabetes Mellitus, Hyperglycemia and Glioblastoma Multiforme. A Review of the Current Literature

The relationship between type 2 diabetes mellitus (DM2) and hyperglycemia with cancer patients remains controversial also in the setting of patients with glioblastoma multiforme (GBM), the most common and aggressive form of astrocytoma with a short overall survival (OS) and poor prognosis. A systematic search of two databases was performed for studies published up to 19 August 2020, reporting the OS of patients with DM2 or high blood sugar level and GBM and the clinical risk of diabetic patients for development of GBM. According to PRISMA guidelines, we included a total of 20 papers reporting clinical data of patients with GBM and diabetes and/or hyperglycemia. The aim of this review was to investigate the effect of DM2, hyperglycemia and metformin on OS of patients with GBM. In addition, we evaluated the effect of these factors on the risk of development of GBM. This review supports accumulating evidence that hyperglycemia, rather than DM2, and elevated BMI are independent risk factors for poor outcome and shorter OS in patients with GBM. GBM patients with normal weight compared to obese, and diabetic patients on metformin compared to other therapies, seems to have a longer OS. Further studies are needed to understand better these associations.

Optimal Management of Corticosteroids in Patients with Intracranial Malignancies

OPINION STATEMENT

Corticosteroids have been essential in the management of brain tumor patients for decades, primarily for the treatment of peritumoral cerebral edema and its associated neurologic deficits. Dexamethasone is the drug of choice with standard practice being administration up to four times per day, however, because of its long biologic half-life and high potency, once or twice a day dosing is likely adequate in patients without elevated intracranial pressure. The length of corticosteroid treatment should be limited to the shortest period of time to minimize the risk of potential toxicities that can significantly affect quality of life, as well as to avoid a possible detrimental impact on survival in high-grade glioma patients and abrogation of the effect of immunotherapy. Agents such as bevacizumab should be considered in patients who are unable to wean completely off of steroids as well as those who have symptomatic edema and are on immunotherapy. Several other agents have been studied without much success. An increased understanding of the complex pathophysiology of peritumoral vasogenic edema is critically needed to discover new agents that are safer and more effective.

Influence of Hyperglycemia on Treatment Outcomes of Oral Cavity Squamous Cell Carcinoma

PURPOSE

The present study investigated the association between perioperative hyperglycemia and the treatment and survival outcomes of patients with oral cavity squamous cell carcinoma (OSCC).

PATIENTS AND METHODS

From 2004 to 2016, 385 patients with OSCC were enrolled and stratified into normoglycemic (<180 mg/dL) and hyperglycemic (≥180 mg/dL) groups. The clinicopathologic characteristics and treatment outcomes of OSCC were subsequently analyzed.

RESULTS

Of the 385 patients, 61 (15.8%) were in the hyperglycemic group. Hyperglycemia was significantly associated with pT stage, pN stage, overall pathologic stage, extranodal extension, albumin level, and tumor depth (P = .004, P = .042, P = .008, P = .001, P = .004, and P = .011, respectively). Patients with hyperglycemia also required a longer hospital stay (P = .003). The 5-year overall survival and disease-specific survival were poorer in the hyperglycemic group than in the normoglycemic group (P = .001 and P = .002, respectively). Multivariate analysis revealed that hyperglycemia is a significant adverse prognostic indicator for OSCC (hazard ratio, 1.709; 95% confidence interval, 1.003 to 2.912; P = .049).

CONCLUSIONS

Hyperglycemia is associated with more advanced disease and poorer survival rates in patients with OSCC. It correlates with adverse clinicopathologic characteristics and longer hospital stay. Screening for hyperglycemia and maintenance of normal glycemic status during the treatment course is imperative in the treatment of OSCC.

Postoperative hyperglycemia affects survival after gastrectomy for cancer: A single-center analysis using propensity score matching

BACKGROUND

No data are present currently on the potential correlation between postoperative hyperglycemia and long-term outcomes after gastric surgery for cancer. The aim of this study was to investigate the effects of postoperative hyperglycemia on survival after curative gastrectomy for cancer.

METHODS

All patients who underwent gastric surgery for cancer with curative intent were reviewed retrospectively. Diabetic patients and patients who needed pancreatic resection were excluded. In all patients, a prepared intravenous infusion of NaCl and carbohydrates (Isolyte Baxter 2,000 mL/day; glucose 50.0 g/L;Ringers lactate 1,000 mL/day) was used, and the patients were kept nil by mouth until the fourth postoperative day. The glucose levels were monitored during the first 72 hours. The study population was divided into normoglycemic and hyperglycemic patients according to the blood glucose level (<140 mg/dL and ≥140 mg/dL, respectively). The 2 groups were matched for age, sex, type of operative procedure, TNM status, and lymph node status.

RESULTS

After matching, 104 patients were included for the analysis. Perioperative morbidity accounted for 18.3% with a greater rate for hyperglycemic patients (12% vs 31%; P = .018). When compared with normoglycemic patients, hyperglycemic patients had worse overall survival (45% vs 57%; P = .05) and worse disease-free survival (46% vs 68%; P = .02). On the multivariate analysis, hyperglycemia was an independent risk factor for a worse overall and disease-free survival.

CONCLUSION

Postoperative hyperglycemia owing to surgical stress conditions can affect postoperative outcomes. Additionally, hyperglycemia may be a factor that promotes gastric cancer progression.

Neuroanesthesiology Update

We provide a synopsis of innovative research, recurring themes, and novel experimental findings pertinent to the care of neurosurgical patients and critically ill patients with neurological diseases. We cover the following broad topics: general neurosurgery, spine surgery, stroke, traumatic brain injury, monitoring, and anesthetic neurotoxicity.

The Association Between Common Clinical Characteristics and Postoperative Morbidity and Overall Survival in Patients with Glioblastoma

BACKGROUND

The impact of noncancerous factors on the morbidity and mortality of glioblastoma multiforme (GBM) has not been well studied. Using a large surgical cohort, we examined the association between multiple clinical characteristics and postoperative morbidities and survival in patients with GBM.

MATERIALS AND METHODS

The study included 404 consecutive GBM patients who underwent initial tumor resection at MD Anderson Cancer Center between January 1, 2010, and December 31, 2014. Data about clinical characteristics, treatments, and postoperative complications were collected. The associations between clinical parameters and postoperative complications and survival were analyzed.

RESULTS

Charlson Comorbidity Index was positively related to a higher incidence of postoperative total (odds ratio [OR] = 1.20; p = .002) and neurological (OR = 1.18; p = .011) complications. Preoperative systolic blood pressure (SBp) over 140 mmHg was associated with a higher incidence of postoperative intracranial hemorrhage (OR = 4.42; p = .039) and longer hospital stay (OR = 2.48; p = .015). Greater postoperative fluctuation of SBp (OR = 1.14; p = .025) and blood glucose (mmol/L; OR = 1.48; p = .023) were related to a higher incidence of neurological complications, whereas higher postoperative blood glucose (OR = 0.64; p < .001) was related to a lower incidence. Long-term lower SBp (<124 mmHg; hazard ratio [HR] = 1.47; p = .010) and higher blood glucose (HR = 1.12; p < .001) were associated with shorter survival. Long-term serum albumin level (g/dL; HR = 0.32; p < .001) was positively associated with survival.

CONCLUSION

Short-term SBp and blood glucose levels and fluctuations are associated with postoperative complications in GBM patients. Their long-term optimization may impact survival of these patients. Future clinical trials are needed to confirm the benefit of optimizing medical comorbidities on GBM patients' outcomes.

IMPLICATIONS FOR PRACTICE

Glioblastoma multiforme (GBM) is one of the most feared cancer diagnoses because of its limited survival and treatment. This study revealed significant associations of noncancerous factors on the morbidity and mortality of GBM. The complexity of medical comorbidities, as well as short-term postoperative levels and fluctuations of blood pressure and blood glucose, was associated with postoperative complications, but not overall survival. However, long-term levels of these common clinical parameters were significantly associated with survival. Optimization of medical conditions may be critical for reducing the morbidity and mortality of GBM patients. Future clinical trials are needed to validate the observed associations in an independent cohort.