Therapeutic options for recurrent malignant glioma

Prospective Randomized Phase 2 Trial of Hypofractionated Stereotactic Radiation Therapy of 25 Gy in 5 Fractions Compared With 35 Gy in 5 Fractions in the Reirradiation of Recurrent Glioblastoma

PURPOSE

The aim of this work was to investigate whether reirradiation of recurrent glioblastoma with hypofractionated stereotactic radiation therapy (HSRT) consisting of 35 Gy in 5 fractions (35 Gy/5 fx) compared with 25 Gy in 5 fractions (25 Gy/5 fx) improves outcomes while maintaining acceptable toxicity.

METHODS AND MATERIALS

We conducted a prospective randomized phase 2 trial involving patients with recurrent glioblastoma (per the 2007 and 2016 World Health Organization classification). A minimum interval from first radiation therapy of 5 months and gross tumor volume of 150 cc were required. Patients were randomized 1:1 to receive HSRT alone in 25 Gy/5 fx or 35 Gy/5 fx. The primary endpoint was progression-free survival (PFS). We used a randomized phase 2 screening design with a 2-sided α of 0.15 for the primary endpoint.

RESULTS

From 2011 to 2019, 40 patients were randomized and received HSRT, with 20 patients in each group. The median age was 50 years (range, 27-71); a new resection before HSRT was performed in 75% of patients. The median PFS was 4.9 months in the 25 Gy/5 fx group and 5.2 months in the 35 Gy/5 fx group (P = .23). Six-month PFS was similar at 40% (85% CI, 24%-55%) for both groups. The median overall survival (OS) was 9.2 months in the 25 Gy/5 fx group and 10 months in the 35 Gy/5 fx group (P = .201). Grade ≥3 necrosis was numerically higher in the 35 Gy/5 fx group (3 [16%] vs 1 [5%]), but the difference was not statistically significant (P = .267). In an exploratory analysis, median OS of patients who developed treatment-related necrosis was 14.1 months, and that of patients who did not was 8.7 months (P = .003).

CONCLUSIONS

HSRT alone with 35 Gy/5 fx was not superior to 25 Gy/5 fx in terms of PFS or OS. Due to a potential increase in the rate of clinically meaningful treatment-related necrosis, we suggest 25 Gy/5 fx as the standard dose in HSRT alone. During follow-up, attention should be given to differentiating tumor progression from potentially manageable complications.

TCAF2 drives glioma cellular migratory/invasion properties through STAT3 signaling

Glioma is an intracranial tumor characterized by high mortality and recurrence rates. In the present study, the association of TRPM8 channel-associated factor 2 (TCAF2) in glioma was investigated using bioinformatics, showing significant relationships with age, WHO grade, IDH, and 1p/19q status, as well as being an independent predictor of prognosis. Immunohistochemistry of a glioma sample microarray showed markedly increased TCAF2 expression in glioblastoma relative to lower-grade glioma, with elevated expression predominating in the tumor center. Raised TCAF2 levels promote glioma cell migratory/invasion properties through the epithelial-to-mesenchymal transition-like (EMT-like) process, shown by Transwell and scratch assays and western blotting. It was further found that the effects of TCAF2 were mediated by the activation of STAT3. These results suggest that TCAF2 promotes glioma cell migration and invasion, rendering it a potential drug target in glioma therapy.

High-dose salvage re-irradiation in recurrent/progressive adult diffuse gliomas: development of a novel prognostic scoring system

PURPOSE

Over the past two decades, high-dose salvage re-irradiation (re-RT) has been used increasingly in the multimodality management of adults with recurrent/progressive diffuse glioma. Several factors that determine outcomes following re-RT have been incorporated into prognostic models to guide patient selection. We aimed to develop a novel four-tiered prognostic model incorporating relevant molecular markers from our single-institutional cohort of patients treated with high-dose salvage re-RT for recurrent/progressive diffuse glioma.

MATERIAL AND METHODS

Various patient, disease, and treatment-related factors impacting upon survival following salvage re-RT were identified through univariate analysis. Each of these prognostic factors was further subdivided and assigned scores of 0 (low-risk), 1 (intermediate-risk), or 2 (high-risk). Scores from individual prognostic factors were added to derive the cumulative score (ranging from 0 to 16), with increasing scores indicating worsening prognosis.

RESULTS

A total of 111 adults with recurrent/progressive diffuse glioma treated with salvage high-dose re-RT were included. We could assign patients into four prognostic subgroups (A=15 patients, score 0-3); (B=50 patients, score 4-7); (C=33 patients, score 8-10); and (D=13 patients, score 11-16) with completely non-overlapping survival curves suggesting the good discriminatory ability. Post-re-RT survival was significantly higher in Group A compared to groups B, C, and D, respectively (stratified log-rank p-value <0.0001).

CONCLUSION

There exists a lack of universally acceptable 'standard-of-care' salvage therapy for recurrent/progressive diffuse glioma. A novel four-tiered prognostic scoring system incorporating traditional factors as well as relevant molecular markers is proposed for selecting patients appropriately for high-dose salvage re-RT that warrants validation in a non-overlapping cohort.

Gliomas: Genetic alterations, mechanisms of metastasis, recurrence, drug resistance, and recent trends in molecular therapeutic options

Glioma is the most common intracranial tumor with poor treatment outcomes and has high morbidity and mortality. Various studies on genomic analyses of glioma found a variety of deregulated genes with somatic mutations including TERT, TP53, IDH1, ATRX, TTN, etc. The genetic alterations in the key genes have been demonstrated to play a crucial role in gliomagenesis by modulating important signaling pathways that alter the fundamental intracellular functions such as DNA damage and repair, cell proliferation, metabolism, growth, wound healing, motility, etc. The SPRK1, MMP2, MMP9, AKT, mTOR, etc., genes, and noncoding RNAs (miRNAs, lncRNAs, circRNAs, etc) were shown mostly to be implicated in the metastases of glioma. Despite advances in the current treatment strategies, a low-grade glioma is a uniformly fatal disease with overall median survival of ∼5-7 years while the patients bearing high-grade tumors display poorer median survival of ∼9-10 months mainly due to aggressive metastasis and therapeutic resistance. This review discusses the spectrum of deregulated genes, molecular and cellular mechanisms of metastasis, recurrence, and its management, the plausible causes for the development of therapy resistance, current treatment options, and the recent trends in malignant gliomas. Understanding the pathogenic mechanisms and advances in molecular genetics would aid in the novel diagnosis, prognosis, and translation of pathogenesis-based treatment opportunities which could pave the way for precision medicine in glioma.

Anticancer effects of veratramine via the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin and its downstream signaling pathways in human glioblastoma cell lines

AIMS

Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma.

MAIN METHODS

Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively.

KEY FINDINGS

Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G₀/G₁ phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines.

SIGNIFICANCE

Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway.

The effectiveness of gamma knife radiosurgery for the management of residual high-grade gliomas: A single institutional study

High-grade gliomas (HGGs) are presently managed via surgical resection, external beam radiation therapy (EBRT), and chemotherapy. Although Gamma Knife radiosurgery (GKRS) is currently used to manage HGGs, it has not been considered standard care. This paper aims to compare the contribution of GKRS to clinical outcomes in patients in which gross total resection (GTR) cannot be achieved. We retrospectively reviewed the data of 99 patients with HGG (World Health Organization (WHO) grade III and IV) from two groups: group 1 consisted of 68 patients for which only EBRT was administered, and group 2 consisted of 31 patients for which EBRT and GKRS were administered. Patient demographic data, the extent of resection, IDH mutation, radiation dosage, progression-free survival (PFS), overall survival (OS), and follow-up time were recorded and compared across groups. The grade III/IV tumor ratio was 10/58 and 10/21 in groups 1 and 2, respectively. In group 2, PFS and OS were higher than in group 1 (P = 0.030 and 0.021). The mean follow-up time was 15.02 ± 11.8 (3-52) and 18.9 ± 98.6 (7-43) months in groups 1 and 2, respectively. In addition to the standard management of HGGs in patients without GTR, boost GKRS during the early postoperative period is beneficial for increasing PFS and OS.

Clinical Studies on Ultrafractionated Chemoradiation: A Systematic Review

Aim

The efficacy of low-dose fractionated radiotherapy (LDFRT) and chemotherapy (CHT) combination has large preclinical but little clinical evidence. Therefore, the aim of this review was to collect and analyze the clinical results of LDRT plus concurrent CHT in patients with advanced cancers.

Methods

A systematic literature search was conducted on PubMed using the PRISMA methodology. Only studies based on the combination of LDFRT (< 1 Gy/fraction) and CHT were included. Endpoints of the analysis were tumor response, toxicity, and overall survival, with particular focus on any differences between LDFRT-CHT and CHT alone.

Results

Twelve studies (307 patients) fulfilled the selection criteria and were included in this review. Two studies were retrospective, one was a prospective pilot trial, six were phase II studies, two were phase I trials, and one was a phase I/II open label study. No randomized controlled trials were found. Seven out of eight studies comparing clinical response showed higher rates after LDFRT-CHT compared to CHT alone. Three out of four studies comparing survival reported improved results after combined treatment. Three studies compared toxicity of CHT and LDFRT plus CHT, and all of them reported similar adverse events rates. In most cases, toxicity was manageable with only three likely LDFRT-unrelated fatal events (1%), all recorded in the same series on LDFRT plus temozolomide in glioblastoma multiforme patients.

Conclusion

None of the analyzed studies provided level I evidence on the clinical impact of LDFRT plus CHT. However, it should be noted that, apart from two small series of breast cancers, all studies reported improved therapeutic outcomes and similar tolerability compared to CHT alone.

Systematic Review Registration

www.crd.york.ac.uk/prospero/, identifier CRD42020206639.

Re-irradiation for high-grade gliomas: Has anything changed?

Optimal management after recurrence or progression of high-grade gliomas is still undefined and remains a challenge for neuro-oncology multidisciplinary teams. Improved radiation therapy techniques, new imaging methods, published experience, and a better radiobiological knowledge of brain tissue have positioned re-irradiation (re-RT) as an option for many of these patients. Decisions must be individualized, taking into account the pattern of relapse, previous treatment, and functional status, as well as the patient’s preferences and expected quality of life. Many questions remain unanswered with respect to re-RT: Who is the most appropriate candidate, which dose and fractionation are most effective, how to define the target volume, which imaging technique is best for planning, and what is the optimal timing? This review will focus on describing the most relevant studies that include re-RT as salvage therapy, with the aim of simplifying decision-making and designing the best available therapeutic strategy.

Treatment options for progression or recurrence of glioblastoma: a network meta-analysis

BACKGROUND

Glioblastoma (GBM) is a highly malignant brain tumour that almost inevitably progresses or recurs after first line standard of care. There is no consensus regarding the best treatment/s to offer people upon disease progression or recurrence. For the purposes of this review, progression and recurrence are considered as one entity.

OBJECTIVES

To evaluate the effectiveness of further treatment/s for first and subsequent progression or recurrence of glioblastoma (GBM) among people who have received the standard of care (Stupp protocol) for primary treatment of the disease; and to prepare a brief economic commentary on the available evidence.

SEARCH METHODS

We searched MEDLINE and Embase electronic databases from 2005 to December 2019 and the Cochrane Central Register of Controlled Trials (CENTRAL, in the Cochrane Library; Issue 12, 2019). Economic searches included the National Health Service Economic Evaluation Database (NHS EED) up to 2015 (database closure) and MEDLINE and Embase from 2015 to December 2019.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and comparative non-randomised studies (NRSs) evaluating effectiveness of treatments for progressive/recurrent GBM. Eligible studies included people with progressive or recurrent GBM who had received first line radiotherapy with concomitant and adjuvant temozolomide (TMZ).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data to a pre-designed data extraction form. We conducted network meta-analyses (NMA) and ranked treatments according to effectiveness for each outcome using the random-effects model and Stata software (version 15). We rated the certainty of evidence using the GRADE approach.

MAIN RESULTS

We included 42 studies: these comprised 34 randomised controlled trials (RCTs) and 8 non-randomised studies (NRSs) involving 5236 participants. We judged most RCTs to be at a low risk of bias and NRSs at high risk of bias. Interventions included chemotherapy, re-operation, re-irradiation and novel therapies either used alone or in combination. For first recurrence, we included 11 interventions in the network meta-analysis (NMA) for overall survival (OS), and eight in the NMA for progression-free survival (PFS). Lomustine (LOM; also known as CCNU) was the most common comparator and was used as the reference treatment. No studies in the NMA evaluated surgery, re-irradiation, PCV (procarbazine, lomustine, vincristine), TMZ re-challenge or best supportive care. We could not perform NMA for second or later recurrence due to insufficient data. Quality-of-life data were sparse. First recurrence (NMA findings) Median OS across included studies in the NMA ranged from 5.5 to 12.6 months and median progression-free survival (PFS) ranged from 1.5 months to 4.2 months. We found no high-certainty evidence that any treatments tested were better than lomustine. These treatments included the following. Bevacizumab plus lomustine: Evidence suggested probably little or no difference in OS between bevacizumab (BEV) combined with lomustine (LOM) and LOM monotherapy (hazard ratio (HR) 0.91, 0.75 to 1.10; moderate-certainty evidence), although BEV + LOM may improve PFS (HR 0.57, 95% confidence interval (CI) 0.44 to 0.74; low-certainty evidence). Bevacizumab monotherapy: Low-certainty evidence suggested there may be little or no difference in OS (HR 1.22, 95% CI 0.84 to 1.76) and PFS (HR 0.90, 95% CI 0.58 to 1.38; low-certainty evidence) between BEV and LOM monotherapies; more evidence on BEV is needed. Regorafenib (REG): REG may improve OS compared with LOM (HR 0.50, 95% CI 0.33 to 0.76; low-certainty evidence). Evidence on PFS was very low certainty and more evidence on REG is needed. Temozolomide (TMZ) plus Depatux-M (ABT414): For OS, low-certainty evidence suggested that TMZ plus ABT414 may be more effective than LOM (HR 0.66, 95% CI 0.47 to 0.92) and may be more effective than BEV (HR 0.54, 95% CI 0.33 to 0.89; low-certainty evidence). This may be due to the TMZ component only and more evidence is needed. Fotemustine (FOM): FOM and LOM may have similar effects on OS (HR 0.89, 95% CI 0.51 to 1.57, low-certainty evidence). Bevacizumab and irinotecan (IRI): Evidence on BEV + irinotecan (IRI) versus LOM for both OS and PFS is very uncertain and there is probably little or no difference between BEV + IRI versus BEV monotherapy (OS: HR 0.95, 95% CI 0.70 to 1.30; moderate-certainty evidence). When treatments were ranked for OS, FOM ranked first, BEV + LOM second, LOM third, BEV + IRI fourth, and BEV fifth. Ranking does not take into account the certainty of the evidence, which also suggests there may be little or no difference between FOM and LOM. Other treatments Three studies evaluated re-operation versus no re-operation, with or without re-irradiation and chemotherapy, and these suggested possible survival advantages with re-operation within the context of being able to select suitable candidates for re-operation. A cannabinoid treatment in the early stages of evaluation, in combination with TMZ, merits further evaluation. Second or later recurrence Limited evidence from three heterogeneous studies suggested that radiotherapy with or without BEV may have a beneficial effect on survival but more evidence is needed. Evidence was insufficient to draw conclusions about the best radiotherapy dosage. Other evidence suggested that there may be little difference in survival with tumour-treating fields compared with physician's best choice of treatment. We found no reliable evidence on best supportive care. Severe adverse events (SAEs) The BEV+LOM combination was associated with significantly greater risk of SAEs than LOM monotherapy (RR 2.51, 95% CI 1.72 to 3.66, high-certainty evidence), and ranked joint worst with cediranib + LOM (RR 2.51, 95% CI 1.29 to 4.90; high-certainty evidence). LOM ranked best and REG ranked second best. Adding novel treatments to BEV was generally associated with a higher risk of severe adverse events compared with BEV alone.

AUTHORS' CONCLUSIONS

For treatment of first recurrence of GBM, among people previously treated with surgery and standard chemoradiotherapy, the combination treatments evaluated did not improve overall survival compared with LOM monotherapy and were often associated with a higher risk of severe adverse events. Limited evidence suggested that re-operation with or without re-irradiation and chemotherapy may be suitable for selected candidates. Evidence on second recurrence is sparse. Re-irradiation with or without bevacizumab may be of value in selected individuals, but more evidence is needed.

Role of Hyperbaric Oxygenation Plus Hypofractionated Stereotactic Radiotherapy in Recurrent High-Grade Glioma

BACKGROUND

The presence of hypoxic cells in high-grade glioma (HGG) is one of major reasons for failure of local tumour control with radiotherapy (RT). The use of hyperbaric oxygen therapy (HBO) could help to overcome the problem of oxygen deficiency in poorly oxygenated regions of the tumour. We propose an innovative approach to improve the efficacy of hypofractionated stereotactic radiotherapy (HSRT) after HBO (HBO-RT) for the treatment of recurrent HGG (rHGG) and herein report the results of an ad interim analysis.

METHODS

We enrolled a preliminary cohort of 9 adult patients (aged >18 years) with a diagnosis of rHGG. HSRT was administered in daily 5-Gy fractions for 3-5 consecutive days a week. Each fraction was delivered up to maximum of 60 minutes after HBO.

RESULTS

Median follow-up from re-irradiation was 11.6 months (range: 3.2-11.6 months). The disease control rate (DCR) 3 months after HBO-RT was 55.5% (5 patients). Median progression-free survival (mPFS) for all patients was 5.2 months (95%CI: 1.34-NE), while 3-month and 6-month PFS was 55.5% (95%CI: 20.4-80.4) and 27.7% (95%CI: 4.4-59.1), respectively. Median overall survival (mOS) of HBO-RT was 10.7 months (95% CI: 7.7-NE). No acute or late neurologic toxicity >grade (G)2 was observed in 88.88% of patients. One patient developed G3 radionecrosis.

CONCLUSIONS

HSRT delivered after HBO appears to be effective for the treatment of rHGG, it could represent an alternative, with low toxicity, to systemic therapies for patients who cannot or refuse to undergo such treatments.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT03411408.

M2 macrophage-derived exosomal microRNAs inhibit cell migration and invasion in gliomas through PI3K/AKT/mTOR signaling pathway

Background

Glioma, the most common primary brain tumor, account Preparing figures for 30 to 40% of all intracranial tumors. Herein, we aimed to study the effects of M2 macrophage-derived exosomal microRNAs (miRNAs) on glioma cells.

Methods

First, we identified seven differentially expressed miRNAs in infiltrating macrophages and detected the expression of these seven miRNAs in M2 macrophages. We then selected hsa-miR-15a-5p (miR-15a) and hsa-miR-92a-3p (miR-92a) for follow-up studies, and confirmed that miR-15a and miR-92a were under-expressed in M2 macrophage exosomes. Subsequently, we demonstrated that M2 macrophage-derived exosomes promoted migration and invasion of glioma cells, while exosomal miR-15a and miR-92a had the opposite effects on glioma cells. Next, we performed the target gene prediction in four databases and conducted target gene validation by qRT-PCR, western blot and dual luciferase reporter gene assays.

Results

The results revealed that miR-15a and miR-92a were bound to CCND1 and RAP1B, respectively. Western blot assays demonstrated that interference with the expression of CCND1 or RAP1B reduced the phosphorylation level of AKT and mTOR, indicating that both CCND1 and RAP1B can activate the PI3K/AKT/mTOR signaling pathway.

Conclusion

Collectively, these findings indicate that M2 macrophage-derived exosomal miR-15a and miR-92a inhibit cell migration and invasion of glioma cells through PI3K/AKT/mTOR signaling pathway.

Supplementary information

The online version contains supplementary material available at 10.1186/s12967-021-02766-w.

Radiation necrosis after a combination of external beam radiotherapy and iodine-125 brachytherapy in gliomas

PURPOSE

Frequency and risk profile of radiation necrosis (RN) in patients with glioma undergoing either upfront stereotactic brachytherapy (SBT) and additional salvage external beam radiotherapy (EBRT) after tumor recurrence or vice versa remains unknown.

METHODS

Patients with glioma treated with low-activity temporary iodine-125 SBT at the University of Munich between 1999 and 2016 who had either additional upfront or salvage EBRT were included. Biologically effective doses (BED) were calculated. RN was diagnosed using stereotactic biopsy and/or metabolic imaging. The rate of RN was estimated with the Kaplan Meier method. Risk factors were obtained from logistic regression models.

RESULTS

Eighty-six patients (49 male, 37 female, median age 47 years) were included. 38 patients suffered from low-grade and 48 from high-grade glioma. Median follow-up was 15 months after second treatment. Fifty-eight patients received upfront EBRT (median total dose: 60 Gy), and 28 upfront SBT (median reference dose: 54 Gy, median dose rate: 10.0 cGy/h). Median time interval between treatments was 19 months. RN was diagnosed in 8/75 patients. The 1- and 2-year risk of RN was 5.1% and 11.7%, respectively. Tumor volume and irradiation time of SBT, number of implanted seeds, and salvage EBRT were risk factors for RN. Neither of the BED values nor the time interval between both treatments gained prognostic influence.

CONCLUSION

The combination of upfront EBRT and salvage SBT or vice versa is feasible for glioma patients. The risk of RN is mainly determined by the treatment volume but not by the interval between therapies.

High-dose salvage re-irradiation for recurrent/progressive adult diffuse glioma: healing or hurting?

PURPOSE

To report survival outcomes and identify prognostic factors of salvage re-irradiation (re-RT) in recurrent/progressive glioma.

METHODS

Medical records of patients treated with high-dose re-RT as part of multi-modality salvage therapy for recurrence/progression of adult diffuse glioma from 2010 to 2019 were analyzed retrospectively.

RESULTS

A total of 111 patients developing recurrent/progressive high-grade glioma after adequate upfront treatment at initial diagnosis were included. The first course of radiotherapy (RT) had been delivered to a median dose of 59.4 Gy with an inter-quartile range (IQR) of 54-60 Gy. Median time to recurrence/progression was 4.3 years (IQR = 2.3-7.4 years) while the median time to re-RT was 4.8 years (IQR = 3.6-7.9 years). Re-RT was delivered with intensity-modulated radiation therapy (IMRT) using 1.8 Gy/fraction to a median dose of 54 Gy (IQR = 50.4-55.8 Gy) for a cumulative median equivalent dose in 2-Gy fractions (EQD2) of 104.3 Gy (IQR = 102.6-109.4 Gy). At a median follow-up of 14 months after re-RT, the 1-year Kaplan-Meier estimates of post-re-RT progression-free survival (PFS) and overall survival (OS) were 42.8 and 61.8%, respectively. Univariate analysis identified histological grade at recurrence/progression; histological subtype; disease-free interval (DFI) and time interval between both courses of RT; performance status at re-RT; dose at re-RT and cumulative EQD2; isocitrate dehydrogenase (IDH) mutation; and O⁶-methyl-guanine DNA methyl transferase (MGMT) gene promoter methylation as significant prognostic factors. Preserved performance status, longer DFI, prolonged time interval between both courses of RT, and presence of IDH mutation were associated with significantly improved PFS on multi-variate analysis. However, only performance status retained independent prognostic significance for OS on multi-variate analysis. Post-treatment changes were seen in 33 (30%) patients on follow-up imaging, with higher cumulative dose (EQD2 ≥ 104.3 Gy) being associated with increased risk of post-re-RT pseudo-progression.

CONCLUSION

This clinical audit reports encouraging survival outcomes and identifies key prognostic factors associated with high-dose salvage re-RT in recurrent/progressive glioma.

Re-irradiation of recurrent glioblastoma using helical TomoTherapy with simultaneous integrated boost: preliminary considerations of treatment efficacy

Although there is still no standard treatment for recurrent glioblastoma multiforme (rGBM), re-irradiation could be a therapeutic option. We retrospectively evaluated the efficacy and safety of re-irradiation using helical TomoTherapy (HT) with a simultaneous integrated boost (SIB) technique in patients with rGBM. 24 patients with rGBM underwent HT-SIB. A total dose of 20 Gy was prescribed to the Flair (fluid-attenuated inversion recovery) planning tumor volume (PTV) and 25 Gy to the PTV-boost (T1 MRI contrast enhanced area) in 5 daily fractions to the isodose of 67% (maximum dose within the PTV-boost was 37.5 Gy). Toxicity was evaluated by converting the 3D-dose distribution to the equivalent dose in 2 Gy fractions on a voxel-by-voxel basis. Median follow-up after re-irradiation was 27.8 months (range 1.6-88.5 months). Median progression-free survival (PFS) was 4 months (95% CI 2.0-7.9 months), while 6-month PFS was 41.7% (95% CI 22.2-60.1 months). Median overall survival following re-irradiation was 10.7 months (95% CI 7.4-16.1 months). There were no cases of re-operation due to early or late toxicity. Our preliminary results suggest that helical TomoTherapy with the proposed SIB technique is a safe and feasible treatment option for patients with rGBM, including those large disease volumes, reducing toxicity.

Anticancer Effect in Human Glioblastoma and Antioxidant Activity of Petroselinum crispum L. Methanol Extract

Parsley (Petroselinum crispum L.) has been used as food, spices and in folkloric medicine. Several scientific researches have been focalized on anti-inflammatory, anti-proliferative, antioxidant and other pharmacological activities of parsley. The aim of the present study was to evaluate the phytochemical composition, antioxidant and anticancer activity of P. crispum L aqueous and methanol extracts against Human glioblastoma cells U87MG. Adhesion assay was realized on different protein matrices (fibrinogen, fibronectin and poly-L-lysine) and the anti-proliferative effect was performed. Compared to aqueous extract, the methanol extract presented an important level of phenol contents. Five phenolic compounds were found using HPLC-DAD with quinic acid as the most abounded followed by gallic acid, acacetin, protocatechuic acid and Cirsilineol with 120753.07 ± 27450; 190 ± 25; 53.83 ± 10; 13.7 ± 2.5 and 2 ± 0.3 µg/mL respectively.The DPPH, ABTS+, OH radical, Iron (II) chelation and FRAP assays exhibited that methanol extract show a modulate antioxidant activity. The methanol extract shows the highest ability to inhibit cell adhesion to different protein matrices. In addition, it was found as a potential anti-proliferative. These results suggest for the first time that P. crispum methanol extract presents anti-adhesion and anti-proliferative proprieties.

Prospective Longitudinal Assessment of Quality of Life and Activities of Daily Living as Patient-Reported Outcome Measures in Recurrent/Progressive Glioma Treated with High-dose Salvage Re-irradiation

AIMS

To evaluate quality of life (QOL) and activities of daily living (ADL) longitudinally in patients treated with salvage re-irradiation for recurrent/progressive glioma. Secondary end points included post-re-irradiation survival.

MATERIALS AND METHODS

Patients with diffuse glioma, aged 18-70 years with preserved performance status and unequivocal evidence of recurrence/progression with a minimum 2-year time interval from index radiation therapy were eligible. QOL was assessed by the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core-30 (QLQ-C30) and brain cancer module (BN20). ADL was assessed using a modified Barthel's index. Assessments were carried out longitudinally, first before re-irradiation, at completion of re-irradiation and subsequently periodically on follow-up. Summary scores were calculated from raw scores as per the EORTC scoring manual; higher functional scores and lower symptom scores indicating better QOL. Summary mean scores for the modified Barthel's index were also calculated, with lower scores indicating higher disability. Differences between the summary scores at different time points were tested using the Friedman test.

RESULTS

In total, 225 assessments were carried out in 60 patients accrued on the study. A significant improvement in scores was noted for physical function (P < 0.001), emotional function (P = 0.002), cognitive function (P = 0.009) and social functioning (P = 0.047) over time. Role function scores (P = 0.182) and global health status scores (P = 0.074) remained stable. Among symptom scores, fatigue showed a statistically significant improvement over time (P = 0.01), whereas other symptom scores remained largely stable. There was a significant increase in the modified Barthel's index score over time (P = 0.001), suggesting greater functional independence. At a median follow-up of 12.9 months, the 1-year Kaplan-Meier estimates with 95% confidence intervals of post-re-irradiation progression-free survival and overall survival were 45.1% (31.5-58.7%) and 62.2% (49.2-75.2%), respectively.

CONCLUSIONS

High-dose salvage re-irradiation in carefully selected patients with recurrent/progressive glioma is associated with stable QOL (preserved functional domains and reduced symptom burden) and improvement in ADL (greater functional independence) over time with encouraging survival outcomes.

Low Fraction Size Re-irradiation for Large Volume Recurrence of Glial Tumours

The aim of the present study was to evaluate the efficacy of re-irradiation (re-RT) in patients with advanced local relapses of glial tumours and to define the factors influencing the result of the hyper-fractionated external beam therapy on progression after primary management. We have analysed the data of 55 patients with brain tumours (GBM: 28) on progression, who were re-irradiated between January 2007 and December 2018. The mean volume of the recurrent tumour was 118 cm³, and the mean planning target volume (PTV) was 316 cm³, to which 32 Gy was delivered in 20 fractions at least 7.7 months after the first radiotherapy, using 3D conformal radiotherapy (CRT) or intensity modulated radiotherapy (IMRT). The median overall survival (mOS) from the re-RT was 8.4 months, and the 6-month and the 12-month OS rate was 64% and 31%, respectively. The most important factors by univariate analysis, which significantly improved the outcome of re-RT were the longer time interval between the diagnosis and second radiotherapy (p = 0.029), the lower histology grade (p = 0.034), volume of the recurrent tumour (p = 0.006) and Karnofsky performance status (KPS) (p = 0.009) at the re-irradiation. Our low fraction size re-irradiation ≥ 8 months after the first radiotherapy proved to be safe and beneficial for patients with large volume recurrent glial tumours.

Upregulation of miR-1825 inhibits the progression of glioblastoma by suppressing CDK14 though Wnt/β-catenin signaling pathway

BACKGROUND

Mounting evidences displayed that miRNAs play crucial roles in tumor initiation and development. However, the regulation and relevant mechanism of miR-1825 in glioblastoma (GBM) remain unclear.

METHODS

qRT-PCR was used to detect miR-1825 and CDK14 mRNA expression. Western blot was applied for testing protein levels (VEGF, E-cadherin, N-cadherin, vimentin, β-catenin, c-myc, p-c-Jun). MTT and transwell assays were used for detecting GBM cell progression, including cell viability, migration, and invasion.

RESULTS

The results showed that miR-1825 was decreased in GBM tissue specimens by qRT-PCR and it was confirmed as a prognostic marker of GBM by Kaplan-Meier survival analysis. Moreover, we also found that miR-1825 upregulation suppressed GBM cell viability, tumor growth, invasion, and migration. Furthermore, CDK14 was first identified as the direct target of miR-1825 by Luciferase reporter assay. CDK14 acted as an oncogene in GBM development by immunohistochemistry. In addition, Western blot analysis demonstrated that miR-1825 regulated Wnt/β-catenin signaling pathway in GBM development.

CONCLUSION

In conclusion, miR-1825 upregulation suppressed GBM progression by targeting CDK14 through Wnt/β-catenin pathway.

A novel three-dimensional template combined with MR-guided 125I brachytherapy for recurrent glioblastoma

Background

At present, the treatment of recurrent glioblastoma is extremely challenging. In this study, we used a novel three-dimensional non-coplanar template (3DNPT) combined with open MR to guide ¹²⁵I seed implantation for recurrent glioblastoma. The aim of this study was to evaluate the feasibility, accuracy, and effectiveness of this technique.

Methods

Twenty-four patients of recurrent glioblastoma underwent 3DNPT with open MR-guided ¹²⁵I brachytherapy from August 2017 to January 2019. Preoperative treatment plan and 3DNPT were made according to enhanced isovoxel T1-weighted MR images. ¹²⁵I seeds were implanted using 3DNPT and 1.0-T open MR imaging guidance. Dosimetry verification was performed after brachytherapy based on postoperative CT/MR fusion images. Preoperative and postoperative dosimetry parameters of D90, V100, V200, conformity index (CI), external index (EI) were compared. The objective response rate (ORR) at 6 months and 1-year survival rate were calculated. Median overall survival (OS) measured from the date of brachytherapy was estimated by Kaplan-Meier method.

Results

There were no significant differences between preoperative and postoperative dosimetry parameters of D90, V100, V200, CI, EI (P > 0.05). The ORR at 6 months was 75.0%. The 1-year survival rate was 58.3%. Median OS was 12.9 months. One case of small amount of epidural hemorrhage occurred during the procedure. There were 3 cases of symptomatic brain edema after brachytherapy treatment, including grade three toxicity in 1 case and grade two toxicity in 2 cases. The three patients were treated with corticosteroid for 2 to 4 weeks. The clinical symptoms related to brain edema were significantly alleviated thereafter.

Conclusions

3DNPT combined with open MR-guided ¹²⁵I brachytherapy for circumscribed recurrent glioblastoma is feasible, effective, and with low risk of complications. Postoperative dosimetry matched the preoperative treatment plan. The described method can be used as a novel implantation technique for ¹²⁵I brachytherapy in the treatment of recurrent gliomas.

Trial registration

The study was approved by the Institutional Review Board of Shandong Provincial Hospital Affiliated to Shandong University (NSFC:NO.2017–058), registered 1st July 2017.

Report of first recurrent glioma patients examined with PET-MRI prior to re-irradiation

Background and purpose

The advantage of combined PET-MRI over sequential PET and MRI is the high spatial conformity and the absence of time delay between the examinations. The benefit of this technique for planning of re-irradiation (re-RT) treatment is unkown yet. Imaging data from a phase 1 trial of re-RT for recurrent glioma was analysed to assess whether planning target volumes and treatment margins in glioma re-RT can be adjusted by PET-MRI with rater independent PET based biological tumour volumes (BTVs).

Patients and methods

Combined PET-MRI with the tracer O-(2-¹⁸F-fluoroethyl)-l-tyrosine (¹⁸F-FET) prior to re-RT was performed in recurrent glioma patients in a phase I trial. GTVs including all regions suspicious of tumour on contrast enhanced MRI were delineated by three experienced radiation oncologists and included into MRI based consensus GTVs (_MRGTVs). BTVs were semi-automatically delineated with a fixed threshold of 1.6 x background activity. Corresponding BTVs and _MRGTVs were fused into union volume _PET-MRGTVs. The Sørensen–Dice coefficient and the conformity index were used to assess the geometric overlap of the BTVs with the _MRGTVs. A recurrence pattern analysis was performed based on the original planning target volumes (PTVs = GTV + 10 mm margin or 5 mm in one case) and the _PET-MRGTVs with margins of 10, 8, 5 and 3 mm.

Results

Seven recurrent glioma patients, who received PET-MRI prior to re-RT, were included into the present planning study. At the time of re-RT, patients were in median 54 years old and had a median Karnofsky Performance Status (KPS) score of 80. Median post-recurrence survival after the beginning of re-RT was 13 months. Concomitant bevacizumab therapy was applied in six patients and one patient received chemoradiation with temozolomide. Median GTV volumes of the three radiation oncologists were 35.0, 37.5 and 40.5 cubic centimeters (cc) and median _MRGTV volume 41.8 cc. Median BTV volume was 36.6 cc and median _PET-MRGTV volume 59.3 cc. The median Sørensen–Dice coefficient for the comparison between _MRGTV and BTV was 0.61 and the median conformity index 0.44. Recurrence pattern analysis revealed two central, two in-field and one distant recurrence within both, the original PTV, as well as the _PET-MRGTV with a reduced margin of 3 mm.

Conclusion

PET-MRI provides radiation treatment planning imaging with high spatial and timely conformity for high-grade glioma patients treated with re-RT with potential advancements for target volume delineation. Prospective randomised trials are warranted to further investigate the treatment benefits of PET-MRI based re-RT planning.

Reirradiation of recurrent high-grade glioma and development of prognostic scores for progression and survival

Background

Optimal techniques and patient selection for salvage reirradiation of high-grade glioma (HGG) are unclear. In this study, we identify prognostic factors for freedom from progression (FFP) and overall survival (OS) after reirradiation, risk factors for high-grade toxicity, and validate clinical prognostic scores.

Methods

A total of 116 patients evaluated between 2000 and 2018 received reirradiation for HGG (99 WHO grade IV, 17 WHO grade III). Median time to first progression after initial therapy was 10.6 months. Salvage therapies before reirradiation included surgery (31%) and systemic therapy (41%). Sixty-five patients (56%) received single-fraction stereotactic radiosurgery (SRS) as reirradiation. The median biologically effective dose (BED) was 47.25 Gy, and the median planning target volume (PTV) was 4.8 cc for SRS and 95.0 cc for non-SRS treatments. Systemic therapy was given concurrently to 52% and adjuvantly to 74% of patients.

Results

Median FFP was 4.9 months, and median OS was 11.0 months. Significant multivariable prognostic factors for FFP were performance status, time to initial progression, and BED; for OS they were age, time to initial progression, and PTV volume at recurrence. High-grade toxicity was correlated to PTV size at recurrence. Three-level prognostic scores were generated for FFP and OS, with cross-validated receiver operating characteristic area under the curve (AUC) of 0.640 and 0.687, respectively.

Conclusions

Clinical variables at the time of reirradiation for HGG can be used to prognosticate FFP and OS.

Hypofractionated Stereotactic Radiotherapy as a Salvage Therapy for Recurrent High-Grade Gliomas: Single-Center Experience

Background and Purpose:

The aim of this study was to investigate the survival outcomes and safety of hypofractioned stereotactic radiotherapy as a salvage treatment for recurrent high-grade glioma.

Patients and Methods:

Between March 2012 and March 2017, 32 consecutive patients (12 women, 20 men) treated in a single center were retrospectively included in this study. Grade III gliomas were diagnosed in 14 patients and grade IV in 18 patients. Thirty-four lesions were treated with hypofractionated stereotactic radiotherapy on a linear accelerator. Hypofractionated stereotactic radiotherapy delivered a median dose of 30 Gy (27-30) in 6 fractions (3-6) of 5 Gy (5-9). The treatment plans were normalized to 100% at the isocenter and prescribed to the 80% isodose line. Clinical outcomes and prognostic factors were analyzed.

Results:

Median follow-up was 20.9 months. Median overall survival following hypofractionated stereotactic radiotherapy was 15.6 months (median overall survival for patients with glioblastoma and grade III glioma was 8.2 and 19.5 months, respectively; P = .0496) and progression-free survival was 3.7 months (median progression-free survival for patients with glioblastoma and grade III glioma was 3.6 and 4.5 months, respectively; P = .2424). In multivariate analysis, tumor grade III (P = .0027), an Eastern Cooperative Oncology Group status <2 at the time of reirradiation (P = .0023), and a mean dose >35 Gy (P = .0055) significantly improved overall survival. A maximum reirradiation dose above 38 Gy (P = .0179) was significantly associated with longer progression-free survival.

Conclusion:

Hypofractionated stereotactic radiotherapy is well tolerated and offers an effective salvage option for the treatment of recurrent high-grade gliomas with encouraging overall survival. Our results suggest that the dose distribution had an impact on survival.

Conventionally fractionated stereotactic radiotherapy (CFRT) in combination with dose-dense temozolomide (TMZ) in relapsed malignant glioma: A case report

RATIONALE

At present, there is no uniform consensus on the treatment of recurrent glioblastoma, especially the re-irradiation dose and temozolomide (TMZ) dose. The literature on the treatment of recurrent glioblastoma (GBM) by conventionally fractionated stereotactic radiotherapy (CFRT) is even rarer.

PATIENT CONCERNS

A 44-year-old woman was admitted to our hospital for residual tumor after reoperation.

DIAGNOSES

Postoperative pathological diagnosis was GBM, WHO grade IV. The brain magnetic resonance imaging re-examination showed abnormal enhancement around the local operative region after resection of the left frontal lobe tumor, and there was presence of residual tumor.

INTERVENTIONS

The patient was treated with reoperation followed by re-irradiation plus dose-dense TMZ to achieve complete remission.

OUTCOMES

Complete remission was observed at the end of radiotherapy and at the 1 month follow-up after radiotherapy.

LESSONS

This study suggests that CFRT plus dose-dense TMZ might be a feasible option for the treatment in relapsed malignant glioma patients with good general condition.

Re-irradiation of recurrent glioblastoma as part of a sequential multimodality treatment concept

PURPOSE

The aim of this retrospective study was to evaluate survival outcomes in well-performing, mainly, young patients receiving a sequence of all available therapeutic options for relapsed glioblastoma, including re-irradiation.

METHODS

We performed a retrospective analysis of 27 patients irradiated twice for glioblastoma between 2008 and 2016. In the first line, all had surgical treatment of the tumor followed by radiotherapy with a total dose of 60 Gy and temozolomide. All re-irradiated patients were treated with a total dose of 36 Gy in 12 fractions. The endpoints were death from glioblastoma or any cause, and toxicity after re-irradiation.

RESULTS

The median follow-up of survivors was 35.6 months. At the time of analysis, 25 patients had died. The median time between first and second radiotherapy was 18.9 months (6.1-58.4). Re-irradiation was performed at different time points of first, second and third progression. The median overall survival after first diagnosis was 39.2 months. Five years after first surgery, nearly 20% of the patients were alive.

CONCLUSION

Carefully planned re-irradiation of the brain is a safe therapy for recurrent glioblastoma. Younger and well-performing patients benefit from all available therapy options. Every patient should be discussed in a multidisciplinary setting at each time point of tumor progression. Further prospective studies are needed to define the optimal time, dose and volume of re-irradiation.

CT-guided interstitial HDR-brachytherapy for recurrent glioblastoma multiforme: a 20-year single-institute experience

PURPOSE

To report our results of computed tomography-guided interstitial high-dose-rate (HDR) brachytherapy (BRT) in the treatment of patients with recurrent inoperable glioblastoma multiforme (GBM).

PATIENTS AND METHODS

Between 1995 and 2014, 135 patients were treated with interstitial HDR BRT for inoperable recurrent GBM located within previously irradiated volumes. Patient's median age was 57.1 years (14-82 years). All patients were pretreated with surgery, postoperative external beam radiation therapy (EBRT) and systemic chemotherapy (ChT). The median recurrent tumor volume was 42 cm³ (2-207 cm³). The prescribed HDR dose was median 40 Gy (30-50 Gy) delivered in twice-daily fractions of 5.0 Gy over consecutive days. No repeat surgery or ChT was administered in conjunction with BRT. Survival from BRT, progression-free survival (PFS), toxicity as well as the impact of several prognostic factors were evaluated.

RESULTS

At a median follow-up of 9.2 months, the median overall survival following BRT and the median PFS were 9.2 and 4.6 months, respectively. Of the prognostic variables evaluated in univariate analysis, extent of surgery at initial diagnosis, tumor volume at recurrence, as well as time from EBRT to BRT reached statistical significance, retained also in multivariate analysis. Eight patients (5.9%) developed treatment-associated complications including intracerebral bleeding in 4 patients (2.9%), symptomatic focal radionecrosis in 3 patients (2.2%), and severe convulsion in 1 patient (0.7%).

CONCLUSIONS

For patients with recurrent GBM, interstitial HDR BRT is an effective re-irradiation method for even larger tumors providing palliation without excessive toxicity.

Efficacy of Gamma Knife Radiosurgery for Recurrent High-Grade Gliomas with Limited Tumor Volume

Objective

This study aims to determine whether gamma knife radiosurgery (GKR) improves survival in patients with recurrent highgrade gliomas.

Methods

Twenty nine patients with recurrent high-grade glioma underwent 38 GKR. The male-to-female ratio was 10 : 19, and the median age was 53.8 years (range, 20-75). GKR was performed in 11 cases of recurrent anaplastic oligodendrogliomas, five anaplastic astrocytomas, and 22 glioblastomas. The median prescription dose was 16 Gy (range, 10-24), and the median target volume was 7.0 mL (range, 1.1-15.7). Of the 29 patients, 13 (44.8%) received concurrent chemotherapy. We retrospectively analyzed the progression-free survival (PFS) and overall survival (OS) after GKR depending on the Eastern Cooperative Oncology Group (ECOG) performance status (PS), pathology, concurrent chemotherapy, radiation dose, and target tumor volume.

Results

Starting from when the patients underwent GKR, the median PFS and OS were 5.0 months (range, 1.1-28.1) and 13.0 months (range, 1.1-75.1), respectively. On univariate analysis, the median PFS was significantly long in patients with anaplastic oligodendroglioma, ECOG PS 1, and target tumor volume less than 10 mL (p&lt;0.05). Meanwhile, on multivariate analysis, patients with ECOG PS 1 and target tumor volume less than 10 mL showed improved PFS (p=0.043 and p=0.007, respectively). The median OS was significantly increased in patients with ECOG PS 1 and tumor volume less than 10 mL on univariate and multivariate analyses (p&lt;0.05).

Conclusion

GKR could be an additional treatment option in recurrent high-grade glioma, particularly in patients with good PS and limited tumor volume.

Impact of 18F-FET PET on Target Volume Definition and Tumor Progression of Recurrent High Grade Glioma Treated with Carbon-Ion Radiotherapy

High-precision radiotherapy (HPR) of recurrent high grade glioma (HGG) requires accurate spatial allocation of these infiltrative tumors. We investigated the impact of ¹⁸F-FET PET on tumor delineation and progression of recurrent HGG after HPR with carbon ions. T₁ contrast enhanced MRI and ¹⁸F-FET-PET scans of 26 HGG patients were fused with radiotherapy planning volumes. PET-positive (PET+) tumor volumes using different isocontours (I%) were systematically investigated and compared with MRI-derived gross tumor volumes (GTV). Standardized uptake ratios (SUR) were further correlated with GTV and tumor progression patterns. In grade IV glioma, SUR > 2.92 significantly correlated with poor median overall survival (6.5 vs 13.1 months, p = 0.00016). We found no reliable SUR cut-off criteria for definition of PET+ volumes. Overall conformity between PET and MRI-based contours was low, with maximum conformities between 0.42–0.51 at I40%. The maximum sensitivity and specificity for PET+ volumes outside of GTV predicting tumor progression were 0.16 (I40%) and 0.52 (I50%), respectively. In 75% of cases, FLAIR hyperintense area covered over 80% of PET+ volumes. ¹⁸F-FET-PET derived SUR has a prognostic impact in grade IV glioma. The value of substantial mismatches between MRI-based GTV and PET+ volumes to improve tumor delineation in radiotherapy awaits further validation in randomized prospective trials.

A 4-miRNA signature predicts the therapeutic outcome of glioblastoma

Multimodal therapy of glioblastoma (GBM) reveals inter-individual variability in terms of treatment outcome. Here, we examined whether a miRNA signature can be defined for the a priori identification of patients with particularly poor prognosis.

FFPE sections from 36 GBM patients along with overall survival follow-up were collected retrospectively and subjected to miRNA signature identification from microarray data. A risk score based on the expression of the signature miRNAs and cox-proportional hazard coefficients was calculated for each patient followed by validation in a matched GBM subset of TCGA. Genes potentially regulated by the signature miRNAs were identified by a correlation approach followed by pathway analysis.

A prognostic 4-miRNA signature, independent of MGMT promoter methylation, age, and sex, was identified and a risk score was assigned to each patient that allowed defining two groups significantly differing in prognosis (p-value: 0.0001, median survival: 10.6 months and 15.1 months, hazard ratio = 3.8). The signature was technically validated by qRT-PCR and independently validated in an age- and sex-matched subset of standard-of-care treated patients of the TCGA GBM cohort (n=58). Pathway analysis suggested tumorigenesis-associated processes such as immune response, extracellular matrix organization, axon guidance, signalling by NGF, GPCR and Wnt. Here, we describe the identification and independent validation of a 4-miRNA signature that allows stratification of GBM patients into different prognostic groups in combination with one defined threshold and set of coefficients that could be utilized as diagnostic tool to identify GBM patients for improved and/or alternative treatment approaches.

Adjuvant stereotactic fractionated radiotherapy to the resection cavity in recurrent glioblastoma - the GlioCave study (NOA 17 - ARO 2016/3 - DKTK ROG trial)

Background

Glioblastoma relapses in the vast majority of cases within 1 year. Maximum safe resection of the recurrent glioblastoma can be offered in some cases. Re-irradiation has been established for the treatment of recurrent glioblastoma, too. In both cases, adjuvant treatment, mostly using temozolomide, can improve PFS and OS after these interventions. However, combining gross tumor resection and adjuvant re-radiotherapy to the resection cavity has not been tested so far.

Methods/Design

In the multicenter two-armed randomized Phase II GlioCave Study, fractionated stereotactic radiotherapy to the resection cavity, after gross tumor resection of recurrent glioblastoma, will be compared to observation. Depending on the size of the target volume, a total dose of 46 Gy in 2 Gy per fraction or a total dose if 36 Gy in 3 Gy per fraction will be applied. Progression free survival will be the primary endpoint of the study.

Discussion

Adjuvant treatment after gross tumor resection of recurrent glioblastoma is currently deemed to be limited to chemotherapy. However, re-irradiation has proven safety and tolerability in the treatment of macroscopic disease. Performing re-irradiation as an adjuvant measure after gross tumor resection has not been tested so far. The GlioCave Study will investigate the efficacy and the safety profile of this approach.

Trial registration

The trial was prospectively registered at clinicaltrials.gov (NCT02715297, registration date February 29th, 2016). The protocol presented hereby refers to the version 1.2 of the protocol (January 11^th, 2017).

Subventricular zone involvement at recurrence is a strong predictive factor of outcome following high grade glioma reirradiation

We aimed to assess the efficacy of stereotactic irradiation for patients with recurrent high-grade glioma (HGG) and identify predictive factors of progression-free survival (PFS) and overall survival (OS) following reirradiation. We identified 32 patients with recurrent brain HGG who had been treated with either single-dose (stereotactic radiosurgery) or fractionated stereotactic radiotherapy between April 2008 and October 2015. Median follow up was 21.4 months (range 12.9-23.2) and median PFS was and 3.3 months (95% CI [2.3-4.7]), respectively. OS was 90.40% (95% CI [73.09-96.80]) at 6 months and 79.55% (95% CI [59.9-90.29]) at 12 months. Univariate analysis showed that biological effective dose at isocenter ≤ 76 Gy was a poor prognostic factor for both OS (83.33 vs. 100% at 6 months, p = 0.032) and median PFS (2.7 vs. 4.7 months, p = 0.025), as was gross tumor volume (GTV) above 1 cm³ for OS (86.15 vs. 94.12% at 6 months, p = 0.043). Contact with the subventricular zone (SVZ) was also a poor prognostic factor for median PFS (2.3 vs. 4.7 months, p = 0.002). Multivariate analysis showed that SVZ contact remained a poor prognostic factor for PFS (hazard ratio = 3.44, 95% CI [1.21-9.82], p = 0.021). Results suggest that reirradiation is a safe and effective treatment option for recurrent HGG in patients with a good Karnosfsky Performance Scale score, a long progression-free interval since first radiation and limited GTV, and that contact to SVZ is a strong prognostic factor for PFS.

BICD1 expression, as a potential biomarker for prognosis and predicting response to therapy in patients with glioblastomas

There is variation in the survival and therapeutic outcome of patients with glioblastomas (GBMs). Therapy resistance is an important challenge in the treatment of GBM patients. The aim of this study was to identify Temozolomide (TMZ) related genes and confirm their clinical relevance. The TMZ-related genes were discovered by analysis of the gene-expression profiling in our cell-based microarray. Their clinical relevance was verified by in silico meta-analysis of the Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) datasets. Our results demonstrated that BICD1 expression could predict both prognosis and response to therapy in GBM patients. First, high BICD1 expression was correlated with poor prognosis in the TCGA GBM cohort (n=523) and in the CGGA glioma cohort (n=220). Second, high BICD1 expression predicted poor outcome in patients with TMZ treatment (n=301) and radiation therapy (n=405). Third, multivariable Cox regression analysis confirmed BICD1 expression as an independent factor affecting the prognosis and therapeutic response of TMZ and radiation in GBM patients. Additionally, age, MGMT and BICD1 expression were combinedly utilized to stratify GBM patients into more distinct risk groups, which may provide better outcome assessment. Finally, we observed a strong correlation between BICD1 expression and epithelial-mesenchymal transition (EMT) in GBMs, and proposed a possible mechanism of BICD1-associated survival or therapeutic resistance in GBMs accordingly. In conclusion, our study suggests that high BICD1 expression may result in worse prognosis and could be a predictor of poor response to TMZ and radiation therapies in GBM patients.

Prognostic factors for survival in adult patients with recurrent glioblastoma: a decision-tree-based model

We assessed prognostic factors in relation to OS from progression in recurrent glioblastomas. Retrospective multicentric study enrolling 407 (training set) and 370 (external validation set) adult patients with a recurrent supratentorial glioblastoma treated by surgical resection and standard combined chemoradiotherapy as first-line treatment. Four complementary multivariate prognostic models were evaluated: Cox proportional hazards regression modeling, single-tree recursive partitioning, random survival forest, conditional random forest. Median overall survival from progression was 7.6 months (mean, 10.1; range, 0-86) and 8.0 months (mean, 8.5; range, 0-56) in the training and validation sets, respectively (p = 0.900). Using the Cox model in the training set, independent predictors of poorer overall survival from progression included increasing age at histopathological diagnosis (aHR, 1.47; 95% CI [1.03-2.08]; p = 0.032), RTOG-RPA V-VI classes (aHR, 1.38; 95% CI [1.11-1.73]; p = 0.004), decreasing KPS at progression (aHR, 3.46; 95% CI [2.10-5.72]; p < 0.001), while independent predictors of longer overall survival from progression included surgical resection (aHR, 0.57; 95% CI [0.44-0.73]; p < 0.001) and chemotherapy (aHR, 0.41; 95% CI [0.31-0.55]; p < 0.001). Single-tree recursive partitioning identified KPS at progression, surgical resection at progression, chemotherapy at progression, and RTOG-RPA class at histopathological diagnosis, as main survival predictors in the training set, yielding four risk categories highly predictive of overall survival from progression both in training (p < 0.0001) and validation (p < 0.0001) sets. Both random forest approaches identified KPS at progression as the most important survival predictor. Age, KPS at progression, RTOG-RPA classes, surgical resection at progression and chemotherapy at progression are prognostic for survival in recurrent glioblastomas and should inform the treatment decisions.

Indications and Efficacy of Gamma Knife Stereotactic Radiosurgery for Recurrent Glioblastoma: 2 Decades of Institutional Experience

BACKGROUND

The role of stereotactic radiosurgery (SRS) for recurrent glioblastoma and the radionecrosis risk in this setting remain unclear.

OBJECTIVE

To perform a large retrospective study to help inform proper indications, efficacy, and anticipated complications of SRS for recurrent glioblastoma.

METHODS

We retrospectively analyzed patients who underwent Gamma Knife SRS between 1991 and 2013. We used the partitioning deletion/substitution/addition algorithm to identify potential predictor covariate cut points and Kaplan-Meier and proportional hazards modeling to identify factors associated with post-SRS and postdiagnosis survival.

RESULTS

One hundred seventy-four glioblastoma patients (median age, 54.1 years) underwent SRS a median of 8.7 months after initial diagnosis. Seventy-five percent had 1 treatment target (range, 1-6), and median target volume and prescriptions were 7.0 cm 3 (range, 0.3-39.0 cm 3 ) and 16.0 Gy (range, 10-22 Gy), respectively. Median overall survival was 10.6 months after SRS and 19.1 months after diagnosis. Kaplan-Meier and multivariable modeling revealed that younger age at SRS, higher prescription dose, and longer interval between original surgery and SRS are significantly associated with improved post-SRS survival. Forty-six patients (26%) underwent salvage craniotomy after SRS, with 63% showing radionecrosis or mixed tumor/necrosis vs 35% showing purely recurrent tumor. The necrosis/mixed group had lower mean isodose prescription compared with the tumor group (16.2 vs 17.8 Gy; P = .003) and larger mean treatment volume (10.0 vs 5.4 cm 3 ; P = .009).

CONCLUSION

Gamma Knife may benefit a subset of focally recurrent patients, particularly those who are younger with smaller recurrences. Higher prescriptions are associated with improved post-SRS survival and do not seem to have greater risk of symptomatic treatment effect.

Insights into molecular therapy of glioma: current challenges and next generation blueprint

Glioma accounts for the majority of human brain tumors. With prevailing treatment regimens, the patients have poor survival rates. In spite of current development in mainstream glioma therapy, a cure for glioma appears to be out of reach. The infiltrative nature of glioma and acquired resistance substancially restrict the therapeutic options. Better elucidation of the complicated pathobiology of glioma and proteogenomic characterization might eventually open novel avenues for the design of more sophisticated and effective combination regimens. This could be accomplished by individually tailoring progressive neuroimaging techniques, terminating DNA synthesis with prodrug-activating genes, silencing gliomagenesis genes (gene therapy), targeting miRNA oncogenic activity (miRNA-mRNA interaction), combining Hedgehog-Gli/Akt inhibitors with stem cell therapy, employing tumor lysates as antigen sources for efficient depletion of tumor-specific cancer stem cells by cytotoxic T lymphocytes (dendritic cell vaccination), adoptive transfer of chimeric antigen receptor-modified T cells, and combining immune checkpoint inhibitors with conventional therapeutic modalities. Thus, the present review captures the latest trends associated with the molecular mechanisms involved in glial tumorigenesis as well as the limitations of surgery, radiation and chemotherapy. In this article we also critically discuss the next generation molecular therapeutic strategies and their mechanisms for the successful treatment of glioma.

Bevacizumab and radiotherapy for the treatment of glioblastoma: brothers in arms or unholy alliance?

Glioblastoma (GBM) represents the most frequent primary brain tumor in adults and carries a dismal prognosis despite aggressive, multimodal treatment regimens involving maximal resection, radiochemotherapy, and maintenance chemotherapy. Histologically, GBMs are characterized by a high degree of VEGF-mediated vascular proliferation. In consequence, new targeted anti-angiogenic therapies, such as the monoclonal anti-VEGF-A antibody bevacizumab, have proven effective in attenuating tumor (neo)angiogenesis and were shown to possess therapeutic activity in several phase II trials. However, the role of bevacizumab in the context of multimodal therapy approaches appears to be rather complex. This review will give insights into current concepts, limitations, and controversies regarding the molecular mechanisms and the clinical benefits of bevacizumab treatment in combination with radio(chemo)therapy - particularly in face of the results of recent phase III trials, which failed to demonstrate convincing improvements in overall survival (OS).

Cytotoxicity of trans-chalcone and licochalcone A against breast cancer cells is due to apoptosis induction and cell cycle arrest

Chalcones are precursors of flavonoids that exhibit structural heterogeneity and potential antitumor activity. The objective of this study was to characterize the cytotoxicity of trans-chalcone and licochalcone A (LicoA¹) against a breast cancer cell line (MCF-7) and normal murine fibroblasts (3T3). Also the mechanisms of the anti-cancer activity of these two compounds were studied. The alkaline comet assay revealed dose-dependent genotoxicity, which was more responsive against the tumor cell line, compared to the 3T3 mouse fibroblast cell line. Flow cytometry showed that the two chalcones caused the cell cycle arrest in the G1 phase and induced apoptosis in MCF-7 cells. Using PCR Array, we found that trans-chalcone and LicoA trigger apoptosis mediated by the intrinsic pathway as demonstrated by the inhibition of Bcl-2 and induction of Bax. In western blot assay, the two chalcones reduced the expression of cell death-related proteins such as Bcl-2 and cyclin D1 and promoted the cleavage of PARP. However, only trans-chalcone induced the expression of the CIDEA gene and protein in these two experiments. Furthermore, transient transfections of MCF-7 using a construction of a promoter-luciferase vector showed that trans-chalcone induced the expression of the CIDEA promoter activity in 24 and 48h. In conclusion, the results showed that trans-chalcone promoted high induction of the CIDEA promoter gene and protein, which is related to DNA fragmentation during apoptosis.

Tumor Metabolism, the Ketogenic Diet and β-Hydroxybutyrate: Novel Approaches to Adjuvant Brain Tumor Therapy

Malignant brain tumors are devastating despite aggressive treatments such as surgical resection, chemotherapy and radiation therapy. The average life expectancy of patients with newly diagnosed glioblastoma is approximately ~18 months. It is clear that increased survival of brain tumor patients requires the design of new therapeutic modalities, especially those that enhance currently available treatments and/or limit tumor growth. One novel therapeutic arena is the metabolic dysregulation that results in an increased need for glucose in tumor cells. This phenomenon suggests that a reduction in tumor growth could be achieved by decreasing glucose availability, which can be accomplished through pharmacological means or through the use of a high-fat, low-carbohydrate ketogenic diet (KD). The KD, as the name implies, also provides increased blood ketones to support the energy needs of normal tissues. Preclinical work from a number of laboratories has shown that the KD does indeed reduce tumor growth in vivo. In addition, the KD has been shown to reduce angiogenesis, inflammation, peri-tumoral edema, migration and invasion. Furthermore, this diet can enhance the activity of radiation and chemotherapy in a mouse model of glioma, thus increasing survival. Additional studies in vitro have indicated that increasing ketones such as β-hydroxybutyrate (βHB) in the absence of glucose reduction can also inhibit cell growth and potentiate the effects of chemotherapy and radiation. Thus, while we are only beginning to understand the pluripotent mechanisms through which the KD affects tumor growth and response to conventional therapies, the emerging data provide strong support for the use of a KD in the treatment of malignant gliomas. This has led to a limited number of clinical trials investigating the use of a KD in patients with primary and recurrent glioma.

Targeted therapies for the treatment of non-small-cell lung cancer: Monoclonal antibodies and biological inhibitors

The usual treatments for patients with non-small-cell lung cancer (NSCLC), such as advanced lung adenocarcinoma, are unspecific and aggressive, and include lung resection, radiotherapy and chemotherapy. Recently, treatment with monoclonal antibodies and biological inhibitors has emerged as an effective alternative, generating effective results with few side effects. In recent years, several clinical trials using monoclonal antibodies presented potential benefits to NSCLC, and 4 of them are already approved for the treatment of NSCLC, such as cetuximab, bevacizumab, nivolumab and pembrolizumab. Also, biological inhibitors are attractive tolls for biological applications. Among the approved inhibitors are crizotinib, erlotinib, afatinib and gefitinib, and side effects are usually mild to intense. Nevertheless, biological molecule treatments are under development, and several new monoclonal antibodies and biological inhibitors are in trial to treat NSCLC. Also under trial study are as follows: anti-epidermal growth factor receptor (EGFR) antibodies (nimotuzumab and ficlatuzumab), anti-IGF 1 receptor (IGF-1R) monoclonal antibody (figitumumab), anti-NR-LU-10 monoclonal antibody (nofetumomab) as well as antibodies directly affecting the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) molecule (ipilimumab and tremelimumab), to receptor activator of nuclear factor-kappa B ligand (RANKL) (denosumab) or to polymerase enzyme (veliparib and olaparib). Among new inhibitors under investigation are poly-ADP ribose polymerase (PARP) inhibitors (veliparib and olaparib) and phosphatidylinositol 3-kinase (PI3K) inhibitor (buparlisib). However, the success of immunotherapies still requires extensive research and additional controlled trials to evaluate the long-term benefits and side effects.

Role of PHLPP1 in inflammation response: Its loss contributes to gliomas development and progression

PH domain leucine-rich repeats protein phosphatase 1(PHLPP1) belongs to a novel family of Ser/Thr protein phosphatases: PHLPP serves as tumor suppressor in several cancers. However, little knowledge about the expression of PHLPP1 in human glioma tumor tissue and its role in inflammation response in glioma cells was known. Glioma samples were obtained from a total of 37 patients including 16 males and 21 females with surgical removal of the brain tumor. PHLPP1 protein and inflammatory cytokines were measured by Western blot analysis and immunohistochemistry while mRNA was determined by RT-PCR. The levels of inflammatory cytokines including TNF-α, IL-17, IL-1β in U251 glioma cells were evaluated by siRNA PHLPP1 and PHLPP1 addition. The loss of PHLPP1 expression occurs at high frequency in human gliomas. The highest mean values of PHLPP1 mRNA and protein were found in non-glioma brain tissues whereas the lowest mean values were found in those in glioblastoma with an increase of TNF-α, IL-17, IL-1β (p<0.05). PHLPP1 expression in human glioma was associated negatively with the severity of the tumor and inflammatory cytokines. siRNA PHLPP1 could increase the levels of inflammatory cytokines in U251 glioma cells while PHLPP1 addition could inhibit significantly inflammatory cytokines. We concluded that PHLPP1 played a suppression role in inflammatory response of glioma. The present study indicated that PHLPP1 could be used as a predictor for the prediction of the patients or as a therapeutic target for the treatment of human glioma.

Complete resection of contrast-enhancing tumor volume is associated with improved survival in recurrent glioblastoma-results from the DIRECTOR trial

BACKGROUND

The role of reoperation for recurrent glioblastoma (GBM) remains unclear. Prospective studies are lacking. Here, we studied the association of clinical outcome with extent of resection upon surgery for recurrent GBM in the patient cohort of DIRECTOR, a prospective randomized multicenter trial comparing 2 dose-intensified temozolomide regimens at recurrence of GBM.

METHODS

We analyzed prospectively collected clinical and imaging data from the DIRECTOR cohort (N = 105). Volumetric analysis was performed on gadolinium contrast-enhanced MRI as well as fluid attenuated inversion recovery/T2 MRI and correlated with PFS after initial progression (PFS2) and post-recurrence survival (PRS). Quality of life was monitored by the EORTC QLQ-C30 and QLQ-BN20 questionnaires at 8-week intervals.

RESULTS

Seventy-one patients received surgery at first recurrence. Prognostic factors, including age, MGMT promoter methylation, and Karnofsky performance score, were balanced between patients with and without reoperation. Outcome in patients with versus without surgery at recurrence was similar for PFS2 (2.0 mo vs 1.9 mo, P = .360) and PRS (11.4 mo vs 9.8 mo, P = .633). Among reoperated patients, post-surgery imaging was available in 59 cases. In these patients, complete resection of contrast-enhancing tumor (N = 40) versus residual detection of contrast enhancement (N = 19) was associated with improved PRS (12.9 mo [95% CI: 11.5-18.2] vs 6.5 mo [95% CI: 3.6-9.9], P < .001) and better quality of life. Incomplete tumor resection was associated with inferior PRS compared with patients who did not undergo surgery (6.5 vs 9.8 mo, P = .052). Quality of life was similar in these 2 groups.

CONCLUSION

Surgery at first recurrence of GBM improves outcome if complete resection of contrast-enhancing tumor is achieved.

MiR-338-5p sensitizes glioblastoma cells to radiation through regulation of genes involved in DNA damage response

Glioblastoma multiforme (GBM) is the most aggressive form of brain tumor. Despite radical surgery and radiotherapy supported by chemotherapy, the disease still remains incurable with an extremely low median survival rate of 12-15 months from the time of initial diagnosis. The main cause of treatment failure is considered to be the presence of cells that are resistant to the treatment. MicroRNAs (miRNAs) as regulators of gene expression are involved in the tumor pathogenesis, including GBM. MiR-338 is a brain-specific miRNA which has been described to target pathways involved in proliferation and differentiation. In our study, miR-338-3p and miR-338-5p were differentially expressed in GBM tissue in comparison to non-tumor brain tissue. Overexpression of miR-338-3p with miRNA mimic did not show any changes in proliferation rates in GBM cell lines (A172, T98G, U87MG). On the other hand, pre-miR-338-5p notably decreased proliferation and caused cell cycle arrest. Since radiation is currently the main treatment modality in GBM, we combined overexpression of pre-miR-338-5p with radiation, which led to significantly decreased cell proliferation, increased cell cycle arrest, and apoptosis in comparison to irradiation-only cells. To better elucidate the mechanism of action, we performed gene expression profiling analysis that revealed targets of miR-338-5p being Ndfip1, Rheb, and ppp2R5a. These genes have been described to be involved in DNA damage response, proliferation, and cell cycle regulation. To our knowledge, this is the first study to describe the role of miR-338-5p in GBM and its potential to improve the sensitivity of GBM to radiation.

Outcome and toxicity profile of salvage low-dose-rate iodine-125 stereotactic brachytherapy in recurrent high-grade gliomas

BACKGROUND

The aim of this study was to provide an outcome and toxicity profile of salvage low-dose-rate iodine-125 (I-125) stereotactic brachytherapy (SBT) in patients with small, circumscribed malignant glioma recurrences.

METHODS

Patients with malignant glioma recurrences consecutively undergoing salvage SBT from 2003 to 2011 were identified from our prospective tumor database. SBT was considered a potentially suitable treatment strategy for adult mostly multimodally pretreated patients (Karnofsky score of ≥ 70) with biopsy-proven, circumscribed, small (diameter ≤ 3.5 cm) recurrences. Exclusively temporary I-125 seeds were used (reference dose: 50 Gy, dose rate: < 15 cGy/h). Study endpoints were time-to-treatment failure (TTF) after SBT, postrecurrence survival (PRS), and toxicity. Survival was assessed with the Kaplan-Meier method. Adverse events were categorized according to the RTOG/EORTC classification. Prognostic factors were obtained from proportional hazards models.

RESULTS

Sixty-eight patients (28 WHO grade III, 40 WHO grade IV gliomas) were included. Fifty-nine patients had previously received external beam radiation. Median TTF and PRS were 8.3 months and 13.4 months, respectively. TTF and PRS were longer for grade III gliomas than for glioblastomas (15.0 vs. 6.2 months and 28.1 vs. 9.3 months, respectively). Patients with grade III tumors were younger (p = 0.002). Favorable factors for TTF and PRS were age ≤ 50 years and a methylated O(6)-methylguanine-DNA methyltransferase (MGMT)-promoter. Alternative models including tumor grade instead of age reached a similar good fit. Three patients suffered from grade I, one from grade II, and two from grade IV toxicity.

CONCLUSIONS

Salvage SBT is feasible and safe even after previously performed external beam radiation. Favorable outcome measurements in particular for grade III recurrences deserve further prospective evaluation.