Co-infection of two eukaryotic pathogens within clam populations in Arcachon Bay

The parasitic species Perkinsus olseni (= atlanticus) (Perkinsea, Alveolata) infects a wide range of mollusc species and is responsible for mortality events and economic losses in the aquaculture industry and fisheries worldwide. Thus far, most studies conducted in this field have approached the problem from a "one parasite-one disease" perspective, notably with regards to commercially relevant clam species, while the impact of other Perkinsus species should also be considered as it could play a key role in the disease phenotype and dynamics. Co-infection of P. olseni and P. chesapeaki has already been sporadically described in Manila clam populations in Europe. Here, we describe for the first time the parasitic distribution of two Perkinsus species, P. olseni and P. chesapeaki, in individual clam organs and in five different locations across Arcachon Bay (France), using simultaneous in situ detection by quantitative PCR (qPCR) duplex methodology. We show that P. olseni single-infection largely dominated prevalence (46-84%) with high intensities of infection (7.2 to 8.5 log-nb of copies. g-1of wet tissue of Manila clam) depending on location, suggesting that infection is driven by the abiotic characteristics of stations and physiological states of the host. Conversely, single P. chesapeaki infections were observed in only two sampling stations, Ile aux Oiseaux and Gujan, with low prevalences 2 and 14%, respectively. Interestingly, the co-infection by both Perkinsus spp., ranging in prevalence from 12 to 34%, was distributed across four stations of Arcachon Bay, and was detected in one or two organs maximum. Within these co-infected organs, P. olseni largely dominated the global parasitic load. Hence, the co-infection dynamics between P. olseni and P. chesapeaki may rely on a facilitating role of P. olseni in developing a primary infection which in turn may help P. chesapeaki infect R. philippinarum as a reservoir for a preferred host. This ecological study demonstrates that the detection and quantification of both parasitic species, P. olseni and P. chesapeaki, is essential and timely in resolving cryptic infections and their consequences on individual hosts and clam populations.

Human brain mapping using co-registered fUS, fMRI and ESM during awake brain surgeries: A proof-of-concept study

Accurate, depth-resolved functional imaging is key in both understanding and treatment of the human brain. A new sonography-based imaging technique named functional Ultrasound (fUS) uniquely combines high sensitivity with submillimeter-subsecond spatiotemporal resolution available in large fields-of-view. In this proof-of-concept study we show that: (A) fUS reveals the same eloquent regions as found by fMRI while concomitantly visualizing in-vivo microvascular morphology underlying these functional hemodynamics and (B) fUS-based functional maps are confirmed by Electrocortical Stimulation Mapping (ESM), the current gold-standard in awake neurosurgical practice. This unique cross-modality experiment was performed using motor, visual and language-related functional tasks in patients undergoing awake brain tumor resection. The current work serves as an important milestone towards further maturity of fUS as well as a novel avenue to increase our understanding of hemodynamics-based functional brain imaging.

Responsible design and implementation of technologies for the prevention of infectious diseases: towards a values-based assessment framework for the Dutch government

OBJECTIVES

The Dutch government implemented the apps 'CoronaMelder' and 'CoronaCheck' to prevent the transmission of SARS-CoV-2. They faced many questions on how to responsibly implement such technologies. Here, we aim to develop an assessment framework to support the Dutch national government with the responsible design and implementation of technologies for the prevention of future infectious diseases.

STUDY DESIGN

Three-stage web-based Delphi process.

METHODS

The assessment framework was developed through two research phases. During the Initial Design phase, a conceptual version of the assessment framework was developed through a scoping review and semistructured interviews with a scientific board. The Consensus phase involved a three-stage web-based Delphi process with an expert community.

RESULTS

The final assessment framework consists of five development phases, 10 values, and a total of 152 questions.

CONCLUSIONS

Technology assessment frameworks help policymakers to make informed decisions and contribute to the responsible implementation of technologies in society. The framework is now available for the Dutch government and other stakeholders to use in future pandemics. We discuss the possibilities of using the framework transnationally.

Association of pre-radiotherapy tumour burden and overall survival in newly diagnosed glioblastoma adjusted for MGMT promoter methylation status

PURPOSE

We retrospectively evaluated the association between postoperative pre-radiotherapy tumour burden and overall survival (OS) adjusted for the prognostic value of O6-methylguanine DNA methyltransferase (MGMT) promoter methylation in patients with newly diagnosed glioblastoma treated with radio-/chemotherapy with temozolomide.

MATERIALS AND METHODS

Patients were included from the CENTRIC (EORTC 26071-22072) and CORE trials if postoperative magnetic resonance imaging scans were available within a timeframe of up to 4weeks before radiotherapy, including both pre- and post-contrast T1w images and at least one T2w sequence (T2w or T2w-FLAIR). Postoperative (residual) pre-radiotherapy contrast-enhanced tumour (CET) volumes and non-enhanced T2w abnormalities (NT2A) tissue volumes were obtained by three-dimensional segmentation. Cox proportional hazard models and Kaplan Meier estimates were used to assess the association of pre-radiotherapy CET/NT2A volume with OS adjusted for known prognostic factors (age, performance status, MGMT status).

RESULTS

408 tumour (of which 270 MGMT methylated) segmentations were included. Median OS in patients with MGMT methylated tumours was 117 weeks versus 61weeks in MGMT unmethylated tumours (p < 0.001). When stratified for MGMT methylation status, higher CET volume (HR 1.020; 95% confidence interval CI [1.013-1.027]; p < 0.001) and older age (HR 1.664; 95% CI [1.214-2.281]; p = 0.002) were significantly associated with shorter OS while NT2A volume and performance status were not.

CONCLUSION

Pre-radiotherapy CET volume was strongly associated with OS in patients receiving radio-/chemotherapy for newly diagnosed glioblastoma stratified by MGMT promoter methylation status.

Impaired reproduction, energy reserves and dysbiosis: The overlooked consequences of heatwaves in a bivalve mollusc

Extreme events like Marine Heatwaves (MHWs) are becoming more intense, severe, and frequent, threatening benthic communities, specifically bivalves. However, the consequences of non-lethal MHWs on animals are still poorly understood. Here, we exposed the Manila clam Ruditapes philippinarum to non-lethal MHW for 30 days and provided an integrative view of its effects. Our result indicated that albeit non-lethal, MHW reduced clam's energy reserves (by reducing their hepato-somatic index), triggered antioxidant defenses (particularly in males), impaired reproduction (via the production of smaller oocytes in females), triggered dysbiosis in the digestive gland microbiota and altered animals' behaviour (by impacting their burying capacity) and filtration rate. Such effects were seen also at RNA-seq (i.e. many down-regulated genes belonged to reproduction) and metabolome level. Interestingly, negative effects were more pronounced in males than in females. Our results show that MHWs influence animal physiology at multiple levels, likely impacting its fitness and its ecosystem services.

Multidisciplinary long-term survey of Manila clam grown in farming sites subjected to different environmental conditions

In recent years recurrent bivalve mass mortalities considerably increased around the world, causing the collapse of natural and farmed populations. Venice Lagoon has historically represented one of the major production areas of the Manila clam Ruditapes philippinarum in Europe. However, in the last 20 years a 75 % decrease in the annual production has been experienced. While climate change and anthropogenic interventions may have played a key role in natural and farmed stocks reductions, no studies investigated at multiple levels the environmental stressors affecting farmed Manila clam to date. In this work we carried out a long-term monitoring campaign on Manila clam reared in four farming sites located at different distances from the southern Venice Lagoon inlet, integrating (meta)genomic approaches (i.e. RNA-seq; microbiota characterization), biometric measurements and chemical-physical parameters. Our study allowed to characterize the molecular mechanisms adopted by this species to cope with the different environmental conditions characterizing farming sites and to propose hypotheses to explain mortality events observed in recent years. Among the most important findings, the disruption of clam's immune response, the spread of Vibrio spp., and the up-regulation of molecular pathways involved in xenobiotic metabolism suggested major environmental stressors affecting clams farmed in sites placed close to Chioggia's inlet, where highest mortality was also observed. Overall, our study provides knowledge-based tools for managing Manila clam farming on-growing areas. In addition, the collected data is a snapshot of the time immediately before the commissioning of MoSE, a system of mobile barriers aimed at protecting Venice from high tides, and will represent a baseline for future studies on the effects of MoSE on clams farming and more in general on the ecology of the Venice Lagoon.

Multi-tissue RNA-Seq Analysis and Long-read-based Genome Assembly Reveal Complex Sex-specific Gene Regulation and Molecular Evolution in the Manila Clam

The molecular factors and gene regulation involved in sex determination and gonad differentiation in bivalve molluscs are unknown. It has been suggested that doubly uniparental inheritance (DUI) of mitochondria may be involved in these processes in species such as the ubiquitous and commercially relevant Manila clam, Ruditapes philippinarum. We present the first long-read-based de novo genome assembly of a Manila clam, and a RNA-Seq multi-tissue analysis of 15 females and 15 males. The highly contiguous genome assembly was used as reference to investigate gene expression, alternative splicing, sequence evolution, tissue-specific co-expression networks, and sexual contrasting SNPs. Differential expression (DE) and differential splicing (DS) analyses revealed sex-specific transcriptional regulation in gonads, but not in somatic tissues. Co-expression networks revealed complex gene regulation in gonads, and genes in gonad-associated modules showed high tissue specificity. However, male gonad-associated modules showed contrasting patterns of sequence evolution and tissue specificity. One gene set was related to the structural organization of male gametes and presented slow sequence evolution but high pleiotropy, whereas another gene set was enriched in reproduction-related processes and characterized by fast sequence evolution and tissue specificity. Sexual contrasting SNPs were found in genes overrepresented in mitochondrial-related functions, providing new candidates for investigating the relationship between mitochondria and sex in DUI species. Together, these results increase our understanding of the role of DE, DS, and sequence evolution of sex-specific genes in an understudied taxon. We also provide resourceful genomic data for studies regarding sex diagnosis and breeding in bivalves.

The meaning of screening: detection of brain metastasis in the adjuvant setting for stage III melanoma

BACKGROUND

The incidence of melanoma is increasing and 37% of patients with metastatic melanoma eventually have brain metastasis (BM). Currently, there is no consensus on screening for BM in patients with resected stage III melanoma. However, given the high incidence of BM, routine screening magnetic resonance imaging (MRI) of the brain is considered in patients with completely resected stage III melanoma before the start of adjuvant treatment. The aim of this study was to assess the yield of screening for BM in these patients.

MATERIALS AND METHODS

A single-center cohort study was carried out in the Erasmus MC, Rotterdam, The Netherlands, a large tertiary referral center for patients with melanoma. Eligible patients with complete resection of stage III melanoma and a screening MRI of the brain, made within 12 weeks after resection and before adjuvant treatment (programmed cell death protein 1 inhibitors, dabrafenib-trametinib), available between 1 August 2018 and 1 January 2021, were included.

RESULTS

A total of 202 patients were included. Eighteen (8.9%) of 202 patients had extracranial metastasis at screening. Two (1.1%) of the remaining 184 patients had BM at screening, resulting in a switch from adjuvant treatment to ipilimumab-nivolumab. At a median follow-up of 21.2 months, BM was detected in another 4 (2.4%) of 166 patients who started with adjuvant treatment.

CONCLUSIONS

The yield of screening MRI of the brain is low after complete resection of stage III melanoma, before the start of adjuvant treatment. Therefore, routine screening MRI is not recommended in this setting.

P05.04.A Disconcordance between different molecular methods to assess homozygous deletion of theCDKN2A/B locus in IDH-mutant astrocytomas

Background

The fifth edition of the WHO Classification of Tumors of the Central Nervous System (WHO CNS 5), includes molecular parameters for both diagnosis and grading in addition to histological features. For IDH-mutant astrocytoma, homozygous deletion (HD) of CDKN2A/B now results in WHO grade 4, even in the absence of microvascular proliferation or necrosis. CDKN2A/B deletions can be determined by various techniques including shallow and targeted sequencing, and using genome wide DNA-methylation arrays. Various algorithms to call deletions also exist for each platform. Concordance between the various techniques and algorithms is however unknown. Because of the importance to properly call CDKN2A/B deletions, we compared two techniques to call HD in IDH-mutant astrocytoma patients.

Methods

Samples from 110 IDH-mutant astrocytoma patients enrolled in the GLASS-NL study, and therefore samples from at least two surgical resections per patient, were available. Overall survival (OS) was measured from date of first surgery.

Both DNA-methylation data and shallow whole-genome sequencing (sWGS) was collected from 219 samples from 101 patients. For DNA-methylation analysis, HD of CDKN2A/B was defined by &lt;-0.6 log2 intensity combined with visual assessment on samples with log2 intensity between -0.6 and -0.2 (method 1), or by using a hard cutoff of &lt;-0.415 log2 intensity, as determined by Shirahata et al. (method 2). Absolute copy number profiles were estimated by ACE from sWGS data, HD of CDKN2A/B was defined by a loss of at least 1.2 CDKN2A alleles (method 3). Agreement score and Cohen’s kappa (κ) as an index for interrater agreement was calculated.

Results

Method 1 and method 2 called an HD of CDKN2A/B in 39 and 33 cases, respectively; method 1 called an HD of CDKN2A/B in 9 cases in which method 2 did not detect an alteration. The agreement was strong with 95% agreement and κ = 0.842.

Method 3 called an HD of CDKN2A/B in 45 cases of which 12 and 19 were not detected by method 1 and method 2 respectively. Method 3 showed an almost perfect level of agreement with method 1, with 97% agreement and κ = 0.911, and a moderate agreement with method 2, with 89% agreement and κ = 0.671.

Survival analysis showed that there was no significant difference in survival when patients were stratified by CDKN2A/B status of the initial sample of all methods. However, when stratified by CDKN2A/B status of the first recurrence, all methods showed a stronger association with OS (method 1: p = 0.001, HR = 2.61[1.44-4.72]; method 2: p = 0.0024, HR = 2.34[1.33-4.11]; method 3: p = 0.0099, HR = 2.34[1.2-4.55]).

Conclusion

Different methods and different cutoffs to determine the presence of a HD in CDKN2A/B may result in different test outcomes. Quality of the DNA, tumor cell percentage of the sample and ploidy are likely to influence the call of homozygous CDKN2A/B deletion. Ring tests are recommended to improve reliability.

OS08.1.A Integrative molecular analysis of matched primary and recurrent IDH-mutant astrocytoma; an update from the GLASS-NL consortium

Background

The evolutionary processes that drive tumor progression in patients with IDH-mutant astrocytoma remain largely unclear. The GLASS-NL consortium was initiated to gain insight into the molecular mechanisms underlying glioma evolution and to identify markers of progression in IDH-mutant astrocytomas. Ultimately, such markers can assist clinical decision making. Here, we present the DNA methylation profiling, RNA-sequencing and shallow whole-genome sequencing (sWGS) of samples included in the GLASS-NL study.

Methods

Eligible were patients with an IDH-mutant, 1p19q non-codeleted, astrocytoma at first diagnosis who underwent surgical resection of the tumor at least twice separated by &gt;6 months, and of whom paired tumor samples were available for analyses. Overall survival (OS) was measured from date of initial surgery.

DNA methylation profiling was performed with the 850kEPIC array, and transcriptome and sWGS by NGS. After quality control, DNA methylation data of 103, expression data of 91, and sWGS data of 92 patients was available for further analysis. Methylation classes were determined according to Capper et al. and copy number alterations (CNAs) were extracted from both sWGS and DNA-methylation data.

Results

110 patients were identified from various medical centers in the Netherlands. The median time between surgical resections was 41.9 months (IQR:26.5-65.9) and after initial surgery, 63% and 22% of the patients were treated with radiotherapy or chemotherapy respectively. The proportion of samples assigned to the high grade methylation class increased ~three-fold at recurrence. 83% of patients that progressed from low to high grade, received treatment prior to recurrent surgery, as compared to 53% of the patients that remained low grade.

Genome wide DNA methylation levels of recurrent samples were lower than that of initial samples. This difference is explained by the increased number of high grades at recurrence, since near identical DNA methylation levels were observed in samples that remained low grade.

Analysis of CNAs revealed chromosomal arms that were more frequently altered in high grade samples. Univariate analysis showed that losses in 3p, 9p, 10q, 13q and 14q were associated with poor OS.

More than 800 differentially expressed genes between initial and recurrent tumor samples were found. Chromosomal enrichment analysis revealed a locus on chromosome 6 enriched with histone genes, to be significantly up-regulated over time.

Conclusion

Longitudinal methylation profiling of IDH-mutant astrocytoma reveals a shift towards a higher grade at tumor recurrence coinciding with reduced DNA methylation levels, and increased frequency of CNAs. Longitudinal expression analysis showed changes in expression of &gt;800 genes, including an up-regulated locus enriched with histone genes. Further integrative analyses are ongoing and will be reported at the meeting.

P11.69.B IDH1/2wildtype gliomas grade 2 and 3 with molecular glioblastoma-like profile have a distinct course of epilepsy compared toIDH1/2wildtype glioblastomas

Background

IDH1/2 wildtype (IDHwt) glioma WHO grade 2 and 3 patients with pTERT mutation and/or EGFR amplification and/or +7/−10 chromosome gain/loss have a similar overall survival time as IDHwt glioblastoma patients, and are both considered glioblastoma IDHwt according to the WHO 2021 classification. However, differences in seizure onset have been observed. This study aimed to compare the course of epilepsy in the two glioblastoma subtypes.

Material and Methods

We analyzed epilepsy data of an existing cohort including IDHwt histologically lower-grade glioma WHO grade 2 and 3 with molecular glioblastoma-like profile (IDHwt hLGG) and IDHwt glioblastoma patients. Primary outcome was the incidence proportion of epilepsy during the disease course. Major secondary outcomes included onset of epilepsy, number of seizure days and antiepileptic drug (AED) polytherapy.

Results

Out of 254 patients, 78% (50/64) IDHwt hLGG and 68% (129/190) IDHwt glioblastoma patients developed epilepsy during the disease course (p=0.121). Epilepsy onset before histopathological diagnosis occurred more frequently in IDHwt hLGG compared to IDHwt glioblastoma patients (90% versus 60%, p&lt;0.001), with a significantly longer median time to diagnosis (3.5 versus 1.3 months, p&lt;0.001). Median total seizure days was also longer for IDHwt hLGG patients (7.0 versus 3.0, p=0.005), and they received more often AED polytherapy (32% versus 17%, p=0.028).

Conclusion

Although the incidence proportion of epilepsy during the entire disease course is similar, IDHwt hLGG patients show a significantly higher incidence of epilepsy before diagnosis and a significantly longer median time between first seizure and diagnosis compared to IDHwt glioblastoma patients, indicating a distinct clinical course.

P15.06.B Influence of arterial transit time delays on the differentiation between tumor progression and pseudo-progression in glioblastoma by arterial spin labeling MRI

Background

Perfusion MRI by Arterial Spin Labeling (ASL) and Dynamic Susceptibility Contrast (DSC) has shown its potential for differentiating tumor progression from pseudo-progression in glioblastoma patients. The ASL scans can be affected by arterial transit time (ATT) delays, which could be caused by treatment effects due to concomitant radiochemotherapy. A prolonged ATT is present as apparent signal increase in the large arteries due to labeled spins still residing within the vasculature, leading to underestimation of tissue perfusion and thus potentially affecting clinical decision-making. The research questions were: 1) Do delayed ATTs lead to a difference in the visual assessment of ASL perfusion (normal/increased) maps compared to DSC-MRI?; 2) Does the radiological evaluation (progression vs. pseudo-progression) of ASL and DSC perfusion maps differ when ATT artifacts are present?; 3) Do delayed ATTs affect the predictive value of ASL-MRI scans 3 months post-radiotherapy for detecting true disease progression?

Material and Methods

This retrospective, single-center study included 68 adult patients with histologically confirmed glioblastoma who received postoperative radio(chemo)therapy. ASL and DSC scans were acquired 3 months post-radiotherapy as part of routine clinical follow-up. The perfusion data were visually scored by a neuroradiologist who determined presence/absence of ATT artifacts and their severity (%), perfusion of the enhancing tumor lesion and the radiological evaluation of tumor progression versus pseudo-progression. Presence of true disease progression was determined by follow-up of clinical data until 9 months post-radiotherapy available for 49/68 patients. Logistic regression was performed with gender, age, treatment type and tumor genetic status as covariates to assess the predictive value of ASL.

Results

In 78% of the patients ATT artifacts were present. No statistically significant association between the agreement of the perfusion maps and presence of ATT artifacts was found, but presence of ATT artifacts lowered the agreement between the DSC and ASL radiological evaluation. The logistic regression analysis showed that the ASL-based radiological score could not predict true disease progression, whereas higher age and unmethylated MGMT gene were associated with progression. Presence of ATT artifacts was not associated with tumor progression.

Conclusion

The presence of delayed ATT in ASL data seems to impact the radiological evaluation of ASL data, steering interpretation towards tumor progression (as compared to the DSC evaluation), whereas in patients without ATT artifacts ASL and DSC provide more similar radiological scores. Therefore, it is highly recommended to consider these artifacts when interpreting ASL perfusion MRI to differentiate between tumor progression and pseudo-progression in glioblastoma patients.

P17.19.B Incidence of treatment-associated imaging changes in newly diagnosed MGMT promoter-methylated glioblastoma treated with cilengitide (EORTC 26071 - CENTRIC study): interim analysis

Background

In patients with glioblastoma, radiological recurrence of enhancing tissue after chemoradiotherapy can originate from progressive disease (PD) or from pseudoprogression/treatment-associated changes. There are no widely approved consensus criteria for treatment-associated changes. In the randomised EORTC-CENTRIC study (NCT00689221), patients with MGMT promoter-methylated glioblastoma were treated with chemoradiotherapy or chemoradiotherapy with cilengitide, an integrin inhibitor. We assessed the rate of treatment-associated changes in these groups according to the modified response assessment in neuro-oncology (RANO) criteria of 2017.

Methods

CENTRIC patients from both study arms with ≥3 follow-up MRIs were included. Preliminary PD (PPD) was defined as a ≥25% increase of the sum of perpendicular diameter (SPD) of a new or increasing lesion compared to baseline or nadir on the T1-MRI with gadolinium. Subsequent PD was defined as a second ≥25% increase of the SPD, at least 4 weeks later, or as a new lesion outside the radiation field. Treatment-associated changes were defined as stabilisation on ≥2 follow-up MRIs after PPD, each one 4 weeks later, or partial/complete regression on ≥1 follow-up MRI 4 weeks later.

Results

In total, 4,051 MRIs from 584 patients were available. This interim analysis included data on 462 patients with similar proportions in the cilengitide and control arm (50.9% and 49.1%). Due to missing MRIs or values, 128 were excluded. Of the remaining 334 patients, 157 (47%) patients showed RANO measurable disease at baseline or nadir (median SPD, 0mm2; interquartile range (IQR) 552.1 (0-552.1). After chemoradiotherapy with or without cilengitide, PPD occurred in 214 patients (64.1%) after a median time of 6.08 months after finishing radiation (IQR 11.4 (2.4-13.8), and 3.65 months after baseline or nadir (IQR 6.4 (2.1-8.5). After follow-up of these 214 patients, treatment-associated changes were diagnosed in 62 (18.6%) and PD was diagnosed in 48 (14.4%). The remaining 104 (31.1%) patients had no further follow-up MRI after PPD, mostly because a clinical decision to call PD was made. In the cilengitide group of 178 patients, 37 (20.8%) patients developed treatment-associated changes, and 23 (12.9%) patients developed PD, whereas in the control group of 156 patients, 25 (16%) patients developed treatment-associated changes, and 25 (16%) patients PD.

Conclusion

With the modified RANO criteria, the rate of treatment-associated changes was low compared to previous studies in newly diagnosed MGMT promoter-methylated glioblastoma. This rate did not change with addition of cilengitide. RANO-recommended radiological follow-up was not always awaited, which reflects clinical practice. Full data will be presented.

Long-lasting effects of chronic exposure to chemical pollution on the hologenome of the Manila clam

Chronic exposure to pollutants affects natural populations, creating specific molecular and biochemical signatures. In the present study, we tested the hypothesis that chronic exposure to pollutants might have substantial effects on the Manila clam hologenome long after removal from contaminated sites. To reach this goal, a highly integrative approach was implemented, combining transcriptome, genetic and microbiota analyses with the evaluation of biochemical and histological profiles of the edible Manila clam Ruditapes philippinarum, as it was transplanted for 6 months from the polluted area of Porto Marghera (PM) to the clean area of Chioggia (Venice lagoon, Italy). One month post-transplantation, PM clams showed several modifications to its resident microbiota, including an overrepresentation of the opportunistic pathogen Arcobacter spp. This may be related to the upregulation of several immune genes in the PM clams, potentially representing a host response to the increased abundance of deleterious bacteria. Six months after transplantation, PM clams demonstrated a lower ability to respond to environmental/physiological stressors related to the summer season, and the hepatopancreas-associated microbiota still showed different compositions among PM and CH clams. This study confirms that different stressors have predictable effects in clams at different biological levels and demonstrates that chronic exposure to pollutants leads to long-lasting effects on the animal hologenome. In addition, no genetic differentiation between samples from the two areas was detected, confirming that PM and CH clams belong to a single population. Overall, the obtained responses were largely reversible and potentially related to phenotypic plasticity rather than genetic adaptation. The results here presented will be functional for the assessment of the environmental risk imposed by chemicals on an economically important bivalve species.

P14.40 Trends in distribution of glioblastoma care and patient’s travel distance; results from the Dutch Brain Tumor Registry

BACKGROUND

Over the past years, increasing worldwide attention towards centralization of complex cancer care has been pursued as higher volume centers have shown improved outcomes. Changes in distribution of care and the impact on travel distance in glioblastoma patients have not been determined yet. In this study, we determine trends in distribution of glioblastoma care in the Netherlands over the last three decades and assess whether the observed trends affected travel distance for individual patients.

MATERIAL AND METHODS

Data were obtained from the Dutch Brain Tumor Registry from 1989 to 2018. All glioblastoma patients (≥18 years) were included for analysis. Patients, neurosurgical centers and radiotherapy centers were geocoded. Data were analyzed in six time intervals of 5 years. High volume hospitals were defined as &gt;50 cases per year. Travel distance was examined in two categories, ≤60km and &gt;60km respectively. Trend analyses for proportions were used to analyze hospital volume changes and travel distances.

RESULTS

A total of 16.477 glioblastoma patients were registered, with an annual increase from 203 patients in 1989 to 917 patients in 2018. Neurosurgical centers increased from 16 to 17 and for radiotherapy from 19 to 22 centers between 1989–1993 and 2014–2018. Mean neurosurgical- and radiotherapy center volumes increased from 12 to 39 (P=0.025) and 7 to 27 (P=0.025) patients per hospital per year from 1989–1993 to 2014–2018. High volume neurosurgical centers were observed since 2004, and an increased number of patients were treated in these centers, 27.8%, 52.6% and 64.1% in the time periods 2004–2008, 2009–2013, and 2014–2018 (P&lt;0.001). High volume radiology centers were observed since 2009, and 15.0% and 27.3% of patients were treated in these centers in the time periods 2009–2013 and 2014–2018 (P&lt;0.001). Patients with a travel distance &gt;60km to the neurosurgical center reduced from 15.8% to 13.2% (P=0.033). Travel distance &gt;60km to the radiotherapy center did not reduce significantly (10.4% to 8.8%, P=0.601).

CONCLUSION

An increasing number of glioblastoma patients were differentially treated in high volume neurosurgery and radiotherapy centers. The observation that this did not translate into increased travel distances, indicates accessible specialized Neuro-Oncology care for glioblastoma patients in The Netherlands.

P14.31 Between hospital variation in timings to multidisciplinary glioblastoma care in the Dutch Brain Tumor Registry

BACKGROUND

Delay in cancer care may adversely affect emotional distress, treatment outcome and survival. Optimal timings in multidisciplinary glioblastoma care are a matter of debate and clear national guidelines only exist for time to neurosurgery. We evaluated the between-hospital variation in timings to neurosurgery and adjuvant radiotherapy and chemotherapy in newly diagnosed glioblastoma patients in the Netherlands.

MATERIAL AND METHODS

Data were obtained from the nation-wide Dutch Brain Tumor Registry between 2014 and 2018. All adult patients with glioblastoma were included, covering all 18 neurosurgical hospitals, 28 radiotherapy hospitals, and 33 oncology hospitals. Long time-to-surgery (TTS) was defined as &gt;3 weeks from the date of first brain tumor diagnosis to surgery, long time-to-radiotherapy (TTR) as either &gt;4 or &gt;6 weeks after surgery, and long time-to-chemotherapy (TTC) as either &gt;4 or &gt;6 weeks after completion of radiotherapy. Between-hospital variation in standardized rate of long timings was analyzed in funnel plots after case-mix correction.

RESULTS

A total of 4203 patients were included. Median TTS was 20 days and 52.4% of patients underwent surgery within 3 weeks. Median TTR was 20 days and 24.6% of patients started radiotherapy within 4 weeks and 84.2% within 6 weeks after surgery. Median TTC was 28 days and 62.6% of patients received chemotherapy within 4 weeks and 91.8% within 6 weeks after radiotherapy. After case-mix correction, three (16.7%) neurosurgical hospitals had significantly more patients with longer than expected TTS. Three (10.7%) and one (3.6%) radiotherapy hospitals had significantly more patients with longer than expected TTR for &gt;4 and &gt;6 weeks, respectively. In seven (21.2%) chemotherapy hospitals, significantly less patients with TTC &gt;4 weeks were observed than expected. In four (12.1%) chemotherapy hospitals, significantly more patients with TTC &gt;4 weeks were observed than expected.

CONCLUSION

Between-hospital variation in timings to multidisciplinary treatment was observed in glioblastoma care in the Netherlands. A substantial percentage of patients experienced timings longer than anticipated.

P09.03 Fully integrating functional Ultrasound (fUS) into the onco-neurosurgical operating room: Towards a new real-time, high-resolution image-guided resection tool with multimodal potential

BACKGROUND

Onco-neurosurgical practice still relies heavily on pre-operatively acquired images to guide intra-operative decision-making for safe tumor removal, a practice with inherent pitfalls such as registration inaccuracy due to brain shift, and lack of real-time (functional) feedback. Exploiting the opportunity for real-time imaging of the exposed brain can improve intra-operative decision-making, neurosurgical safety and patient outcomes. Previously, we described functional Ultrasound (fUS) as a high-resolution, depth-resolved imaging technique able to detect functional regions and vascular morphology during awake resections. Here, we present for the first time fUS as a fully integrated, MRI/CT-registered imaging modality in the OR.

MATERIAL AND METHODS

fUS relies on high-frame-rate (HFR) ultrasound, making the technique sensitive for very small motions caused by vascular dynamics (µDoppler) and allowing measurements of changes in cerebral blood volume (CBV) with micrometer-millisecond precision. This opens up the possibility to 1) detect functional response, as CBV-changes reflect changes in metabolism of activated neurons through neurovascular coupling and 2) visualize in-vivo vascular morphology of tumor and healthy tissue. During a range of anesthetized and awake onco-neurosurgical procedures we acquired images of brain and spinal cord using conventional linear ultrasound probes connected to an experimental acquisition unit. Building on Brainlab’s ‘Cranial Navigation’ and ‘Intra-Operative Ultrasound’ modules, we could co-register our intra-operative Power Doppler Images (PDIs) to patient-registered MRI/CT-data. Using the ‘IGTLink’ research interface, we could access and store real-time tracking data for informed volume reconstructions in post-processing.

RESULTS

Intra-operative fUS could be registered to MRI/CT-images in real-time, showing overlays of PDIs at imaging depths of &gt;5 centimeters. During meningioma resections, these co-registered PDIs revealed fUS’ ability to visualize the tumor’s feeding vessels and surrounding healthy vasculature prior to durotomy, with a level of detail unprecedented by conventional MRI-sequences. Comparing post-operatively reconstructed 3D-vascular maps of pre- and post-durotomy acquisitions, further confirmed the dural dependency of the vascular network feeding the tumor. During awake resections, fUS revealed distinct functional areas as activated during motor and language tasks.

CONCLUSION

fUS is a new real-time, high-resolution and depth-resolved imaging technique, combining characteristics uniquely beneficial for a potential image-guided resection tool. The successful integration of fUS in the onco-neurosurgical OR demonstrated by our team, is an essential step towards clinical integration of fUS, as well as the technique’s validation against modalities such as MRI and CT.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium

BACKGROUND

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies.

PATIENTS AND METHODS

Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients).

RESULTS

A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality.

CONCLUSIONS

Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies.

CLINICAL TRIAL IDENTIFIER

NCT04354701.

Depuration processes affect the Vibrio community in the microbiota of the Manila clam, Ruditapes philippinarum

As filter-feeders, bivalve molluscs accumulate Vibrio into edible tissues. Consequently, an accurate assessment of depuration procedures and the characterization of the persistent Vibrio community in depurated shellfish represent a key issue to guarantee food safety in shellfish products. The present study investigated changes in the natural Vibrio community composition of the Ruditapes philippinarum microbiota with specific focus on human pathogenic species. For this purpose, the study proposed a MLSA-NGS approach (rRNA 16S, recA and pyrH) for the detection and identification of Vibrio species. Clam microbiota were analysed before and after depuration procedures performed in four depuration plants, using culture-dependent and independent approaches. Microbiological counts and NGS data revealed differences in terms of both contamination load and Vibrio community between depuration plants. The novel MLSA-NGS approach allowed for a clear definition of the Vibrio species specific to each depuration plant. Specifically, depurated clam microbiota showed presence of human pathogenic species. Ozone treatments and the density of clams in the depuration tank probably influenced the level of contamination and the Vibrio community composition. The composition of Vibrio community specific to each plant should be carefully evaluated during the risk assessment to guarantee a food-safe shellfish-product for the consumer.

A nation-wide transition in patient safety culture: a multilevel analysis on two cross-sectional surveys

QUALITY PROBLEM OR ISSUE

Patient safety is an important topic within healthcare systems. A favourable safety culture might promote safety. We examined whether a nation-wide patient safety programme (PSP) improved patient safety culture.

INITIAL ASSESSMENT

We initially measured patient safety culture among 3779 healthcare providers in 45 hospitals in the Netherlands, using the Hospital Survey on Patient Safety Culture.

CHOICE OF SOLUTION

A PSP based on two pillars: the implementation of a safety management system and the focus on 10 themes in which harm to patients appeared highly preventable. Elements of the safety management system were safety management, safety culture, risk assessments and continuous safety improvements.

IMPLEMENTATION

Implementation was nation-wide.

EVALUATION

After implementation of the programme, we assessed patient safety culture among 6605 healthcare providers in 24 Dutch hospitals and compared the scores with the initial measurement. We hypothesized that after the programme (1) scores on safety culture dimensions improved, (2) safety culture became more homogeneous within and between hospitals and (3) relative influence of hospitals on safety culture increased. A three-level mixed model for continuous responses was fit for 11 safety culture dimensions. We calculated average individual means, between-department variances, between-hospital variances and total variances per dimension.

LESSONS LEARNED

In general, a more favourable safety culture was seen after the PSP. However, hospitals and departments did not become more homogeneous, except for 'frequency of event reporting'. The variety in responses amongst departments and hospitals increased for several dimensions, implying that not all of them improved.

A proteomic study of resistance to Brown Ring disease in the Manila clam, Ruditapes philippinarum

Marine mollusk aquaculture has more than doubled over the past twenty years, accounting for over 15% of total aquaculture production in 2016. Infectious disease is one of the main limiting factors to the development of mollusk aquaculture, and the difficulties inherent to combating pathogens through antibiotic therapies or disinfection have led to extensive research on host defense mechanisms and host-pathogen relationships. It has become increasingly clear that characterizing the functional profiles of response to a disease is an essential step in understanding resistance mechanisms and moving towards more effective disease control. The Manila clam, Ruditapes philippinarum, is a main cultured bivalve species of economic importance which is affected by Brown Ring disease (BRD), an infection induced by the bacterium Vibrio tapetis. In this study, juvenile Manila clams were subjected to a 28-day controlled challenge with Vibrio tapetis, and visual and molecular diagnoses were carried out to distinguish two extreme phenotypes within the experimental clams: uninfected ("RES", resistant) and infected ("DIS", diseased) post-challenge. Total protein extractions were carried out for resistant and diseased clams, and proteins were identified using LC-MS/MS. Protein sequences were matched against a reference transcriptome of the Manila clam, and protein intensities based on label-free quantification were compared to reveal 49 significantly accumulated proteins in resistant and diseased clams. Proteins with known roles in pathogen recognition, lysosome trafficking, and various aspects of the energy metabolism were more abundant in diseased clams, whereas those with roles in redox homeostasis and protein recycling were more abundant in resistant clams. Overall, the comparison of the proteomic profiles of resistant and diseased clams after a month-long controlled challenge to induce the onset of Brown Ring disease suggests that redox homeostasis and maintenance of protein structure by chaperone proteins may play important and interrelated roles in resistance to infection by Vibrio tapetis in the Manila clam.

Clinical practice of language fMRI in epilepsy centers: a European survey and conclusions by the ESNR Epilepsy Working Group

Purpose

To assess current clinical practices throughout Europe with respect to acquisition, implementation, evaluation, and interpretation of language functional MRI (fMRI) in epilepsy patients.

Methods

An online survey was emailed to all European Society of Neuroradiology members (n = 1662), known associates (n = 6400), and 64 members of European Epilepsy network. The questionnaire featured 40 individual items on demographic data, clinical practice and indications, fMRI paradigms, radiological workflow, data post-processing protocol, and reporting.

Results

A total of 49 non-duplicate entries from European centers were received from 20 countries. Of these, 73.5% were board-certified neuroradiologists and 69.4% had an in-house epilepsy surgery program. Seventy-one percent of centers performed fewer than five scans per month for epilepsy. The most frequently used paradigms were phonemic verbal fluency (47.7%) and auditory comprehension (55.6%), but variants of 13 paradigms were described. Most centers assessed the fMRI task performance (75.5%), ensured cognitive-task adjustment (77.6%), trained the patient before scanning (85.7%), and assessed handedness (77.6%), but only 28.6% had special paradigms for patients with cognitive impairments. fMRI was post-processed mainly by neuroradiologists (42.1%), using open-source software (55.0%). Reporting was done primarily by neuroradiologists (74.2%). Interpretation was done mainly by visual inspection (65.3%). Most specialists (81.6%) were able to determine the hemisphere dominance for language in more than 75% of exams, attributing failure to the patient not performing the task correctly.

Conclusion

This survey shows that language fMRI is firmly embedded in the preoperative management of epilepsy patients. The wide variety of paradigms and the use of non-CE-marked software underline the need for establishing reference standards.

Electronic supplementary material

The online version of this article (10.1007/s00234-020-02397-w) contains supplementary material, which is available to authorized users.

The effects of glyphosate and AMPA on the mediterranean mussel Mytilus galloprovincialis and its microbiota

Glyphosate, the most widely used herbicide worldwide, targets the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme in the shikimate pathway found in plants and some microorganisms. While the potential for glyphosate to induce a broad range of biological effects in exposed organisms has been demonstrated, the global molecular mechanisms of toxicity and potential effects in bacterial symbionts remain unclear, in particular for ecologically important marine species such as bivalve molluscs. Here, the effects of glyphosate (GLY), its degradation product aminomethylphosphonic acid (AMPA), and a mixture of both (MIX) on the mussel M. galloprovincialis were assessed in a controlled experiment. For the first time, next generation sequencing (RNA-seq and 16S rRNA amplicon sequencing) was used to evaluate such effects at the molecular level in both the host and its respective microbiota. The results suggest that the variable capacity of bacterial species to proliferate in the presence of these compounds and the impairment of host physiological homeostasis due to AMPA and GLY toxicity may cause significant perturbations to the digestive gland microbiota, as well as elicit the spread of potential opportunistic pathogens such as Vibrio spp.. The consequent host-immune system activation identified at the molecular and cellular level could be aimed at controlling changes occurring in the composition of symbiotic microbial communities. Overall, our data raise further concerns about the potential adverse effects of glyphosate and AMPA in marine species, suggesting that both the effects of direct toxicity and the ensuing changes occurring in the host-microbial community must be taken into consideration to determine the overall ecotoxicological hazard of these compounds.

Potential for Genetic Improvement of Resistance to Perkinsus olseni in the Manila Clam, Ruditapes philippinarum, Using DNA Parentage Assignment and Mass Spawning

The Manila clam Ruditapes philippinarum, a major cultured shellfish species, is threatened by infection with the microparasite Perkinsus olseni, whose prevalence increases with high water temperatures. Under the current trend of climate change, the already severe effects of this parasitic infection might rapidly increase the frequency of mass mortality events. Treating infectious diseases in bivalves is notoriously problematic, therefore selective breeding for resistance represents a key strategy for mitigating the negative impact of pathogens. A crucial step in initiating selective breeding is the estimation of genetic parameters for traits of interest, which relies on the ability to record parentage and accurate phenotypes in a large number of individuals. Here, to estimate the heritability of resistance against P. olseni, a field experiment mirroring conditions in industrial clam production was set up, a genomic tool was developed for parentage assignment, and parasite load was determined through quantitative PCR. A mixed-family cohort of potentially 1,479 clam families was produced in a hatchery by mass spawning of 53 dams and 57 sires. The progenies were seeded in a commercial clam production area in the Venice lagoon, Italy, where high prevalence of P. olseni had previously been reported. Growth and parasite load were monitored every month and, after 1 year, more than 1,000 individuals were collected for DNA samples and phenotype recording. A pooled sequencing approach was carried out using DNA samples from the hatchery broodstock and from a Venice lagoon clam population, providing candidate markers used to develop a 245-SNP panel. Parentage assignment for 246 F1 individuals showed sire and dam representation were high (75 and 85%, respectively), indicating a very limited risk of inbreeding. Moderate heritability (0.23 ± 0.11-0.35 ± 0.13) was estimated for growth traits (shell length, shell weight, total weight), while parasite load showed high heritability, estimated at 0.51 ± 0.20. No significant genetic correlations were found between growth-associated traits and parasite load. Overall, the preliminary results provided by this study show high potential for selecting clams resistant to parasite load. Breeding for resistance may help limit the negative effects of climate change on clam production, as the prevalence of the parasite is predicted to increase under a future scenario of higher temperatures. Finally, the limited genetic correlation between resistance and growth suggests that breeding programs could incorporate dual selection without negative interactions.

Host-microbiota interactions shed light on mortality events in the striped venus clam Chamelea gallina

Mass mortalities due to disease outbreaks have recently affected a number of major taxa in marine ecosystems. Climate- and pollution-induced stress may compromise host immune defenses, increasing the risk of opportunistic diseases. Despite growing evidence that mass mortality events affecting marine species worldwide are strongly influenced by the interplay of numerous environmental factors, the reductionist approaches most frequently used to investigate these factors hindered the interpretation of these multifactorial pathologies. In this study, we propose a broader approach based on the combination of RNA-sequencing and 16S microbiota analyses to decipher the factors underlying mass mortality in the striped venus clam, Chamelea gallina, along the Adriatic coast. On one hand, gene expression profiling and functional analyses of microbial communities showed the over-expression of several genes and molecular pathways involved in xenobiotic metabolism, suggesting potential chemical contamination in mortality sites. On the other hand, the down-regulation of several genes involved in immune and stress response, and the over-representation of opportunistic pathogens such as Vibrio and Photobacterium spp. indicates that these microbial species may take advantage of compromised host immune pathways and defense mechanisms that are potentially affected by chemical exposure, resulting in periodic mortality events. We propose the application of our approach to interpret and anticipate the risks inherent in the combined effects of pollutants and microbes on marine animals in today's rapidly changing environment.

OS10.1 Survival analysis of IDH wildtype astrocytomas with molecular features of glioblastoma, WHO grade IV

BACKGROUND

Recently, isocitrate dehydrogenase wildtype (IDHwt) lower grade gliomas (LGGs) that have a telomerase reverse transcriptase (TERT) promoter mutation and/or gain of chromosome 7 combined with loss of chromosome 10 and/or epidermal growth factor receptor amplification have been reclassified as IDHwt astrocytomas with molecular features of glioblastoma, WHO grade IV (‘astrocytomas IDHwt, WHO IV’). Survival of these tumors meeting the criteria of these tumors is less well studied. The objective of this study is to compare the overall survival (OS) between the IDHwt astrocytomas, WHO IV and histological glioblastomas (GBMs).

MATERIAL AND METHODS

In this retrospective multicenter cohort study, all adult patients with a newly diagnosed IDHwt LGG (histologically WHO grade II or III) and with molecular data available were selected from the Erasmus MC and the LUMC from October 2002 to April 2019. LGG patients showing contrast enhancement with necrosis on the MRI at the time of histological diagnosis were excluded. Molecular data were determined using a diagnostic NGS panel. A historical cohort of 195 patients with IDHwt GBMs with molecular data available was used to compare OS. OS was measured from the date of the first diagnostic MR scan.

RESULTS

79 IDHwt LGG patients were identified of which 62 patients had molecular features of glioblastoma (‘astrocytomas IDHwt, WHO IV’), 11 patients did not have these molecular features (‘astrocytomas IDHwt, WHO II & III’). In the remaining 6 patients the molecular data were not conclusive (astrocytomas IDHwt, WHO NOS). Patients with astrocytomas IDHwt, WHO IV were slightly older at diagnosis (median age = 57 years) than patients with GBMs IDHwt in the reference cohort or astrocytomas IDHwt, WHO II & III (respectively: median age 55 years, p=0.032 and 47 years, p=0.035). The relatively young age of our GBM IDHwt cohort reflects more extensive molecular testing in younger patients and histologically lower grade tumors. The median OS of astrocytomas IDHwt, WHO IV (23.8 months) was similar to the median OS of GBMs (19.2 months, log-rank test p=0.37). The median OS in 19 patients with only TERT promoter mutations was 16.8 months, similar to GBMs (p=0.94).

CONCLUSION

There is no statistically significant difference between the OS of IDHwt astrocytomas with molecular features of glioblastoma and the OS of true glioblastomas. Grade II and III IDHwt astrocytoma with molecular features of glioblastoma should be designated WHO grade IV. The presence of TERT promoter mutations alone in this histological context also qualifies for this designation.

OS9.4 The added value of radiomics to a clinical prognostic model in patients with low-grade glioma

BACKGROUND

In recent years, radiomics has become of increasing interest in studies of patients with low-grade glioma (LGG). Imaging features extracted from Magnetic Resonance Imaging (MRI) have shown to have the potential to predict genotype and overall survival in patients with LGG. However, until now, the potential of radiomics to add prognostic value to clinical prognostic models has hardly been investigated.The purpose of this study is to investigate the added prognostic value of quantitative magnetic resonance imaging features to a clinical prognostic model for patients with LGG.

MATERIAL AND METHODS

This retrospective cohort study included adult patients with newly diagnosed LGG who underwent tumor resection or biopsy between October 2002 and March 2017 at the Erasmus MC, University Medical Center Rotterdam (EMC). A set of 77 imaging features were extracted from preoperative T1w and T2w magnetic resonance sequences. These included first order histogram, texture, shape and location features of the volume of interest. The primary outcome of our study was overall survival (OS) and the secondary outcomewas progression-free survival (PFS).

RESULTS

A total of 259 patients were included. The median follow-up was 5.3 years (interquartile range, 3.4–8.2). The median OS was 9.08 years (95% CI: 6.70–11.5). Four imaging features increased the fit of our clinical prognostic model for OS significantly: T1 local binary pattern peak (hazard ratio (HR) 1.028, p=0.041), T2 histogram energy (HR 1.000, p<0.001), T2 histogram peak (HR 1.000, p=0.002) and standard deviation of radial distance (SDRD) (HR 1.412, p<0.001). The median PFS was 4.14 years (95% CI: 3.49–4.79). Only one imaging feature increased the fit of our clinical prognostic model for PFS significantly: standard deviation of radial distance (HR 1.278, p=0.006).

CONCLUSION

This study demonstrates that several radiomics features have the potential to help predict OS and PFS in patients with LGG more accurately than models constituted only by clinical features. In our study, four quantitative MRI features were found to be of added prognostic value. However, future studies should validate our results.

68Ga-PSMA-PET/CT and Diffusion MRI Targeting for Cone-Beam CT-Guided Bone Biopsies of Castration-Resistant Prostate Cancer Patients

Introduction

Precision medicine expands the treatment options for metastatic castration-resistant prostate cancer (mCRPC) by targeting druggable genetic aberrations. Aberrations can be identified following molecular analysis of metastatic tissue. Bone metastases, commonly present in mCRPC, hinder precision medicine due to a high proportion of biopsies with insufficient tumor cells for next-generation DNA sequencing. We aimed to investigate the feasibility of incorporating advanced target planning and needle guidance in bone biopsies and whether this procedure increases biopsy tumor yield and success rate of molecular analysis as compared to the current standards, utilizing only CT guidance.

Materials and Methods

In a pilot study, ten mCRPC patients received ⁶⁸Ga-prostate-specific membrane antigen (PSMA)-PET/CT and diffusion-weighted MRI as biopsy planning images. These datasets were fused for targeting metastatic lesions with high tumor densities. Biopsies were performed under cone-beam CT (CBCT) guidance. Feasibility of target planning and needle guidance was assessed, and success of molecular analysis and tumor yield were reported.

Results

Fusion target planning and CBCT needle guidance were feasible. Nine out of ten biopsies contained prostate cancer cells, with a median of 39% and 40% tumor cells by two different sequencing techniques. Molecular analysis was successful in eight of ten patients (80%). This exceeds previous reports on CT-guided biopsies that ranged from 33 to 44%. In two patients, important druggable aberrations were found.

Discussion

A biopsy procedure using advanced target planning and needle guidance is feasible and can increase the success rate of molecular analysis in bone metastases, thereby having the potential of improving treatment outcome for patients with mCRPC.

Level of Evidence

Level 4, case series.

Dementia imaging in clinical practice: a European-wide survey of 193 centres and conclusions by the ESNR working group

PURPOSE

Through a European-wide survey, we assessed the current clinical practice of imaging in the primary evaluation of dementia, with respect to standardised imaging, evaluation and reporting.

METHODS

An online questionnaire was emailed to all European Society of Neuroradiology (ESNR) members (n = 1662) and non-members who had expressed their interest in ESNR activities in the past (n = 6400). The questionnaire featured 42 individual items, divided into multiple choice, single best choice and free text answers. Information was gathered on the context of the practices, available and preferred imaging modalities, applied imaging protocols and standards for interpretation, reporting and communication.

RESULTS

A total of 193 unique (non-duplicate) entries from the European academic and non-academic institutions were received from a total of 28 countries. Of these, 75% were neuroradiologists, 12% general radiologists and 11% (neuro) radiologists in training. Of responding centres, 38% performed more than five scans/week for suspected dementia. MRI was primarily used in 72% of centres. Over 90% of centres acquired a combination of T2w, FLAIR, T1w, DWI and T2*w sequences. Visual rating scales were used in 75% of centres, most often the Fazekas and medial temporal atrophy scale; 32% of respondents lacked full confidence in their use. Only 23% of centres performed volumetric analysis. A minority of centres (28%) used structured reports.

CONCLUSIONS

Current practice in dementia imaging is fairly homogeneous across Europe, in terms of image acquisition and image interpretation. Hurdles identified include training on the use of visual rating scales, implementation of volumetric assessment and structured reporting.

Exploring new landmarks: analysis of Twitter usage during the 41st ESNR Annual Meeting

We analyzed the use of Twitter during the 41st Annual Meeting of the European Society of Neuroradiology (ESNR) held in Rotterdam from 19 to 23 September 2018. The aim was to check the status of the European neuroradiology Twitter community and to discover which topics were discussed most often. The data were compared with a similar analysis performed during the Annual Meeting of the American Society of Neuroradiology (ASNR) in 2014. Even though the analysis demonstrated a low use of Twitter during the ESNR meeting, the platform still generated an important volume of impressions and engagement. This use was noted by the global community because topics of the meeting, such as the value of radiological reporting and advanced imaging, were discussed worldwide. These data, also compared to the American meeting, suggests a need for more prolific use and engagement with ESNR social media accounts in order to draw our members into discussions during meetings and to reinforce the place of European neuroradiology in the debate on key imaging topics as well as promoting society events.

Exploring quantitative group-wise differentiation of Alzheimer's disease and behavioural variant frontotemporal dementia using tract-specific microstructural white matter and functional connectivity measures at multiple time points

Objectives

This study explored group-wise quantitative measures of tract-specific white matter (WM) microstructure and functional default mode network (DMN) connectivity to establish an initial indication of their clinical applicability for early-stage and follow-up differential diagnosis of Alzheimer’s disease (AD) and behavioural variant frontotemporal dementia (bvFTD).

Methods

Eleven AD and 12 bvFTD early-stage patients and 18 controls underwent diffusion tensor imaging and resting state functional magnetic resonance imaging at 3 T. All AD and 6 bvFTD patients underwent the same protocol at 1-year follow-up. Functional connectivity measures of DMN and WM tract-specific diffusivity measures were determined for all groups. Exploratory analyses were performed to compare all measures between the three groups at baseline and between patients at follow-up. Additionally, the difference between baseline and follow-up diffusivity measures in AD and bvFTD patients was compared.

Results

Functional connectivity of the DMN was not different between groups at baseline and at follow-up. Diffusion abnormalities were observed widely in bvFTD and regionally in the hippocampal cingulum in AD. The extent of the differences between bvFTD and AD was diminished at follow-up, yet abnormalities were still more pronounced in bvFTD. The rate of change was similar in bvFTD and AD.

Conclusions

This study provides a tentative indication that quantitative tract-specific microstructural WM abnormalities, but not quantitative functional connectivity of the DMN, may aid early-stage and follow-up differential diagnosis of bvFTD and AD. Specifically, pronounced microstructural changes in anterior WM tracts may characterise bvFTD, whereas microstructural abnormalities of the hippocampal cingulum may characterise AD.

Key Points

• The clinical applicability of quantitative brain imaging measures for early-stage and follow-up differential diagnosis of dementia subtypes was explored using a group-wise approach.

• Quantitative tract-specific microstructural white matter abnormalities, but not quantitative functional connectivity of the default mode network, may aid early-stage and follow-up differential diagnosis of behavioural variant frontotemporal dementia and Alzheimer’s disease.

• Pronounced microstructural white matter (WM) changes in anterior WM tracts characterise behavioural variant frontotemporal dementia, whereas microstructural WM abnormalities of the hippocampal cingulum in the absence of other WM changes characterise Alzheimer’s disease.

Electronic supplementary material

The online version of this article (10.1007/s00330-019-06061-7) contains supplementary material, which is available to authorized users.

Inter-rater agreement in glioma segmentations on longitudinal MRI

Background

Tumor segmentation of glioma on MRI is a technique to monitor, quantify and report disease progression. Manual MRI segmentation is the gold standard but very labor intensive. At present the quality of this gold standard is not known for different stages of the disease, and prior work has mainly focused on treatment-naive glioblastoma. In this paper we studied the inter-rater agreement of manual MRI segmentation of glioblastoma and WHO grade II-III glioma for novices and experts at three stages of disease. We also studied the impact of inter-observer variation on extent of resection and growth rate.

Methods

In 20 patients with WHO grade IV glioblastoma and 20 patients with WHO grade II-III glioma (defined as non-glioblastoma) both the enhancing and non-enhancing tumor elements were segmented on MRI, using specialized software, by four novices and four experts before surgery, after surgery and at time of tumor progression. We used the generalized conformity index (GCI) and the intra-class correlation coefficient (ICC) of tumor volume as main outcome measures for inter-rater agreement.

Results

For glioblastoma, segmentations by experts and novices were comparable. The inter-rater agreement of enhancing tumor elements was excellent before surgery (GCI 0.79, ICC 0.99) poor after surgery (GCI 0.32, ICC 0.92), and good at progression (GCI 0.65, ICC 0.91). For non-glioblastoma, the inter-rater agreement was generally higher between experts than between novices. The inter-rater agreement was excellent between experts before surgery (GCI 0.77, ICC 0.92), was reasonable after surgery (GCI 0.48, ICC 0.84), and good at progression (GCI 0.60, ICC 0.80). The inter-rater agreement was good between novices before surgery (GCI 0.66, ICC 0.73), was poor after surgery (GCI 0.33, ICC 0.55), and poor at progression (GCI 0.36, ICC 0.73). Further analysis showed that the lower inter-rater agreement of segmentation on postoperative MRI could only partly be explained by the smaller volumes and fragmentation of residual tumor. The median interquartile range of extent of resection between raters was 8.3% and of growth rate was 0.22 mm/year.

Conclusion

Manual tumor segmentations on MRI have reasonable agreement for use in spatial and volumetric analysis. Agreement in spatial overlap is of concern with segmentation after surgery for glioblastoma and with segmentation of non-glioblastoma by non-experts.

•

Inter-rater agreement for longitudinal glioma segmentation was determined.

•

Agreement between 4 experts was higher than between 4 novices.

•

Three time-points of glioblastoma (WHO IV) and diffuse glioma (WHO II-III) are studied.

•

Impact on extent of resection and growth rate measurements was determined.

Ecotoxicological effects of the herbicide glyphosate in non-target aquatic species: Transcriptional responses in the mussel Mytilus galloprovincialis

Glyphosate has been the most widely used herbicide worldwide over the last three decades, raising increasing concerns for its potential impacts on environmental and human health. Recent studies revealed that glyphosate occurs in soil, surface water, and groundwater, and residues are found at all levels of the food chain, such as drinking water, plants, animals, and even in humans. While research has demonstrated that glyphosate can induce a broad range of biological effects in exposed organisms, the global molecular mechanisms of action still need to be elucidated, in particular for marine species. In this study, we characterized for the first time the molecular mechanisms of action of glyphosate in a marine bivalve species after exposure to environmentally realistic concentrations. To reach such a goal, Mediterranean mussels Mytilus galloprovincialis, an ecologically and economically relevant species, were exposed for 21 days to 10, 100, and 1000 μg/L and digestive gland transcriptional profiles were investigated through RNA-seq. Differential expression analysis identified a total of 111, 124, and 211 differentially regulated transcripts at glyphosate concentrations of 10, 100, and 1000 μg/L, respectively. Five genes were found consistently differentially expressed at all investigated concentrations, including SERP2, which plays a role in the protection of unfolded target proteins against degradation, the antiapoptotic protein GIMAP5, and MTMR14, which is involved in macroautophagy. Functional analysis of differentially expressed genes reveals the disruption of several key biological processes, such as energy metabolism and Ca2+ homeostasis, cell signalling, and endoplasmic reticulum stress response. Together, the results obtained suggest that the presence of glyphosate in the marine ecosystem should raise particular concern because of its significant effects even at the lowest concentration.

Glioma imaging in Europe: A survey of 220 centres and recommendations for best clinical practice

Objectives

At a European Society of Neuroradiology (ESNR) Annual Meeting 2015 workshop, commonalities in practice, current controversies and technical hurdles in glioma MRI were discussed. We aimed to formulate guidance on MRI of glioma and determine its feasibility, by seeking information on glioma imaging practices from the European Neuroradiology community.

Methods

Invitations to a structured survey were emailed to ESNR members (n=1,662) and associates (n=6,400), European national radiologists’ societies and distributed via social media.

Results

Responses were received from 220 institutions (59% academic). Conventional imaging protocols generally include T2w, T2-FLAIR, DWI, and pre- and post-contrast T1w. Perfusion MRI is used widely (85.5%), while spectroscopy seems reserved for specific indications. Reasons for omitting advanced imaging modalities include lack of facility/software, time constraints and no requests. Early postoperative MRI is routinely carried out by 74% within 24–72 h, but only 17% report a percent measure of resection. For follow-up, most sites (60%) issue qualitative reports, while 27% report an assessment according to the RANO criteria. A minority of sites use a reporting template (23%).

Conclusion

Clinical best practice recommendations for glioma imaging assessment are proposed and the current role of advanced MRI modalities in routine use is addressed.

Key Points

• We recommend the EORTC-NBTS protocol as the clinical standard glioma protocol.

• Perfusion MRI is recommended for diagnosis and follow-up of glioma.

• Use of advanced imaging could be promoted with increased education activities.

• Most response assessment is currently performed qualitatively.

• Reporting templates are not widely used, and could facilitate standardisation.

Electronic supplementary material

The online version of this article (10.1007/s00330-018-5314-5) contains supplementary material, which is available to authorized users.

[Self-referrals at Emergency Care Access Points and triage by General Practitioner Cooperatives]

OBJECTIVE

There is a trend for General Practitioner Cooperatives (GPCs) to co-locate with emergency departments (EDs) of hospitals at Emergency Care Access Points (ECAPs), where the GPCs generally conduct triage and treat a large part of self-referrals who would have gone to the ED by themselves in the past. We have examined patient and care characteristics of self-referrals at ECAPs where triage was conducted by GPCs, also to determine the percentage of self-referrals being referred to the ED.

DESIGN

Retrospective cross-sectional observational study.

METHOD

Descriptive analyses of routine registration data from self-referrals of five ECAPs (n = 20.451). Patient age, gender, arrival time, urgency, diagnosis and referral were analysed.

RESULTS

Of the self-referrals, 57.9% was male and the mean age was 32.7 years. The number of self-referrals per hour was highest during weekends, particularly between 11 a.m. and 5 p.m. On weekdays, there was a peak between 5 and 9 p.m. Self-referrals were mostly assigned a low-urgency grade (35.7% - U4 or U5) or a mid-urgency grade (49% - U3). Almost half of the self-referrals had trauma of the locomotor system (28%) or the skin (27.3%). In total, 23% of the patients was referred to the ED.

CONCLUSION

Self-referred patients at GPCs are typically young, male and have low- to mid-urgency trauma-related problems. Many self-referrals present themselves on weekend days or early weekday evenings. Over three quarters of these patients can be treated by the GPCs, without referral to the ED. This reduces the workload at the ED.

Functional connectivity and microstructural white matter changes in phenocopy frontotemporal dementia

Objectives

Phenocopy frontotemporal dementia (phFTD) is a rare and poorly understood clinical syndrome. PhFTD shows core behavioural variant FTD (bvFTD) symptoms without associated cognitive deficits and brain abnormalities on conventional MRI and without progression. In contrast to phFTD, functional connectivity and white matter (WM) microstructural abnormalities have been observed in bvFTD. We hypothesise that phFTD belongs to the same disease spectrum as bvFTD and investigated whether functional connectivity and microstructural WM changes similar to bvFTD are present in phFTD.

Methods

Seven phFTD patients without progression or alternative psychiatric diagnosis, 12 bvFTD patients and 17 controls underwent resting state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI). Default mode network (DMN) connectivity and WM measures were compared between groups.

Results

PhFTD showed subtly increased DMN connectivity and subtle microstructural changes in frontal WM tracts. BvFTD showed abnormalities in similar regions as phFTD, but had lower increased DMN connectivity and more extensive microstructural WM changes.

Conclusions

Our findings can be interpreted as neuropathological changes in phFTD and are in support of the hypothesis that phFTD and bvFTD may belong to the same disease spectrum. Advanced MRI techniques, objectively identifying brain abnormalities, would therefore be potentially suited to improve the diagnosis of phFTD.

Key points

• PhFTD shows brain abnormalities that are similar to bvFTD.

• PhFTD shows increased functional connectivity in the parietal default mode network.

• PhFTD shows microstructural white matter abnormalities in the frontal lobe.

• We hypothesise phFTD and bvFTD may belong to the same disease spectrum.

Electronic supplementary material

The online version of this article (doi:10.1007/s00330-016-4490-4) contains supplementary material, which is available to authorized users.

[Practice assistant sometimes misses urgent request for help: telephone triage in general practice]

OBJECTIVE

To assess the organisation and appropriateness of telephone triage in general practices in the Netherlands.

DESIGN

Cross-sectional observational study.

METHODS

Via e-mail we invited all members of the Dutch Association of practice assistants to complete an online survey. The questionnaire included questions about practice assistants' background characteristics and the practices' triage organisation. Furthermore, they were asked to assess the indicated type of care for a number of fictive case scenarios involving a variety of health problems and levels of urgency. To determine the appropriateness of the respondents' assessments, each was compared to a reference standard agreed by experts. In addition, the association between practice assistants' background characteristics and organizational setup of the triage organisation with the appropriateness of triage was examined.

RESULTS

The response rate was 41.1% (N=973). The required care was assessed appropriately in 63.6% of the cases, over-estimated in 19.3% and under-estimated in 17.1% of cases. The sensitivity of identifying patients with a highly urgent problem was 76.7%, whereas the specificity was 94.0%. The appropriateness of the assessments of the required care was higher for more experienced assistants and assistants with regular daily work meetings with the GP. Triage training, use of a triage tool and authorization of advice provision were not associated with appropriateness of triage.

CONCLUSION

Triage by practice assistants in general practices is efficient, but potentially unsafe in highly urgent cases. It is therefore important to train practice assistants in the identification of highly urgent cases.

[Normoglycaemic ketoacidosis in pregnant patients with diabetes; early recognition is critical]

Diabetic ketoacidosis (DKA) during pregnancy is a rare but very serious complication that requires early recognition and treatment to prevent severe complications. Here we present three cases in which DKA occurred during normoglycaemia, demonstrating the importance of early recognition. In pregnancy, DKA can occur at lower blood glucose levels than usual due to several pregnancy-related factors, such as altered metabolism, increased insulin resistance, lower buffering capacity related to chronic hyperventilation and hunger. Symptoms that are common during pregnancy, such as vomiting, may be missed as a first sign of DKA. In patients with type 1 diabetes mellitus (especially those on continuous subcutaneous insulin infusion) insulin administration must never be discontinued, as this prevents lipolysis and ketone formation. Physicians and patients need to be aware of the risks and management of DKA in pregnancy.

[A woman with a cavity in an intervertebral disc on the CT-scan]

The CT scan of a 77-year-old woman showed hypodense structures in the spine called vacuum phenomenon as an incidental finding. The cause in the majority of cases is the degeneration of tissue but vacuum phenomenon is also associated with other disorders. It is important to distinguish between benign causes and malignant causes. Unfamiliarity with this vacuum phenomenon may lead to suboptimal treatment.

Increased fat and polyunsaturated fatty acid content in sow gestation diet has no effect on gene expression in progeny during the first 7 days of life

The 'developmental origins of health and disease' hypothesis proposes not only that we are what we eat, but also that we could be what our parents ate. Here, we aimed to improve health and performance of young piglets via maternal diets based on the hypothesis that maternal nutritional interventions change metabolic programming in piglets, reflected by differential gene expression early in life. Therefore, sows were fed either a regular diet, based on barley, wheat and wheat by-products, sugar beet pulp, palm oil and oilseed meal, or a high-fat (HF) diet consisting of the regular diet supplemented with an additional amount of 3.5% soybean oil and 1% fish oil at the expense of palm oil and wheat. Performance results, physiological parameters and gene expression in liver of piglets and blood of piglets and sows at day 7 after farrowing from both diet groups were compared. The HF diet tended to enhance growth rate of the offspring in the first week of life. No significant differences in gene expression in liver tissue and blood could be detected between the two groups, neither with whole-genome microarray analysis, nor with gene specific qPCR analysis. In this study, the feeding of a high-fat diet with increased amounts of polyunsaturated fatty acid (PUFA) to gestating sows under practical farm settings did not induce significant changes in gene expression in sows and offspring.