Ultra-Fast List-Mode Reconstruction of Short PET Frames and Example Applications

Standard clinical reconstructions usually require several minutes to complete, and this time is mostly independent of the duration of the data being reconstructed. Applications such as data-driven motion estimation, which require many short frames over the duration of the scan, become unfeasible with such long reconstruction times. In this work, we present an infrastructure whereby ultra-fast list-mode reconstructions of very short frames (≤1 s) are performed. With this infrastructure, it is possible to have a dynamic series of frames that can be used for various applications, such as data-driven motion estimation, whole-body surveys, quick reconstructions of gated data to select the optimal gate for a given attenuation map, and, if the infrastructure runs simultaneously with the scan, real-time display of the reconstructed data during the scan and automated alerts for patient motion. Methods: A fast ray-tracing time-of-flight projector was implemented and parallelized. The reconstruction parameters were optimized to allow for fast performance: only a few iterations are performed, without point-spread-function modeling, and scatter correction is not used. The resulting reconstructions are thus not quantitative but are acceptable for motion estimation and visualization purposes. Data-driven motion can be estimated using image registration, with the resultant motion data being used in a fully motion-corrected list-mode reconstruction. Results: The infrastructure provided images that can be used for visualization and gating purposes and for motion estimation using image registration. Several case studies are presented, including data-driven motion estimation and correction for brain studies, abdominal studies in which respiratory and cardiac motion is visible, and a whole-body survey. Conclusion: The presented infrastructure provides the capability to quickly create a series of very short frames for PET data that can be used in a variety of applications.

Demographic, clinical and lifestyle-related correlates of accelerometer assessed physical activity and fitness in newly diagnosed patients with head and neck cancer

Introduction: Objective measurements of levels of physical activity and fitness in patients with head and neck cancer (HNC) are lacking. Furthermore, demographic, clinical and lifestyle-related correlates of low levels of physical activity and fitness in patients with HNC are unknown. This study aims to investigate the levels of accelerometer that assessed physical activity and fitness in patients with HNC and to identify their demographical, clinical and lifestyle-related correlates.Methods: Two hundred and fifty-four patients who were recently diagnosed with HNC and participated in the NETherlands QUality of life and Biomedical cohort studies In head and neck Cancer (NET-QUBIC) study were included. Physical activity (accelerometer), cardiorespiratory fitness (Chester Step Test), hand grip strength (hand dynamometer) and lower body muscle function (30-second chair-stand test) were assessed. Multivariable linear regression analyses with a stepwise forward selection procedure were used.Results: Patients spent 229 min/d in physical activity of which 18 min/d in moderate-to-vigorous physical activity. The mean predicted VO₂max was 27.9 ml/kg/min, the mean hand grip strength was 38.1 kg and the mean number of standings was 14.3. Patients with lower educational level, more comorbidity and higher tumor stage spent significantly less time in physical activity. Older patients, females and patients with a higher tumor stage had significantly lower cardiorespiratory fitness levels. Older patients, females, patients with more comorbidity, patients with normal weight and patients who have never smoked had significantly lower hand grip strength. Older patients, patients with lower educational level, smokers and patients with more comorbidity had a significantly lower function of lower body muscle.Conclusions: Pre-treatment levels of physical activity, cardiorespiratory fitness and lower body muscle function are low in patients with HNC. Based on this study, exercise programs targeted and tailored to patients with low levels of physical activity and fitness can be developed.

PET image reconstruction using physical and mathematical modelling for time of flight PET-MR scanners in the STIR library

This work demonstrates how computational and physical modelling of the positron emission tomography (PET) image acquisition process for a state-of-the-art integrated PET and magnetic resonance imaging (PET-MR) system can produce images comparable to the manufacturer. The GE SIGNA PET/MR scanner is manufactured by General Electric and has time-of-flight (TOF) capabilities of about 390 ps. All software development took place in the Software for Tomographic Image Reconstruction (STIR: http://stir.sf.net) library, which is a widely used open source software to reconstruct data as exported from emission tomography scanners. The new software developments will be integrated into STIR, providing the opportunity for researchers worldwide to establish and expand their image reconstruction methods. Furthermore, this work is of particular significance as it provides the first validation of TOF PET image reconstruction for real scanner datasets using the STIR library. This paper presents the methodology, analysis, and critical issues encountered in implementing an independent reconstruction software package. Acquired PET data were processed via several appropriate algorithms which are necessary to produce an accurate and precise quantitative image. This included mathematical, physical and anatomical modelling of the patient and simulation of various aspects of the acquisition. These included modelling of random coincidences using 'singles' rates per crystals, detector efficiencies and geometric effects. Attenuation effects were calculated by using the STIR's attenuation correction model. Modelling all these effects within the system matrix allowed the reconstruction of PET images which demonstrates the metabolic uptake of the administered radiopharmaceutical. These implementations were validated using measured phantom and clinical datasets. The developments are tested using the ordered subset expectation maximisation (OSEM) and the more recently proposed kernelised expectation maximisation (KEM) algorithm which incorporates anatomical information from MR images into PET reconstruction.

P2584Extracellular vesicles are relevant transporters of C16 ceramide and induce apoptosis in endothelial vesicle recipient cells

Introduction

Extracellular vesicles (EVs) have recently been identified as important intercellular transporters of biologically active molecules. Besides microRNAs, which have been shown to mediate an important part of the EV function, various sphingolipids have been shown to be exported into EVs. Among these sphingolipids, ceramides have been gained interest in the cardiovascular context, because elevated plasma levels of d18:1–16:0 Ceramide (C16) have been shown to correlate with an increased risk for cardiovascular events. How ceramides are enriched in endothelial cell derived-EVs and if they are transferred to EV recipient cells to exert specific biological functions is currently unknown.

Methods and results

Endothelial cell derived large EVs were isolated from human coronary artery endothelial cells (HCAECs) via differential centrifugation of the culture supernatant (1 x 1500 g / 15 min + 2 x 20,000 g / 40 min). EVs were characterized by immunoblotting, electron microscopy and nanoparticle tracking analysis (Size: 252±24 nm). Sphingolipids were extracted from HCAECs and EVs (with and without glycemic injury by 30mmol/L glucose for 72 h) by solid phase extraction and analysed via Q-TOF MS/MS mass spectrometry. Lipidomic analysis revealed an enrichment of all sphingolipid classes in EVs, including C16, which was most abundantly present in EVs. As a next step, we tested if ceramides can be transferred between HCAECs by EVs. Therefore, HCAECs were incubated with NBD-labeled ceramide. NBD-Ceramide uptake into HCAECs and vesicular transfer to native HCAECs were confirmed by fluorescence microscopic imaging. Importantly, the transfer of NBD-Ceramide was abrogated if the vesicles were degraded in Triton-X 1% before incubation with EV recipient cells, which confirms that the transfer is vesicle dependent. Additionally, uptake of C16 into HCAECs and release into EVs was confirmed via mass spectrometry. Viability of C16 treated HCAECs was significantly reduced at concentrations above 5 μM of C16 in an MTT-based assay. In order to assess if the increased vesicular packing and transfer of Ceramides also reduces viability of EV recipient cells, native HCAECs were incubated with EVs from HCAECs which were treated with 2 μM and 20 μM C16. Treatment with C16 enriched vesicles lead to a significant reduction of EV recipient cell viability in a dose dependant manner.

Conclusion

In the present study, we found that C16 is enriched in EVs and that C16 is transferred through EVs among HCAECs. Depending on the amount of transferred C16, this process reduces the viability of native EV recipient HCAECs. Furthermore, vesicular C16 export is increased after glycemic injury. In comparison to the amounts of free C16, which are necessary to induce a similar reduction in HCAEC viability, the amount of EV transferred C16 is negliable. Hence, vesicular packaging results in a high bioavailability of ceramides leading to a relevant regulation of endothelial cell death.

Acknowledgement/Funding

BONFOR Progamm University Bonn

2289Extracellular Vesicle-incorporated Long Noncoding RNA PUNISHER as a novel biomarker and effector of vascular function

Background

Circulating long noncoding RNAs (lncRNAs) have emerged as biomarkers and regulators in cardiovascular diseases. Whether small extracellular vesicles (sEV)-incorporated lncRNAs expression is regulated in coronary artery disease (CAD) is largely unknown. We aimed to explore the expression of plasma sEV-lncRNAs in patients with and without CAD as well as elucidate specific cellular function of sEV-incorporated lncRNA PUNISHER (also known as AGAP2-AS1) in vascular endothelial cells.

Methods and results

We quantified the expression level of 13 cardiac- or atherosclerosis-related lncRNAs by quantitative real-time PCR (qRT-PCR) in plasma sEV from 6 stable CAD, 6 ACS and 6 non-CAD (NCAD) patients. 4 lncRNAs showing stable expression (PUNISHER, GAS5, MALAT1, and H19) were further evaluated in the validation study including 65 stable CAD, 43 ACS and 42 NCAD patients. Among those, PUNISHER was significantly increased in patients with stable CAD and ACS compared to NCAD. Area under the curve (AUC) value was 0.7 for stable CAD and 0.8 for ACS respectively, suggesting plasma sEV-PUNISHER as a potential diagnostic biomarker for CAD. In vitro, atherosclerotic stimuli consisting of oxLDL or TNF-a treatment upregulated PUNISHER level in human coronary artery endothelial cell (HCAEC) and in corresponding sEV in a dose-dependent way. Mechanistically, RNA immunoprecipitation (RIP) assay identified hnRNPK as an interaction partner of PUNISHER regulating its packaging into sEV. In vitro, endothelial-derived sEV were internalized into recipient ECs and transported incorporated PUNISHER into recipient cells promoting an angiogenic response. Mechanical downstream analysis using PCR array showed that sEV-mediated PUNISHER transfer altered expression of vascular endothelial growth factor A (VEGFA) in recipient ECs.

Conclusion

This translational study highlights sEV-incorporated lncRNA PUNISHER as biomarker and effector in vascular disease.

P4145Endothelial NLRP3-Inflammasome impairs vascular function via microparticles

Background

In recent years inflammation has emerged to the centre of attention of cardiovascular research. One of its key figures is the NLRP3-inflammasome a multimeric protein complex that stimulates inflammatory responses in atherogenesis through proinflammatory cytokines like caspases IL-1β and -18. It is activated by danger signals such as cholesterol crystals, oxidized LDL, ATP or uric acids. Microparticles (MP) are extracellular vesicles that are released by activated or apoptotic cells. They are known as a vector for the intercellular transfer of biological information. The body of evidence indicates that endothelial microparticles contribute to the development and complications in atherosclerosis. With this study we sought to elucidate the effects microparticles, that are discharged by inflammasome activated endothelial cells, exert on arterial vascular cells.

Methods and results

RTPCR experiments showed that activation of human coronary artery endothelial cells (HCAEC) with LPS and Nigericin leads to NLRP3-inflammasome-specific upregulation of NLRP3 and IL1β. Analysis of the supernatant of aforementioned cells via westernblot revealed release of cleaved caspase-1 while donorcells undergo pyroptosis. FACS and electronmicroscopy experiments revealed time dependent release of endothelial microparticles (EMP) by inflammasome activated HCAEC, while western blot demonstrated that EMP enclose active caspase-1. Fluorescence microscopic imaging illustrated time dependent incorporation of EMP by HCAEC. Stimulation of HCAEC with EMP revealed detrimental biological effects on recipient cells as viability assay and scratch assay showed decreased viability and proliferation/ migration, cytotoxity assay showed increased cytotoxity and RT-PCR experiments showed increased expression of NALP3, IL-1b, VCAM and ICAM. The fact that treatment of recipient cells with the NLRP3-Inhibitor isoliquiritigenin (ILG), heat-inactivation of EMP and rupturing the EMP-membrane by freezing is able to diminish harmful effects EMP exert on recipient cells shown by viability assay, scratch assay and microscopic imaging underlines detrimental effects being exerted by EMP-encapsuled inflamasome-components.

Conclusion

Our findings verify that MP released from inflammasome-activated endothelial cells are incorporated by vascular cells which in turn sustain a reduction of cell viability, migration and proliferation. EMP effectuate activation of the NLRP3-inflammasme in their target cells. The cytotoxic effects of EMP are suppressed by inhibitors of the NLRP3-inflammasome and affection of EMP-membrane. Our results emphasize the immunological role of endothelial cells and indicate that inflammasome activation is transferable through microparticle-associated communication. This in turn facilitates cell death and possibly initiates a vicious cycle of inflammation suggesting a role in the advancement of atherosclerosis.

Acknowledgement/Funding

Else Kröner Scholarship

P3699Circulating pro-apoptotic microRNA-122 correlates with left ventricular function (LVEF) improvement after transcatheter aortic valve replacement and influence cardiomyocyte function via microvesicle

Background

Transcatheter aortic valve replacement (TAVR) is an established treatment option for high and intermediate risk patients with severe symptomatic aortic stenosis (AS). Whereas the majority of patients develop a left ventricular ejection fraction (LVEF) improvement after TAVR in response to TAVR-associated afterload reduction, around 50% of patients with reduced LVEF fail to develop LVEF improvement after TAVR. MicroRNAs (miRs) are novel biomarkers and effectors of myocardial (dys)function. We aimed to explore whether circulating miRs are differently regulated in response to TAVR in patients with or without postprocedural LV-function improvement.

Methods and results

96 patients who underwent TAVR were screened for inclusion into the study. Patients with impaired LVEF (<45%) were divided into three groups according to post-procedural LVEF development assessed 6 months after TAVR by transthoracic echocardiography: No LVEF improvement, LVEF-improvement of 0–15% and >15%. Plasma samples were obtained at 3 different time points: On the day before TAVR-procedure and at days 1 and 7 post-TAVR. Taqman miR array was performed in patients without LVEF improvement group and >15% LVEF improvement. The results showed that miR-122, miR-26a, miR-192, miR-483-5p, miR-720, miR-885-5p and miR-1274 were differently expressed when compared between day 1 and day 7. Based on literature, we also quantified four miRs related to LV function and fibrosis in our collective (miR-21, miR-145, miR-199, miR-30b). We validated these 14 circulating miRs levels and found that miR-122 level significantly increased at day 7 after TAVR in the no LVEF-improvement group. The increase of miR-122 negatively correlated with LVEF improvement at both day 7 (r=−0.237 and p=0.031) and 3 months (r=−0.323 and p=0.02) after TAVR. Within the 2-year follow-up, patients with lower level of miR-122 displayed a significantly reduced cardiovascular mortality (p=0.049). Next, vesicle degradation experiment and ultracentrifugation showed that miR-122 were mainly incorporated in microvesicles (MVs). In vitro, H202 increased miR-122 level in endothelial cells and endothelial-derived MV. Gain and Loss function experiments indicated elevated miR-122 level impaired migration and proliferation on HUVECs. Cardiomyocytes incubated with MVsmiR122-upregulated showed higher miR-122 expression than exosome miR122-upregulated or vesicle-free supernatant. Confocal microscopy confirmed the fluroscence-labeled EVs were absorbed by cardiomyocyte. Absorbed MVsmiR122-upregulated induced apoptosis of recipient cardiomyocytes.

Conclusion

Changes of circulating pro-apoptotic miR-122 levels significantly correlate with LVEF improvement after TAVR in low LVEF patients and might be suitable to predict the long term prognosis after TAVR in this set of patients. Microvesicles can mediate the transfer of miR-122 from endothelial cells to cardiomyocytes and further influence cardiomyocyte function.

P2583Endothelial cell-derived extracellular vesicles promote M2 polarization of THP-1 cells

Introduction

The intercellular transfer of biologically active molecules in extracellular vesicles (EVs) has recently been discovered as an important mechanism, which regulates cardiovascular health and disease. In the context of atherosclerosis, endothelial cell-derived EVs have been shown to modulate the phenotype of EV recipient cells in a relevant manner. Under pro-atherogenic conditions e.g. hyperglycemia, the export of numerous signal molecules in EVs is altered and so are EV-dependent effects on recipient cells. While the effect of endothelial-cell derived EVs on other endothelial cells and vascular smooth muscle cells is well characterized, little is known about the vesicle-based interaction of endothelial cells and monocytes under pro-atherogenic conditions. This is particularly relevant as monocytes are crucial modulators of vascular regeneration and inflammation. Our aim was therefore to investigate, whether EVs from endothelial cells have a significant effect on the differentiation and polarization of monocytes and how this process is affected by pathologic conditions as mentioned above.

Methods and results

Human Coronary Arterial Endothelial Cells (HCAECs) were cultured in high-Glucose-medium (30 mM) for 72h. PBS was used as a control. Large EVs were isolated from the culture supernatant by differential centrifugation (1 x 1500 g / 15 min + 2 x 2ehz748.0909 g / 40 min). The harvested large EVs were characterized by Immunoblotting, Nanoparticle Tracking Analysis as well as Transmission electron microscopy and were shown to be mostly between 80 and 500 nm in size. Specific surface markers including Annexin V and Flotillin-1 were highly enriched in the isolated EVs. The EVs were used for co-culture with THP-1 cells with and without previous phorbol-12-myristate-13-acetate (PMA) stimulation. After 4h as well as after 24 h of incubation with EVS, total RNA was isolated from the THP-1 cells and qPCR was performed to assess polarization towards M1 by TNF-α gene expression or M2 by IL-10 expression. While EV treatment of THP-1 cells without previous PMA-stimulation showed no measurable effect, a significant decrease in the expression of TNF-α was detected after 4 h of treatment from Glucose injured HCAECs. Similar results were obtained without glucose stimulation, the most significant reduction of TNF-α expression however was seen at 24 h. In regard to IL-10 no significant expression changes were detected in EV treated THP-1 cells.

Conclusion

We showed that glucose injury does not relevantly affect vesicle release or size. Furthermore, endothelial cell derived EVs cause a reduction of TNF-α expression, which indicates a polarization towards an M2 macrophage phenotype, irrespective of prior hyperglycaemic injury. As the M2 phenotype has been described as pro-regenerative, we conclude that endothelial cell derived EVs can exert a protective function during the invasion of monocytes in cardiovascular disease and remodeling.

P973Intravascular lithotripsy for lesion preparation in calcified coronary lesions: a prospective, observational, two-center registry

Background

Intravascular coronary lithotripsy (IVL) is a novel alternative treatment for heavily calcified lesions. This study sought to determine the strategy success and safety of IVL on calcified lesions in an all-comers cohort of patients.

Methods

Patients with moderate and severely calcified coronary lesions were screened in two centers in Spain and Germany starting April 2018. Until February 2019, 61 patients with 67 lesions were eligible for IVL. Patients were assigned to the following groups: A) Primary IVL therapy for patients with circumferential calcified de-novo coronary lesions (n=32), B) Secondary IVL therapy for patients with moderate or severe calcified coronary lesions in which conventional non-compliant balloon dilatation failed (n=18) and C) Tertiary IVL therapy in patients with in-stent stenosis due to stent underexpansion after previous stenting (n=17). Primary endpoint was strategy success and safety outcome. Strategy success was defined as successful stent delivery and expansion with attainment of <20% in-stent residual stenosis of the target lesion. Safety outcome were procedural complication, defined as coronary dissection, slow or no-reflow phenomenon, new coronary thrombus formation during PCI, abrupt vessel closure and device failure (inability to place the balloon, malfunction, or burst) and in hospital MACE.

Results

61 patients with 67 calcified lesions were treated with IVL. Mean diameter of calcified stenosis on quantitative coronary angiography was 72.02±13.8% at baseline and decreased to 17.7±15.84% (p-value: <0.01) after IVL with an acute gain of 1.9±0.63 mm. Mean minimal lumen diameter was 1.0±0.5 mm at baseline and increased after IVL to 2.9±0.6 mm. The overall average of applied pulses was 63±22. The primary endpoint of strategy success was reached overall in 85.2% of patients. 4 type b dissections (3 in group A, 1 in group B) were observed without further sequelae. There were no in-hospital MACE. In one patient (1.6%) non-ischemia driven target lesion failure was observed in routine follow up coronary angiography and was in need for revascularization. According to the subgroups, strategy success in primary IVL treatment (group A) and secondary IVL treatment (group B) was reached in 81.3% and 83.3% of cases, respectively. In tertiary IVL therapy (group C), the primary study endpoint was reached in 64.7% of cases. Device delivery and IVL treatment of target lesion could be performed in all lesions without vessel complications. 7 IVL balloons ruptured during treatment without any sequelae. Rupture was observed in most cases after repositioning of the balloon within the calcified lesion.

Conclusions

IVL provides a valid strategy for lesion preparation in severely calcified coronary lesions, with high success rate, and low procedural complication and MACE rates. Longitudinal studies will confirm if these favourable initial results of IVL-supported PCI are followed by good long-term results.

OS7.5 Healthcare utilization, medication use, and productivity loss in glioma patients with depressive symptoms and their family caregivers

BACKGROUND

Gliomas are associated with great societal burden through both direct (health and social care) and indirect (e.g., productivity loss) costs, but socioeconomic reports are scarce. We describe costs in a sample of glioma patients at high risk for depression and their family caregivers, and explore relationships between costs and treatable symptoms (depression; fatigue; cognitive complaints).

MATERIAL AND METHODS

Data from a nationwide randomised trial comparing internet-based therapy for depressive symptoms with waitlist controls were used.

Healthcare utilization, medication use, and productivity loss based on the

Trimbos/iMTA questionnaire for Costs associated with Psychiatric Illness (TIC-P) were described and costs in the past 4 weeks were calculated. Caregivers reported on their own costs and wellbeing

We used generalized linear regression models to predict costs using multiple observations per participant and robust standard errors. We included depressive symptoms (CES-D), fatigue (CIS), cognitive complaints (MOS), tumour grade (low-/high-grade), and disease status (stable/progression/active treatment).

RESULTS

Data from 91 glioma patients and 46 caregivers were used with multiple assessments from baseline through 12 months follow-up. Baseline data showed that over a 4 week period, 64.8% of patients (M=€394.99, sd=856.83) and 41.3% of caregivers (M=€131.11, sd=392.89) had used healthcare services. Medication was used by 90.1% of patients (M=€100.83, sd=191.07) and 43.5% of caregivers (M=€13.19, sd=21.03). Productivity loss resulted in M=€1231.19, sd=2185.35 for patients and M=€310.92, sd=841.36 for caregivers. In total, mean direct and indirect costs were €1632.22 (sd=2314.25) for patients and €447.85 (sd=1002.94) for caregivers. In patients, more depressive symptoms and cognitive complaints were associated with increased healthcare use costs; higher tumour grade and active disease were linked with higher medication costs (all p<.05). Active treatment was related to higher overall costs (p<.05). In caregivers, increased caregiver fatigue was associated with higher productivity loss and overall costs; more caregiver cognitive complaints were associated with higher total costs; higher tumour grade was associated with higher healthcare use and total costs; and patient active treatment was linked with higher healthcare use costs (all p<.05).

CONCLUSION

Direct and indirect costs are substantial in glioma patients and caregivers. This indicates that the true cost of brain tumours is a burden shared between patients, caregivers, the healthcare system, and society more widely. Tentative links between costs and symptoms of depression, fatigue, and cognitive complaints indicate that adequate support may lead to cost reductions. Multivariable regression models are currently being prepared.

Advancing interdisciplinary research in head and neck cancer through a multicenter longitudinal prospective cohort study: the NETherlands QUality of life and BIomedical Cohort (NET-QUBIC) data warehouse and biobank

Background

Worldwide, over 500,000 people are diagnosed with head and neck cancer each year, a disease with major impact on life expectancy and quality of life. The purpose of the Netherlands Quality of life and Biomedical Cohort study (NET-QUBIC) is to advance interdisciplinary research that aims to optimize diagnosis, treatment, and supportive care for head and neck cancer patients and their informal caregivers.

Methods

Using an extensive assessment protocol (electronic clinical record form, patient reported outcome measures and fieldwork (interviews and physical tests)), clinical data and data on quality of life, demographic and personal factors, psychosocial (depression, anxiety, fatigue, pain, sleep, mental adjustment to cancer, posttraumatic stress), physical (speech, swallowing, oral function, malnutrition, physical fitness, neurocognitive function, sexual function), lifestyle (physical activity, nutrition, smoking, alcohol, drugs), and social factors (social function, social support, work, health care use, and costs) are collected and stored in the data warehouse. A longitudinal biobank is built with tumor tissue, blood and blood components, saliva samples, and oral rinses. An infrastructure for fieldwork and laboratory protocols is established at all participating centers. All patients fill out patient reported outcome measures before treatment and at 3, 6, 12, 24, 36, 48, and 60 months follow-up. The interviews, physical tests and biological sample collection are at baseline and 6, 12, and 24 months follow-up. The protocol for caregivers includes blood sampling and oral rinses at baseline and a tailored list of questionnaires, administered at the same time points as the patients. In total, 739 HNC patients and 262 informal caregivers have been included in 5 out of the 8 HNC centers in the Netherlands.

Discussion

By granting access to researchers to the NET-QUBIC data warehouse and biobank, we enable new research lines in clinical (e.g. treatment optimization in elderly patients), biological (e.g. liquid biopsy analysis for relapse detection), health related quality of life (e.g. the impact of toxicity on quality of life), and interrelated research (e.g. health related quality of life in relation to biomarkers and survival).

Rigid Motion Correction for Brain PET/MR Imaging using Optical Tracking

A significant challenge during high-resolution PET brain imaging on PET/MR scanners is patient head motion. This challenge is particularly significant for clinical patient populations who struggle to remain motionless in the scanner for long periods of time. Head motion also affects the MR scan data. An optical motion tracking technique, which has already been demonstrated to perform MR motion correction during acquisition, is used with a list-mode PET reconstruction algorithm to correct the motion for each recorded event and produce a corrected reconstruction. The technique is demonstrated on real Alzheimer's disease patient data for the GE SIGNA PET/MR scanner.

The course of sexual interest and enjoyment in head and neck cancer patients treated with primary (chemo)radiotherapy

INTRODUCTION

The aim of this prospective study was to investigate the course of sexual interest and enjoyment in relation to sociodemographic and clinical factors, health-related quality of life (HRQOL), and symptoms of psychological distress in head and neck cancer (HNC) patients treated with primary (chemo)radiotherapy.

METHODS

HNC patients (n = 354) completed patient-reported outcome measures (PROMs) on HRQOL (EORTC QLQ-C30 and QLQ-H&N35, including the sexuality subscale covering less sexual interest and enjoyment), and psychological distress (HADS) pretreatment, at 6-week follow-up and at 3-, 6-, 12-, 18-, and 24-month follow-up (i.e., after treatment). Linear mixed models were used to analyze the course of sexuality from pretreatment to 24-month follow-up, and to investigate its relation to sociodemographic and clinical factors, HRQOL, and psychological distress as measured at baseline, and to investigate the course of sexuality from 6- to 24-month follow-up in relation to these factors measured at 6-month follow-up.

RESULTS

Before start of treatment, 37% of patients reported having less sexuality, which increased to 60% at 6-week follow-up, and returned to baseline level from 12-month follow-up onwards. Older age (p = 0.037) and trouble with social contact (p < 0.001), weight loss (p = 0.013), and constipation (p = 0.041) before treatment were associated with less sexuality over time. Female gender (p = 0.021) and poor social functioning (p < 0.001) at 6-month follow-up were associated with less sexuality from 6- to 24-month follow-up.

DISCUSSION

Less sexuality is often reported in HNC patients treated with (chemo)radiotherapy. Using PROMs in clinical practice may help identify patients who might benefit from supportive care targeting sexuality.