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57 result(s) for "Moll, Annette C."
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Trilateral retinoblastoma: a systematic review and meta-analysis
About 5% of children with retinoblastoma from germline mutation of the RB1 gene are at risk of developing trilateral retinoblastoma—intraocular retinoblastoma combined with a histologically similar brain tumour, most commonly in the pineal gland. We aimed to provide a systematic overview of published data for trilateral retinoblastoma, and to analyse how survival has changed. We searched Medline and Embase for scientific literature published between Jan 1, 1966, and April 14, 2014, that assessed trilateral retinoblastoma cases. We undertook a meta-analysis of survival with the Kaplan-Meier method and Cox proportional hazards regression, stratified on the basis of the original study, to account for between-study heterogeneity. We included 90 studies, with 174 patients with trilateral retinoblastoma. 5-year survival after pineal trilateral retinoblastoma increased from 6% (95% CI 2–15) in patients diagnosed before 1995, to 44% (26–61; p<0·0001) in those diagnosed from 1995 onwards. Before 1995, no patients with non-pineal trilateral retinoblastoma survived, but from 1995 onwards, 5-year survival was 57% (30–77; p=0·035). Hazard ratios (HR) adjusted for the presence of leptomeningeal metastases and trilateral retinoblastoma location, suggested that both conventional (HR 0·059, 95% CI 0·016–0·226; p<0·0001) and high-dose chemotherapy with stem-cell rescue (0·013, 0·002–0·064; p<0·0001) most strongly contributed to this improvement. Absence of leptomeningeal metastases (HR 2·13, 95% CI 0·98–4·60; p=0·055) were associated with improved survival. Non-pineal trilateral retinoblastomas were larger than pineal tumours (median 30 mm [range 6–100] vs 22 mm [7–60]; p=0·012), but both had similar outcomes since 1995. Our results suggest that improvements in overall survival are attributable to improved chemotherapy regimens and early detection of pineal trilateral retinoblastoma. As such, successful treatment of trilateral retinoblastoma should include screening at least at the time of retinoblastoma diagnosis and chemotherapy, which would preferably be a high-dose regimen with autologous stem-cell rescue. None.
A Meta-Analysis of Retinoblastoma Copy Numbers Refines the List of Possible Driver Genes Involved in Tumor Progression
While RB1 loss initiates retinoblastoma development, additional somatic copy number alterations (SCNAs) can drive tumor progression. Although SCNAs have been identified with good concordance between studies at a cytoband resolution, accurate identification of single genes for all recurrent SCNAs is still challenging. This study presents a comprehensive meta-analysis of genome-wide SCNAs integrated with gene expression profiling data, narrowing down the list of plausible retinoblastoma driver genes. We performed SCNA profiling of 45 primary retinoblastoma samples and eight retinoblastoma cell lines by high-resolution microarrays. We combined our data with genomic, clinical and histopathological data of ten published genome-wide SCNA studies, which strongly enhanced the power of our analyses (N = 310). Comprehensive recurrence analysis of SCNAs in all studies integrated with gene expression data allowed us to reduce candidate gene lists for 1q, 2p, 6p, 7q and 13q to a limited gene set. Besides the well-established driver genes RB1 (13q-loss) and MYCN (2p-gain) we identified CRB1 and NEK7 (1q-gain), SOX4 (6p-gain) and NUP205 (7q-gain) as novel retinoblastoma driver candidates. Depending on the sample subset and algorithms used, alternative candidates were identified including MIR181 (1q-gain) and DEK (6p gain). Remarkably, our study showed that copy number gains rarely exceeded change of one copy, even in pure tumor samples with 100% homozygosity at the RB1 locus (N = 34), which is indicative for intra-tumor heterogeneity. In addition, profound between-tumor variability was observed that was associated with age at diagnosis and differentiation grades. Since focal alterations at commonly altered chromosome regions were rare except for 2p24.3 (MYCN), further functional validation of the oncogenic potential of the described candidate genes is now required. For further investigations, our study provides a refined and revised set of candidate retinoblastoma driver genes.
Characterisation of retinoblastomas without RB1 mutations: genomic, gene expression, and clinical studies
Retinoblastoma is the childhood retinal cancer that defined tumour-suppressor genes. Previous work shows that mutation of both alleles of the RB1 retinoblastoma suppressor gene initiates disease. We aimed to characterise non-familial retinoblastoma tumours with no detectable RB1 mutations. Of 1068 unilateral non-familial retinoblastoma tumours, we compared those with no evidence of RB1 mutations (RB1+/+) with tumours carrying a mutation in both alleles (RB1−/−). We analysed genomic copy number, RB1 gene expression and protein function, retinal gene expression, histological features, and clinical data. No RB1 mutations (RB1+/+) were reported in 29 (2·7%) of 1068 unilateral retinoblastoma tumours. 15 of the 29 RB1+/+ tumours had high-level MYCN oncogene amplification (28–121 copies; RB1+/+MYCNA), whereas none of 93 RB1−/− primary tumours tested showed MYCN amplification (p<0·0001). RB1+/+MYCNA tumours expressed functional RB1 protein, had fewer overall genomic copy-number changes in genes characteristic of retinoblastoma than did RB1−/− tumours, and showed distinct aggressive histological features. MYCN amplification was the sole copy-number change in one RB1+/+MYCNA retinoblastoma. One additional MYCNA tumour was discovered after the initial frequencies were determined, and this is included in further analyses. Median age at diagnosis of the 17 children with RB1+/+MYCNA tumours was 4·5 months (IQR 3·5–10), compared with 24 months (15–37) for 79 children with non-familial unilateral RB1−/− retinoblastoma. Amplification of the MYCN oncogene might initiate retinoblastoma in the presence of non-mutated RB1 genes. These unilateral RB1+/+MYCNA retinoblastomas are characterised by distinct histological features, only a few of the genomic copy-number changes that are characteristic of retinoblastoma, and very early age of diagnosis. National Cancer Institute–National Institutes of Health, Canadian Institutes of Health Research, German Research Foundation, Canadian Retinoblastoma Society, Hyland Foundation, Toronto Netralaya and Doctors Lions Clubs, Ontario Ministry of Health and Long Term Care, UK-Essen, and Foundations Avanti-STR and KiKa.
Multi-view convolutional neural networks for automated ocular structure and tumor segmentation in retinoblastoma
In retinoblastoma, accurate segmentation of ocular structure and tumor tissue is important when working towards personalized treatment. This retrospective study serves to evaluate the performance of multi-view convolutional neural networks (MV-CNNs) for automated eye and tumor segmentation on MRI in retinoblastoma patients. Forty retinoblastoma and 20 healthy-eyes from 30 patients were included in a train/test (N = 29 retinoblastoma-, 17 healthy-eyes) and independent validation (N = 11 retinoblastoma-, 3 healthy-eyes) set. Imaging was done using 3.0 T Fast Imaging Employing Steady-state Acquisition (FIESTA), T2-weighted and contrast-enhanced T1-weighted sequences. Sclera, vitreous humour, lens, retinal detachment and tumor were manually delineated on FIESTA images to serve as a reference standard. Volumetric and spatial performance were assessed by calculating intra-class correlation (ICC) and dice similarity coefficient (DSC). Additionally, the effects of multi-scale, sequences and data augmentation were explored. Optimal performance was obtained by using a three-level pyramid MV-CNN with FIESTA, T2 and T1c sequences and data augmentation. Eye and tumor volumetric ICC were 0.997 and 0.996, respectively. Median [Interquartile range] DSC for eye, sclera, vitreous, lens, retinal detachment and tumor were 0.965 [0.950–0.975], 0.847 [0.782–0.893], 0.975 [0.930–0.986], 0.909 [0.847–0.951], 0.828 [0.458–0.962] and 0.914 [0.852–0.958], respectively. MV-CNN can be used to obtain accurate ocular structure and tumor segmentations in retinoblastoma.
Associations Between Retinal Microvascular Changes and Dementia, Cognitive Functioning, and Brain Imaging Abnormalities: A Systematic Review
Retinal microvascular changes can be visualized noninvasively and have been associated with cognitive decline and brain changes in relation to aging and vascular disease. We systematically reviewed studies, published between 1990 and November 2012, on the association between retinal microvascular changes and dementia, cognitive functioning, and brain imaging abnormalities, in the context of aging and vascular risk factors. In cross-sectional studies (k = 26), retinal microvascular changes were associated with the presence of dementia (range of odds ratios (ORs) 1.17;5.57), with modest decrements in cognitive functioning in nondemented people (effect sizes -0.25;0.03), and with brain imaging abnormalities, including atrophy and vascular lesions (ORs 0.94;2.95). Longitudinal studies were more sparse (k = 9) and showed no consistent associations between retinal microvascular changes and dementia or cognitive dysfunctioning 3 to 15 years later (ORs and hazard ratios 0.77;1.55). However, there were indications of prospective associations with brain imaging abnormalities ((ORs) 0.81;3.19). In conclusion, particularly in cross-sectional studies there is a correlation between retinal microvascular changes and dementia, cognitive impairment, and brain imaging abnormalities. Associations are strongest for more severe retinal microvascular abnormalities. Retinal microvascular abnormalities may offer an important window on the brain for etiological studies.
Somatic genomic alterations in retinoblastoma beyond RB1 are rare and limited to copy number changes
Retinoblastoma is a rare childhood cancer initiated by RB1 mutation or MYCN amplification, while additional alterations may be required for tumor development. However, the view on single nucleotide variants is very limited. To better understand oncogenesis, we determined the genomic landscape of retinoblastoma. We performed exome sequencing of 71 retinoblastomas and matched blood DNA. Next, we determined the presence of single nucleotide variants, copy number alterations and viruses. Aside from RB1 , recurrent gene mutations were very rare. Only a limited fraction of tumors showed BCOR (7/71, 10%) or CREBBP alterations (3/71, 4%). No evidence was found for the presence of viruses. Instead, specific somatic copy number alterations were more common, particularly in patients diagnosed at later age. Recurrent alterations of chromosomal arms often involved less than one copy, also in highly pure tumor samples, suggesting within-tumor heterogeneity. Our results show that retinoblastoma is among the least mutated cancers and signify the extreme sensitivity of the childhood retina for RB1 loss. We hypothesize that retinoblastomas arising later in retinal development benefit more from subclonal secondary alterations and therefore, these alterations are more selected for in these tumors. Targeted therapy based on these subclonal events might be insufficient for complete tumor control.
Worldwide Enucleation Techniques and Materials for Treatment of Retinoblastoma: An International Survey
To investigate the current practice of enucleation with or without orbital implant for retinoblastoma in countries across the world. A digital survey identifying operation techniques and material used for orbital implants after enucleation in patients with retinoblastoma. We received a response of 58 surgeons in 32 different countries. A primary artificial implant is routinely inserted by 42 (72.4%) surgeons. Ten (17.2%) surgeons leave the socket empty, three (5.2%) decide per case. Other surgeons insert a dermis fat graft as a standard primary implant (n=1), or fill the socket in a standard secondary procedure (n=2; one uses dermis fat grafts and one artificial implants). The choice for porous implants was more frequent than for non-porous implants: 27 (58.7%) and 15 (32.6%), respectively. Both porous and non-porous implant types are used by 4 (8.7%) surgeons. Twenty-five surgeons (54.3%) insert bare implants, 11 (23.9%) use separate wrappings, eight (17.4%) use implants with prefab wrapping and two insert implants with and without wrapping depending on type of implant. Attachment of the muscles to the wrapping or implant (at various locations) is done by 31 (53.4%) surgeons. Eleven (19.0%) use a myoconjunctival technique, nine (15.5%) suture the muscles to each other and seven (12.1%) do not reattach the muscles. Measures to improve volume are implant exchange at an older age (n=4), the use of Restylane SQ (n=1) and osmotic expanders (n=1). Pegging is done by two surgeons. No (worldwide) consensus exists about the use of material and techniques for enucleation for the treatment of retinoblastoma. Considerations for the use of different techniques are discussed.
The EMIF-AD PreclinAD study: study design and baseline cohort overview
Background Amyloid pathology is the pathological hallmark in Alzheimer’s disease (AD) and can precede clinical dementia by decades. So far it remains unclear how amyloid pathology leads to cognitive impairment and dementia. To design AD prevention trials it is key to include cognitively normal subjects at high risk for amyloid pathology and to find predictors of cognitive decline in these subjects. These goals can be accomplished by targeting twins, with additional benefits to identify genetic and environmental pathways for amyloid pathology, other AD biomarkers, and cognitive decline. Methods From December 2014 to October 2017 we enrolled cognitively normal participants aged 60 years and older from the ongoing Manchester and Newcastle Age and Cognitive Performance Research Cohort and the Netherlands Twins Register. In Manchester we included single individuals, and in Amsterdam monozygotic twin pairs. At baseline, participants completed neuropsychological tests and questionnaires, and underwent physical examination, blood sampling, ultrasound of the carotid arteries, structural and resting state functional brain magnetic resonance imaging, and dynamic amyloid positron emission tomography (PET) scanning with [ 18 F]flutemetamol. In addition, the twin cohort underwent lumbar puncture for cerebrospinal fluid collection, buccal cell collection, magnetoencephalography, optical coherence tomography, and retinal imaging. Results We included 285 participants, who were on average 74.8 ± 9.7 years old, 64% female. Fifty-eight participants (22%) had an abnormal amyloid PET scan. Conclusions A rich baseline dataset of cognitively normal elderly individuals has been established to estimate risk factors and biomarkers for amyloid pathology and future cognitive decline.
Diabetes and diabetic retinopathy in people aged 50 years and older in the Republic of Suriname
Background/AimsPopulation-based surveys on diabetes and diabetic retinopathy (DR) are necessary to increase awareness and develop screening and therapeutic programmes. The aim was to estimate the prevalence of DR in older adults of different ethnic backgrounds in Suriname.MethodsFifty clusters of 60 people aged ≥50 years were randomly selected with a probability proportional to the size of the population unit. Eligible people were randomly selected through compact segment sampling and examined using the Rapid Assessment of Avoidable Blindness plus Diabetic Retinopathy (RAAB + DR) protocol. Participants were classified as having diabetes if they: were previously diagnosed with diabetes; were receiving treatment for glucose control; had a random blood glucose level >200 mg/dL. These participants were dilated for funduscopy, assessed for DR following the Scottish DR grading protocol and evaluated for ethnicity and DR ophthalmic screening frequencies.ResultsA total of 2806 individuals was examined (response 93.6%). The prevalence of diabetes was 24.6%. In these patients any type of DR and/or maculopathy occurred in 21.6% and sight-threatening DR in 8.0%. Of the known diabetics, 34.2% never had an eye examination for DR and in 13.0% the last examination was >24 months ago. The prevalence of diabetes was significantly higher in Hindustani people compared with other major ethnic groups.ConclusionsThe prevalence of diabetes and diabetics without regular DR control in people aged ≥50 years in Suriname was higher than expected. The uptake for special services for DR has to be expanded to decrease patient delay and DR-induced blindness.
Concurrence of sleep problems and distress: prevalence and determinants in parents of children with cancer
Background: Parents of children with cancer are at risk for sleep problems. If these problems persist, an important perpetuating factor might be ongoing parental distress. Objective: The aim of this study is to assess the prevalence of sleep problems and the concurrence with distress in parents of children treated for cancer, and to identify predictors of this symptom clustering. Method: Parents completed the Medical Outcomes Study (MOS) Sleep Scale and Distress Thermometer for Parents (DT-P). Clinically relevant sleep problems were defined as a score >1SD above the norm and clinical distress as a thermometer score above the established cut-off of 4. Four parent categories were constructed: neither sleep problems nor distress; no distress but sleep problems; no sleep problems but distress; both sleep problems and distress. Predictive determinants (sociodemographic, medical, psychosocial) for each category were assessed with multilevel multinomial logistic regression. Results: Parents (202 mothers and 150 fathers) of 231 children with different cancers participated. Mean time since diagnosis was 3.3 ± 1.4 years (90% off-treatment). The prevalence of sleep problems was 37%. Fifty percent of parents reported neither sleep problems nor distress, 9% had only sleep problems, 13% only distress, and 28% reported both. Compared to parents without sleep problems or distress, parents who reported both were more likely to report parenting problems (OR 4.4, [2.2-9.1]), chronic illness (OR 2.8, [1.2-6.5]), insufficient social support (OR 3.7, [1.5-9.1]), pre-existent sleep problems (OR 6.2, [2.0-18.6]) and be female (OR 1.8, [1.1-4.2]). Conclusions: Sleep problems are common in parents of children treated for cancer, and occur mostly in the presence of clinical distress. Future research must show which interventions are most effective in this group: mainly targeted at sleep improvement or with prominent roles for stress management or trauma processing. * Pediatric cancer diagnoses are traumatic for parents and can precipitate insomnia. If insomnia persists, an important perpetuating factor might be ongoing distress.* This study in 352 parents of children treated for cancer shows a high prevalence (37%) of sleep problems, in the majority of parents occurring in concurrence with clinical distress. Several predictors were identified.* Future research should reveal which interventions are most effective: targeted at sleep improvement, or at stress management and trauma processing.