Predictive Testing Research Articles

PTEN hamartoma tumour syndrome: what happens when there is no PTEN germline mutation?

Hereditary cancer syndromes represent ~10% of all incident cancers. It is important to identify individuals having these disorders because, unlike patients with sporadic cancer, these patients require specialised life-long care, with implications for their families. Importantly, the identification of alterations in cancer-predisposing genes facilitates gene-informed molecular diagnosis, cancer risk assessment and gene-specific clinical management. Moreover, knowledge about gene function in the inherited cancers offers insights towards biological processes pertinent to the more common sporadic cancers. Conversely, without a known gene, clinical management is less precise, and it is impossible to offer predictive testing of family members. PTEN hamartoma tumour syndrome (PHTS) is an umbrella term encompassing four overgrowth and cancer predisposition disorders associated with germline PTEN mutations. With time, it became evident that only a finite subset of individuals with PHTS-associated phenotypes harbour germline PTEN mutations. Therefore, non-PTEN aetiologies exist in PTEN wildtype patients. Indeed, gene discovery efforts over the last decade elucidated multiple candidate cancer predisposition genes. While a subset of genes (e.g. AKT1, PIK3CA) are biologically plausible as being key effectors within the PTEN signalling cascade, other genes required meticulous functional interrogation to explain their contribution to PHTS-related phenotypes. Collectively, the extensive phenotypic heterogeneity of the clinical syndromes typically united by PTEN is reflected by the genetic heterogeneity revealed through gene discovery. Validating these gene discoveries is critical because, while PTEN wildtype patients can be diagnosed clinically, they do not have the benefit of specific gene-informed risk assessment and subsequent management.

Cancer Surveillance in Healthy Carriers of Germline Pathogenic Variants in BRCA1/2: A Review of Secondary Prevention Guidelines.

Germline pathogenic alterations in the breast cancer susceptibility genes 1 (BRCA1) and 2 (BRCA2) are the most prevalent causes of hereditary breast and ovarian cancer. The increasing trend in proportion of cancer patients undergoing genetic testing, followed by predictive testing in families of new index patients, results in a significant increase of healthy germline BRCA1/2 mutation carriers who are at increased risk for breast, ovarian, and other BRCA-related cancers. This review aims to give an overview of available screening guidelines for female and male carriers of pathogenic or likely pathogenic germline BRCA1/2 variants per cancer type, incorporating malignancies that are more or less recently well correlated with BRCA1/2. We selected guidelines from national/international organizations and/or professional associations that were published or updated between January 1, 2015, and February 1, 2020. In total, 12 guidelines were included. This review reveals several significant discordances between the different guidelines. Optimal surveillance strategies depend on accurate age-specific cancer risk estimates, which are not reliably available for all BRCA-related cancers. Up-to-date national or international consensus guidelines are of utmost importance to harmonize counseling and proposed surveillance strategies for BRCA1/2 carriers.

Open Source Cross-Sectional Asset Pricing

We provide data and code that successfully reproduces nearly all crosssectional stock return predictors. Unlike most metastudies, we carefully examine the original papers to determine whether our predictability tests should produce t-stats above 1.96. For the 180 predictors that were clearly significant in the original papers, 98% of our reproductions find t-stats above 1.96. For the 30 predictors that had mixed evidence, our reproductions find t-stats of 2 on average. We include an additional 105 characteristics and 945 portfolios with alternative rebalancing frequencies to nest variables used in other metastudies. Our data covers all portfolios in Hou, Xue and Zhang (2017); 98% of the portfolios in McLean and Pontiff (2016); 90% of the characteristics from Green, Hand, and Zhang (2017); and 90% of the firm-level predictors in Harvey, Liu, and Zhu (2016) that use widelyavailable data.

Advances in the thermal and petrologic modeling of subduction zones

AbstractIn the two decades since Subduction: Top to Bottom was published in 1996, improved analytical and numerical thermal-petrologic models of subduction zones have been constructed and evaluated against new seismological and geological observations. Advances in thermal modeling include a range of new approaches to incorporating shear (frictional, viscous) heating along the subduction interface and to simulating induced flow in the mantle wedge. Forearc heat-flux measurements constrain the apparent coefficient of friction (μ′) along the plate interface to <∼0.1, but the extent to which μ′ may vary between subduction zones remains challenging to discern owing to scatter in the heat-flux measurements and uncertainties in the magnitude and distribution of radiogenic heat production in the overriding crust. Flow in the mantle wedge and the resulting thermal structure depend on the rheology of variably hydrated mantle rocks and the depth at which the subducting slab becomes coupled to the overlying mantle wedge. Advances in petrologic modeling include the incorporation of sophisticated thermodynamic software packages into thermal models and the prediction of seismic velocities from mineralogic and petrologic models. Current thermal-petrologic models show very good agreement between the predicted location of metamorphic dehydration reactions and observed intermediate-depth earthquakes, and between the predicted location of the basalt-to-eclogite transition in subducting oceanic crust and observed landward-dipping, low-seismic-velocity layers. Exhumed high-pressure, low-temperature metamorphic rocks provide insight into subduction-zone temperatures, but important thermal parameters (e.g., convergence rate) are not well constrained, and metamorphic rocks exposed at the surface today may reflect relatively warm conditions in the past associated with subduction initiation or ridge subduction. We can anticipate additional advances in our understanding of subduction zones as a result of further testing of model predictions against geologic and geophysical observations, and of evaluating the importance of advective processes, such as diapirism and subduction-channel flow, that are not captured in hybrid kinematic-dynamic models of subduction zones but are observed in fully dynamical models under certain conditions.

Human Genetics Society of Australasia Position Statement: Predictive and Presymptomatic Genetic Testing in Adults and Children.

In 2020, the Human Genetics Society of Australasia released its Position Statement on Predictive and Presymptomatic Genetic Testing in Adults and Children. This Position Statement synthesizes the major practical, psychosocial and ethical considerations associated with presymptomatic and predictive genetic testing in adults who have the capacity to make a decision, children and young people who lack capacity and adults living with reduced or fluctuating capacity. Recommendations include that predictive testing in adults, young people and children should only be offered with pretest genetic counseling and the option of posttest genetic counseling. An individual considering (for themselves or on behalf of another) whether to have a predictive test should also be supported to allow them to make an autonomous and informed decision. Predictive testing should only be offered to children and young people for conditions where there is likely to be a direct medical benefit to them through surveillance, use of prevention strategies or other medical interventions in the immediate future. Where symptoms are likely to develop in childhood, in the absence of options to implement surveillance or risk reduction measures, genetic health professionals and parents/guardians should discuss whether undertaking predictive testing is the best course of action for the child and the family as a whole. Where symptoms are likely to develop in adulthood, the default position should be to postpone predictive testing until the young person achieves the capacity to make their own autonomous and informed decision.

Immunocytochemistry of cytology specimens for predictive biomarkers in lung cancer.

With a growing number of predictive biomarkers that have emerged in non-small cell lung carcinoma (NSCLC), there has been a paradigm shift in the management of these patients. Of the various predictive biomarker testing methods, immunohistochemistry (IHC) is the most widely available, cost-effective, and commonly used methods. However, most predictive IHC assays are validated primarily on formalin-fixed paraffin-embedded (FFPE) histologic tissue samples and translating these assays to cytologic specimens requires additional and rigorous validation. This is part due to the lack of standardized processing protocols in cytology resulting in a variety of preanalytic variables that can impact the antigenicity of antibodies used for predictive biomarker testing. The review article discusses the various preanalytical and analytical factors that impact immunocytochemistry (ICC) in cytologic specimens and summarizes the current published literature on ALK, ROS1, PD-L1, and other predictive biomarker ICC in cytology.

Huntington's disease and Sydenham's chorea

Huntington's disease was an important example for discussing the problem of predictive genetic testing. Like other movement disorders, it includes non-motor symptoms and a prodromal phase. As a rapidly progressive monogenetic disease, it is an important model disease for the study of neurodegenerative pathomechanisms and one of the first movement disorders for which causal therapies seem to be reachable.

Abstract A02: Patient-derived xenograft models of neuroblastoma as improvement for the prediction of targeted therapies for childhood cancer

Abstract Introduction: Highly variable clinical outcomes including immediate fatal progression to spontaneous regression are characteristically observed for neuroblastoma (NB), a pediatric cancer arising from progenitors of the sympathetic nervous system. Pronounced rates of relapse and fast-evolving resistance against standard-of-care (SOC) treatments, together with a high degree of mutational mobility and heterogeneity, indicate the need for more precise and molecular targeted strategies. Aim: Patient-derived xenograft (PDX) models closely resemble human tumor biology from primary tissue and could be utilized for predictive preclinical testing. For this aim we established a cohort of 10 NB PDX models from 33 primary human tissue samples obtained from the Charité University Clinic. Specimen originated from proliferating areas while possible necrotic lesions had been removed prior to subcutaneous transplantation to immunodeficient NOG mice. After documenting stable growth over 3-4 initial passages, NB PDX models were screened for sensitivity to SOC drugs including actinomycin D, dacarbazine, docetaxel, doxorubicin, etoposide, ifosfamide, gemcitabine, and vincristine. Results: Characteristic NB pathology of all PDX was verified using HE and IHC staining of FFPE tumor sections comparing individual passages. Post-transplant lymphoproliferative disorder (PTLD) was excluded analyzing hCD45 specific marker. Depending on traceable somatic mutations, NB PDX doubling times dramatically varied between 4 days in aggressive, 8 days in intermediate, and up to 18 days in slowly growing tumors. Not surprisingly, high-risk NB tumors with confirmed MYCN amplification and ALK mutation exhibited the fastest growth in our cohort. In contrast, doubling rates of tumors with single ALK mutation or TERT rearrangement were not significantly different compared to the slowest PDX models without driver mutations. Most effective treatment response was observed for vincristine, leading to stable disease or partial regression in 5 out of 8 models (63%) achieving a tumor growth inhibition (TGI) of 70%, whereas all models were insensitive against dacarbazine treatment with a TGI of 33%, respectively. Conclusion: Currently, whole-exome sequencing of all models is performed. Molecular analysis will enable prediction of more precise therapeutic strategies. We will use our NB PDX to validate targeted treatment effects of recent pipeline drugs. As part of the European Innovative Therapies for Children with Cancer-Paediatric Preclinical Proof of Concept Platform (ITCC-P4) consortium, these findings will be correlated with predictions of the NB PDX molecular profile to achieve valuable benefit for pediatric patients. Citation Format: Dennis Gürgen, Jana Rolff, Johannes H. Schulte, Hedwig E. Deubzer, Karin Schmelz, Anton G. Henssen, Patrick Hundsdörfer, Georg Seifert, Angelika Eggert, Wolfgang Walther, Jens Hoffmann. Patient-derived xenograft models of neuroblastoma as improvement for the prediction of targeted therapies for childhood cancer [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A02.

Small-sample tests for stock return predictability with possibly non-stationary regressors and GARCH-type effects

We develop a simulation-based procedure to test for stock return predictability with multiple regressors. The process governing the regressors is left completely free and the test procedure remains valid in small samples even in the presence of non-normalities and GARCH-type effects in the stock returns. The usefulness of the new procedure is demonstrated in a simulation study and by examining the ability of a group of financial variables to predict excess stock returns. We find some evidence of predictability during the period 1948–2014, driven entirely by the term spread. This empirical evidence, however, is much weaker over subsamples.

A machine learning-based approach for the inference of immunotherapy biomarker status in lung adenocarcinoma from hematoxylin and eosin (H&E) histopathology images.

3122 Background: The current standard work-up for both diagnosis and predictive biomarker testing in metastatic non-small cell lung cancer (NSCLC), can exhaust an entire tumor specimen. Notably, gene mutation panels or tumor mutation burden (TMB) testing currently requires 10 tissue slides and ranges from 10 days to 3 weeks from sample acquisition to test result. As more companion diagnostic (CDx)-restricted drugs are developed for NSCLC, rapid, tissue-sparing tests are sorely needed. We investigated whether TMB, T-effector (TEFF) gene signatures and PD-L1 status can be inferred from H&E images alone using a machine learning approach. Methods: Algorithm development included two steps: First, a neural network was trained to segment hand-annotated, pathologist-confirmed biological features from H&E images, such as tumor architecture and cell types. Second, these feature maps were fed into a classification model to predict the biomarker status. Ground truth biomarker status of the H&E-associated tumor samples came from whole exome sequencing (WES) for TMB, RNAseq for the TEFF gene signatures or reverse-phase protein array for PD-L1. Digital H&E images of NSCLC adenocarcinoma for model development were obtained from the cancer genome atlas (TCGA) and commercial sources. Results: This approach achieves > 75% accuracy in predicting TMB, TEFF and PD-L1 status, offers a way to interpret the model, and provides biological insights into the tumor-host microenvironment. Conclusions: These findings suggest that biomarker inference from H&E images is feasible, and may be sufficiently accurate to supplement or replace current tissue-based tests in a clinical setting. Our approach utilizes biological features for inference, and is thus robust, interpretable, and readily verifiable by pathologists. Finally, biomarker status inference from a single H&E image may enable testing in patients whose tumor tissue has been exhausted, spare further tissue use, and return test results within hours to enable rapid treatment decision-making to maximize patient benefit.

Healthcare disparities and the demand for expanding hereditary breast cancer screening guidelines in African Americans.

e13636 Background: The role of predictive genetic testing on cancer care continues to rise in the healthcare community due to increased development, high demand and utilization of multi-panel testing and genome sequencing. BRCA1 and BRCA2 (BRCA1/2) mutations constitute some of the most common, targetable and clinically important markers in breast cancer. Individuals who harbor BRCA1/2 mutation have a substantially increased risk of developing a multitude of cancers, including breast and ovarian cancer. Early detection of these mutations leads to genetic and prevention counselling. The National Comprehensive Cancer Network (NCCN) guidelines recommend BRCA1/2 screening in high risk individuals however has not incorporated differences within ethnic cohorts. Methods: This study reviewed data collected from a genetics clinic in a tertiary community hospital from 2008 to 2018 to analyze the prevalence of BRCA1/2 mutations in various ethnicities as well as identify high risk personal characteristics and family history. A retrospective chart analysis was conducted on 1090 high risk patients seen for genetic counselling for hereditary breast and ovarian cancer syndrome. Results: Among cases, BRCA1/2 mutations were significantly more common in African American when compared to non-Ashkenazi Jewish Caucasians (8.1% vs 3.6%, p = 0.020). African Americans were more likely to have a personal history of any cancer compared to non-Ashkenazi Jewish Caucasians (90.4% vs 84.5 %, p = 0.048). African Americans were also more likely to have personal history of breast cancer compared to non-Ashkenazi Jewish Caucasians (86.4% vs 79.6%, p = 0.048). Regarding family history, there was no significant difference in the prevalence of cancer. Conclusions: In conclusion, we observed a significantly higher rate of BRCA1/2 in the African American population when compared to non-Ashkenazi Jewish Caucasians. Given the documented social barriers such as insurance and lack of knowledge of family history, the prevalence of BRCA1/2 might be underrepresented in literature. It is critical for healthcare providers to assess probability of BRCA1/2 mutations in the African American population and consequently order genetic testing when appropriate. Future studies are needed in this ethnic cohort to establish if a more tailored approach would help identify higher risk individuals.

HER2 heterogeneity in adenocarcinoma of the distal esophagus and stomach.

4567 Background: Patients with HER2 positive adenocarcinoma of the esophagus or stomach are eligible for HER2 targeted therapy, which can improve survival in selected patients. Previous research shows that HER2 gene amplification and HER2 overexpression is frequently heterogeneous within these tumors. Biopsies taken from heterogeneous tumors for predictive testing may therefore result in false-negative outcomes. The objective of this study was to assess HER2 amplification and expression in biopsies and paired resection specimens with adenocarcinoma of the esophagus or stomach, from patients who did not receive neoadjuvant systemic therapy. Methods: Paired biopsies and resection specimens of patients with adenocarcinomas of the esophagus or stomach were retrospectively selected. Immunostaining was performed on all samples using antibody 4B5 (Ventana Medical Systems) and Silver-In-Situ-Hybridization was performed in selected cases. Scoring for HER2 was performed according to the method described by Hofmann et al. (2008). Results: We included 378 cases for analysis. In both biopsies and resection specimens 14% of the cases were HER2 positive. Intratumor heterogeneity in HER2 positive tumors was present in 45% ( n= 24/53) in biopsies and 75% ( n= 39/52) in resection specimens. In HER2 positive resection specimens, 65% ( n= 34/52) of paired biopsies were also positive. In the 18 remaining discordant tumors (resection HER2 positive, biopsy negative), intratumor heterogeneity was present in 16/18 cases. For HER2 negative resection specimens all paired biopsies were also HER2 negative. SISH was performed in 110 tumors. Agreement of HER2 gene amplification between biopsy and resection specimens was observed in 86% (n = 95/110). Five HER2 negative biopsies were positive in the resection specimen. Conclusions: The results of this study indicate that predictive HER2 assessment in adenocarcinoma of the esophagus or stomach can lead to false negative results based on biopsies. As a result, patients with HER2 positive tumors can unintentionally be denied neoadjuvant HER2 targeted therapy. The set of patients investigated in this present study is unique because of the absence of any systemic and/or radiation therapy between the biopsy and the resection of the tumor. Hopefully these results can help in developing methods for improved patient selection for HER2 targeted therapy.

Immunofocus-PD-L1 high throughput quantitative next generation sequencing assay.

e13521 Background: Immunohistochemical (IHC) assays are presently used as the gold standard predictive tests for immunotherapy but are compromised due to a number of potential variables. Comparative studies have demonstrated differing levels of PD-L1 staining between assays which appears independent of the antibody binding epitope. Secondly, inter-reader reliability even between expert pathologists is problematic particularly for assessment of PD-L1 positive immune cell populations. Methods: To improve predictive testing for anti PD-L1/PD1 immunotherapies we have developed and validated a Next Generation Sequencing Platform, Immunofocus, able to perform high-throughput quantitative PD-L1 gene expression levels in routine diagnostic PWET biopsies. We applied Immunofocus to a cohort of 130 NSCLCs and compared PD-L1 gene expression levels with PD-L1 IHC scores generated using the VENTANA PD-L1 (SP142) Assay. The PD-L1 IHC assessment was carried out double blinded by an independent laboratory. PD-L1 IHC scores were calculated using an algorithm combining tumour proportion score (TPS) with a PD-L1 positive immune cell (IC) score and immune cell area. Results: An exceptionally high degree of correlation was observed between the NGS PD-L1 levels with the combined PD-L1 IHC scores (P < 0.001). Therapeutic cut points for NGS PD-L1 levels were identified corresponding to PD-L1 IHC defined clinical cut points. Notably, ~20% of patients with negative PD-L1 IHC scores showed high NGS PD-L1 expression levels. We hypothesize that these cases represent false negatives and identify a cohort of patients who have shown significant response rates to anti-PD-L1/PD-directed immunotherapies. Conclusions: The Immunofocus NGS PD-L1 assay has potential to greatly improve patient selection for immunotherapy by removing the IHC assay variables and inter-reader variability which compromise current PD-L1 IHC tests while also providing standardized high throughput in the clinical setting. Immunofocus is able to integrate gene expression with somatic mutation analysis allowing capture of networks regulating the immune-checkpoint including for example adaptive and innate resistance pathways, JAK1/2 pathways, differential MHC expression, TEFF gene signature, neoantigen surrogates such as DDR defects and TMB. The integration of NGS PD-L1 expression with other putative biomarkers of response is presently ongoing to further improve prediction of response.

A clinical case of Wilson — Konovalov disease in the practice of gastroenterologist

Wilson — Konovalov disease (in the English literature known as Wilson’s disease) is a rare inherited disease with autosomal recessive type of inheritance, which is based on a genetic defect in copper metabolism. Since copper is a part of almost all foods and plays a role of coenzyme in many processes in the body, this element cannot be excluded from the diet. For individuals with absence of excretion of copper ions from the cell, a violation of the fatty acid structure of the cell membrane is inevitable. As a result, its integrity is lost, which leads to degeneration of organs and tissues. Symptoms may include psychiatric (depression, apathy) and neurological disorders (gait disturbance, tremor, irritability), idiopathic hepatitis and cirrhosis, hemolytic anemia, disorders of the cardiovascular and musculoskeletal systems. The insidiousness of this disease is that copper can accumulate for years and not cause severe symptoms until it reaches a certain threshold level, and then in a very short time causes irreversible changes in the body. This threshold level is individual for everyone. It is clinically confirmed that the signs of liver damage are ahead of neurological manifestations by 10 years. Liver damage has been reported in all patients with neurological manifestations. Another important manifestation of the disease is the formation of the Kaiser‑Fleischer ring due to the accumulation of copper in the descemet’s membrane of the cornea. It is found in 95 % of people with neurological manifestations, but is practically not found in children with the disease. An important criterion for diagnosis is psychiatric and behavioural changes, which often precede hepatic manifestations, but are written off at puberty. Such a wide range of disorders is stipulated by the fact that copper is a cofactor of many enzymes in the body. Predictive testing and timely administration of specific treatment will help to avoid such processes. Untreated disease progresses with the development of acute liver failure with the subsequent need for liver transplantation.The authors give an overview of recent data on the etiology, pathogenesis, clinical manifestations, methods of treatment of Wilson — Konovalov disease, and present their own clinical observation of a complex case of Wilson — Konovalov disease in a young girl of 20 years old.

Predictive molecular pathology in the time of COVID-19

AimsIn the time of COVID-19, predictive molecular pathology laboratories must still timely select oncological patients for targeted treatments. However, the need to respect social distancing measures may delay results generated...

Clinical impact of post-mortem genetic testing in cardiac death and cardiomyopathy.

Post-mortem genetic analyses may help to elucidate the cause of cardiac death. The added value is however unclear when a cardiac disease is already suspected or affirmed. Our aim was to study the feasibility and medical impact of post-mortem genetic analyses in suspected cardiomyopathy. We studied 35 patients with cardiac death and suspected cardiomyopathy based on autopsy or clinical data. After targeted sequencing, we identified 15 causal variants in 15 patients (yield 43%) in sarcomeric (n = 8), desmosomal (n = 3), lamin A/C (n = 3) and transthyretin (n = 1) genes. The results had various impacts on families, i.e. allowed predictive genetic testing in relatives (15 families), planned early therapeutics based on the specific underlying gene (5 families), rectified the suspected cardiomyopathy subtype (2 families), assessed the genetic origin of cardiomyopathy that usually has an acquired cause (1 family), assessed the diagnosis in a patient with uncertain borderline cardiomyopathy (1 family), reassured the siblings because of a de novo mutation (2 families) and allowed prenatal testing (1 family). Our findings suggest that post-mortem molecular testing should be included in the strategy of family care after cardiac death and suspected cardiomyopathy, since genetic findings provide additional information useful for relatives, which are beyond conventional autopsy.

Predictive genetic testing in Huntington's disease: should a neurologist be involved?

International guidelines on Huntington’s Disease recommend neurological examination in the predictive testing trajectory. Experiences and personal wishes of persons at risk of Huntington’s Disease regarding this topic have never been evaluated. The objective was to provide an overview of the experiences of Dutch at-risk persons, opting for predictive testing, in consulting a neurologist before and after DNA analysis. Persons who were counseled in four Dutch clinics between 2017 and 2019 were retrospectively or prospectively approached for a questionnaire which listed topics as experiences with consultation and personal wishes. From 71 participants, 44 participants visited a neurologist. 41 participants indicated their visit to a neurologist as positive (93.2%). The majority of participants (n = 59) desired consulting a neurologist. Thirty-two participants indicated consultation shortly after (Desired After Group) and twenty-seven before DNA analysis (Desired Before Group) as personal wish. The Desired Before Group consisted of a significantly higher number of participants who actually consulted a neurologist before predictive testing (n = 26) compared with the number of participants who actually consulted a neurologist after DNA analysis in the Desired After Group (n = 11) (p < 0.001). The Desired After Group (n = 19) had a significantly higher number of Huntington’s disease gene expansion carriers compared with the Desired Before Group (n = 5) (p 0.003). Participants are content with consultation. However, persons without the gene expansion still feel the need to get in touch with a neurologist. Therefore, offering a consultation with a neurologist before DNA analysis might be beneficial for all.

Comparison of Circulating Cell-Free DNA Extraction Methods for Downstream Analysis in Cancer Patients.

Circulating cell-free DNA (ccfDNA) may contain DNA originating from the tumor in plasma of cancer patients (ctDNA) and enables noninvasive cancer diagnosis, treatment predictive testing, and response monitoring. A recent multicenter evaluation of workflows by the CANCER-ID consortium using artificial spiked-in plasma showed significant differences and consequently the importance of carefully selecting ccfDNA extraction methods. Here, the quantity and integrity of extracted ccfDNA from the plasma of cancer patients were assessed. Twenty-one cancer patient-derived cell-free plasma samples were selected to compare the Qiagen CNA, Maxwell RSC ccfDNA plasma, and Zymo manual quick ccfDNA kit. High-volume citrate plasma samples collected by diagnostic leukapheresis from six cancer patients were used to compare the Qiagen CNA (2 mL) and QIAamp MinElute ccfDNA kit (8 mL). This study revealed similar integrity and similar levels of amplified short-sized fragments and tumor-specific mutants comparing the CNA and RSC kits. However, the CNA kit consistently showed the highest yield of ccfDNA and short-sized fragments, while the RSC and ME kits showed higher variant allelic frequencies (VAFs). Our study pinpoints the importance of standardizing preanalytical conditions as well as consensus on defining the input of ccfDNA to accurately detect ctDNA and be able to compare results in a clinical routine practice, within and between clinical studies.

Addressing ethical challenges of disclosure in dementia prediction: limitations of current guidelines and suggestions to proceed

BackgroundBiomarker research is gaining increasing attention focusing on the preclinical stages of the disease. Such interest requires special attention for communication and disclosure in clinical contexts. Many countries give dementia a high health policy priority by developing national strategies and by improving guidelines addressing disclosure of a diagnosis; however, risk communication is often neglected.Main textThis paper aims to identify the challenges of disclosure in the context of dementia prediction and to find out whether existing clinical guidelines sufficiently address the issues of disclosing a dementia diagnosis and of disclosing the risk of developing dementia in asymptomatic and MCI stage. We will examine clinical guidelines and recommendations of three countries (USA, Canada and Germany) regarding predictive testing and diagnostic disclosure in dementia and Mild Cognitive Impairment (MCI) to show their potentials and limits. This will provide a background to address ethical implications of predictive information and to identify ways how to proceed further. We will start by examining the guidelines and recommendations by focusing on what there is already and what is missing regarding the challenges of disclosing dementia prediction and MCI. Then, we will highlight the novel ethical issues generated by the shift to identify preclinical stages of the disease by biomarkers. We will argue for the need to develop guidelines for disclosing a risk status, which requires different considerations then disclosing a diagnosis of dementia. Finally, we will make some suggestions on how to address the gap and challenges raised by referring to German Stakeholder Conference, which presents us a good starting point to the applicability of involving stakeholders.ConclusionsThis paper underlines the need to develop empirically based guidelines that address the ethical and social strategies for risk communication of dementia prediction by genetic as well as non-genetic biomarkers. According to our analysis, the guidelines do not address the new developments sufficiently. International efforts should aim for specific guidelines on counseling, communicating risk and disclosing results. We argue that guidelines on (risk) disclosure should be developed by involving various stakeholders and should be informed by socio-empirical studies involving laypersons’ needs and wishes regarding risk communication.

Psychosocial Impact of Predictive Genetic Testing in Hereditary Heart Diseases: The PREDICT Study

Predictive genetic testing (PGT) is offered to asymptomatic relatives at risk of hereditary heart disease, but the impact of result disclosure has been little studied. We evaluated the psychosocial impacts of PGT in hereditary heart disease, using self-report questionnaires (including the State-Trait Anxiety Inventory) in 517 adults, administered three times to the prospective cohort (PCo: n = 264) and once to the retrospective cohort (RCo: n = 253). The main motivations for undergoing PGT were “to remove doubt” and “for their children”. The level of anxiety increased between pre-test and result appointments (p <0.0001), returned to baseline after the result (PCo), and was moderately elevated at 4.4 years (RCo). Subjects with a history of depression or with high baseline anxiety were more likely to develop anxiety after PGT result (p = 0.004 and p <0.0001, respectively), whatever it was. Unfavourable changes in professional and/or family life were observed in 12.4% (PCo) and 18.7% (RCo) of subjects. Few regrets about PGT were expressed (0.8% RCo, 2.3% PCo). Medical benefit was not the main motivation, which emphasises the role of pre/post-test counselling. When PGT was performed by expert teams, the negative impact was modest, but careful management is required in specific categories of subjects, whatever the genetic test result.