Screening Asymptomatic People Research Articles

ESMO recommendations on the use of circulating tumour DNA assays for patients with cancer: a report from the ESMO Precision Medicine Working Group

Circulating tumour DNA (ctDNA) assays conducted on plasma are rapidly developing a strong evidence base for use in patients with cancer. The European Society for Medical Oncology convened an expert working group to review the analytical and clinical validity and utility of ctDNA assays. For patients with advanced cancer, validated and adequately sensitive ctDNA assays have utility in identifying actionable mutations to direct targeted therapy, and may be used in routine clinical practice, provided the limitations of the assays are taken into account. Tissue-based testing remains the preferred test for many cancer patients, due to limitations of ctDNA assays detecting fusion events and copy number changes, although ctDNA assays may be routinely used when faster results will be clinically important, or when tissue biopsies are not possible or inappropriate. Reflex tumour testing should be considered following a non-informative ctDNA result, due to false-negative results with ctDNA testing. In patients treated for early-stage cancers, detection of molecular residual disease or molecular relapse, has high evidence of clinical validity in anticipating future relapse in many cancers. Molecular residual disease/molecular relapse detection cannot be recommended in routine clinical practice, as currently there is no evidence for clinical utility in directing treatment. Additional potential applications of ctDNA assays, under research development and not recommended for routine practice, include identifying patients not responding to therapy with early dynamic changes in ctDNA levels, monitoring therapy for the development of resistance mutations before clinical progression, and in screening asymptomatic people for cancer. Recommendations for reporting of results, future development of ctDNA assays and future clinical research are made.

Serum or plasma ferritin concentration as an index of iron deficiency and overload.

Serum or plasma ferritin concentration as an index of iron deficiency and overload.

Challenges in Laboratory Diagnosis of the Novel Coronavirus SARS-CoV-2.

The recent outbreak of the Coronavirus disease 2019 (COVID-19) has quickly spread worldwide since its discovery in Wuhan city, China in December 2019. A comprehensive strategy, including surveillance, diagnostics, research, clinical treatment, and development of vaccines, is urgently needed to win the battle against COVID-19. The past three unprecedented outbreaks of emerging human coronavirus infections at the beginning of the 21st century have highlighted the importance of readily available, accurate, and rapid diagnostic technologies to contain emerging and re-emerging pandemics. Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) based assays performed on respiratory specimens remain the gold standard for COVID-19 diagnostics. However, point-of-care technologies and serologic immunoassays are rapidly emerging with high sensitivity and specificity as well. Even though excellent techniques are available for the diagnosis of symptomatic patients with COVID-19 in well-equipped laboratories; critical gaps still remain in screening asymptomatic people who are in the incubation phase of the virus, as well as in the accurate determination of live viral shedding during convalescence to inform decisions for ending isolation. This review article aims to discuss the currently available laboratory methods and surveillance technologies available for the detection of COVID-19, their performance characteristics and highlight the gaps in current diagnostic capacity, and finally, propose potential solutions. We also summarize the specifications of the majority of the available commercial kits (PCR, EIA, and POC) for laboratory diagnosis of COVID-19.

ECG-based cardiac screening programs: Legal, ethical, and logistical considerations

Screening asymptomatic people with a resting electrocardiogram (ECG) has been theorized to detect latent cardiovascular disease. However, resting ECG screening is not recommended for numerous populations, such as asymptomatic middle-aged (sedentary) people, as it is not sufficiently sensitive to detect coronary artery disease. While the issues raised in this article are largely common to all screening programs, this review focuses on 2 distinct programs: (1) screening elite athletes for conditions associated with sudden cardiac death (SCD); and (2) screening people aged ≥65 years for atrial fibrillation (AF). These 2 settings have recently gained attention for their promise and concerns regarding prevention of SCD and stroke, respectively. If screening is to be done, it must be done well. Organizations conducting screening must consider a range of legal, ethical, and logistical responsibilities that arise from the beginning to the end of the process. This includes consideration of who to screen, timing of screening, whether screening is mandatory, consent issues, and auditing systems to ensure quality control. Good infrastructure for interpretation of ECG results according to expert guidelines and follow-up testing for abnormal screening results, including a pathway to treatment, are essential. Finally, there may be significant implications for those diagnosed with cardiac disease, including insurance, employment, the ability to play sport, and mental health issues. There are several legal risks, and the best protective measures are good communication systems, thorough clinical record-keeping, careful handling of eligibility questions for those diagnosed, and reference to expert guidelines as the standard of care.

Screening with urinary dipsticks for reducing morbidity and mortality.

Urinary dipsticks are sometimes used for screening asymptomatic people, and for case-finding among inpatients or outpatients who do not have genitourinary symptoms. Abnormalities identified on screening sometimes lead to additional investigations, which may identify serious disease, such as bladder cancer and chronic kidney disease (CKD). Urinary dipstick screening could improve prognoses due to earlier detection, but could also lead to unnecessary and potentially invasive follow-up testing and unnecessary treatment. We aimed to quantify the benefits and harms of screening with urinary dipsticks in general populations and patients in hospitals. We searched the Cochrane Renal Group's Specialised Register to 8 September 2014 through contact with the Trials Search Co-ordinator using search terms relevant to this review. Randomised controlled trials and other study types that compared urinary dipstick screening with no dipstick screening were eligible for inclusion. We searched for studies that investigated the use of urinary dipsticks for detecting haemoglobin, protein, albumin, albumin-creatinine ratio, leukocytes, nitrite, or glucose, alone or in any combination, and in any setting. We planned to exclude studies conducted in patients with urinary disorders. It was planned that two authors would independently extract data from included studies and assess risk of bias using the Cochrane risk of bias tool. However, no studies met our inclusion criteria. Literature searches to 8 September 2014 yielded 4298 records, of which 4249 were excluded following title and abstract assessment. There were 49 records (44 studies) eligible for full text assessment; of these 18 studies were not RCTs and 26 studies compared interventions or controls that were not relevant to this review. Thus, no studies were eligible for inclusion. We found no evidence to assess the benefits and harms of screening with urinary dipsticks, which remain unknown.

Screening Colonoscopy for Colorectal Cancer in Asymptomatic People: A Meta-Analysis

The preferred method for screening asymptomatic people for colorectal cancer (CRC) is colonoscopy, according to the new American guidelines. The aim of our study was to perform a meta-analysis of the prospective cohorts using total colonoscopy for screening this population for CRC. We looked for the diagnostic yield of the procedure as well as for its safety in a screening setting. We included papers with more than 500 participants and only those reporting diagnostic yield of adenoma (and/or advanced adenoma) and CRC. Nested analysis were performed for secondary endpoints of complications and CRC stages when this information was available. All analyses were performed with StatDirect Statistical software, version 2.6.1 ( http://www.statsdirect.com ). Our search yielded ten studies of screening colonoscopy conducted in asymptomatic people that met our inclusion criteria, with a total of 68,324 participants. Colonoscopy was complete and reached the cecum in 97% of the procedures. Colorectal cancer was found in 0.78% of the participants (95% confidence interval 0.13-2.97%). Stage I or II were found in 77% of the patients with CRC. Advanced adenoma was found in 5% of the cases (95% confidence interval 4-6%). Complications were rare and described in five cohorts. Perforation developed in 0.01% of the cases (95% confidence interval 0.006-0.02%) and bleeding in 0.05% (95% confidence interval 0.02-0.09%). Our findings support the notion that colonoscopy is feasible and a suitable method for screening for CRC in asymptomatic people.

Computed tomographic colonography: clinical value

Computed tomographic colonography (CTC) has the potential to reliably detect polyps in the colon. Its clinical value is accepted for several indications. The main target is screening asymptomatic people for colorectal cancer (CRC). As in large multi-centre trials controversial results were obtained, acceptance of this indication on a large scale is still pending. Agreement exists that in experienced hands screening can be performed with CTC. This emphasizes the importance of adequate and intensive training. Besides this, other problems have to be solved. A low complication profile is mandatory. Perforation rate is very low. Ultra-low dose radiation should be used. When screening large patient cohorts, CTC will need a time-efficient and cost-effective management without too many false positives and additional exploration. Can therefore a cut-off size of polyp detection safely be installed? Is the flat lesion an issue? Can extra-colonic findings be treated efficiently? A positive relationship with the gastro-enterologists will improve the act of screening. Improvements of scanning technique and software with dose reduction, improved 3D visualisation methods and CAD are steps in the good direction. Finally, optimisation of laxative-free CTC could be invaluable in the development of CTC as a screening tool for CRC.

Should We Screen for Occupational Lung Cancer With Low-Dose Computed Tomography?

The objective of this study was to assess the potential value of screening for occupational lung cancer through the use of low-dose computed tomography (LDCT). A literature review of Medline was conducted to assess: 1) screening studies of occupational lung cancer that used LDCT; 2) screening studies of nonoccupational lung cancer that used LDCT; and 3) position papers of medical professional societies and nongovernmental health organizations that have addressed the value of screening for lung cancer with LDCT. No screening studies of occupational lung cancer with LDCT were uncovered; however, numerous observational and population-based studies have addressed the value of screening for lung cancer among cigarette smokers. Results of these studies are difficult to interpret in light of numerous biases associated with these types of studies. No randomized, controlled studies on screening for lung cancer have been published at this time. No professional, governmental, or nonprofit health organization recommends screening asymptomatic people at risk of lung cancer with LDCT at this time. In the absence of randomized, controlled studies that can address biases commonly encountered in observational and population-based studies, it is unclear whether LDCT reduces mortality from lung cancer. The National Cancer Institute is sponsoring a randomized, controlled study of over 50,000 current and former smokers with the results expected in 2009.

Systematic review: the use of serology to exclude or diagnose coeliac disease (a comparison of the endomysial and tissue transglutaminase antibody tests)

With the appreciation of the high prevalence of coeliac disease there is increasing use of serology in screening asymptomatic people and testing those with suggestive features. To compare the sensitivities and specificities of the endomysial antibody and the tissue transglutaminase antibody tests. Using electronic databases a search was made for relevant papers using the terms tissue transglutaminase and endomysial antibody. Both the endomysial antibody and tissue transglutaminase antibody have very high sensitivities (93% for both) and specificities (>99% and >98% respectively) for the diagnosis of typical coeliac disease with villous atrophy. Human recombinant tissue transglutaminase performs much better than guinea pig tissue transglutaminase. Review of studies comparing endomysial antibody with human recombinant tissue transglutaminase antibody shows that endomysial antibody more often has a higher specificity and human recombinant tissue transglutaminase antibody more often has a higher sensitivity. The human recombinant tissue transglutaminase antibody is the preferred test for screening asymptomatic people and for excluding coeliac disease in symptomatic individuals with a low pretest probability (i.e. <25%) for coeliac disease. Furthermore, it has a number of practical and financial advantages. If the pretest probability is >25%, biopsy is preferred as the post-test probability of coeliac disease with a negative test is still >2%.

Screening for type 2 diabetes mellitus to prevent vascular complications: updated recommendations from the Canadian Task Force on Preventive Health Care

In developing these recommendations, the Canadian Task Force on Preventive Health Care drew heavily on a recent systematic review prepared for the US Preventive Services Task Force of the evidence for screening asymptomatic people for type 2 diabetes mellitus to prevent cardiovascular events.[1][1]

Screening asymptomatic people at high risk for hepatitis C. The case against.

The hepatitis C virus is usually transmitted parenterally through blood products or shared needles. Most infected people develop mild chronic hepatitis, which tends to pursue an asymptomatic course over years or decades.1 It is not known how many of those affected will eventually develop clinical sequelae from liver disease. Screening blood donations for antibodies to the hepatitis C virus has led to a considerable reduction in the incidence of transfusion associated hepatitis.2 The United Kingdom's National Blood Transfusion Service has introduced a hepatitis C “lookback” programme to identify and screen those known to have received infected blood before testing of donations began in 1991. Other individuals at risk include injecting drug users, people with haemophilia, and health care workers. According to one estimate there may be 200 000 people with chronic hepatitis C in the United Kingdom.3 Should asymptomatic individuals belonging to these groups be offered screening for hepatitis C? This question raises both medical and ethical issues which share an analogy with screening for infection with HIV. A positive test result for hepatitis C comes as a devastating blow to a healthy person. Concerns are raised about the mode of viral acquisition, risk of transmission to close contacts, marriage, employment and life insurance prospects, and the future risk of cirrhosis and hepatoma. …

Screening asymptomatic people at high risk for hepatitis C. The case for.

In some respects hepatitis C is hepatitis B revisited. Years after the discovery of hepatitis B virus and 11 years after development of a safe, efficacious vaccine, consensus has emerged in the international health community that decisive global action against hepatitis B is a necessity.1 Those who doubt that a similar approach will be needed towards hepatitis C point to a relative lack of knowledge of the clinical course of hepatitis C and the efficacy of treatment. In 1989 hepatitis C virus was cloned and characterised as a positive sense, single stranded RNA genome containing 9400 nucleotides. It is a major cause of post-transfusion hepatitis2; up to 50% of patients commonly progress to chronic hepatitis and 20% to cirrhosis with secondary complications such as hepatocellular carcinoma.3 A problem arises because hepatitis C may have a progressive course to chronic disease occurring over decades, during which time the individual may be symptom free and the disease remain undiagnosed until the patient presents with liver disease or its complications.2 3 In the United States 3.5 million people are estimated to have chronic hepatitis C; of these, 8000-10000 die of liver related complications and 1000 undergo liver transplantation.4 Around 23% of patients given a transplant had hepatitis C virus, and 19% of those given transplants for seronegative cryptogenic cirrhosis developed hepatitis C after transplantation.4 5 Prevalence is similar in Europe and higher in Japan and other eastern countries. The hepatitis C virus is transmitted parenterally through blood, blood products, injecting drug misuse, and tattooing, as well as by sexual6 and household transmission. Serological identification of hepatitis C virus by second and …