Correction: External validation of risk prediction models for incident colorectal cancer using UK Biobank.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Binding affinity data of DNA aptamers for therapeutic anthracyclines from microscale thermophoresis and surface plasmon resonance spectroscopy.

Anthracyclines like daunorubicin (DRN) and doxorubicin (DOX) play an undisputed key role in cancer treatment, but their chronic administration can cause severe side effects. For precise anthracycline analytical systems, aptamers are preferable recognition elements. Here, we describe the detailed characterisation of a single-stranded DNA aptamer DRN-10 and its truncated versions for DOX and DRN detection. Binding affinities were determined from surface plasmon resonance (SPR) and microscale thermophoresis (MST) and combined with conformational data from circular dichroism (CD). Both aptamers displayed similar nanomolar binding affinities to DRN and DOX, even though their rate constants differed as shown by SPR recordings. SPR kinetic data unravelled a two-state reaction model including a 1 : 1 binding and a subsequent conformational change of the binding complex. This model was supported by CD spectra. In addition, the dissociation constants determined with MST were always lower than that from SPR, and especially for the truncated aptamer they differed by two orders of magnitude. This most probably reflects the methodological difference, namely labelling for MST vs. immobilisation for SPR. From CD recordings, we suggested a specific G-quadruplex as structural basis for anthracycline binding. We concluded that the aptamer DRN-10 is a promising recognition element for anthracycline detection systems and further selected aptamers can be also characterised with the combined methodological approach presented here.

Dermoscopy use in UK primary care: a survey of GPs with a special interest in dermatology.

BACKGROUND: Melanoma accounts for 90% of skin cancer mortality and typically presents in primary care, where it can be challenging to distinguish from benign lesions. Dermoscopy is a tool for skin visualization that is routinely used for melanoma diagnosis in secondary care. However, the role of dermoscopy in primary care remains unclear. OBJECTIVES: To determine views on, and use of, dermoscopy by dermatology-interested general practitioners (GPs). METHODS: An online questionnaire was emailed to the UK Primary Care Dermatology Society members in February 2018, and responses collected over the following 4 weeks. RESULTS: A total of 205 responses were analysed. Most respondents were GPs (94%), aged over 50 (53%), had a postgraduate dermatological qualification (67%) and used dermoscopy regularly when reviewing pigmented skin lesions (97%). Dermoscopy use was commoner amongst GPs who had worked longer in primary care and had experience of secondary care dermatology. Most had undertaken training in dermoscopy (91%), although one-fifth (20%) had not updated their training in over 5 years. Most of those who had received only 1 day of face-to-face training reported feeling confident using a dermatoscope. Few respondents (11%) reported access to teledermatology or teledermoscopy for urgent or routine referrals. CONCLUSIONS: UK GPs with a special interest in dermatology are routinely using dermoscopy in the primary care setting. More research is needed to establish optimal approaches to training and updating GP dermoscopy skills. When dermoscopy has been shown to be safe, effective, acceptable and cost-effective in this setting, more GPs may also be able to gain and maintain the skills to implement dermoscopy into routine primary care. Technological advances, including incorporation of artificial intelligence (AI) and algorithms to guide GPs, could also contribute to widening use of dermoscopy among GPs.

External validation of risk prediction models for incident colorectal cancer using UK Biobank.

BACKGROUND: This study aimed to compare and externally validate risk scores developed to predict incident colorectal cancer (CRC) that include variables routinely available or easily obtainable via self-completed questionnaire. METHODS: External validation of fourteen risk models from a previous systematic review in 373 112 men and women within the UK Biobank cohort with 5-year follow-up, no prior history of CRC and data for incidence of CRC through linkage to national cancer registries. RESULTS: There were 1719 (0.46%) cases of incident CRC. The performance of the risk models varied substantially. In men, the QCancer10 model and models by Tao, Driver and Ma all had an area under the receiver operating characteristic curve (AUC) between 0.67 and 0.70. Discrimination was lower in women: the QCancer10, Wells, Tao, Guesmi and Ma models were the best performing with AUCs between 0.63 and 0.66. Assessment of calibration was possible for six models in men and women. All would require country-specific recalibration if estimates of absolute risks were to be given to individuals. CONCLUSIONS: Several risk models based on easily obtainable data have relatively good discrimination in a UK population. Modelling studies are now required to estimate the potential health benefits and cost-effectiveness of implementing stratified risk-based CRC screening.

Variation in 'fast-track' referrals for suspected cancer by patient characteristic and cancer diagnosis: evidence from 670 000 patients with cancers of 35 different sites.

BACKGROUND: In England, 'fast-track' (also known as 'two-week wait') general practitioner referrals for suspected cancer in symptomatic patients are used to shorten diagnostic intervals and are supported by clinical guidelines. However, the use of the fast-track pathway may vary for different patient groups. METHODS: We examined data from 669 220 patients with 35 cancers diagnosed in 2006-2010 following either fast-track or 'routine' primary-to-secondary care referrals using 'Routes to Diagnosis' data. We estimated the proportion of fast-track referrals by sociodemographic characteristic and cancer site and used logistic regression to estimate respective crude and adjusted odds ratios. We additionally explored whether sociodemographic associations varied by cancer. RESULTS: There were large variations in the odds of fast-track referral by cancer (P<0.001). Patients with testicular and breast cancer were most likely to have been diagnosed after a fast-track referral (adjusted odds ratios 2.73 and 2.35, respectively, using rectal cancer as reference); whereas patients with brain cancer and leukaemias least likely (adjusted odds ratios 0.05 and 0.09, respectively, for brain cancer and acute myeloid leukaemia). There were sex, age and deprivation differences in the odds of fast-track referral (P<0.013) that varied in their size and direction for patients with different cancers (P<0.001). For example, fast-track referrals were least likely in younger women with endometrial cancer and in older men with testicular cancer. CONCLUSIONS: Fast-track referrals are less likely for cancers characterised by nonspecific presenting symptoms and patients belonging to low cancer incidence demographic groups. Interventions beyond clinical guidelines for 'alarm' symptoms are needed to improve diagnostic timeliness.

Factors associated with intentional and unintentional non-adherence to adjuvant endocrine therapy following breast cancer.

Adherence to adjuvant endocrine therapy (AET) following breast cancer is known to be suboptimal despite its known efficacy in reducing recurrence and mortality. This study aims to investigate factors associated with non-adherence and inform the development of interventions to support women and promote adherence. A questionnaire survey to measure level of adherence, side effects experienced, beliefs about medicine, support received and socio-demographic details was sent to 292 women 2-4 years post breast cancer diagnosis. Differences between non-adherers and adherers to AET were explored, and factors associated with intentional and unintentional non-adherence are reported. Approximately one quarter of respondents, 46 (22%), were non-adherers, comprising 29 (14%) intentional non-adherers and 17 (8%) unintentional non-adherers. Factors significantly associated with intentional non-adherence were the presence of side effects (p < .03), greater concerns about AET (p < .001) and a lower perceived necessity to take AET (p < .001). Half of the sample (105/211) reported that side effects had a moderate or high impact on their quality of life. Factors associated with unintentional non-adherence were younger age (<65) (p < .001), post-secondary education (p = .046) and paid employment (p = .031). There are distinct differences between intentional non-adherence and unintentional non-adherence. Differentiation between the two types of non-adherence may help tailor support and advice interventions.

Identifying people at higher risk of melanoma across the U.K.: a primary-care-based electronic survey.

BACKGROUND: Melanoma incidence is rising rapidly worldwide among white populations. Defining higher-risk populations using risk prediction models may help targeted screening and early detection approaches. OBJECTIVES: To assess the feasibility of identifying people at higher risk of melanoma using the Williams self-assessed clinical risk estimation model in U.K. primary care. METHODS: We recruited participants from the waiting rooms of 22 general practices covering a total population of > 240 000 in three U.K. regions: Eastern England, North East Scotland and North Wales. Participants completed an electronic questionnaire using tablet computers. The main outcome was the mean melanoma risk score using the Williams melanoma risk model. RESULTS: Of 9004 people approached, 7742 (86%) completed the electronic questionnaire. The mean melanoma risk score for the 7566 eligible participants was 17·15 ± 8·51, with small regional differences [lower in England compared with Scotland (P = 0·001) and Wales (P < 0·001), mainly due to greater freckling and childhood sunburn among Scottish and Welsh participants]. After weighting to the age and sex distribution, different potential cut-offs would allow between 4% and 20% of the population to be identified as higher risk, and those groups would contain 30% and 60%, respectively of those likely to develop melanoma. CONCLUSIONS: Collecting data on the melanoma risk profile of the general population in U.K. primary care is both feasible and acceptable for patients in a general practice setting, and provides opportunities for new methods of real-time risk assessment and risk stratified cancer interventions.

Implementing a QCancer risk tool into general practice consultations: an exploratory study using simulated consultations with Australian general practitioners.

BACKGROUND: Reducing diagnostic delays in primary care by improving the assessment of symptoms associated with cancer could have significant impacts on cancer outcomes. Symptom risk assessment tools could improve the diagnostic assessment of patients with symptoms suggestive of cancer in primary care. We aimed to explore the use of a cancer risk tool, which implements the QCancer model, in consultations and its potential impact on clinical decision making. METHODS: We implemented an exploratory 'action design' method with 15 general practitioners (GPs) from Victoria, Australia. General practitioners applied the risk tool in simulated consultations, conducted semi-structured interviews based on the normalisation process theory and explored issues relating to implementation of the tool. RESULTS: The risk tool was perceived as being potentially useful for patients with complex histories. More experienced GPs were distrustful of the risk output, especially when it conflicted with their clinical judgement. Variable interpretation of symptoms meant that there was significant variation in risk assessment. When a risk output was high, GPs were confronted with numerical risk outputs creating challenges in consultation. CONCLUSIONS: Significant barriers to implementing electronic cancer risk assessment tools in consultation could limit their uptake. These relate not only to the design and integration of the tool but also to variation in interpretation of clinical histories, and therefore variable risk outputs and strong beliefs in personal clinical intuition.

Symptoms and other factors associated with time to diagnosis and stage of lung cancer: a prospective cohort study.

BACKGROUND: This prospective cohort study aimed to identify symptom and patient factors that influence time to lung cancer diagnosis and stage at diagnosis. METHODS: Data relating to symptoms were collected from patients upon referral with symptoms suspicious of lung cancer in two English regions; we also examined primary care and hospital records for diagnostic routes and diagnoses. Descriptive and regression analyses were used to investigate associations between symptoms and patient factors with diagnostic intervals and stage. RESULTS: Among 963 participants, 15.9% were diagnosed with primary lung cancer, 5.9% with other thoracic malignancies and 78.2% with non-malignant conditions. Only half the cohort had an isolated first symptom (475, 49.3%); synchronous first symptoms were common. Haemoptysis, reported by 21.6% of cases, was the only initial symptom associated with cancer. Diagnostic intervals were shorter for cancer than non-cancer diagnoses (91 vs 124 days, P=0.037) and for late-stage than early-stage cancer (106 vs 168 days, P=0.02). Chest/shoulder pain was the only first symptom with a shorter diagnostic interval for cancer compared with non-cancer diagnoses (P=0.003). CONCLUSIONS: Haemoptysis is the strongest symptom predictor of lung cancer but occurs in only a fifth of patients. Programmes for expediting earlier diagnosis need to focus on multiple symptoms and their evolution.

Smartphone applications for melanoma detection by community, patient and generalist clinician users: a review.

Smartphone health applications ('apps') are widely available but experts remain cautious about their utility and safety. We reviewed currently available apps for the detection of melanoma (July 2014), aimed at general community, patient and generalist clinician users. A proforma was used to extract and assess each app that met the inclusion criteria, and we undertook content analysis to evaluate their content and the evidence applied in their development. Thirty-nine apps were identified with the majority available only for Apple users. Over half (n = 22) provided information or education about melanoma, ultraviolet radiation exposure prevention advice, and skin self-examination strategies, mainly using the ABCDE (A, Asymmetry; B, Border; C, Colour; D, Diameter; E, Evolving) method. Half (n = 19) helped users take and store images of their skin lesions either for review by a dermatologist or for self-monitoring to identify change, an important predictor of melanoma; a similar number (n = 18) used reminders to help users monitor their skin lesions. A few (n = 9) offered expert review of images. Four apps provided a risk assessment to patients about the probability that a lesion was malignant or benign, and one app calculated users' future risk of melanoma. None of the apps appeared to have been validated for diagnostic accuracy or utility using established research methods. Smartphone apps for detecting melanoma by nonspecialist users have a range of functions including information, education, classification, risk assessment and monitoring change. Despite their potential usefulness, and while clinicians may choose to use apps that provide information to educate their patients, apps for melanoma detection require further validation of their utility and safety.

Bright or dark immune complexes of anti-TAMRA antibodies for adapted fluorescence-based bioanalysis.

Fluorescence labels, for example fluorescein or rhodamin derivatives, are widely used in bioanalysis applications including lateral-flow assays, PCR, and fluorescence microscopy. Depending on the layout of the particular application, fluorescence quenching or enhancement may be desired as the detection principle. Especially for multiplexed applications or high-brightness requirements, a tunable fluorescence probe can be beneficial. The alterations in the photophysics of rhodamine derivatives upon binding to two different anti-TAMRA antibodies were investigated by absorption and fluorescence-spectroscopy techniques, especially determining the fluorescence decay time and steady-state and time-resolved fluorescence anisotropy. Two monoclonal anti-TAMRA antibodies were generated by the hybridoma technique. Although surface-plasmon-resonance measurements clearly proved the high affinity of both antibodies towards 5-TAMRA, the observed effects on the fluorescence of rhodamine derivatives were very different. Depending on the anti-TAMRA antibody either a strong fluorescence quenching (G71-DC7) or a distinct fluorescence enhancement (G71-BE11) upon formation of the immune complex was observed. Additional rhodamine derivatives were used to gain further information on the binding interaction. The data reveal that such haptens as 5-TAMRA could generate different paratopes with equal binding affinities but different binding interactions, which provide the opportunity to adapt bioanalysis methods including immunoassays for optimized detection principles for the same hapten depending on the specific requirements.

Characterization of a new maleimido functionalization of gold for surface plasmon resonance spectroscopy.

Para-maleimidophenyl (p-MP) modified gold surfaces have been prepared by one-step electrochemical deposition and used in surface plasmon resonance (SPR) studies. Therefore, a FITC mimotope peptide (MP1, 12 aa), a human mucin 1 epitope peptide (MUC, 9 aa) and a protein with their specific antibodies were used as model systems. The peptides were modified with an N-terminal cysteine for covalent and directed coupling to the maleimido functionalized surface by means of Michael addition. The coupling yield of the peptide, the binding characteristics of antibody and the unspecific adsorption of the analytes were investigated. The results expand the spectrum of biosensors usable with p-MP by widely used SPR and support its potential to be versatile for several electrochemical and optical biosensors. This allows the combination of an electrochemical and optical read-out for a broad variety of biomolecular interactions on the same chip.

The risk of oesophago-gastric cancer in symptomatic patients in primary care: a large case-control study using electronic records.

BACKGROUND: Over 15 000 new oesophago-gastric cancers are diagnosed annually in the United Kingdom, with most being advanced disease. We identified and quantified features of this cancer in primary care. METHODS: Case-control study using electronic primary-care records of the UK patients aged ≥40 years was performed. Cases with primary oesophago-gastric cancer were matched to controls on age, sex and practice. Putative features of cancer were identified in the year before diagnosis. Odds ratios (ORs) were calculated for these features using conditional logistic regression, and positive predictive values (PPVs) were calculated. RESULTS: A total of 7471 cases and 32 877 controls were studied. Sixteen features were independently associated with oesophago-gastric cancer (all P<0.001): dysphagia, OR 139 (95% confidence interval 112-173); reflux, 5.7 (4.8-6.8); abdominal pain, 2.6 (2.3-3.0); epigastric pain, 8.8 (7.0-11.0); dyspepsia, 6 (5.1-7.1); nausea and/or vomiting, 4.9 (4.0-6.0); constipation, 1.5 (1.2-1.7); chest pain, 1.6 (1.4-1.9); weight loss, 8.9 (7.1-11.2); thrombocytosis, 2.4 (2.0-2.9); low haemoglobin, 2.4 (2.1-2.7); low MCV, 5.2 (4.2-6.4); high inflammatory markers, 1.7 (1.4-2.0); raised hepatic enzymes, 1.3 (1.2-1.5); high white cell count, 1.4 (1.2-1.7); and high cholesterol, 0.8 (0.7-0.8). The only PPV >5% in patients ≥55 years was for dysphagia. In patients <55 years, all PPVs were <1%. CONCLUSION: Symptoms of oesophago-gastric cancer reported in secondary care were also important in primary care. The results should inform guidance and commissioning policy for upper GI endoscopy.

Immobilization-Free Determination of Dissociation Constants Independent of Ligand Size Using MicroScale Thermophoresis.

The quantitative characterization of aptamer-ligand interactions is an important step in the aptamer development process. However, certain pitfalls impede KD determination, especially when working with small molecule ligands. These include altered binding behavior caused by ligand immobilization. Further, the compulsory requirement for major differences in size between the bound and unbound state makes small molecule ligands ineligible for separation-based methods. MicroScale Thermophoresis circumvents such limitations as binding is accurately quantified with both binding partners free in solution and independent of ligand size. In this chapter, we present a protocol for the characterization of a DNA aptamer binding to its small molecule ligand daunorubicin.

Variation between countries in the frequency of diabetic ketoacidosis at first presentation of type 1 diabetes in children: a systematic review.

AIMS/HYPOTHESIS: Type 1 diabetes is the most frequent endocrine disease in children, with 65,000 children diagnosed worldwide every year. Up to 80% of these children present with diabetic ketoacidosis (DKA), which is associated with both short-term risks and long-term consequences. This study aimed to characterise the worldwide variation in presentation of type 1 diabetes to inform future interventions to reduce this excess morbidity and mortality. METHODS: This was a systematic review of studies indexed on PubMed, EMBASE, Web of Science, Scopus or CINAHL before March 2011 that included unselected groups of children presenting with new-onset type 1 diabetes, reported the proportion presenting with DKA and used a definition of DKA based on measurement of pH or bicarbonate. RESULTS: Sixty-five studies of cohorts comprising over 29,000 children in 31 countries were included. The frequency of DKA at diagnosis ranged from 12.8% to 80%, with highest frequencies in the United Arab Emirates, Saudi Arabia and Romania, and the lowest in Sweden, the Slovak Republic and Canada. Multivariable modelling showed the frequency of DKA was inversely associated with gross domestic product, latitude and background incidence of type 1 diabetes. CONCLUSIONS/INTERPRETATION: This is the first description of the variation in frequency of DKA at presentation of type 1 diabetes in children across countries. It demonstrates large variations that may, at least in part, be explained by different levels of disease awareness and healthcare provision and suggests ways to decrease the excess morbidity and mortality associated with DKA at diagnosis.

The risk of pancreatic cancer in symptomatic patients in primary care: a large case-control study using electronic records.

BACKGROUND: Over 8000 new pancreatic cancers are diagnosed annually in the UK; most at an advanced stage, with only 3% 5-year survival. We aimed to identify and quantify the risk of pancreatic cancer for features in primary care. METHODS: A case-control study using electronic primary care records identified and quantified the features of pancreatic cancer. Cases, aged ≥40 in the General Practice Research Database, UK, with primary pancreatic cancer were matched with controls on age, sex and practice. Putative features of pancreatic cancer were identified in the year before diagnosis. Odds ratios (OR) were calculated for features of cancer using conditional logistic regression. Positive predictive values (PPV) were calculated for consulting patients. RESULTS: In all, 3635 cases and 16,459 controls were studied. Nine features were associated with pancreatic cancer (all P<0.001 except for back pain, P=0.004); jaundice, OR 1000 (95% confidence interval (CI) 4,302,500); abdominal pain, 5 (4.4, 5.6); nausea/vomiting, 4.5 (3.5, 5.7); back pain, 1.4 (1.1, 1.7); constipation, 2.2 (1.7, 2.8); diarrhoea, 1.9 (1.5, 2.5); weight loss, 15 (11, 22); malaise, 2.4 (1.6, 3.5); new-onset diabetes 2.1 (1.7, 2.5). Positive predictive values for patients aged ≥60 were <1%, apart from jaundice at 22% (95% CI 14, 52), though several pairs of symptoms had PPVs >1%. CONCLUSION: Most previously reported symptoms of pancreatic cancer were also relevant in primary care. Although predictive values were small - apart from jaundice - they provide a basis for selection of patients for investigation, especially with multiple symptoms.

The Aarhus statement: improving design and reporting of studies on early cancer diagnosis.

Early diagnosis is a key factor in improving the outcomes of cancer patients. A greater understanding of the pre-diagnostic patient pathways is vital yet, at present, research in this field lacks consistent definitions and methods. As a consequence much early diagnosis research is difficult to interpret. A consensus group was formed with the aim of producing guidance and a checklist for early cancer-diagnosis researchers. A consensus conference approach combined with nominal group techniques was used. The work was supported by a systematic review of early diagnosis literature, focussing on existing instruments used to measure time points and intervals in early cancer-diagnosis research. A series of recommendations for definitions and methodological approaches is presented. This is complemented by a checklist that early diagnosis researchers can use when designing and conducting studies in this field. The Aarhus checklist is a resource for early cancer-diagnosis research that should promote greater precision and transparency in both definitions and methods. Further work will examine whether the checklist can be readily adopted by researchers, and feedback on the guidance will be used in future updates.

Artificial intelligence and machine learning algorithms for early detection of skin cancer in community and primary care settings: a systematic review.

Skin cancers occur commonly worldwide. The prognosis and disease burden are highly dependent on the cancer type and disease stage at diagnosis. We systematically reviewed studies on artificial intelligence and machine learning (AI/ML) algorithms that aim to facilitate the early diagnosis of skin cancers, focusing on their application in primary and community care settings. We searched MEDLINE, Embase, Scopus, and Web of Science (from Jan 1, 2000, to Aug 9, 2021) for all studies providing evidence on applying AI/ML algorithms to the early diagnosis of skin cancer, including all study designs and languages. The primary outcome was diagnostic accuracy of the algorithms for skin cancers. The secondary outcomes included an overview of AI/ML methods, evaluation approaches, cost-effectiveness, and acceptability to patients and clinicians. We identified 14 224 studies. Only two studies used data from clinical settings with a low prevalence of skin cancers. We reported data from all 272 studies that could be relevant in primary care. The primary outcomes showed reasonable mean diagnostic accuracy for melanoma (89·5% [range 59·7-100%]), squamous cell carcinoma (85·3% [71·0-97·8%]), and basal cell carcinoma (87·6% [70·0-99·7%]). The secondary outcomes showed a heterogeneity of AI/ML methods and study designs, with high amounts of incomplete reporting (eg, patient demographics and methods of data collection). Few studies used data on populations with a low prevalence of skin cancers to train and test their algorithms; therefore, the widespread adoption into community and primary care practice cannot currently be recommended until efficacy in these populations is shown. We did not identify any health economic, patient, or clinician acceptability data for any of the included studies. We propose a methodological checklist for use in the development of new AI/ML algorithms to detect skin cancer, to facilitate their design, evaluation, and implementation.

The implementation of pharmacogenomics into UK general practice: a qualitative study exploring barriers, challenges and opportunities.

Pharmacogenomics describes interpatient genetic variability in drug responses. Information based on whole genome sequencing will soon open up the field of pharmacogenomics and facilitate the use of genomic information relating to drug metabolism and drug responses. We undertook a qualitative study, aiming to explore the potential barriers, opportunities and challenges facing the implementation of pharmacogenomics into primary care. Semi-structured interviews were undertaken with 18 clinical participants (16 GPs and 2 other clinicians). All interviews were recorded and transcribed verbatim. Using a thematic analysis approach, data items were coded, ordered and themes constructed. Most participants were aged 55-60 years and worked as part-time clinical GPs with other clearly defined roles. The emerging themes covered several areas of concern, including the following: the utility of pharmacogenomics and the value of introducing such testing into primary care; how to educate the primary care workforce and 'mainstream' pharmacogenomics; the ethical, legal and social aspects of pharmacogenomics and its impact on patients; and potential impacts on the healthcare system particularly around economics and informatics. Most participants had concerns about pharmacogenomics and felt that there were a number of barriers and challenges to its implementation into routine primary care. Most striking were their concerns around the cost-effectiveness of using pharmacogenomics in primary care. At the same time most recognised the increasing availability of direct-to-consumer testing, and felt that this would drive the need to understand the ethical and social implications of using genomic information in primary care. This study has raised important issues that need to be considered when planning the implementation of pharmacogenomics into clinical practice. Prior to the implementation of genomic testing into day-to-day practice in UK primary care, it is important that considerations around education, cost-effectiveness and informatics are addressed, as well as the impact on patients.