Diagnosing cancer earlier: reviewing the evidence for improving cancer survival

摘要

Since publication of the BJC supplement, volume 101; ‘Evidence for a National Awareness and Early Diagnosis Initiative' (NAEDI) in December 2009, there has been considerable investment and significant research, data collection, analysis, policy activity and application of interventions under the auspices of NAEDI. We have come a long way in our understanding of the role early cancer diagnosis has in improving survival; we have deeper insights as to what might be done to achieve it and better ways to measure progress. The 2009 supplement presented diverse evidence relevant to early diagnosis, linking late diagnosis with poor survival and ‘avoidable deaths', going so far as to quantify this ( Abdel-Rahman et al , 2009 ) – figures that have been used to drive increased spending and activity in the area since. Five years on, we present selected primary research, reviews, evaluations and discussion pieces assessing the recent evidence available for earlier diagnosis and suggesting areas for further research. This introduction aims to bring the reader up to date, offers a contemporary view of our efforts to guide action to improve survival and reduce premature mortality from cancer and notes key findings from papers within this supplement (BJC, 2015). NAEDI was launched in November 2008 ( Richards, 2009 ), and it remains to be co-chaired by the National Cancer Director and Cancer Research UK's Chief Executive, with close involvement from the Department of Health and a wide variety of partners across the health and third sectors, as well as a burgeoning research community. Its main aim is to address poor cancer survival by reducing the number and proportion of cancers diagnosed and treated at a late stage, mainly concentrating on symptomatic presentation and improvements across the diagnostic pathway. This is not to say that screening programmes, the development of new technologies or biomarkers, are not a vital part of the early diagnosis armoury, but simply that these are dealt with elsewhere and NAEDI concerns itself with sharing best practice and applying new intelligence to optimising pathways, approaches and behaviours. Our knowledge of the cancer types for which symptoms are indicative of ‘early'-stage disease (as opposed to when the disease is already advanced) is far from complete and remains an important focus for future research if we are to apply efforts for greatest effect where they will most likely improve cancer outcomes. The 2007 Cancer Reform Strategy ( Department of Health, 2007 ) and subsequent Improving Outcomes Strategy for Cancer ( Department of Health, 2011 ) placed a deliberate focus on the role of primary care in diagnosing cancer earlier, and research and understanding in this area have grown apace. The National Health Service (NHS) reforms of 2012 saw the end of a number of bodies and functions with responsibility for taking forward the NAEDI agenda, as well as creation of NHS England and Public Health England, both of which are essential partners in our efforts within England to detect, diagnose and treat cancers as swiftly and effectively as possible. One such partnership in England has been the development and execution of ‘ Be Clear on Cancer' , a series of public awareness campaigns whose aim, along with other related activities, is to increase public knowledge of key cancer signs and symptoms in order to encourage swifter presentation to primary care and thus more timely investigation and diagnosis. An extensive evaluation of the national lung cancer campaign was recently published in this journal ( Ironmonger et al , 2015 ), whereas two further assessments of the first national bowel and lung cancer campaigns are presented in this supplement. The first ( Moffat et al , 2015 ) looks at the impact on socio-demographic inequalities in awareness and GP attendance, and the second assesses the change in knowledge and perceived barriers to help-seeking ( Power and Wardle, 2015 ). In Scotland, ‘Detect Cancer Earlier' has been implemented with similar objectives (The Scottish Government, 2014) and Cancer Research UK, among others, is working with health departments in Wales and Northern Ireland on future possibilities. Since the 2009 BJC supplement, research into early diagnosis has increased in both volume and scope, with new funding streams created with the express purpose of facilitating creation of a body of evidence to underpin activity to address late diagnosis and a consolidated research community. Being a complex and truly multidisciplinary research area, it combines behavioural science, primary-care research, epidemiology, policy and health services research, international comparison studies, data analysis and practice evaluation. This is crucial when you consider the original ‘NAEDI hypothesis' ( Richards, 2009 ) updated here, indicating the multifactorial and often nonlinear nature of the pathways to diagnosis from the first onset of symptoms and the individual's response, to