Willie Hamilton

The expanding role of primary care in cancer control

The nature of cancer control is changing, with an increasing emphasis, fuelled by public and political demand, on prevention, early diagnosis, and patient experience during and after treatment. At the same time, primary care is increasingly promoted, by governments and health funders worldwide, as the preferred setting for most health care for reasons of increasing need, to stabilise health-care costs, and to accommodate patient preference for care close to home. It is timely, then, to consider how this expanding role for primary care can work for cancer control, which has long been dominated by highly technical interventions centred on treatment, and in which the contribution of primary care has been largely perceived as marginal. In this Commission, expert opinion from primary care and public health professionals with academic and clinical cancer expertise—from epidemiologists, psychologists, policy makers, and cancer specialists—has contributed to a detailed consideration of the evidence for cancer control provided in primary care and community care settings. Ranging from primary prevention to end-of-life care, the scope for new models of care is explored, and the actions needed to effect change are outlined. The strengths of primary care—its continuous, coordinated, and comprehensive care for individuals and families—are particularly evident in prevention and diagnosis, in shared follow-up and survivorship care, and in end-of-life care. A strong theme of integration of care runs throughout, and its elements (clinical, vertical, and functional) and the tools needed for integrated working are described in detail. All of this change, as it evolves, will need to be underpinned by new research and by continuing and shared multiprofessional development.

Preferences for cancer investigation: a vignette-based study of primary-care attendees

BACKGROUND The UK lags behind many European countries in terms of cancer survival. Initiatives to address this disparity have focused on barriers to presentation, symptom recognition, and referral for specialist investigation. Selection of patients for further investigation has come under particular scrutiny, although preferences for referral thresholds in the UK population have not been studied. We investigated preferences for diagnostic testing for colorectal, lung, and pancreatic cancers in primary-care attendees. METHODS In a vignette-based study, researchers recruited individuals aged at least 40 years attending 26 general practices in three areas of England between Dec 6, 2011, and Aug 1, 2012. Participants completed up to three of 12 vignettes (four for each of lung, pancreatic, and colorectal cancers), which were randomly assigned. The vignettes outlined a set of symptoms, the risk that these symptoms might indicate cancer (1%, 2%, 5%, or 10%), the relevant testing process, probable treatment, possible alternative diagnoses, and prognosis if cancer were identified. Participants were asked whether they would opt for diagnostic testing on the basis of the information in the vignette. FINDINGS 3469 participants completed 6930 vignettes. 3052 individuals (88%) opted for investigation in their first vignette. We recorded no strong evidence that participants were more likely to opt for investigation with a 1% increase in risk of cancer (odds ratio [OR] 1·02, 95% CI 0·99-1·06; p=0·189), although the association between risk and opting for investigation was strong when colorectal cancer was analysed alone (1·08, 1·03-1·13; p=0·0001). In multivariable analysis, age had an effect in all three cancer models: participants aged 60-69 years were significantly more likely to opt for investigation than were those aged 40-59 years, and those aged 70 years or older were less likely. Other variables associated with increased likelihood of opting for investigation were shorter travel times to testing centre (colorectal and lung cancers), a family history of cancer (colorectal and lung cancers), and higher household income (colorectal and pancreatic cancers). INTERPRETATION Participants in our sample expressed a clear preference for diagnostic testing at all risk levels, and individuals want to be tested at risk levels well below those stipulated by UK guidelines. This willingness should be considered during design of cancer pathways, particularly in primary care. The public engagement with our study should encourage general practitioners to involve patients in referral decision making. FUNDING The National Institute for Health Research Programme Grants for Applied Research programme.

Explaining variation in cancer survival between 11 jurisdictions in the International Cancer Benchmarking Partnership: a primary care vignette survey

Objectives The International Cancer Benchmarking Partnership (ICBP) is a collaboration between 6 countries and 12 jurisdictions with similar primary care-led health services. This study investigates primary care physician (PCP) behaviour and systems that may contribute to the timeliness of investigating for cancer and subsequently, international survival differences. Design A validated survey administered to PCPs via the internet set out in two parts: direct questions on primary care structure and practice relating to cancer diagnosis, and clinical vignettes, assessing management of scenarios relating to the diagnosis of lung, colorectal or ovarian cancer. Participants 2795 PCPs in 11 jurisdictions: New South Wales and Victoria (Australia), British Columbia, Manitoba, Ontario (Canada), England, Northern Ireland, Wales (UK), Denmark, Norway and Sweden. Primary and secondary outcome measures Analysis compared the cumulative proportion of PCPs in each jurisdiction opting to investigate or refer at each phase for each vignette with 1-year survival, and conditional 5-year survival rates for the relevant cancer and jurisdiction. Logistic regression was used to explore whether PCP characteristics or system differences in each jurisdiction affected the readiness to investigate. Results 4 of 5 vignettes showed a statistically significant correlation (p<0.05 or better) between readiness to investigate or refer to secondary care at the first phase of each vignette and cancer survival rates for that jurisdiction. No consistent associations were found between readiness to investigate and selected PCP demographics, practice or health system variables. Conclusions We demonstrate a correlation between the readiness of PCPs to investigate symptoms indicative of cancer and cancer survival rates, one of the first possible explanations for the variation in cancer survival between ICBP countries. No specific health system features consistently explained these findings. Some jurisdictions may consider lowering thresholds for PCPs to investigate for cancer—either directly, or by specialist referral, to improve outcomes.

Rebuttal to editorial saying cancer survival statistics are misleading

Beral and Peto’s 2010 editorial on cancer survival statistics is unfounded, untenable, and inconsistent.1 Godlee reported in September 2010 that they were then too busy to defend it.2 The editorial is indefensible. It should be withdrawn. The editorial is unfounded. The provocative subtitle, “UK cancer survival statistics are misleading and make survival look worse than it is,” is pure conjecture. Conjecture becomes assertion, then …

Development of a survey instrument to investigate the primary care factors related to differences in cancer diagnosis between international jurisdictions.

BackgroundSurvival rates following a diagnosis of cancer vary between countries. The International Cancer Benchmarking Partnership (ICBP), a collaboration between six countries with primary care led health services, was set up in 2009 to investigate the causes of these differences. Module 3 of this collaboration hypothesised that an association exists between the readiness of primary care physicians (PCP) to investigate for cancer – the ‘threshold’ risk level at which they investigate or refer to a specialist for consideration of possible cancer – and survival for that cancer (lung, colorectal and ovarian). We describe the development of an international survey instrument to test this hypothesis.MethodsThe work was led by an academic steering group in England. They agreed that an online survey was the most pragmatic way of identifying differences between the jurisdictions. Research questions were identified through clinical experience and expert knowledge of the relevant literature.A survey comprising a set of direct questions and five clinical scenarios was developed to investigate the hypothesis. The survey content was discussed and refined concurrently and repeatedly with international partners. The survey was validated using an iterative process in England. Following validation the survey was adapted to be relevant to the health systems operating in other jurisdictions and translated into Danish, Norwegian and Swedish, and into Canadian and Australian English.ResultsThis work has produced a survey with face, content and cross cultural validity that will be circulated in all six countries. It could also form a benchmark for similar surveys in countries with similar health care systems.ConclusionsThe vignettes could also be used as educational resources. This study is likely to impact on healthcare policy and practice in participating countries.

Improving early diagnosis of symptomatic cancer

Much time, effort and investment goes into the diagnosis of symptomatic cancer, with the expectation that this approach brings clinical benefits. This investment of resources has been particularly noticeable in the UK, which has, for several years, appeared near the bottom of international league tables for cancer survival in economically developed countries. In this Review, we examine expedited diagnosis of cancer from four perspectives. The first relates to the potential for clinical benefits of expedited diagnosis of symptomatic cancer. Limited evidence from clinical trials is available, but the considerable observational evidence suggests benefits can be obtained from this approach. The second perspective considers how expedited diagnosis can be achieved. We concentrate on data from the UK, where extensive awareness campaigns have been conducted, and initiatives in the primary-care setting, including clinical decision support, have all occurred during a period of considerable national policy change. The third section considers the most appropriate patients for cancer investigations, and the possible community settings for identification of such patients; UK national guidance for selection of patients for investigation is discussed. Finally, the health economics of expedited diagnosis are reviewed, although few studies provide definitive evidence on this topic.

Risk prediction tools for cancer in primary care.

Numerous risk tools are now available, which predict either current or future risk of a cancer diagnosis. In theory, these tools have the potential to improve patient outcomes through enhancing the consistency and quality of clinical decision-making, facilitating equitable and cost-effective distribution of finite resources such as screening tests or preventive interventions, and encouraging behaviour change. These potential uses have been recognised by the National Cancer Institute as an ‘area of extraordinary opportunity’ and an increasing number of risk prediction models continue to be developed. The data on predictive utility (discrimination and calibration) of these models suggest that some have potential for clinical application; however, the focus on implementation and impact is much more recent and there remains considerable uncertainty about their clinical utility and how to implement them in order to maximise benefits and minimise harms such as over-medicalisation, anxiety and false reassurance. If the potential benefits of risk prediction models are to be realised in clinical practice, further validation of the underlying risk models and research to assess the acceptability, clinical impact and economic implications of incorporating them in practice are needed.

Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data

Background Thrombocytosis (raised platelet count) is an emerging risk marker of cancer, but the association has not been fully explored in a primary care context. Aim To examine the incidence of cancer in a cohort of patients with thrombocytosis, to determine how clinically useful this risk marker could be in predicting an underlying malignancy. Design and setting A prospective cohort study using Clinical Practice Research Datalink data from 2000 to 2013. Method The 1-year incidence of cancer was compared between two cohorts: 40 000 patients aged ≥40 years with a platelet count of >400 × 109/L (thrombocytosis) and 10 000 matched patients with a normal platelet count. Sub-analyses examined the risk with change in platelet count, sex, age, and different cancer sites. Results A total of 1098 out of 9435 males with thrombocytosis were diagnosed with cancer (11.6%; 95% confidence interval [CI] = 11.0 to 12.3), compared with 106 of 2599 males without thrombocytosis (4.1%; 95% CI = 3.4 to 4.9). A total of 1355 out of 21 826 females with thrombocytosis developed cancer (6.2%; 95% CI = 5.9 to 6.5), compared with 119 of 5370 females without (2.2%; 95% CI = 1.8 to 2.6). The risk of cancer increased to 18.1% (95% CI = 15.9 to 20.5) for males and 10.1% (95% CI = 9.0 to 11.3) for females, when a second raised platelet count was recorded within 6 months. Lung and colorectal cancer were more commonly diagnosed with thrombocytosis. One-third of patients with thrombocytosis and lung or colorectal cancer had no other symptoms indicative of malignancy. Conclusion Thrombocytosis is a risk marker of cancer in adults; 11.6% and 6.2% cancer incidence in males and females, respectively, is worthy of further investigation for underlying malignancy. These figures well exceed the National Institute for Health and Care Excellence-mandated risk threshold of 3% risk to warrant referral for suspected cancer.

How useful is thrombocytosis in predicting an underlying cancer in primary care? a systematic review

Background. Although the association between raised platelet count (thrombocytosis) and cancer has been reported in primary and secondary care studies, UK GPs are unaware of it, and it is insufficiently evidenced for laboratories to identify and warn of it. This systematic review aimed to identify and collate evidence from studies that have investigated thrombocytosis as an early marker of cancer in primary care. Methods. EMBASE (OvidSP), Medline (Ovid), Web of Science and The Cochrane Library were searched for relevant studies. Eligible studies had reported estimates of the association between thrombocytosis and cancer, in adults aged ≥40 in a primary care setting. Raw data from included studies were used to calculate positive predictive values and likelihood ratios (LRs) for cancer. Results. Nine case–control studies were identified. Study quality was judged to be high. Included studies reported on the following cancer sites: colorectal, lung, ovary, bladder, kidney, pancreas, oesophago-gastric, uterus and breast. LRs indicated that thrombocytosis was a predictor of cancer in all sites except breast. In a consulting population, thrombocytosis is most highly predictive of lung and colorectal cancer. Conclusions. These results suggest that patients with thrombocytosis in primary care have an increased risk of cancer, and that some, but not all, cancers have raised platelets as an early marker. This finding is expected to be of use in primary care, for GPs receiving blood test results unexpectedly showing high platelet counts. Further research is needed to identify the cancers that are most strongly associated with thrombocytosis.

For which cancers might patients benefit most from expedited symptomatic diagnosis? Construction of a ranking order by a modified Delphi technique

BackgroundThis study aimed to answer the question ‘for which cancers, in a symptomatic patient, does expediting the diagnosis provide an improvement in mortality and/or morbidity?’MethodsAn initial ranking was constructed from previous work identifying ‘avoidable deaths’ for 21 common cancers in the UK. In a two-round modified Delphi exercise, 22 experts, all experienced across multiple cancers, used an evidence pack summarising recent relevant publications and their own experience to adjust this ranking. Participants also answered on a Likert scale whether they anticipated mortality or morbidity benefits for each cancer from expedited diagnosis.ResultsSubstantial changes in ranking occurred in the Delphi exercise. Finally, expedited diagnosis was judged to provide the greatest mortality benefit in breast cancer, uterine cancer and melanoma, and least in brain and pancreatic cancers. Three cancers, prostate, brain and pancreas, attracted a median answer of ‘disagree’ to whether they expected mortality benefits from expedited diagnosis of symptomatic cancer.ConclusionsOur results can guide future research, with emphasis given to studying interventions to improve symptomatic diagnosis of those cancers ranked highly. In contrast, research efforts for cancers with the lowest rankings could be re-directed towards alternative avenues more likely to yield benefit, such as screening or treatment.