Global survival patterns: potential for cancer control
Authors: Linda C Harlan, Joan L Warren
Journal: The Lancet (2014)

In 2011, member states of the UN General Assembly established an objective to reduce premature deaths from non-communicable diseases (including cancer) by 25% by 2025.1Kontis V Mathers CD Rehm J et al.Contribution of six risk factors to achieving the 25 × 25 non-communicable disease mortality reduction target: a modelling study.Lancet. 2014; 384: 427-437Summary Full Text Full Text PDF PubMed Scopus (287) Google Scholar A reduction in cancer mortality can only be achieved through disease control programmes that include prevention, early diagnosis, and treatment of malignant disease. Nearly a decade ago, the World Health Assembly called on its member states to create “national cancer plans and programs”.2Nieburg HE Cancer prevention and control strategy resolution adopted by the 58th World Health Assembly, Geneva, May 25, 2005.Cancer Detect Prev. 2005; 29: 403-404Summary Full Text Full Text PDF PubMed Scopus (7) Google Scholar The need for such initiatives has escalated in the intervening years. The burden of cancer is growing worldwide, not only because the population is ageing in many countries (attributable in part to improved control of communicable diseases) but also because of changes in risk factors (eg, increasing prevalence of tobacco smoking and obesity).3Vineis P Wild CP Global cancer patterns: causes and prevention.Lancet. 2014; 383: 549-557Summary Full Text Full Text PDF PubMed Scopus (455) Google Scholar To establish priorities for cancer control programmes, governments must have sufficient information to record the burden of cancer in their countries. Comprehensive, high-quality cancer registration is a key component needed to assess the effectiveness of disease control programmes, and cancer registries have been endorsed by WHO.4Valsecchi MG Steliarova-Foucher E Cancer registration in developing countries: luxury or necessity?.Lancet Oncol. 2008; 9: 159-167Summary Full Text Full Text PDF PubMed Scopus (126) Google Scholar In The Lancet, Claudia Allemani and colleagues in the CONCORD Working Group5Allemani C Weir HK Carreira H et al.the CONCORD Working GroupGlobal surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2).Lancet. 2014; (published online Nov 26.)http://dx.doi.org/S0140-6736(14)62038-9PubMed Google Scholar describe the efforts of the CONCORD-2 programme to initiate global surveillance of cancer survival, examining survival trends from 1995 to 2009. They assembled a global cancer dataset, with information for almost 26 million individual cancer patients provided by 279 population-based cancer registries in 67 countries.5Allemani C Weir HK Carreira H et al.the CONCORD Working GroupGlobal surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2).Lancet. 2014; (published online Nov 26.)http://dx.doi.org/S0140-6736(14)62038-9PubMed Google Scholar The group must be commended for the technical, scientific, and political efforts needed to obtain these data. Allemani and colleagues5Allemani C Weir HK Carreira H et al.the CONCORD Working GroupGlobal surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2).Lancet. 2014; (published online Nov 26.)http://dx.doi.org/S0140-6736(14)62038-9PubMed Google Scholar report an increase in 5-year survival from colon, rectal, and breast cancer in most developed countries. One striking finding was for childhood acute lymphoblastic leukaemia, for which very wide variations in survival were noted globally—eg, less than 60% in several countries but 90% or higher in Canada and four European countries (Austria, Belgium, Germany, and Norway)—which suggests an absence of adequate treatment for children in particular regions of the world. The potential for cancer prevention programmes was highlighted by poor survival in most countries from lung and liver cancer—generally 10–20% (for both cancers, 5-year survival is below 20% in Europe, 15–19% in North America, and as low as 7–9% in Mongolia and Thailand). Most countries have not seen significant improvement in 5-year survival from ovarian cancer, which generally varies between 30% and 50%; only ten of 61 countries have seen increases in survival of more than 5% between 1995–99 and 2005–09, and for women diagnosed during 2005–09, 5-year survival exceeded 40% only in Ecuador, the USA, and 17 countries in Asia and Europe. The improvement up to 2005–09 in 5-year survival from cervical cancer, a cancer that can be screen detected, has generally been limited, ranging from below 50% to 70% or higher. This contrasts with survival trends for prostate cancer. Allemani and colleagues report increases of 10–20% in 5-year prostate cancer survival between 1995–99 and 2005–09 in 22 countries in South America, Asia, and Europe, but the global range is still wide, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. These increases are probably due in large part to the increasingly widespread use of PSA testing for earlier detection. Early diagnosis and treatment of malignant disease are likely to have played a part in the global variability in cancer survival. Survival patterns and trends provide researchers and policy makers with evidence of the effectiveness of cancer control programmes, and the findings of this global analysis can be used to plan and evaluate such programmes. Although the CONCORD-2 analysis provides valuable information about cancer survival trends by country, Allemani and colleagues5Allemani C Weir HK Carreira H et al.the CONCORD Working GroupGlobal surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2).Lancet. 2014; (published online Nov 26.)http://dx.doi.org/S0140-6736(14)62038-9PubMed Google Scholar also highlight the scarcity of data available to assess the burden of cancer worldwide. Many areas of the world do not have high-quality population-based cancer registration or did not participate in this global effort. Scant coverage of particular geographical regions might represent areas where patients are at greater risk of either being diagnosed with cancer, being diagnosed at a late stage, or receiving low-quality care. Regions within a country that are not covered by a cancer registry might be areas of lower income, have poorer health care, or be sparsely populated. Countries that operate population-based cancer registries face increasing challenges. Creating and maintaining nationally representative population-based cancer registration is complex and needs resources and political commitment. High-quality cancer registries will have at least 90% ascertainment of cases, with fewer than 5% of cases registered from a death certificate only, and will obtain high-quality data related to the site, stage, and morphological features of cancers.6Bray F Parkin DM Evaluation of data quality in the cancer registry: principles and methods—part I, comparability, validity and timeliness.Eur J Cancer. 2009; 45: 747-755Summary Full Text Full Text PDF PubMed Scopus (414) Google Scholar The potential value of a cancer registry is diminished if the population is not covered completely or if cases are under-ascertained. Moreover, many registries have only scant information about patients' outcomes and do not have the capacity to link cancer registrations to other data. Comprehensive ascertainment of the date and cause of death in registered cancer patients would enhance the usefulness of registries to assess the burden of malignant disease. Implementation of effective cancer control programmes, including the operation of population-based cancer registries, needs support from national governments. For low-income and middle-income countries, such efforts might be difficult, taking into account economic capabilities. Patients, patient advocates, health-care providers and administrators, researchers, and the wider community can all play a part in influencing politicians to provide funds for cancer control efforts. Evaluation of cancer control programmes will serve as a reinforcing mechanism to maintain funding and lead to improvements in these initiatives. In view of the value of data resources such as cancer registries, we would not expect their existence to be at risk. However, as Allemani and colleagues5Allemani C Weir HK Carreira H et al.the CONCORD Working GroupGlobal surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2).Lancet. 2014; (published online Nov 26.)http://dx.doi.org/S0140-6736(14)62038-9PubMed Google Scholar note, concerns are mounting about pending legal and regulatory issues and privacy concerns that could restrict the registration of cancer patients and access to data for research.7Casali PG Risks of the new EU data protection regulation: an ESMO position paper endorsed by the European oncology community.Ann Oncol. 2014; 25: 1458-1461Crossref PubMed Scopus (27) Google Scholar, 8Thomas B Gostin LO Tackling the global NCD crisis: innovations in law and governance.J Law Med Ethics. 2013; 41: 16-27Crossref PubMed Scopus (36) Google Scholar This proposed legislation seems counterproductive to the goal all countries must have to diminish suffering and death from cancer. Data for research are anonymised, without personal identifiers, and are reported in broad categories to enable protection of patients' identities and provide confidentiality. What would be gained by restricting researchers' access to these data is not clear; the loss to society is much clearer. The analyses of global survival reported by Allemani and colleagues provide an opportunity for lessons to be learnt from countries with successful cancer control initiatives, which could be applied to other regions. Undoubtedly, the availability of better data provides a clearer picture of the effect of cancer control programmes on the ultimate goal of improving survival and reducing the effect of cancer on the social and economic development of countries. We declare no competing interests. This Comment is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health. Global surveillance of cancer survival 1995–2009: analysis of individual data for 25 676 887 patients from 279 population-based registries in 67 countries (CONCORD-2)International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems. Full-Text PDF Open Access