Rhea Harewood

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)

BACKGROUND Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION 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. FUNDING Canadian Partnership Against Cancer (Toronto, Canada), Cancer Focus Northern Ireland (Belfast, UK), Cancer Institute New South Wales (Sydney, Australia), Cancer Research UK (London, UK), Centers for Disease Control and Prevention (Atlanta, GA, USA), Swiss Re (London, UK), Swiss Cancer Research foundation (Bern, Switzerland), Swiss Cancer League (Bern, Switzerland), and University of Kentucky (Lexington, KY, USA).

Population-Based Cancer Survival in the United States: Data, Quality Control, and Statistical Methods

Robust comparisons of population‐based cancer survival estimates require tight adherence to the study protocol, standardized quality control, appropriate life tables of background mortality, and centralized analysis. The CONCORD program established worldwide surveillance of population‐based cancer survival in 2015, analyzing individual data on 26 million patients (including 10 million US patients) diagnosed between 1995 and 2009 with 1 of 10 common malignancies.

Cervical cancer survival in the United States by race and stage (2001-2009): Findings from the CONCORD-2 study: Cervical Cancer Survival by Race and Stage

Worldwide, liver cancer is a leading cause of death for both men and women. The number of Americans who are diagnosed with and die of liver cancer has been rising slowly each year. Using data from the CONCORD‐2 study, this study examined population‐based survival by state, race, and stage at diagnosis.

Disparities in Ovarian Cancer Survival in the United States (2001–2009): Findings From the CONCORD-2 Study

Ovarian cancer is the fifth leading cause of cancer death among women in the United States. This study reports ovarian cancer survival by state, race, and stage at diagnosis using data from the CONCORD‐2 study, the largest and most geographically comprehensive, population‐based survival study to date.

Adult leukemia survival trends in the United States by subtype: A population-based registry study of 370,994 patients diagnosed during 1995-2009.

The lifetime risk of developing leukemia in the United States is 1.5%. There are challenges in the estimation of population‐based survival using registry data because treatments and prognosis vary greatly by subtype. The objective of the current study was to determine leukemia survival estimates in the United States from 1995 to 2009 according to subtype, sex, geographical area, and race.

Reply to correspondence “Do big numbers assure high-quality of data?”

www.thelancet.com/haematology Vol 4 September 2017 e410 5 Doll R, Payne P, Waterhouse JAH, eds. Cancer incidence in five continents: a technical report. Geneva: UICC; 1966. 6 Martos C, Crocetti E, Visser O, Rous B, Cancer Data Quality Checks Working Group. A proposal on cancer data quality checks: one common procedure for European cancer registries. Ispra, Italy, 2014. http://publications. europa.eu/en/publication-detail/-/publication/ 42d085e9-1d59-4a18-b7d8-325b298baa06/ language-en/format-PDF. (accessed July 15, 2017). 3 Makita S, Tobinai K. Rituximab biosimilars: introduction into clinical practice. Lancet Haematol 2017; 4: e342–43. 4 Weise M, Bielsky MC, De Smet K, et al. Biosimilars: what clinicians should know. Blood 2017; 120: 5111–17. 5 Weise M, Kurki P, Wolff-Holz E, Bielsky MC, Schneider CK. Biosimilars: the science of extrapolation. Blood 2017; 124: 3191–96. necessary to acknowledge data quality as suboptimal. The same approach was adopted in 1966 in the first worldwide compendium of cancer incidence, for regions where information was scarce: “in this situation, even incomplete data have value.” Crocetti and Buzzoni state that the CONCORD quality controls “were mentioned but without reference levels,” citing the summary Article published in The Lancet. However, as with all the 279 registries that participated in CONCORD-2, Crocetti and Buzzoni were sent three reports on data quality in their cancer registry (Tuscany), with the definition of each exclusion criterion, and tables of the number and proportion of records excluded under each criterion. The appendix also contains detailed tables for each cancer, cancer registry, and calendar period. We share Crocetti’s and Buzzoni’s purpose. Crocetti co-authored the EU Joint Research Centre’s proposal for a common procedure on cancer data quality checks, to which we contributed. Harmonisation of quality-control procedures for the data that underpin global cancer control efforts is desirable. More transparent collaboration would be a good start.