The Challenge Ahead: Progress and Setbacks in Breast and Cervical Cancer
This is the first global assessment of country-specific trends in breast and cervical cancer for all countries by age, and the findings were simultaneously published in The Lancet on September 14, 2011.
Related Publications & Presentations
Forouzanfar MH, Foreman KJ, Delossantos AM, Lozano R, Lopez AD, Murray CJL, Naghavi M. Breast and cervical cancer in 187 countries between 1980 and 2010: a systematic analysis. The Lancet. 2011; DOI:10.1016/S0140-6736(11)61351-2.
Related News & Events
In September 2011, IHME published in The Lancet global estimates for breast and cervical cancer: Breast and cervical cancer in 187 countries between 1980 and 2010: a systematic analysis. The new estimates differed from estimates available from the International Agency for Research on Cancer through the GLOBOCAN website.
- We based our estimates on additional data sources, especially for cancer deaths. For example, in some countries that lack vital registration data, we were able to use data from verbal autopsy studies, which gather information from relatives about how a family member died. Even in countries where rich data sources are available, IARC used modeled mortality estimates from the World Health Organization. For cervical cancer deaths in India, for example, the IARC approach yields a much higher number of deaths than the IHME approach.
- In both vital registration systems and cancer registries, many cancer deaths are inaccurately coded or ill-defined by the agencies collecting the data. Using methodological tools designed at IHME, we fixed the coding and assigned the deaths to the appropriate categories.
- To generate the mortality-to-incidence (MI) ratio, a key measure for the number of women with cancer who die annually, we improved on previous methods by factoring in age, country, and year. We have found that our estimates are in sync with data from cancer registries.
- We use one approach for estimating mortality data in 187 countries. GLOBOCAN data are based on 26 different approaches for different groups of countries. The approach used for Saudi Arabia and South Africa, for example, is different from the one used for Vietnam and China.
- Many of the approaches used for estimating mortality in the GLOBOCAN data rely on trends observed in Nordic countries. We believe relying on such a limited number of countries leads to an overestimation of MI ratios in many developing countries, particularly for breast cancer.
A detailed discussion of our methods can be found in the Web Appendix with the journal article.