Cancer survival in five continents: a worldwide population-based study (CONCORD)

Cancer survival varies widely between countries. The CONCORD study provides survival estimates for 1.9 million adults (aged 15-99 years) diagnosed with a first, primary, invasive cancer of the breast (women), colon, rectum, or prostate during 1990-94 and followed up to 1999, by use of individual tumour records from 101 population-based cancer registries in 31 countries on five continents. This is, to our knowledge, the first worldwide analysis of cancer survival, with standard quality-control procedures and identical analytic methods for all datasets.

To compensate for wide international differences in general population (background) mortality by age, sex, country, region, calendar period, and (in the USA) ethnic origin, we estimated relative survival, the ratio of survival noted in the patients with cancer, and the survival that would have been expected had they been subject only to the background mortality rates. 2800 life tables were constructed. Survival estimates were also adjusted for differences in the age structure of populations of patients with cancer.