Estimating cancer survival in populations - and public health applications

Michel Coleman, LSHTM

Randomised controlled trials measure the highest achievable survival, while population studies estimate the average survival actually achieved. This simple dichotomy has major implications for both the data and the methodology required to estimate cancer survival. It also affects the interpretation of survival estimates for public health and policy-making, their applicability to recent or current clinical practice, and the feasibility of examining long-term survival.

Population-based survival estimates for cancer comprise one of the essential tools for monitoring the efficacy and equity of a national cancer treatment programme. The use of crude, net and relative survival estimates will be discussed in the context of their use as health service performance indicators, as well as for the study of cancer survival trends, socio-economic and geographic inequalities in survival, the proportion of patients who can be said to have been cured, and the number of deaths that would be avoidable if socio-economic inequalities in survival were eliminated. The public health and policy applications of cancer survival data will be illustrated with results from cancer survival studies in England and Wales, Scotland, Europe and the USA.