[Interest in and limitations of economic assessment applied to the evaluation of medical strategies: examples in oncological hematology].

Using examples of economic assessment of medical innovations in the field of oncology, haematology and safety of blood products, the article shows that most of these innovations follow a law of diminishing returns: increasing levels of resources must be devoted in order to obtain an additional unit of health benefit (such as a life-year saved by a medical intervention). The article argues that, in such a context, cost-benefit analysis, a standard method in public economics, can be a useful tool to determine the 'optimal' level of resources that should be allocated by society for various medical interventions. In some instances, cost-benefit analysis can help to identify barriers to optimal diffusion of medical innovations that are due to inappropriate incentives and constraints in the management of the healthcare system.