Malignant neoplasia in mammary gland, prostate and colon appear at the top end of the cancer incidence and mortality statistics in Germany. In this context cost-of-illness studies are a suitable tool for quantifying disease-specific health economic consequences of disease. Their primary aim is to illustrate the economic burden of a specific disease and its implications for society and for the national economy. The present review summarizes the methods and results of cost-of-illness studies regarding the three cancer diseases mentioned. Despite some limitations and remarkable differences in respect of methodological aspects, it is possible to point out that numerous studies lead to similar results. For all three kinds of cancer, there is sufficient evidence to suggest that mainly initial and terminal states of disease are important, due to the major resource utilization caused by the claim of initial and palliative therapies. Inpatient costs--caused by the high rate of hospitalisation--account for 50% to 98% of the direct costs. As regards the societal perspective, a comparison of the three diseases considered demonstrates that especially the costs associated with breast cancer present a big challenge to the health care systems, which is primarily due to the high incidence rate in women under 65 years of age and the correspondingly high indirect costs resulting from invalidity, invalidity pensions or premature death. Future tasks to work on include analyzing the different patterns of health service utilisation and identifying the cost effects of different influencing factors. Transparency of costs, as a basis for cost-effectiveness analyses, could help to make interventions more precise.