OBJECTIVES: Anti-cancer drugs are often challenged on the ground that most clinical trials show modest gains in terms of overall survival associated with high acquisition costs. But in the same time, many oncologists make the point that progress is incremental and should be assessed dynamically on a longer period. We collected various data over a 20 year period (1990-2010) to provide a retrospective view of the progress that has been achieved in medical terms and the amount of public resources that has been spent through better treatments. METHODS: We constructed two scenarios. The first one is a reconstruction of what actually happened. On a yearly basis, we follow the patients who reported to have a cancer to Health Insurance.  We computed the incident cases, the number of deaths, the number of surviving patients and the average and total treatment costs, from the public payer’s perspective. The second one is a “counterfactual” scenario which differs only by the assumption that medical progress has stopped in 1990. Efficacy  and cost of medicines are maintained equal to their 1990 values on the whole remaining period. RESULTS: In that hypothetical scenario, the public payer spares nearly 60 billions of current Euros over the whole period, compared to the “real scenario”, partly because of a fewer number of patients to treat, partly because of a lower average treatment cost. But in the same time, the number of deceased patients rises by 670,000 and the number of lost years of life by 3.2 million. This means that retrospectively the medical progress has allowed to save one additional year of life at a marginal cost of 18,500 €. in current value for the public payer.  CONCLUSIONS: Investing in new and innovative cancer treatments was an effective and a cost-effective use of public resources in years 1990-2010.