Research on cancer: Why we need to switch the focus from mechanistic research to epidemiology and randomized trials

A major part of medical research is based on the investigation of the biochemical and physiological processes involved in the etiology of disease. This mechanistic research is a weak tool from the perspective of helping to reduce the burden of disease. A far more fruitful strategy has been the study of lifestyle factors associated with risk of disease. Key methods in this area include epidemiology (especially cohort studies and population comparisons) and randomized controlled trials (RCTs). The focus of this paper is cancer. Recent papers estimated the proportion of cancer caused by external factors and that are therefore potentially preventable. A critical examination of these paper supports the hypothesis summarized above.