More than a decade into the 21st century, we are at a major crossroads in our understanding of cancer. Tools of molecular biology, genomics, and other high throughput "omic" technologies are increasingly integrated into epidemiologic investigations. In a 2011 town hall meeting, Dr. Harold Varmus, NCI Director, said, "I expect to see a pretty dramatic revolution in epidemiology... defining cancers by genetic subsets. I expect to see molecular tools brought more forcefully into the realm of cancer diagnosis... talking about ways to discriminate among early lesions and pre-cancerous lesions that may have malignant potential."
Along with these emerging tools come refined social, behavioral, and environmental exposure measurements at the individual, community, and health system levels and the ability to assess gene-gene and gene-environment interactions. There is an increased focus on complex "systems" approaches in understanding the occurrence of cancer and intervening at multiple levels. All this has been influenced by tremendous advances in bioinformatics and information technology, allowing us to collect, analyze, and synthesize information from multiple disciplines at an ever increasing pace.
With these opportunities, however, come the major challenge of dealing with the data deluge and uncovering true causal relationships from the millions and millions of observations that are background noise. At the same time, increased consumer awareness and education has led to enhanced participation and co-ownership of research and research output. Thus, epidemiology now confronts important challenges and opportunities in the study of cancer and other diseases, and must make choices of direction, as it responds to rapid changes in the environment.