Cancer is a highly complex condition. A large number of genetic changes occur within a cell while mutating to the cancerous state. In addition, cancer cells can migrate to other parts of the body and embed themselves into different tissues causing local cells to behave in a genetically different manner. This is because each cell type has a different genetic make-up and will therefore respond differently to invading foreign cells. Cellular interaction and cell signaling within the Tumor area is another complicating factor. Finally, something in the environment (chemicals, radiation, viruses or bacteria) may cause mutations. All of these challenges make early detection and diagnosis very difficult.
In response to this, The Cancer Genome Atlas (TCGA) is a huge multibillion project that builds on the success of its forerunner, the human genome project, to characterize and catalog genetic mutations responsible for cancer through a better understanding of the molecular basis of the disease state. Began in 2005, it initially focused on different types of brain, lung and ovarian cancers because those organs account for more than 210,000 cases a year. The second two-year phase, began in 2010, is studying 20,000 Tumor samples from 20 types of cancer. The third phase will broaden mapping efforts and generate more in-depth analysis of all the cancers studied previously. The success of this project will pave the way for different treatment strategies for different cancers and the development of individualized therapies. It will aid earlier detection and the development of new drugs.