There may be more than 200 different types of cancer and many more subtypes, each caused by glitches in DNA that trigger the uncontrolled growth of cells. Identifying the changes in each cancer’s complete set of DNA - its genome - and understanding how such changes interact to drive the disease process will lay the foundation for an era of precision medicine in cancer care that treats each patient as a unique case.

Toward this end, the National Institutes of Health (NIH) established The Cancer Genome Atlas (TCGA) to generate comprehensive, multi-dimensional maps of the key genomic changes in major types and subtypes of cancer. This catalog serves as a powerful resource for a new generation of research aimed at developing better strategies for diagnosing, treating and preventing cancer. TCGA also provides a model for many other genome mapping projects and serves as a testament to the power of scientific collaboration for both compiling and analyzing a large data set.

Jointly led by the National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI), TCGA is changing the way genetic cancer research is done. Following the example set by the Human Genome Project, TCGA's collaborative research network has brought together researchers from diverse disciplines and multiple institutions to produce valuable data sets for use by the worldwide research community.

A pilot effort initiated by NCI and NHGRI in 2006 developed the policies, production pipeline, collaborative research network, databases and analytical tools necessary for TCGA's large-scale study of cancer genomics. The pilot’s characterizations of brain tumors and ovarian cancer demonstrated that this systematic, high-volume approach can generate unprecedented amounts of data of unparalleled quality, which have been quickly integrated into the work of basic and clinical researchers around the globe.

In September 2009, NCI and NHGRI announced that TCGA planned to produce comprehensive genomic maps of at least 20 types of cancer over the next five years, made possible by the investment of $175 million in American Recovery and Reinvestment Act funds. TCGA was uniquely positioned to achieve this ambitious goal based on the pilot’s success in establishing key infrastructure and processes. With its pipeline in place, TCGA efficiently acquired samples of tumors and matched normal tissue, rapidly sequenced the DNA and RNA of the samples, and comprehensively characterized the genomes using seven genomic platforms.

As TCGA moved forward with the goal of studying more than 20 cancers, the insistence of cancer patients and advocates, and the enthusiasm and engagement of cancer researchers drove TCGA to expand its efforts. In December 2013, when TCGA finalized its collection of matched tumor and normal samples, enough tissue had been collected to map the genomic characteristics of more than 30 cancer types. TCGA analysis working groups, teams of scientists from across the country, have now comprehensively studied 33 cancer types and subtypes, including 10 rare cancers.

This pioneering effort to map and analyze cancer genomes in a large-scale, systematic manner has changed the way cancer is studied, and will ultimately transform the way cancer is treated. Because TCGA data is free to use, it significantly reduces the costs and expedites the process of drug development, enabling both public and private sector researchers to pursue targeted therapies aimed at the specific pathways in a certain cancer type or subtype. This new level of insight, provided by TCGA and future efforts that will build upon the TCGA’s foundation, will chart a new course for cancer research and pioneer the way to more effective, individualized approaches for helping each patient with cancer.